Method for correcting the neck-shaft angle of the femur. Cervical-diaphyseal angle of the hip joint in children Cervical-diaphyseal angle

Diagnostics of hip joints
Date of: Monday, February 26 @ 19:49:01 GMT
Subject: Radiation examination of the skeleton

Chapter 1. Hip joint. Terms and concepts.

1. Frontal inclination of the acetabulum– this is the antetorsion of the acetabulum i.e. deviation of the entrance plane to the acetabulum from the frontal plane. In children at the age of 10, the angle is 39º, in adults on average - 42° (for men - 40°, for women - 45°).

2. Cervical-shaft angle (femoral neck inclination angle)– angle between the neck and diaphysis. In adults it is 125° - 135°. In children: newborn. - 134°, 1 year - 148°, 3 years - 145°, 5 years - 142°, 9 years - 138°, in adolescence - 130°.

I. Yu. Zagumennova, E.S. Kuzminova
Regional specialized children's center, Stavropol

3. Antetorsion. In normal relationships, the plane intersecting the axis of the femoral head - femoral neck - diaphysis forms a ventrally open angle with the frontal plane intersecting the condyles of the knee. The reason for this lies in the rotation of the proximal femur. If the rotation occurs under the lesser trochanter, which means that the head, neck and body of the femur are affected equally, then we speak of antetorsion. If only the head and neck of the femur are involved in the rotation, then we are talking about anteversion. In the case of a posterior rotation, they speak of retroversion. At the age of 3 months. the value of antetorsion is 30°, then at the age of 3-4 years - 20°, in the puberty period - about 18°, in adults the average value is 10 - 14°.
In the case of congenital dislocation of the hip, pathological antetorsion is of great importance from the point of view of the prognosis of what?. We speak of pathological antetorsion if the rotation is 10° greater than the corresponding value at a given age. With congenital hip dislocation, increased antetorsion is observed in more than ⅔ of all cases. The consequence of this is a discrepancy between the bones that form the joint, as a result of which the femoral head does not reach the bottom of the acetabulum and is placed outside the center of it. All this leads to defects in the development of the acetabulum and an increased tendency to dislocation, which is very significant from the point of view of the formation of subsequent arthrosis. If antetorsion increases, the body exhibits an active protective reaction: to avoid stress on the hip joint, the lower limbs rotate inward. If at the end of treatment the antetorsion was more than 45°, then the risk of developing subluxation increases to 90%.

4. Varus deformity of the neck (plow vara) is a condition in which the neck-shaft angle is less than the average angle corresponding to age. May be congenital or acquired.

5. Valgus deformity (plow valga) is a condition in which the neck-shaft angle is greater than the average angle corresponding to age. May be congenital or acquired.

Chapter 2. Methods for measuring angles, indices and indicators of the hip joints.

Fig.1. Scheme for calculating anteversion of the proximal end of the femur and frontal inclination of the acetabulum using posterior (a) and axial (b) radiographs

1. Cervical-shaft angle- this is the angle formed at the intersection of the longitudinal axes of the neck and diaphysis of the femur. In Fig. 1, a - this is the angle α

2. Acetabular index reflects the degree of deviation from the horizontal position of the bony part of the roof of the acetabulum visible on the radiograph and is characterized by the angle between the tangent to it and the line connecting both U-shaped cartilages. In Fig. 1,a, this is the angle γ. Normal value: in children over 5 years old 12-16º. (Draw in Fig. 1)

3. Sharpe angle– this is the angle DCB formed by the tangent to the entrance to the acetabulum DC (Fig. 1, a) and the line AC connecting the lower poles of the teardrop figures.

4. Projected anteversion angle- in Fig. 1, b – this is the angle β.

5. Angle of anteversion of the proximal end of the femur. It is found according to the table, where the desired value is located in the area of intersection of the values of the found angles α (neck-shaft angle) and β (projection angle of anteversion).

6. Angle of frontal inclination of the acetabulum. It is found according to the table, where the desired value is located in the area of intersection of the values of the found Sharpe angles and the angle D1C1A1, formed at the intersection of the tangent to the lower edge of the acetabulum A1C1 and the tangent to the entrance to the acetabulum D1C, and measured from a radiograph in an axial projection (Fig. 1, b) .

Fig.2. Scheme for determining hip joint stability indices (explanation in the text).

7. Vertical compliance angle. The angle formed by the intersection of the tangent to the entrance to the acetabulum (DA) and the longitudinal axis of the femoral neck (BC), open downwards, is called the vertical correspondence angle. X-ray anatomical landmarks for drawing a tangent are the lower pole of the teardrop figure and the outer edge of the roof of the acetabulum. The magnitude of the vertical correspondence angle, which is normally 85-90° in children over 6 years of age, reflects the degree to which the medial inclination of the femoral neck and the downward inclination of the plane of entry into the acetabulum correspond to each other.

8. Degree of bone coverage. On a radiograph taken in the posterior projection, a line (HH1) is drawn from the outer edge of the roof of the acetabulum downward, perpendicular to the line of the U-shaped cartilages (U-U1), and it is determined which part of the head of the femur (¾,⅔,½, etc.) d.) is located medially from this line, i.e., it is covered with the roof of the acetabulum. The normal values of this index for children over 5 years of age are 1-3/4.

An option for determining the degree of coverage is the Wiberg angle, formed by two straight lines drawn from the center of the head: one to the outer edge of the roof, the other perpendicular to the line of the U-shaped cartilages. An angle of at least 25° is taken as the norm. Both of the latter indices are a generalized sign of two different pathological conditions, since their value changes both due to lateral displacements of the femoral head and the discrepancy between the length of the roof of the acetabulum and the diameter of the head. A differentiated indicator of the latter condition is the bone coverage coefficient.

9. Bone coverage ratio. It is the ratio of the vertical diameter of the femoral head (LM) to the length of the roof of the acetabulum, projected onto the line of U-shaped cartilages (EF - the length of the segment of the line of U-shaped cartilages from the bottom of the acetabulum to the Ombredan line): LM÷EF. Normal values of this coefficient for children 3 months old correspond to 2.5, 3 years old - more than 1.3, 4 years old and older - more than 1.1, which means that the length of the roof of the acetabulum is sufficient to completely cover the head of the femur.
The advantage of this indicator compared to the degree of coverage is that it can also be calculated in case of complete dislocation of the femur to predict the state of stability of the hip joint after reduction.

10. Ombredan's sign. (for little ones). A perpendicular descending from the outermost edge of the acetabulum to a horizontal line connecting both Y-shaped cartilages, crossing this horizontal Y-line, divides the hip joint into four parts. Normally, the ossification nucleus of the femoral head is located in the lower inner quadrant, in the case of subluxation - in the outer quadrant under the horizontal Y-line, in case of hip dislocation - in the outer quadrant above the horizontal Y-line (Fig. 2). Before the appearance of the ossification nucleus of the femoral head, the medial protuberance of the femoral neck is taken as a landmark. Normally, it is placed in the lower inner quadrant, in case of subluxation and dislocation - in the lower outer quadrant, in case of high dislocation it is visible on the radiograph in the outer upper quadrant.

The description of prolonged ossification of the junction of the ischium and pubis (synchondrosis ischiopubica) is associated with the name Horvath. The essence of this phenomenon is that during dislocation, the connection of the pubic and ischial bones through cartilaginous tissue lasts longer than normal, and the syndrosis itself is wider. After birth, the normal width of the synchondrosis is approximately 10 mm. In case of dislocation in the hip joint, its width can reach 20 mm. With dislocation, ossification of synchondrosis occurs not at 4-5 years, as is normal, but at 6-7 years. From the point of view of prognosis, the direction and shape of the epiphyseal cartilage of the proximal femur is considered important. A wide, dismembered epiphysis with an indeterminate border and a jagged edge suggests a growth disorder. If the ossification nucleus of the femoral head is located on the lateral edge of the epiphyseal cartilage, then there is a threat of coxa valga formation.

11. Horizontal compliance angle. Reflects the correspondence between the degrees of anterior rotation of the proximal end of the femur and the acetabulum (Fig. 3).

Fig.3. Scheme of spatial relationships in the hip joint in the horizontal plane. Solid lines indicate the longitudinal axes of the necks of the femurs, dotted lines indicate tangents to the entrance to the acetabulum.

Unlike other stability indices, the horizontal compliance angle cannot be directly measured on any radiograph in technically feasible projections. Its value is calculated based on the data of separate determination of the frontal inclination of the acetabulum and the value of anteversion of the proximal end of the femur and represents their difference. For example, it has been established that the angle of frontal inclination of the acetabulum is 60°, and the angle of anteversion of the proximal end of the femur is 35°. The value of the horizontal compliance angle 6udet is 60° - 35° = 25°. If the value of the anteversion angle exceeds the value of the frontal inclination angle, the value of the horizontal correspondence angle is written with a minus sign. The lower limit of the norm is an angle of +20°.

Fig.4. Scheme for determining the stability of the hip joint in the sagittal plane.

Determination of spatial relationships in the sagittal plane is made using a radiograph taken in the sacroacetabular projection (Fig. 6). The state of stability of the hip joint in this plane is assessed by three indicators: the centering of the head in the acetabulum, the angle of sagittal correspondence and the angle of inclination of the roof of the acetabulum.

12. Determining the centering of the femoral head. The longitudinal axis of the femoral neck is drawn (line OO1 in Fig. 4), extended in the cranial direction and tangent to the anterior and posterior edges of the roof of the acetabulum (line AB in Fig. 4). Normally, the longitudinal axis of the cervix intersects the tangent in a section extending from the middle of the cervix to the border of its anterior and middle thirds (points 1 and 2 in Fig. 4). Deviation of the longitudinal axis anteriorly from point 1 or posteriorly from point 2 is a sign of anterior or posterior decentration.

13. Sagittal compliance angle- the angle formed at the intersection of the longitudinal axis of the femoral neck and the tangent to the anterior and posterior edges of the roof of the acetabulum (line AB in Fig. 3). Its normal value is 85-90°.

14. Inclination of the roof of the acetabulum. A horizontal line is drawn from its front edge (line CB in Fig. 3) and the value of the angle formed when it intersects with segment AB is measured. The normal limit for this angle is 12°.

15. Level of intersection of the longitudinal axis of the femoral neck with the roof of the acetabulum(for children in the first months of life). If the femoral neck is insufficiently ossified, the perpendicular restored from the middle of the tangent to the upper surface of the metaphysis can be taken as a basis.

Fig.5. The position of the longitudinal axis of the femoral neck is normal (a), with decentration (b), subluxation (c) and complete dislocation (d).

Due to the invisibility of the medial part of the cervix, which is not yet ossified at this age, on the radiograph, the longitudinal axis of its bony part, and especially the perpendicular to the surface of the metaphysis, occupy a more lateral position in relation to the anatomical axis. Considering this circumstance, The radiological criterion for the correct anatomical relationships in the hip joint in children under 6 months of age is the intersection of the cervical axis with the contour of the roof of the acetabulum at the level of its medial quarter(Fig. 5). A radiological sign of decentration is the direction of the axis of the femoral neck (or perpendicular to the metaphysis) ranging from the border of the medial and next quarter of the roof to the border of the third and last quarter, subluxation - to the lateral quarter of the roof of the acetabulum up to a tangent position to its lateral edge. The intersection of the cervical axis with the lateral edge of the supraacetabular part of the ilium reflects the state of dislocation.

16. Corrections for abduction and adduction of the limb. A change in the direction of the longitudinal axis of the femoral neck or pathological values of the vertical correspondence angle are indicators of hip dysplasia only if the radiograph was taken with a strictly average position of the hips. If there are signs of error in positioning, it is necessary to make a correction for abduction or adduction of the limb (Fig. 6).

Fig.6. Correction scheme for hip placement errors.
α- hip adduction angle; OO1 - position of the axis of the femoral neck during vicious placement; ОО2 is the position of the axis after correction for hip adduction.

The value of the angle of adduction or abduction is measured, and the longitudinal axis of the neck deviates by the amount of this angle during adduction - in the medial direction, during abduction - in the lateral direction.

17. Projection of the longitudinal axis of the femoral neck onto the acetabulum area. With anatomically confirmed correct relationships in the joint, normally, the axis of the femoral neck, when extended in the cranial direction, passes through the U-shaped cartilage. (Fig.2 BC axis).

18. Calculation of physiological deficit. Physiological instability of a child’s joint is manifested by lower normal stability indices than in adults. This difference is designated by the term “physiological deficit.” The magnitude of the physiological deficit normally decreases to zero by 5 years of age. In addition to this, it has been established that ½ of the deficit is covered by the age of one, ¾ by 3 years and the last ¼ by the age of 3 to 5 years.

For example, the vertical compliance angle for a 3-month-old child is 70°. Its normal value for an adult is 85-90°. Hence the magnitude of the physiological deficit is 85° - 70° = 15°. At normal rates of development, ½ of this deficit should be covered by one year of age, and the value of the angle of vertical correspondence should be 77°, i.e. 70° (initial value) + 7° (½ physiological deficit) = 77°. The value of this indicator by the age of one year will be completely different in a child with an initial value of 61°. The magnitude of the deficit is 24°, ½ of it is 12º. 61º+ 12° = 73°, i.e. 5° less than the previous one.

19. Methodology for assessing the rate of coverage of pathological deficits and we will show its interpretation using the example of the angle of vertical correspondence.
The initial value of the vertical correspondence angle for all examples is 53°, from which the value of the pathological deficit is 32°. The assessment is made at one year of age.
Option 1. The vertical compliance angle reached 69° by the age of 1 year. The pathological deficit is covered at the same rate as the physiological one (69° - 53° = 16°; 16° is exactly ½ of the deficit). The prognosis is relatively favorable. Indeed, if the same pace of development is maintained, the index value will reach 77° by 3 years, and by 5 years. 83-85°.
Option 2. The vertical compliance angle reached 73° by the age of one year. The deficit is being covered at an accelerated pace (73° - - 53" = 20", i.e. more than ½ of the deficit). The problem of normalizing joint stability can be considered solved (in this plane!).
Option 3. The vertical compliance angle reached 65° by the age of 1 year. The rate of joint formation remains delayed (65° - 53° = 12°, i.e. less than ½ of the pathological deficit). Residual instability of the hip joint. Indeed, by the age of 3, the value of this index will be equal to only 73° (not half of the remaining deficit will be covered, but, as by the age of one, only ⅜), and by the end of the formation processes the value of the angle of vertical correspondence will not exceed

Chapter 3. Instability of the hip joint.

The state of instability can be a consequence of various pathological changes that determine the nature of its manifestations and severity, and, consequently, the radiographic symptom complex.

The most pronounced manifestation of instability is violation of anatomical relationships. Depending on the degree of their severity, they are defined as dislocation, subluxation and decentration of the head within the acetabulum.

Analysis of the anatomical relationships in the hip joint is carried out using conventional radiographs taken in the posterior or axial or sacroacetabular projections. Based on the posterior radiograph, disturbances in the relationships in the frontal plane (displacement of the femur outward and upward) are determined, according to the other two - in the sagittal and horizontal (displacement anterior or posterior and pathological rotation of the femur around the vertical axis). Dislocations and severe subluxations are diagnosed without much difficulty. Detection of minor subluxations, and especially decentration, presents certain difficulties.

The criteria for normal and pathological anatomical relationships in the hip joint in children do not require complex geometric constructions, provide a differential diagnosis of dislocations, subluxations and decentrations and allow corrections to be made for errors in placement. The position of the longitudinal axis of the femoral neck, extended in the proximal direction, is used as a reference (see Chapter 2). It has also been established that each of the three forms of violation of anatomical relationships corresponds to a strictly defined area, a projection of the proximal end of this axis. With decentrations, the axis is projected onto the medial half of the roof of the acetabulum, with subluxations - onto the lateral half, with complete dislocation, the longitudinal axis of the neck passes lateral to the outer edge of the roof of the acetabulum.

The second most common cause of hip instability is discrepancy between the spatial relationships of its femoral and pelvic components. The amount of bending of the femoral neck does not correspond to the degree of downward inclination and anterior rotation of the entrance to the acetabulum, which reduces the support area for the femoral head.

Features of the spatial position of the proximal end of the femur and the acetabulum are established based on comparison with standard indicators of the values of the neck-diaphyseal angle, the anteversion angle of the proximal end of the femur, the Sharpe angle and the frontal inclination of the acetabulum (see Chapter 2).

A deviation from the normal values of any of the listed angles, taken separately, although it indicates some disturbance in the structure of the hip joint, cannot yet serve as a basis for a conclusion about instability. Moderate deviations from the normal position of one of the components of the hip joint can be compensated by a positive change in the spatial position of the other. Thus, excessive anteversion of the proximal end of the femur can be compensated for by a smaller anterior rotation of the acetabulum than in the average variant of the norm; a more vertical position of the entrance to the acetabulum - increasing the medial inclination of the neck, etc.

A substantiated conclusion about the state of stability of the hip joint can be made only on the basis of determining the values of four so-called stability indices, reflecting the degree to which paired indicators of the spatial position of the proximal end of the femur and the acetabulum correspond to each other:

vertical compliance angle,
degree of bone coverage,
bone coverage coefficient,
horizontal compliance angle. (For the method of determining these angles and indicators, see Chapter 2).

The basis for the conclusion about instability of the hip joint is the identification of the pathological value of at least one of the listed indices.

When measuring stability indices, it is necessary to take into account the position of the pelvis and femur relative to the vertical and horizontal planes of the body. When the pelvis is skewed, the roof of the acetabulum on the side where the tilt occurred “rolls” onto the head of the femur, the position of the roof relative to the axis of the neck becomes more horizontal, as a result of which the value of the angle of vertical correspondence and the degree of coverage turn out to be greater than their true values. The roof of the acetabulum on the elevated side of the pelvis seems to move away from the head of the femur and is located more vertically relative to the axis of the neck, which leads to a decrease in the angle of vertical compliance and the degree of coverage compared to the true ones. Similar situations arise when a limb is adducted or abducted. The first of these positions is accompanied by a decrease in the angle of vertical compliance and the degree of head coverage compared to the true ones, the second is by their increase. If these displacements are present, it is necessary to correct the measurements by the amount of pelvic tilt, hip adduction or abduction measured directly on the radiograph.

Due to the difficulty of obtaining radiographs of the hip joint in the lateral projection, the main object of x-ray functional research is the state of its stability in the frontal plane.

Pathological mobility in this plane (if present) manifests itself most clearly during static loading and during adduction of the limb, since displacement of the femur in the frontal plane is possible only upward and outward. Accordingly, X-rays of the hip joint to identify its instability are performed in three functional positions (standing, lying down with a standard position, and lying down with the limb adducted to the maximum). However, in most cases there is no need to use all three of these provisions. In case of a pronounced violation of the ratios, to determine the degree of displacement of the femur, it is sufficient to produce radiographs in a standard posterior projection and in a standing position. To identify instability of ligamentous-muscular origin, the optimal second position is passive adduction of the limb as it places the greatest demands on the viability of the stabilizing function of the musculo-ligamentous apparatus.

A radiological sign of pathological mobility in the joint along the horizontal axis is the occurrence of subluxations and dislocations, determined by the above-described directions of the longitudinal axis of the femoral neck. In a normally stabilized hip joint, adduction is accompanied by a slightly pronounced decentration, while static load does not have any effect on the nature of the anatomical relationships. Displacement of the femur along the vertical axis is possible only with dislocation or severe subluxation. The severity of this type of pathological displacement of the femur in children can be characterized only approximately - based on changes in the position of the upper pole of the head relative to parts of the ilium. Expressing displacement in linear values is inappropriate, since a displacement of the femur, for example, of 1.5 cm in a child of 3 and 12 years old, due to the significant difference in the sizes of the femur and pelvic bones, will reflect different degrees of pathological mobility.

An X-ray functional sign of instability of the hip joint due to a violation of the stabilizing functions of the ligamentous apparatus is the occurrence of a clear violation of the anatomical relationships in the position of maximum passive adduction of the limb.

An indicator of the severity of any type of instability is the degree of pathological displacement of the proximal end of the femur along the horizontal or vertical axes.

Chapter 4. Congenital hip dislocation

The X-ray symptom complex of congenital hip dislocation has been and is being developed by many researchers. The literature describes a large number of radiological signs and indicators aimed at both identifying congenital hip dislocation and identifying variants of the anatomical structure of the joint that are characteristic of this pathology. At the same time, the diagnostic schemes presented by various authors, calculations of the features of the spatial position and spatial relationships of the femoral and pelvic components of the joint and indicators of disturbances in its development largely duplicate each other, some of them are necessary to solve only highly specialized problems; There are also those that were developed without taking into account the age-related dynamics of joint formation. In addition, determining all the details of the anatomical and functional state of a dysplastic joint is not always necessary.

The proposed method of x-ray examination is based on the general position that its nature and volume must be adequate to the tasks that the doctor has to solve at one or another of the main stages of caring for a child with congenital hip dislocation. These stages are early detection of congenital hip dislocation (as a nosological unit), assessment of the effectiveness of conservative treatment, determination of indications for surgical treatment and choice of methods for its implementation.

The most detailed radiological characteristics of the anatomical and functional state of the hip joint require resolving the issue of the nature of the surgical intervention. The choice of one or another of its techniques is determined by a number of factors: the severity of anatomical changes in the joint, the degree of impairment of supporting and motor functions, the depth of the dysplastic process, etc. The technique of x-ray examination and interpretation of the data obtained should provide the necessary and sufficient amount of information on all of these questions.

According to modern data, the anatomical changes observed in congenital dislocation of the hip are divided into primary, i.e., manifestations of dysplasia of the components of the hip joint, and secondary, developing as a result of the functioning of the joint under pathological conditions.

Manifestations of hip dysplasia, in turn, can be divided into the following main types: pronounced disturbances of anatomical relationships, disturbances in the spatial orientation of the proximal end of the femur and acetabulum, disturbances in the processes of growth and ossification of the bone components of the joint, dysplastic changes in the soft tissue components.

Secondary changes include pathological restructuring of the femoral head, deformation of its cartilaginous model, pathological condition of the cartilaginous limbus and changes in the volume of the articular capsule.

Pronounced violations of anatomical relationships are established based on the analysis of conventional radiographs. Identification of other manifestations of the dysplastic process and secondary anatomical changes requires the use of special methods of x-ray examination and special techniques for interpreting the data obtained. Typical for congenital hip dislocation, disturbances in the spatial orientation of the proximal end of the femur are a greater than normal rotation of it anteriorly (excessive anteversion) and an increase in the neck-shaft angle. Disturbances in the spatial orientation of the acetabulum consist of a decrease in the angle of inclination downwards and a greater than normal rotation of it anteriorly.

Changes in the spatial position of the pelvic and femoral components of the joint cause disturbances in the centering of the femoral head in relation to the acetabulum and create a state of joint instability. The discrepancy between the values of the medial inclination of the femoral neck and the angle of inclination of the entrance to the acetabulum relative to the horizontal causes instability of the joint in the frontal plane, the anteversion angle of the proximal end of the femur and the frontal inclination of the acetabulum in the horizontal plane. The cause of instability of the hip joint in the sagittal plane may be either anterior or posterior displacement of the femur, or an oblique position of the roof of the acetabulum in this plane. (For calculation methods, see Chapter 2).

The normal values of these values are different for different periods of joint formation. In principle, in children of the age that is considered most favorable for surgical treatment (from 2 to 5 years), the spatial positions and spatial relationships of the bone components of the hip joint in the frontal and horizontal planes can be considered impaired when the neck-shaft angle is more than 130°, anteversion more than 40°, Sharpe angle more than 50°, frontal inclination of the acetabulum less than 55º, vertical compliance angle less than 75° for 3 years of age and less than 80-85º for children over 4 years of age, horizontal compliance angle less than 20°.

The state of stability of the hip joint in this plane is assessed by three indicators: the centering of the head in the acetabulum, the angle of sagittal correspondence and the angle of inclination of the roof of the acetabulum (For the method of determining these angles, see Chapter 2). Determining the state of stability of the hip joint in the sagittal plane is important for clarifying the need to change the position or extent of the roof of the acetabulum in the anteroposterior direction during surgery and assessing the results of this displacement.

Violation of the enchondral development of the bone components of the joint with congenital dislocation of the hip can have the following variants, varying in severity:
1) inhibition of the process of ossification of cartilaginous models of the femoral head and acetabulum while maintaining their normal growth rates;
2) inhibition of the growth of cartilaginous models of the femoral head and acetabulum at normal rates of ossification;
3) disruption of the processes of both growth and ossification of the bone components of the hip joint.

When analyzing conventional radiographs, only a general idea of the state of the processes of enchondral development of the bone components of the joint can be obtained based on the fact of inhibition of ossification of the femoral head and an increase in the values of the acetabular index and bone coverage coefficient (for the method of their determination, see Chapter 2).

Unilateral inhibition of ossification of the femoral head is established on the basis of the later appearance of the ossification nucleus or its smaller size compared to a healthy joint. With bilateral dislocation, the rate of ossification can be estimated only approximately by comparison with the average statistical time for the appearance of ossification nuclei (from 6 to 9 months). The approximate assessment is further aggravated by the fact that delayed ossification is not a condition pathognomonic only for congenital hip dislocation, and is observed in a number of systemic diseases (rickets, spondyloepiphyseal dysplasia, myelodysplasia). It should be noted that if rickets can be diagnosed by characteristic pathological changes in the germinal metaepiphyseal cartilages, then spondyloepiphyseal dysplasia in early childhood, especially when its severity is mild, does not manifest itself with any other radiological signs, except for the delayed appearance of ossification nuclei.

An increase in the acetabular index compared to normal variants indicates a violation of the formation of the roof of the acetabulum, but does not allow us to decide whether it is a true bevel or just a violation of the ossification of a normally developing cartilaginous model.

The bone coverage coefficient reflects the degree of correspondence between the sizes of the ossified parts of the femoral head and the roof of the acetabulum and, thereby, the correspondence of the rates of their development. The advisability of introducing this indicator is due to the fact that one of the reasons for the development of subluxations and even dislocations in the hip joint in the postnatal period is recognized to be slower growth of the roof of the acetabulum compared to the growth of the head (for calculation methods, see Chapter 2). The value of this coefficient, firstly, shows whether or not the given extent of the roof of the acetabulum provides reliable support for the head of the femur at a given stage of joint formation, and, secondly, indicates the synchrony or non-synchronism of the rates of ossification. The length of the roof can be considered insufficient, and the synchronization of the rate of ossification is disturbed when the value of the coefficient of bone coverage in children of three years of age is more than 1.3, and 4 years and older - more than 1.1. The values of the bone coverage coefficient do not allow us to resolve the issue of the degree of correspondence between the growth of the femoral head and the roof of the acetabulum and, like the values of the acetabular index, only indicate a violation of the processes of enchondral bone formation.

Secondary anatomical changes in congenital hip dislocation include deformation of the cartilaginous head of the femur, cartilaginous or soft tissue obliteration of the floor of the acetabulum, and pathological changes in the joint capsule, which are visualized on contrast arthrograms.

Typical types of hip dysfunction associated with congenital hip dislocation include instability and limited abduction.

Impaired motor function of the joint is sufficiently revealed during clinical examination. Diagnosis of instability and its type (dislocation, subluxation, disturbances in the spatial relationships of the pelvic and femoral components of the joint) is provided by the methods of x-ray anatomical examination described above (see Chapter 2). Indications for the use of direct x-ray functional examination arise mainly when it is necessary to clarify the volume of pathological displacement of the femur and when deciding whether joint stability can be ensured by correcting the spatial position of the proximal end of the femur alone.

For the method of direct x-ray functional examination of pathological displacement of the femur, see Chapter 2. To solve the second question, x-rays of the hip joint are performed when the hips are abducted at an angle equal to the excess value of the neck-shaft angle with simultaneous maximum possible internal rotation. The resulting radiograph determines the nature of the centration of the femoral head, the magnitude of the angle of vertical compliance and the degree of coverage of the head by the roof of the acetabulum. Normalization of anatomical relationships is considered in favor of the possibility of limiting oneself to one corrective osteotomy of the femur; the preservation of pathological values of these indicators indicates the need, in addition, for plastic surgery of the roof of the acetabulum.

According to all of the above, a detailed radiological characteristics of the anatomical and functional state of the hip joint with indications for surgical treatment of congenital hip dislocation includes the results of an analysis of the following indicators:
1) anatomical relationships in the joint in the frontal and sagittal planes;
2) the magnitude of the vertical compliance angle;
3) the magnitude of the anteversion of the proximal end of the femur and the frontal inclination of the acetabulum and the value of the horizontal compliance angle calculated on their basis;
4) the magnitude of the sagittal correspondence angle;
5) the values of bone and cartilage acetabular indices;
6) the angle of inclination of the roof in the sagittal plane;
7) values of the coefficient of bone and cartilage coverage;
8) position and severity of the cartilaginous limbus of the acetabulum;
9) the presence or absence of cartilaginous or soft tissue obliteration of the floor of the acetabulum;
10) shape and size of the ossified part of the femoral head and its cartilaginous model.

The neck-shaft angle and Sharpe angle are not included in the diagram, since the determination of their values is included in the methodology for calculating the true angle of anteversion and frontal inclination. The need to analyze such a large number of indicators is caused by the variety of variations in the anatomical structure and development of the joint observed in congenital hip dislocation. Thus, dysplasia of the hip joint can manifest itself mainly by disturbances in the spatial orientation and relationships of the proximal end of the femur and the acetabulum with significant disturbances in enchondral formation; pronounced disturbance of growth and development (mainly of the acetabulum) without significant disturbances in spatial relationships, as well as a combination of these pathological conditions. Violations of spatial relationships, in turn, can develop only in one plane (frontal, sagittal or horizontal), in two planes in various combinations and in all three planes, and the cause of these violations can be a deviation from the normal position in only one of any of the bony components of the hip joint, or both. The types of disorders of enchondral bone formation can also vary in the same way. Effective surgical correction of dysplastic structural disorders can be carried out only if all the features of its anatomical and functional state are taken into account.

The X-ray diagnostic technique for congenital hip dislocation in children in the first months of life is determined by the following factors:
1) invisibility on conventional radiographs of the femoral head and most of the roof of the acetabulum,
2) limited indications for the use of special methods of x-ray examination due to the need to minimize radiation exposure, as well as the fact that
3) when determining the intensity and duration of functional conservative treatment, only the severity of the violation of the relationships in the joint is taken into account.

The means of obtaining information is conventional radiography in the posterior projection with a strictly average position of the lower extremities. Interpretation of the data obtained in most cases is limited to identifying violations of the anatomical relationships in the hip joint and classifying them according to their severity. The simplest and at the same time fully adequate indicator is the level of intersection of the longitudinal axis of the femoral neck with the roof of the acetabulum (see Chapter 2).

Considering the difficulty of interpreting conventional radiography data at this age and the comparative frequency of occurrence of various manifestations of hip dysplasia, the value of the vertical correspondence angle is first determined. The landmarks for its construction are the longitudinal axis of the neck (or perpendicular to the upper surface of the metaphysis), the lateral edge of the roof of the acetabulum and the lower pole of the “tear-drop figure” that are clearly visible on the radiograph. Indicators of normal values for this angle in early childhood are much lower than in adults and older children. This circumstance is associated, firstly, with the low ossification of the roof of the acetabulum in both the vertical and horizontal directions, as a result of which the tangent to the edges of the acetabulum, drawn along the bone landmarks, is located more vertically, as well as the presence of so-called physiological instability - failure to achieve the normal orientation of the proximal end of the femur and acetabulum, which is still characteristic of the formed joint. The degree of physiological instability, as well as the rate of ossification of cartilage patterns, are subject to significant individual fluctuations, and therefore, when distinguishing between normal and pathological changes, only the lower limits of normal are used. For the vertical compliance angle in children under 6 months of age, the lower limit of the norm is 60°. The value of the acetabular index can also be used as an additional indicator. However, it should be noted that due to individual variants of the norm, an increase in the values of this index is reliable evidence of dysplasia only with a sharp deviation from normal values or in combination with other changes.

A change in the direction of the longitudinal axis of the femoral neck or pathological values of the vertical correspondence angle are indicators of hip dysplasia only if the radiograph was taken with a strictly average position of the hips. If there are signs of error in positioning, it is necessary to make an adjustment for abduction or adduction of the limb (see Chapter 2).

Identification of pathological values of the vertical correspondence angle is a sufficient basis for concluding about the presence of hip dysplasia and completing the analysis of radiological data. If the value of the vertical compliance angle does not exceed the lower limit of the age norm, then the presence or absence of signs of disruption of the processes of ossification of the roof of the acetabulum is determined based on the bone coverage coefficient. The length of the projection of the bony part of the roof is determined by the method we have already described (see Chapter 2). The dimensions of the cartilaginous head can be determined based on the following calculations. The need to calculate the bone coverage coefficient, as already noted, arises in children in the first months of life only in the absence of signs of disruption of anatomical relationships. This means that the head of the femur is not only located inside the acetabulum, but also relatively correctly centered in it. Since a lag in the growth of the cartilaginous head under normal load conditions is, as a rule, not observed, its dimensions correspond to the dimensions of the entrance to the acetabulum, minus the thickness of the articular cartilage of the latter. The longitudinal size of the head is equal to the length of the tangent to the entrance to the acetabulum, minus 4 mm (total thickness of the articular cartilage of the acetabulum) (according to V.E. Kalenov). An excess of the normal value for a given age of the bone coverage ratio indicates acetabular dysplasia.
Determined by Ombredan's symptom (h).
Thus, X-ray diagnosis of hip dysplasia in children in the first months of life is ensured by determining the nature of the centration of the head in the acetabulum and the values of the angle of vertical correspondence and the coefficient of bone coverage, as well as Ombredan’s symptom.

The magnitude of the anteversion angle of the proximal end of the femur cannot be determined at this age due to incomplete ossification of the neck and the difficulty of taking a radiograph in the axial projection while maintaining strictly correct placement. Therefore, the horizontal compliance angle cannot be determined.

The task of x-ray examination in terms of assessing the effectiveness of conservative treatment is to determine the degree of normalization of the anatomical relationships in the joint and determine the presence or absence of residual instability. Solving the last question in children of the first year of life is associated with certain difficulties due to the variability of the rate of postnatal formation of the joint and, as a result, the approximate average indicators of the norm of angular and linear values characterizing the structural features of the joint. The method we have developed for determining the individual age norm is based on the following physiological pattern. It was previously noted that physiological joint instability is manifested by lower normal stability indices than in adults. This difference is designated by us by the term “physiological deficit.” Based on this, it becomes possible to calculate the appropriate value of any index for a given child (for the calculation method, see Chapter 2).

With hip dysplasia, the deficiency is no longer physiological, but pathological, which excludes the possibility of calculating an individual age norm. The most reliable idea of the state of joint stability in this case is provided by assessing the rate at which the deficit is covered. According to research, the coverage of pathological deficits under the influence of conservative treatment can occur in the same way as physiological ones, at a faster and slower pace. The second of these options can be considered as a sign of the success of the treatment. The interpretation of the effectiveness of the treatment performed in the first option depends on the initial severity of the pathological deficiency. Coverage of the pathological deficit by the age of one year by less than ½ is an undoubted indicator of residual instability.

For the methodology for assessing the rate of coverage of pathological deficits and its interpretation, see Chapter 2.

Bibliography:
1. Conservative treatment of children with congenital dislocation of the hip / N.Kh. Bakhteeva, V.A. Vinokurov, I.A. Norkin, E.A. Petrosova // Bulletin of Traumatology and Orthopedics. - 2003. - No. 4. - P. 34-37.
2. Varus deformity of the femoral neck in children / A.A. Belyaeva, O.A. Malakhov, O.V. Kozhevnikova, S.K. Taranova // Bulletin of Traumatology and Orthopedics. - 1994. - No. 2. - P. 33-36.
3. Our experience in the treatment of congenital hip dislocation in children of different ages / O.A. Malakhov, O.V. Kozhevnikov, I.V. Gribova, S.E. Kralina // Bulletin of Traumatology and Orthopedics. - 2000. - No. 4. - P.26-31.
4. Volkov M.V. Congenital hip dislocation/ M.V. Volkov, G.M. Ter-Egizarov, G.P. Yukina. – M.: Medicine, 1972. – 159 p.: ill.
5. Korolyuk I.P. X-ray anatomical atlas of the skeleton (norm, variants, errors, interpretation). - M.: VIDAR – 1996, 192 p.
6. Reinberg S.A. X-ray diagnosis of bone and joint diseases. - M.: Medicine, 1964.
7. Sadofeva V.I. Normal X-ray anatomy of the osteoarticular system in children. – L.: Medicine, 1990. – 224 p.: ill.
8. Sadofeva V.I. X-ray functional diagnosis of diseases of the musculoskeletal system in children. – L.: Medicine, 1986. – 240 pp.: ill.
9. Traumatology and orthopedics: In 3 volumes / Ed. Yu.G.Shaposhnakova. - M.: Medicine, 1997.
10. Filatov S.V. Early detection and treatment of the most common hip diseases in children and adolescents. – St. Petersburg, SPbMAPO, 1998. – 28 p.
11. Krasnov A.F. ORTHOPEDICS: A textbook for postgraduate doctors and senior students / A.F. Krasnov, G.P. Kotelnikov, K.A. Ivanova. - Samara: Samar. House of Printing, 1998. -480 p.

Pathology of the hip joints occupies an important place among congenital anomalies of the skeletal system. From 2 to 4% of children are born with underdevelopment of osteochondral elements, which is called dysplasia. And if changes in the hip joint are not detected in time, then as you grow older, problems with walking and other manifestations arise that interfere with normal life.

Diagnostic measures to identify structural abnormalities in the hip joint are represented by imaging studies. And given the high prevalence and accessibility, the first of them is radiography. This method has already become firmly established in medical practice, including for diagnosing osteoarticular pathologies in childhood.

General information

The hip joint is the largest joint in the human body. It is formed by the head of the femur and the acetabulum (acetabular) cavity of the pelvic bone. A cartilaginous lip is attached along the edge of the latter, which increases the area of contact between the articular surfaces. Thanks to the spherical shape, movements in all axes are available for the hip joint:

Flexion and extension.
Adduction and abduction.
External and internal rotation.

The joint is abundantly surrounded by ligaments and muscle tendons, which, along with their own capsule, strengthen and stabilize it, protecting it from excessive mobility. But this is only possible with the correct development of all structural components.

In young children, even normally, the hip joint is not sufficiently developed, i.e., its biomechanical immaturity is present. This is confirmed by the flattening and more vertical position of the acetabulum, and the excessive elasticity of the ligamentous apparatus. And with dysplasia, these phenomena develop into structural disorders that interfere with the normal physical development of the child.

After birth, it is necessary to identify structural abnormalities in the hip joint in time, because the further development of the baby depends on this.

The essence of the technique

The study is based on the ability of body tissues to absorb x-rays to varying degrees. Hard tissues, which include bones, absorb them to a greater extent, while soft tissues, on the contrary, pass them through better. The image is obtained by projection onto a special film, which is locally “exposed” in proportion to the power of the radiation flux. There are also digital devices in which registration is performed on a photosensitive matrix, and the result is generated in electronic form. But the image can be printed on paper if necessary.

Advantages and disadvantages

An X-ray examination of the hip joint can be performed at any medical institution - from a district clinic to a large interregional center. The widespread use of the method is due to its obvious advantages:

Availability.
Ease of implementation.
Good visualization of bone structures.
Low cost.

However, despite this, radiography also has some disadvantages that make it not the best study that currently exists. The disadvantages of the procedure include:

Radiation load on the body.
Inability to assess joint function (static image).
Lower information content compared to tomography.
Does not allow determining the condition of soft tissues (without contrast).

In most cases, the advantages outweigh the disadvantages. Even the potential harm of X-rays has been greatly exaggerated. Numerous studies have proven that additional risk can only appear at doses exceeding 50 mSv per year. And when examining the hip joint, the radiation exposure to the body is in the range of 0.5–1 mSv. Modern digital devices require even lower radiation power, almost comparable to the normal background radiation.

Considering the above, parents should not worry about possible radiation exposure when performing an X-ray of the hip joint in an infant. In acceptable doses, the study is practically harmless, but late diagnosis of dysplasia has much more serious consequences.

Despite certain disadvantages, X-ray examination in children is in many cases considered as the method of choice.

Methodology

An X-ray of the hip joint is indicated if dysplasia is suspected in children after 3 months of age. Before the examination, no special preparation is required - it is only important to remove all metal objects from the child’s body or clothing. An important condition for obtaining an informative result: the baby must be in a position with straight legs. To achieve this, special fixing elements are used that eliminate incorrect installation and extraneous movements. The procedure itself takes no more than 5–7 minutes. During this time, parents should stay outside the X-ray room to avoid unnecessary radiation exposure.

results

The resulting images must be evaluated by a radiologist and an appropriate conclusion must be provided. The following auxiliary lines allow you to correctly interpret the image and make a diagnosis of hip dysplasia:

Median - through the center of the sacrum.
Hilgenreiner - through the lower edges of the iliac bones.
Shenton's - through the edge of the obturator foramen, continuing to the inner surface of the femoral head (arcuate).
Perkin - through the outer upper edges of the cavity.

If the Hilgenreiner line is crossed by a tangent drawn along the roof of the glenoid cavity, an acetabular angle or index is formed. It is very important in identifying dysplastic disorders and determining their degree. The magnitude of this angle depends on the age of the child:

Newborn: 25–30 degrees.
4–6 months: 21–26 degrees.
7–9 months: 20–25 degrees.
1 year: 18–22 degrees.
2 years: 17–21 degrees.
3–4 years: 15–18 degrees.

Thus, by the age of 5, the acetabular angle should normally be less than 15 degrees, and in children at the age of 14 it reaches 10 degrees. In addition to the condition of the acetabulum, it is necessary to evaluate the proximal (upper) part of the femur. In healthy children, the head is centered relative to the acetabular surface. This means that the angle formed by the femoral neck and a line drawn through the edges of the socket is straight. And the shape of the proximal femur is closely related to it. Normally, the neck-shaft angle should be 126–135 degrees. This indicates the correct installation of the lower limb. Radiologists also evaluate other angles:

Vertical deviation (31–35 degrees).
Vertical compliance (70–90 degrees).
Antetorsion (20–30 degrees).
Viberga (more than 20 degrees).

In addition to the presented indicators, the values of vertical and external displacement of the articular head are taken into account. If the image shows no deviations in the relative position of the structures of the hip zone, but there is only a slight bevel of the acetabulum and a delay in the formation of ossification nuclei, then they speak of initial dysplasia. The next stage of the pathology - subluxation - is accompanied by partial displacement of the head, an increase in the acetabular and cervical-diaphyseal angles. And a dislocation is indicated by complete separation of the articular surfaces with a displacement of the axes of the limb.

The results of x-rays of the hip joints in children should be assessed by an experienced specialist, which will exclude both under- and over-diagnosis of dysplasia.

Alternative research methods

Ultrasound is also the method of choice for diagnosing hip dysplasia. Its advantage is that acoustic waves do not provide radiation exposure and allow one to assess the condition of cartilage tissue, which at an early age has not yet had time to be completely replaced by bone. Ultrasound is used for suspected dysplasia in children under 3 months of age, as well as for anyone who has contraindications to taking an x-ray.

During the examination, the image is displayed in such a way that it looks like a vertical slice through the center of the joint. The doctor determines the shape and position of the edge of the acetabulum, the condition of the cartilage, and how well it covers the femoral head. Alpha and beta angles (the inclination of the bony and cartilaginous part of the acetabulum, respectively) are assessed.

If we talk about computed tomography, it is not performed on children due to high radiation exposure. But magnetic resonance imaging is possible because it is carried out without ionizing radiation. In this case, the accuracy of the result is much higher than with X-ray or ultrasound methods.

Thus, X-ray of the hip joint is a method that is widely used for diagnosing various pathologies and primarily congenital dysplasia. It is quite accurate and informative, but, unfortunately, it is not without its drawbacks. However, the latter are not so serious as to become an obstacle to diagnosis, because timely detection of the disease is already half the success.

Hip joint and its pathologies

The hip joint is the junction of the pelvic bone, into the socket of which the femur fits with its head. The socket of the joint is a hemispherical socket called the acetabulum.

Joint structure

The anatomy of the hip joint is quite complex, but it also provides quite wide possibilities for movement. The edge of the socket of the pelvic bone is formed by fibrous cartilage tissue, which is why the socket acquires its maximum depth. The total depth of the depression is greater than a hemisphere due to this rim.

The inside of the socket is lined with cartilage tissue formed by hyaluron, where the socket is located close to the cartilage covering the head of the femur. The remaining part of the surface inside the cavity is covered with loose connective tissue, which covers the lower part in the area of the opening of the cavity and the central depression in the cavity. On the surface of the connective tissue there is a synovial membrane.

A rim of cartilage fibers along the edges of the socket, called the labrum, fits snugly against the head of the femur and holds the bone in place. In this case, the lip continues with the transverse ligament. Under this ligament there is a space filled with loose connective tissue. Vessels and nerve endings pass through the thickness, which are directed to the femoral head and pass into the head itself through the fibers of the ligament.

The joint capsule is attached to the pelvis posterior to the lip. The capsule is very durable. It is subject to mechanical stress only when great force is applied. The femoral neck for the most part enters the articular capsule and is fixed in it.

The iliopsoas muscle is attached to the capsule in front. In this area, the thickness of the capsule is minimal, so 10-12% of people may develop a bursa filled with synovial fluid in this area.

Articular ligaments

The structure of the hip joint also includes a system of ligaments. The femoral head ligament is located inside the joint. The tissue that forms the ligament is covered with a synovial membrane. The fibers of the ligament contain the vessels of the circulatory system and go to the head of the femur. The depression (small depression) in the central part inside the glenoid cavity is the area where the ligament begins. It ends in the fossa of the head of the femur. The ligament is easily stretched even if the femoral head prolapses from the acetabulum. Therefore, although the ligament plays some role in the mechanics of joint movement, its importance is small.

The strongest ligament in the entire human body belongs to the hip joint. This is the iliofemoral ligament. Its thickness is 0.8-10 mm. The ligament begins from the anterior inferior spine of the iliac wing and ends on the intertrochanteric line of the femur, fanning out towards it. Thanks to this ligament, the thigh does not bend inward.

Thanks to powerful muscles and strong ligaments on the front surface of the hip joint, the vertical position of the human torso is ensured. Only these parts of the joint ensure that the femoral bones of the torso and pelvis balance on the heads of the femurs in a vertical position. Inhibition of extension is provided by the developed iliofemoral ligament. Movement in the direction of extension can be performed a maximum of 7-13 degrees.

The ischiofemoral ligament is much less developed. It runs along the back of the joint. Its origin is the area of the ischium involved in the formation of the acetabulum. The direction of the fibers of the ligament is outward and upward. The ligament intersects with the posterior surface of the femoral neck. Partially the fibers forming the ligament are woven into the articular capsule. The rest of the ligament ends at the posterior edge of the greater trochanter of the femur. Thanks to the ligament, the inward movement of the hip is inhibited.

From the pubic bone the ligament runs outward and backward. The fibers are attached to the lesser trochanter of the femur and are partially woven into the articular capsule. If the hip joint is in an extended position, then it is this ligament that inhibits hip abduction.

Collagen ligament fibers, called the circular zone, pass through the thickness of the joint capsule. These fibers are attached to the middle of the femoral neck.

Physiology of the joint

The movement capabilities of a joint are determined by its type. The hip joint belongs to the group of nut-shaped joints. This type of joint is multi-axial, so movement in it can have a variety of directions.

Movement with maximum scope can be made around the frontal axis. The frontal axis passes through the head of the femur. The swing can be 122 degrees if the knee joint is flexed. Further movement is inhibited by the anterior wall of the abdomen. Extension of the hip joint is possible no more than 7-13 degrees from the vertical line. Further movement in this direction is limited by stretching of the iliofemoral ligament. If the hip moves further backwards, this is ensured by the curvature of the spine in the lumbar region.

Movement around the sagittal axis ensures abduction and adduction of the hip. A movement of 45 degrees is made. Next, the greater trochanter rests on the wing of the ilium, which prevents movement to a greater extent. It is possible to abduct the hip 100 degrees in a bent position, since in this case the greater trochanter turns backward. Around the vertical axis, the thigh can move 40-50 degrees. To make a circular movement with your leg, you must move around three axes simultaneously.

The hip joint allows movement of the pelvis, not just the hips. That is, the movements of the body relative to the hips take place in the hip joint. Such movements are performed during various actions. For example, if a person walks, then at certain moments one leg stands and serves as a support leg, and at this time the pelvis moves relative to the thigh of the supporting leg. The amplitude of these movements depends on the anatomical features of the skeleton. The following factors influence it:

femoral neck angle;
size of the greater trochanter;
size of the wings of the ilium.

These parts of the skeleton determine the angle between the vertical axis of movement, which passes through the head of the femur to the fulcrum in the foot, and the longitudinal axis of the femur. This angle is usually 5-7 degrees.

Moreover, if a person stands on one leg and balances on this fulcrum, the lever mechanism is activated, the upper arm of the lever - from the top of the greater trochanter to the iliac crest - becomes greater than the distance to the thigh from the ischium. The pull towards a greater distance will be stronger, so in the position on one leg the pelvis will shift towards the supporting leg.

Due to the larger size of the upper lever arm in the female skeleton, a female swinging gait develops.

What does a hip x-ray show?

An x-ray of the hip joint allows you to visualize the contours of the edges and floor of the acetabulum. But this is possible only at the age of 12-14 years. The compact plate of the acetabulum is thin on the fossa side, and thick on the bottom side.

The neck-shaft angle depends on the age of the patient. For newborns, the norm is 150 degrees, for children aged 5 years - 140 degrees, for adults - 120-130. The image clearly shows the contours of the femoral neck, the greater and lesser trochanters, and the structure of the spongy substance. Quite often, radiographs of the hip joint in elderly patients reveal calcification of the labrum.

Causes of pain in the hip joint

Pain in the hip joint can indicate not only directly the pathology affecting this part of the musculoskeletal system. Painful sensations here may indicate pathologies of the abdominal organs, reproductive system, and spine (lumbar region). Quite often, pain in the hip joint can radiate to the knee.

The causes of joint pain are divided into the following groups:

injuries;
anatomical features and diseases of local origin (joint, its ligaments, surrounding muscles);
radiating pain in diseases of other organs and systems;
systemic diseases.

Traumatic damage to the hip joint can take the form of a dislocation, bruise, or sprain. This group of causes of pain includes fractures of the pelvis, the femoral neck in the area of the greater and lesser trochanters of the femur, and stress fractures (or stress fractures) in the same areas.

It also requires the most complex treatment and long-term rehabilitation. Pain can be caused by a ruptured labrum, partial or complete ruptures of muscle fibers, sprained muscles and ligaments, and hip dislocation. Traumatic lesions also include APS syndrome and APC syndrome.

Diseases and pathological changes that cause pain in the hip joint include:

osteonecrosis of the femoral head;
coxarthrosis;
bursitis (trochanteric, iliopectineal, sciatic);
femoroacetabular impingement syndrome;
formation of free intra-articular bodies;
snapping hip;
piriformis syndrome;
tenosynovitis and tendinitis;
proximal syndrome;
osteoporosis.

Pain may radiate to the hip joints due to diseases of other organs and systems:

neuralgia;
inguinal hernia;
diseases of the spine;
sports pubalgia.

Systemic diseases that cause pain in the hip joint include all types of arthritis, leukemia, infectious lesions of the hip joint, Paget's disease.

Also, joint pain can be a sign of primary or secondary cancer. Osteomyelitis is one of the likely causes of pain. Often pain is caused by a complex of reasons, since many of the pathologies of the hip joint can be interconnected.

There are some specific causes of hip pain in childhood:

juvenile rheumatoid arthritis;
epiphysiolysis;
Still's disease;
Legg-Calvé-Perthes disease, etc.

The hip joint bears serious loads and is involved in almost any movement of the body, so its condition must be taken seriously. If pain occurs, it is recommended to immediately contact the clinic for diagnosis. Most often, an x-ray is prescribed for diagnostic purposes.

The human thigh is one of the large structures of the musculoskeletal system, taking on part of the function of upright posture. It consists of muscles and tendons that attach to the femur. Large blood vessels pass through the thigh, including the femoral artery, as well as nerves - the genitofemoral, femoral and others. The femur articulates with the rest of the skeleton at the acetabulum (above) and the patella (below). When your hip hurts, most often the cause of the pain is either muscle or bone tissue.

Major diseases

In addition to injuries to soft tissues and bones, pain is often caused by various processes in the bones. Sometimes the pain radiates to the thigh due to pathologies of the spine (osteochondrosis, spondylosis). To find out the cause of the pain, it is necessary to observe the nature of the painful sensations, their intensity, as well as the reaction to the load on the hip and changes in the position of the limb. Pain in the hip can be sharp, dull, aching, cutting - depending on the situation.

Soft tissue injuries

Mechanical damage is the most common cause of pain in the hips. Impacts and mechanical injuries refer to damage to the soft tissues of the thigh, accompanied by ruptures of blood vessels and nerve endings. In this case, the skin can remain intact, while an area of hemorrhage forms under it.

Soft tissue bruise of the thigh

The injury occurs as a result of falls or blows. This diagnosis is characterized by the following features:

type of pain - dull, aching, aggravated by pressing on the damaged surface, the motor ability of the limb is preserved;
localization of pain - one-sided, at the site of injury;
additional symptoms include the formation of a hematoma (a blue-violet, irregularly shaped area that appears as a result of the rupture of small blood vessels under the skin).

A bruise is diagnosed during an examination, and sometimes an x-ray is taken to rule out a fracture. If the bone is intact and there is a hematoma, the doctor diagnoses “bruise of the soft tissues of the thigh.” In most cases, treatment of a bruise is not required, because healing of damaged tissue occurs on its own without the need for outside help. But in some cases, the help of a surgeon or traumatologist is required if the injury is severe and an extensive hematoma has formed in its place. In this case, a large volume of blood in the subcutaneous and intermuscular space can compress neighboring nerves, causing pain. The doctor opens the hematoma using a medical instrument and removes the blood.

Hip sprain

A sprained hip ligament is a complete or partial rupture of small fibers of ligament tissue, which occurs as a result of disproportionate physical activity (during sports, lifting weights), falls, slips, sudden changes in body position or heavy load without prior preparation (warm-up). Children and adolescents with underdeveloped muscle structures, as well as older people with osteoporosis, are most often susceptible to such injuries.

Main signs of sprain:

type of pain - acute, intensifying when trying to move the leg;
localization of pain - in the hip joint, one-sided, over time “spreads” along the thigh towards the lower leg, less often radiates to the lower back;
additional symptoms are swelling at the site of injury, hyperemia of the skin over the injured area.

Sprain of the hip ligaments is diagnosed during examination and palpation. An orthopedic doctor or traumatologist moves the patient’s limb in different directions and asks the patient to perform simple exercises, and, based on successful completion, makes a preliminary diagnosis. The final diagnosis is made using an x-ray, which usually shows joint deformity.

Treatment of injury involves applying a fixing bandage that limits the mobility of the limb. Further therapy depends on the degree of ligament damage. With the relative preservation of the integrity of the ligamentous tissues, conservative treatment is carried out (taking anti-inflammatory and analgesic medications, ensuring rest). As the ligaments are restored, exercise therapy is prescribed, aimed at restoring the functionality of the joint. For complete ligament rupture and/or avulsion fracture, surgery is performed.

Bone injuries

Fractures are another cause of hip pain. They also occur as a result of rough mechanical impact - shocks, falls, sudden compression, improper load distribution and other factors.

Often pain occurs due to a hip fracture, especially in people over 65 years of age. Aging is usually accompanied by osteoporosis - increased fragility of bones, and even with light loads the integrity of the bone can be compromised. Typically a fracture occurs as a result of a fall.

Symptoms of a fracture include:

the nature of the pain is acute;
localization of pain - in the upper thigh with irradiation to the groin;
additional symptoms are rotation of the foot outward relative to the knee, limited mobility of the leg, inability to walk and stand.

Damage is diagnosed using x-rays and MRI of the joint. You can also determine a femoral neck fracture by tapping or pressing on the heel: the patient will experience unpleasant and even painful sensations.

Treatment of a hip fracture can be quite difficult, especially in old age. Plaster application does not have an effect, so the victim is prescribed surgical intervention - osteosynthesis (fixation of joint fragments with metal screws), as well as endoprosthetics (full or partial joint replacement).

Pertrochanteric femoral fracture

This type of fracture is also most common in women over 65 years of age, and occurs as a result of falling on the side (while walking on a slippery surface in winter, with sudden movements).

This diagnosis has the following symptoms:

the nature of the pain is strong, very sharp;
localization - in the area of injury in the upper thigh;
additional symptoms are “stuck heel syndrome,” in which the patient cannot lift an outstretched leg while lying on his back.

Accurate diagnosis is only possible based on radiography. Treatment of a pertrochanteric fracture today is practiced in the form of surgery, in which the bone is pinned and fixed in the correct position. The operation allows you to quickly recover from injury, and the procedure itself is minimally invasive (a small incision is made) and lasts about 20 minutes.

Soft tissue inflammation

Often the thighs on the outside of the soft tissues hurt not because of mechanical damage, but because of the inflammatory process occurring in the soft tissues.

Myositis

One of the causes of pain in the soft tissues of the thigh is myositis, which occurs due to hypothermia, injury, infectious or autoimmune processes, when the body begins to perceive tissue cells as foreign and attack them. The patient feels pain of moderate intensity due to weakening of the thigh muscles.

The disease is diagnosed based on a survey, examination, and a blood test that detects eosinophilic leukocytosis. A soft tissue biopsy is also performed.

Treatment of myositis is complex:

ensuring rest (bed rest);
diet correction (strengthening the diet with vitamins and mineral complexes).

Depending on the cause of the disease, treatment is carried out with antibiotics (for infection), immunosuppressants and glucocorticosteroids (for an autoimmune cause), non-steroidal anti-inflammatory drugs, physiotherapy and massage (if the doctor allows).

Trochanteritis is an inflammation of the tendons that connect the lesser and greater trochanters to the femur. Most often, the pathological process occurs due to injuries, due to hypothermia or overload. The pain is aching, pressing, aggravated by exertion (walking, climbing stairs), hypothermia. Localization of unpleasant sensations is in the outer side part (“breeches”).

The disease is also diagnosed through examination and questioning, blood tests, X-rays or MRIs of the hip.

Treatment is conservative and involves the use of non-steroidal drugs. In more complex cases, injections of glucocorticosteroids into the tendon area are prescribed, which are done once every 2 weeks. Physical therapy is also prescribed, less often laser therapy, massage with rubbing of anti-inflammatory ointments.

Inflammatory bone lesion

The bones and joints of the hip are also susceptible to negative factors leading to pathological processes that cause pain.

Coxarthrosis

The main symptom of coxarthrosis is pain in the groin, radiating to the outer front and side of the thigh, and less often to the buttock and knee. Both joints or just one can hurt. It becomes difficult for the patient to move the limb, especially to the side. A crunching sound is heard in the joint, and the leg may look slightly shorter than the other.

Coxarthrosis is diagnosed using radiography (the image shows an increase in the neck-diaphyseal angle, dysplasia or changes in the proximal part of the femur).

Treatment of the disease:

conservative, at an early stage - with the help of anti-inflammatory drugs, chondroprotectors, intra-articular steroid injections, warming ointments,
surgical - if the hip joint is severely damaged, endoprosthetics (replacement) is performed.

Aseptic necrosis is very similar in symptoms to coxarthrosis, but is characterized by high pain intensity, which becomes unbearable as the pathological process develops. The disease begins due to the cessation of blood supply to this part of the joint; the process itself proceeds quickly and is accompanied by severe night pain. Characteristic for this disease is the age of the patients: most often it affects men from 20 to 45 years old, while women are 5-6 times less likely to suffer from it.

Diagnosis of hip joint disease is carried out using modern research methods - X-ray and MRI. An experienced doctor can make a diagnosis based on symptoms and examination of the limb, but ultimately everything is decided by an X-ray examination of the joint and bone.

Therapy consists of restoring nutrition to the femoral head. Non-steroidal and steroidal agents, chondroprotectors and calcium preparations are also used to accelerate the restoration of damaged bone tissue.

When should you contact a specialist?

Depending on the type and intensity of pain, as well as other signs, the patient can cope with the problem on his own or seek help. Since the hip is an important part of the body, responsible for the ability to walk, pain in it should not be ignored. The location of large arteries and veins is another reason why extreme close monitoring is necessary.

Warning signs that require you to see a doctor as soon as possible:

sharp and acute pain that makes leg movement impossible;
crunching and clicking in the joints and the bone itself when moving;
extensive hematoma accompanied by edema;
uncharacteristic position of the leg relative to the axis of the body.

These symptoms indicate a serious hip injury or dysfunction that requires medical attention.

First aid at home

In case of serious hip injuries, especially fractures, it is important to provide timely assistance to the victim even before the doctor arrives. The limb must be immobilized by placing a splint on it. It is important to provide rest to the injured leg. If the pain is severe, ice or other cold objects may be applied, but a heating pad or other heat sources should not be used. In case of severe unbearable pain, the victim can be given an analgesic, and then constantly monitor his condition, not leaving him alone until the ambulance arrives.

Conclusion

Injuries to the bones and soft tissues of the hip, as well as pathological processes in the bones, tendons and joints are the main factors in the occurrence of pain. Even if it does not prevent a person from going about his business, there is no need to let the situation take its course and self-medicate. This can lead to worsening of the inflammatory process, after which longer and more complex treatment will be required. In case of fractures and bruises, professional medical assistance is simply necessary, otherwise it is fraught with lifelong limitation of limb function as a result of improper healing or a chronic inflammatory process.

Acetabular angle or index is a radiographic term for measuring hip joint deformity. The concept was first introduced by scientists Kleinberg and Liebermann in 1936. Normally, the acetabular index of the hip joint in newborns is less than 28 degrees. The indicator changes with age. By the end of the first year of life it drops to 22 degrees or less. Deviations from generally accepted standards indicate the presence of pathology in the child: dysplasia, dislocation, subluxation. Timely detection of the disease will prevent its further development and maintain the health of the joint.

Angles of the hip joint and their norms in children

Measuring the angles of the hip joint in children is carried out if congenital dysplasia is suspected. Timely medical care saves many from disability in adulthood, because dysplasia is a disorder in the formation of joints. Mostly girls suffer from it as a result of improper intrauterine development, frequent swaddling, and lack of vitamins and minerals. The exact reason has not yet been established.

Transverse scanning is carried out to determine the direction in which the femoral head is displaced in an unstable position (dislocation, subluxation). An X-ray sensor is placed in the area of the greater trochanter of the femur.

In the neutral position, the normal angle is 15-20 degrees. The rounded head of the femur is located in the acetabulum, the Y-shaped cartilage is in the central part. In front is the pubic bone, and in the back is the ischium.

To analyze a cross-section in a flexed hip position (about 90 degrees), the sensor is installed in the projection of the acetabulum and femoral head. Normally, the head should be completely immersed in the recess and not move during dynamic tests. In the picture, the joint looks like the Latin letter “U”. With subluxation, the image will more likely resemble the letter “V”, and with dislocation, it will resemble the letter “L”.

Sagittal angle the correspondence is formed at the intersection of the longitudinal neck of the femur and the tangent to the anterior and posterior edges of the roof of the acetabulum. The indicator is measured using an x-ray in the sacroacetabular projection. Additional factors that are taken into account when determining joint stability:

centering of the head in the acetabulum;
angle of inclination of the roof of the acetabulum.

If the x-ray was taken with the hips in an average position, then any changes in the direction of the longitudinal axis of the femoral neck or pathological angle values are a sign of dysplasia.

To eliminate errors in installation, it is enough to make corrections for abduction and adduction of the hips.

Weisberg angle or central-border is formed by a vertical straight line and a line running from the center of the femoral head to the lateral side of the acetabulum.

In the medical system vertical-central corner called the VCA angle. It is formed by a straight line (V) and a line running from the center of the femoral head through the anterior edge of the shadow of the femur behind the anterior edge of the glenoid cavity. X-rays are taken in the “false profile” position. The patient is in a standing position, and the cassette of the device is located behind the limb being examined. The angle between the pelvis and the cassette should be 65 degrees, and the distance to the bone should be 110 cm. To obtain an image, the beam of rays is directed to the center of the femoral head. The side view can be rotated 25 degrees.

Second title Hilgenreiner angle- angle of cartilage. It is measured using a radiograph. The plane lies between the limbus and the transverse plane of the pelvis. The value allows you to determine the ossification of the hip bone. Delayed bone formation is another sign of congenital dysplasia.

The neck of the hip joint is one of the elements of the proximal articular end of the femur. In good condition corner femoral neck rotation around its axis is 20-25 degrees.

With the diaphysis, the femoral neck forms neck-shaft angle(SHDU). Normally, in newborns it is 140-150 degrees, and with age it decreases to 120-130 degrees. Pathological forms are considered to be an obtuse angle, which is formed as a result of a varus or valgus pelvis, and individual, constitutional features.

Sharpe angle(DCB) is the angle of inclination of the acetabulum in the vertical plane. It is formed by a horizontal line passing through the upper and lower edges of the acetabulum. To assess the indicator, a frontal radiograph is used. Using a photo you can measure:

inclination of the depression in the vertical plane;
depth of the glenoid cavity;
length of the cavity entrance;
glenoid coefficient.

Vertical compliance angle called the part of the plane that is formed by crossing the tangent to the entrance to the acetabulum and the longitudinal axis of the femoral neck.

The reference point for the tangent (DA) is the lower pole of the teardrop figure and the outer edge of the roof of the acetabulum.

The normal angle for children over 6 years old is 85-90 degrees.

Additional diagnostic lines

In addition to angles, radiologists often use the concept of lines. These data help determine the relationship between the femoral head and the acetabulum and identify pathology.

Lines used in the diagnosis of the hip joint:

Shenton line. It is carried out along the lower contour of the femur. It passes to the lower contour horizontally to the surface of the pubic bone. Forms a smooth arched line. With dysplasia, it has a broken shape.
Calvet line. Crosses the outer contour of the ilium and goes to the upper contour of the femoral neck. With dysplasia it also has a broken structure.
Ombredant-Perkins line. It follows vertically from the superior-outer point of the acetabular notch and continues with the longitudinal axis of the femoral diaphysis. With normal development of the musculoskeletal system, the proximal epiphysis is located inward from this line, in pathology - outward.
Keller line. A horizontal line passing through both Y-shaped cartilages.

Lines are necessary for a schematic representation of the elements of the hip joint. A deviation from the norm will allow you to easily determine the presence of a displacement and its degree.

Dependence of angles on the age of the child

After birth, children regularly undergo preventive examinations by an orthopedist. An increase in the acetabular index with age increases the risk of pathology of the femoral head. However, at an early stage of improper formation of the musculoskeletal system, the disorder can be corrected without surgery in a short time.

Table of normal hip joint angles in children by month:

3-4 months	25-30 degrees
5-24 months	20-25 degrees
2-3 years	18-23 degrees

If the angle is 5 degrees greater than normal, a subluxation is diagnosed, if the angle is 10 - dislocation, and more than 15 - high dislocation.

Definition and classification of normal angles in children

In children, the norms of the angles of the hip joint are classified depending on the diagnostic method used for measurement. Ultrasound is suitable for children up to 6 months, as it is completely harmless. An x-ray is prescribed to confirm the diagnosis and obtain more accurate information about the condition of the joint.

The advantage of ultrasound is the assessment of indicators in real time. In particular, the ultrasonic method measures:

Alpha angle. The measurement technique is very similar to calculating the acetabular index. The normal value is 60 degrees or more.
Angle beta. Formed by the main line and lip of the triradial cartilage. The norm in children does not exceed 77 degrees.
The degree of coverage of the head with the roof of the acetabulum. In newborns and preschoolers it reaches 50% and higher.

X-ray allows you to assess the symmetry of the hip joint and determine the relationship between the proximal epiphysis and the pelvic bones at the stage of formation. The main indicators that are used for this:

Hilgenreiner line;
Perkin line;
acetabular angle;
Shenton line.

The Hilgenreiner and Perkin lines are perpendicular to each other. The first runs along the upper contour of the triradial cartilages in the horizontal plane. The second crosses the lateral contour of the roof of the acetabulum. The upper epiphysis should be located in the lower medial quadrant.

Children with a high risk factor for dysplasia are recommended to visit an orthopedist once every six months or according to an individual schedule prescribed by a doctor. During this period, you should engage in physical therapy and make full use of the capabilities of the hip joints.

Use special backpacks, slings, car seats. In them, the child’s torso takes the correct position and is not deformed.
For newborns, special wide swaddling techniques are used. They can be mastered at courses for expectant mothers or at a consultation with a pediatrician or orthopedist.
Massage or lightly exercise your baby regularly. Knead all joints and bones by performing flexion, extension, rotation and abduction movements.
To securely fix your baby’s legs, discuss with your doctor an orthopedic device, for example, Pavlik stirrups.

Swimming lessons, visiting a gymnastics group, breathing techniques, and children's yoga are also suitable for prevention.

However, the listed parameters may vary on an x-ray, and this must be taken into account so as not to make an erroneous diagnosis.

The main signs of Dysplasia on a radiograph should be considered the following:

The Norberg angle is less than 105 degrees.

B. The index of insertion of the femoral head into the socket is less than 1

Wide and uneven joint space.

Incongruity in the joint.

D. The cervical-diaphyseal angle is more than 145 degrees.

The parameters are taken from both joints and entered into the certificate of the condition of the hip joints.

Dysplasia is divided into stages based on quantitative accounting of simultaneously identified radiological signs (Mitin V.N., 1983) (Table 2).

When assessing the stages of the process, only true signs of dysplasia are taken into account and radiological signs of secondary arthrosis are not taken into account.

To bring this classification of DTS dogs into line with the classification of the International Canine Federation, you should use a summary table (Table 3).

Comparative characteristics of the parameters of a normal joint and those with DTS on a radiograph

Table 2

Options		Pathology
Norberg angle	105 degrees or more	Less than 105 degrees.
Index of insertion of the femoral head into the socket, units	Equal to one. The joint gap is narrow and uniform.	Less than one. The joint space is widened and uneven. Incongruence in the joint
Tangential	Always negative or zero	Positive, with a rounded anterior outer edge of the acetabulum
diaphyseal angle	Equal to 145 degrees.	More than 145 degrees.

Table 3

X-ray characteristics of different stages of hip dysplasia in dogs

Stages of the disease	Changes on the X-ray
Healthy joint	None
Stage of predisposition to dysplasia	Presence of one sign
Pre-dysplasia stage	Presence of two signs
Stage of initial destructive changes	Presence of three signs
Stage of pronounced destructive changes	The presence of four signs, subluxation in the joint is possible
Stage of severe destructive changes	The presence of four signs, the Norberg angle is less than 90 degrees, dislocation or subluxation in the joint

DIFFERENTIAL DIAGNOSTICS

Pain and lameness in themselves do not allow us to confidently draw a conclusion about hip dysplasia, especially if the lameness is possibly localized in one of them. In addition, lameness due to DTS not n permanent, does not appear in all cases and also depends on the stage of DTS and the changes caused by it. After all, dogs experience a gradual transition from a normal, healthy state of the hip joint to the most severe form of DTS. The clinical signs of dysplasia, which does not occur in a clear classical form (with all the clinical signs inherent in it), are similar to the signs of some other diseases, among which it should be noted destruction of the femoral head (aseptic necrosis), fracture of the femoral neck, dislocation and subluxation of the hip joint. Therefore, differential diagnosis from these diseases is necessary.

Destruction of the femoral head (aseptic necrosis), is associated with a violation of its blood supply, which over time leads to destruction of the hip joint. The disease is most typical for puppies of small breeds (Toy Poodle, Toy Terrier, Fox Terrier, Pikinese, Japanese Chin, etc. SCH at the age of 4-10 months, as a rule, of a genetic nature, and almost never occurs in large breed dogs. Whereas DTS is a disease of large breeds of dogs. On the radiograph, with destruction of the femoral head, the acetabulum and angles do not change, but only resorption of the femoral head is noted.

Femoral neck fracture A is a pathology of the hip joint that occurs suddenly and is usually associated with the influence of an external force. With this lameness, support on the injured limb is not possible. The diagnosis is confirmed by x-ray.

Dislocation The hip joint arises from the influence of an external force and is accompanied by a complete impossibility of support, while the diseased limb is shortened in comparison with the healthy one. Making a diagnosis is not difficult^

Subluxation hip joint may occur S. gradually but in large breed puppies as a result of weakness of the ligamentous apparatus. -Most often occurs during a period of intensive growth - from 4-10 months. It differs from DTS in that, as a rule, one limb is affected (the opposite joint is not changed in shape). At the same time, the configuration of the femoral head and the angles of the acetabulum are preserved. Without timely treatment, this pathology can lead to arthrosis hip joint.

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Based on the MSCT performed, no significant differences were identified by gender or between the right and left hip joints in healthy children; the obtained values of the neck-shaft, acetabular angles, vertical deviation angle, vertical compliance and Wiberg angle are comparable with the X-ray data and have less error. We have developed a technique for measuring the antetorsion angle, sagittal compliance and frontal inclination in the axial projection. The obtained data are not comparable with radiography data, which may be due to the need for complex mathematical transformations in the latter (Table 5). X-ray non-contrast structures of the hip joint are well visualized with MSCT, which made it possible to assess the condition of the cartilage, capsule and muscles of the hip joint.

Our study revealed that early contact (up to 3 months) with an orthopedist for hip dysplasia occurred in 41% of cases, in the first month of life – in a few patients. However, in the second half of life the diagnosis was made initially in 7% of cases.

Clinically, the most common signs were limited hip extension and asymmetry of the subgluteal popliteal folds (more than 70%).

According to ultrasound examination from the lateral approach in children with preluxation in B-mode, an oblique position of the roof of the acetabulum was recorded; deformed short cartilaginous protrusion. Lateralization of the femoral head at rest and during provocative tests; the angle was 55-60, the angle was 45-75. The echographic picture of the subluxation was characterized by the presence of a rounded bony protrusion. During provocative tests, slight lateralization of the femoral head was recorded; corner<45°, угол >75°.

In the case of hip dislocation, the femoral head was decentered. The deformed short cartilaginous protrusion did not cover the femoral head. All patients with hip dysplasia had a delay in the formation of ossification nuclei.

When analyzing the results of the study from the anterior approach, it was revealed that the most sensitive is the echographic sign of the ratio of SCR/PPM. In children of group 2, this indicator did not differ from the norm in any case. In children of group 3, it changed only when the diagnosis was made after 6 months. In all examined children of group 4, the ratio of GFR/PPM increased. In addition, in children of group 4, when the diagnosis was made late, the joint capsule was thinned and stretched (p<0,05). По нашему мнению это может свидетельствовать о формировании торсионных изменений бедренной кости.

In all children of groups 2, 3 and most children of group 4, the circumflex vessels of the femur were identified. The exception was 2 observations of group 4, in which the correct course of the circumflex vessels was not determined; they were represented by separate color signals. The diameter of the circumflex vessels in children of groups 2 and 3 did not differ significantly from the normative values. Children have 4 groups up to 3 months. vessel diameters did not differ significantly from normative values (p<0,05), у детей старше 3 мес. диаметр сосудов уменьшался.

In group 2 of patients, the cervical artery, vessels of the growth plate, round ligament and capsule of the hip joint were identified in 100% of cases. In group 3, these vessels were identified only in 74% of children. Significant changes were determined in children of group 4. When diagnosis is made in the first 6 months. life, blood flow in the head of the femur was weakened, cervical arteries were detected in 100% of cases. In patients of the 2nd half of the year, the vessels of the growth plate and round ligament were not identified; blood flow in the cervical vessels was determined in 26.6% of cases. Apparently, changes in blood flow may be associated with changes in individual components of the hip joint and their spatial relationships. On the other hand, in some cases there may be a vicious development of the vascular system.

Using pulsed wave Doppler in the circumflex vessels, we identified various variants of hemodynamic parameters.

In children of the 2 groups, the first three months of life did not differ significantly from the age norm. In children older than 3 months of group 2, a statistically significant increase in the peripheral resistance index and systolic arterial blood flow velocity was determined; decrease in diastolic blood flow velocity and venous outflow velocity. The diameters of the vessels were not changed. Such changes could be associated with insufficient blood supply, but the possibility of its perception from the capillary bed and adequate venous outflow.
Some children in group 3 showed a decrease in velocity indicators in the circumflex arteries. Indicators of peripheral resistance did not change in them. We regarded such changes as minimal and indicated the consistency of metabolic processes. Another type of hemodynamic changes in this group of patients was characterized by preservation of speed indicators and an increase in peripheral resistance in the circumflex arteries. The rate of venous outflow in them decreased significantly. In the area of the round ligament, growth plate and cervical vessels, hemodynamic parameters decreased. We interpreted such changes as a decrease in perfusion in the femoral head, which could lead to ischemic processes in it.
The most diverse types of hemodynamic disorders were detected in children of group 4.

In subgroup 1, in the circumflex vessels, the velocity parameters and resistance index were reduced; which could indicate insufficient blood flow due to vasoconstriction.

In subgroup 2, systolic velocity and peripheral resistance index exceeded the age norm; venous outflow rates were reduced, which may have been due to a violation of the spatial relationship of the components of the hip joint and possible tension of the vessels. Probably, the volumetric blood flow exceeded what it should have been, creating pronounced venous stagnation in the head of the femur.

In patients of subgroup 3, the systolic velocity in the circumflex arteries and the resistance index were significantly reduced; diastolic and venous outflow velocities increased. We regarded such changes as a “gaping” capillary bed, which led to rapid outflow of blood and ischemia of peripheral areas. In addition, a significant increase in the rate of venous outflow could indirectly indicate the inclusion of blood shunting processes and an even greater deterioration of the microcirculation state.

In the area of the round ligament, growth plate and cervical vessels in children in the first six months of life, hemodynamic parameters decreased. After 6 months the vessels of the growth zone and round ligament were not identified. The identified changes, in our opinion, indicated an aggravation of the processes of ischemia of the femoral head.

When radiography was performed in children of group 2, an increase in the acetabular index to 32°-33° and a bevel of the bony protrusion of the acetabulum were noted. In children of group 3, partial decentration of the femoral head, flattening of the acetabulum, an increase in the acetabular angle to 32°-38°, an increase in d value to 18 mm, a significant delay in the appearance of ossification nuclei, and the Calvet and Shenton arches were disrupted were revealed. In children of group 4, the head of the femur was completely decentered and located outside the acetabulum; the ossification nucleus was not identified. The ossification nucleus of the ilium was underdeveloped, which caused a sharp bevel of the bony protrusion and the transition of the line of the acetabulum into the line of the iliac wing. The acetabular index was significantly higher than normal, more than 370-40°. The distance d increased by more than 25 mm, and the value h decreased to 3-5 mm. The Calvet and Shenton arcs were broken.

Dynamic observation of children in groups 2-4 was carried out for 1 year. In children of group 2 already after 3 months. from the start of treatment in B-mode, ossification nuclei of varying degrees of severity appeared, but symmetrically on both sides; almost horizontal direction of the acetabulum; stability of the femoral head during provocative tests. When studying hemodynamics, all indicators corresponded to the normative values. In no case were negative dynamics identified.

Table No. 5

Morphometric angular parameters in healthy children

Groups	1-3 years(n=28)		3-7 years(n=32)		7-15 years(n=36)
Angles	CT	R	CT	R	CT	R
Frontal projection
Cervical-shaft angle	137.1±0.4	136.8±0.67	132.4±0.3	132.56±0.7	130.1±0.35	129.8±0.78
Vertical angle	49.0±1.2	48.85±1.8	46.9±3.5	47.1±3.47	45.1±1.3	46.6±3.8
Vertical compliance angle	78.5±4.4	78.9±5.2	88.2±3	87.3±3.2	94±1.78	93.59±2.4
Acetabular angle	30±5.3	31.3±4.7	20.1±2.8	20.7±3.4	14.6±3.7	12.6±4.1
Wiberg angle	16.5±4.1	18±3.8	21.3±2.2	20±4.2	29.3±2.9	26±3.6
Axial projection
Antetorsion angle	18.0±2.6	26.9±8.7	16.4±5.2	24.6±7.2	14.8±3.7	23.5±5.9
Horizontal compliance angle	64.7±3.6	25±7.6	65.4±3.5	24.9±4.64	62.0±5.1	26.2±8.2
Frontal inclination angle	52.8±5.2	38±2.1	57.1±4.7	39.1±5.87	65.3±4.2	38.4±6.1
Sagittal projection
Sagittal compliance angle	58.8±5.6	82±2.4	60.8±4.4	86±3.7	67.2±5.2	91±3.5
Head alignment	Avg. third		Avg. third		Avg. third
Inclination of the roof of the acetabulum	31.0±1.3	14.6±2.8	30.6±2.5	14.3±1.9	29±2.8	12.5±2.0