What is Hip Dysplasia?
Hip dysplasia refers to congenital defects in the structure of the hip joint and consists in its underdevelopment, as a result of which secondary coxarthrosis is formed over the years. This malformation, according to R. Ya. Gorbunova et al., Is detected in 0.54-1.5% of newborns.
It has been established that the formation of a hip joint development defect occurs during fetal fetal development as a result of a number of endogenous and exogenous factors (heredity, elderly parents, endocrinopathy in the mother, infectious diseases, vitamin deficiency, prenatal pathology – threatened miscarriage, pregnancy toxicosis, pathological labors , increased radioactive background, etc.).
Pathogenesis during Hip Dysplasia
In hip dysplasia, the following changes are found: the joint capsule is stretched, resulting in some degree of dislocation of the femoral head, underdevelopment of the ligaments, flattening of the acetabulum, which has a geometrically regular globular femoral head.
The above discrepancy between the congruence of the articulating surfaces of the hip joint during development of the child is fixed and leads to the fact that during walking the supporting capacity of the hip joint is impaired. The latter experiences a greater load per unit area of both articulating surfaces than a normal joint. This circumstance determines the development of degenerative changes in cartilage in the defective joint, i.e. secondary coxarotrosis.
Anatomical defects of the hip joint are the result of segmental tissue inferiority, the severity of which determines the degree of dysplasia. With significant hip dysplasia, the femoral head may be in a state of subluxation and even complete anatomical dislocation. In such cases, we should talk about congenital subluxation and dislocation of the hip joint.
Currently, great importance is attached to the organizational aspects of the problem of hip joint dysplasia, since its early detection contributes to the successful cure of this malformation. MV Volkov emphasizes the importance of diagnosing hip dysplasia in the first days after the birth of a child, which should be examined in the maternity hospital not only by a midwife, but also by a pediatric orthopedic surgeon.
Symptoms of Hip Dysplasia
The clinical signs of this pathology are the asymmetry of skin folds on the thighs, detected during examination from the front and back side, restriction of passive hip abduction outwards and backwards when the child is on the back and bent knee and hip joints. Normally, the number of skin folds on both legs is the same, leg abduction is possible up to an angle of 80-90 °. In dysplasia, passive abduction is limited to 50-60 °, while the doctor may feel some resistance due to springy resistance of the thigh muscles on the affected side.
A reliable sign of hip dysplasia is a symptom of a click. The symptom is checked in the position of the child on the back. The legs are bent at the hip and knee joints at an angle of 90 °. The hands of the researcher cover the knee joints so that the first fingers lie on the inner surfaces of the knee joints of the child, the index fingers in the area of the greater spits, the rest of the fingers on the outer surface of the thighs. The doctor fixes one leg, and the other determines the presence of a clicking symptom, exerting pressure along the axis of the thigh. Next, this leg is taken outwards and backwards at an angle of 50-60 ° and the index finger is pressed on the big spit; in dysplasia, a clicking sound is heard again. In the same way, examine the other leg.
The symptom of the click is due to the slippage of the lumbosacral muscle from the front surface of the femoral head, which does not fully enter the acetabulum. A click symptom can be detected within the 1st week of a child’s life with hip dysplasia. After a week, this symptom disappears. Of the indirect signs of hip dysplasia, other manifestations of the congenital pathology of the osteo-articular system can be taken into account. These include the softness of the bones of the skull (craniotabes), torticollis, polydactyly, flat-pawed varus or valgus foot installation. Sometimes in a child with hip dysplasia, the reflexes characteristic of the neonatal period (search, sucking, cervicotonic) are disturbed.
In doubtful cases, especially when diagnosing mild degrees of hip dysplasia, an x-ray examination of the pelvis is useful, the results of which are evaluated by an experienced radiologist.
Diagnosis of Hip Dysplasia
When a diagnosis of hip dysplasia is established, it is necessary to begin a conservative functional treatment with various types of diverting tires that impose (in the position of maximum leg retraction) for periods from 3-4 months to a year or more. During functional treatment, a periodic radiographic examination is performed periodically, with the help of which they establish the correctness of the anatomical relationship of the bones of the pelvis and thigh, the center of the femoral head in the acetabulum.
During the maximum abduction, the stretched capsule of the hip joint is reduced, which further ensures the full development of the hip joint.
Diagnosis of hip dysplasia at a later age is based on clinical symptoms of impaired gait (toeing inward, mild lameness – in case of unilateral lesion; swinging from side to side, duck gait – in bilateral lesion, and especially in subluxations or dislocations of these joints).
In adults, complaints of patients with fatigue in the leg, a feeling of instability of the hip joint after a long walk, and pain syndrome as a sign of secondary coxarthrosis, which is confirmed by clinical X-ray examination, are the reason for the diagnosis of dysplasia. In such cases, complex treatment using physical therapy, massage, resort factors, as well as surgical interventions such as variational (valgization) osteotomies with the creation of a roof of the acetabulum in order to increase support for the femoral head are necessary.