congenital coxa vara
Introduction
Introduction to congenital hip varus Congenital hip varus, also known as developmental hip varus, is a deformity caused by progressive reduction of the femoral neck dry angle in young children. Normal adult neck angle is 120 ° ~ 140 °, children 135 ° ~ 145 °, if the neck dry angle is less than 120 °, called hip varus. It is one of the common reasons for children to behave in a day. There was more unilateral incidence than bilateral, and there was no significant difference in gender and ethnicity. basic knowledge The proportion of illness: 0.005% Susceptible people: young children Mode of infection: non-infectious Complications: congenital hip abduction contraction and pelvic tilt scoliosis
Cause
Congenital hip varus
(1) Causes of the disease
The cause of congenital hip varus is unknown, and many factors may be related to its pathogenesis. Some people think it is a growth disorder, which belongs to a type of incomplete development of the proximal femur; some people think it is caused by trauma; others Emphasis is related to endocrine; it may also be related to family inheritance.
(two) pathogenesis
In the fetal development stage, the proximal femoral condyle extends to the upper end of the femur, which is characterized by a crescent-shaped cartilage column, which is quickly divided into the epiphyseal part of the femoral neck and the epiphyseal part of the greater trochanter. The medial part of the femoral neck matures earlier, causing the femoral neck to become deformed. Long, and the epiphysis of the femoral head will have an ossification center at 6 months after birth. When the femoral head and neck cartilage are damaged, the lesion is formed by fibrous tissue instead of normal endochondral ossification. The plate breaks and disappears, often in the form of a separate triangular bone. As the child walks with weight, it gradually develops into a hip varus.
Prevention
Congenital hip varus prevention
The disease is a congenital disease, no effective preventive measures, early diagnosis and early treatment is the key to the prevention and treatment of this disease. There are non-physiological shear stresses and variable stresses between the femoral head and the femoral neck in patients with congenital hip varus. The principle of treatment is to reduce the bending stress in the child's growth period to reach normal or near normal, and to change the femoral head with The shear stress between the necks is a physiological compressive stress.
Complication
Congenital hip varus complications Complications Congenital hip abduction contraction and pelvic tilt scoliosis
Pelvic tilt and scoliosis can occur, and the development of the disease can cause the greater trochanter to protrude outward, and the femoral neck can be inverted to form a shortening of the limb.
Symptom
Congenital hip varus symptoms Common symptoms Fatigue joint pain, weakness, hip varus, lower extremity abductor gluteal muscle atrophy
The most prominent manifestation of this disease is the increasing aggression. The symptoms are not obvious in infants. The early stage is mainly hip pain. After the limb is weak, it is easy to fatigue. When walking, the body is shaking, limp, when standing, the affected limb is externally rotated and light. Intra-degree position, pelvic oblique to the affected side, scoliosis deformed in the spine, convex to the affected side in the lumbar region, convex to the healthy side of the thoracolumbar region, the affected side of the gluteal muscle atrophy, the hip line is lower than the healthy side, Trendelenburg sign positive When the patient is in the supine position, the hypertrophic femoral head can be reached in the groin, the neck, the large culmination apex is higher than the Nelaton line, the hip abduction, the internal rotation and the extension are obviously restricted, and the nesting test is negative.
Examine
Congenital hip varus examination
X-ray examination, the neck dry angle is progressively reduced, the femoral head sacral line changes from horizontal to vertical, and there is a triangular bone block separated by a fissure at the proximal femoral head of the femoral neck, and two translucent bands pass through the femoral neck to form "Y"-shaped fissures, as the bone grows, the varus becomes more and more obvious, and the acetabulum changes adaptively. The degree of hip varus can be assessed by measuring the HE angle, which is the double acetabular "Y" shaped cartilage The angle at which the line intersects the extension of the femoral head slab is normally 25°.
Diagnosis
Diagnosis of congenital hip varus
diagnosis
If there is knee pain in children with hip pain, lower extremity abduction, internal rotation and extension are obviously limited, this disease should be considered, combined with the characteristics of X-ray film, the diagnosis is not difficult.
Differential diagnosis
1. The history of osteochondrosis osteochondrosis, hip activity limitation and limb shortening are similar to mild congenital hip varus, but both have their own characteristics on the X-ray film, osteochondral femoral head There is no separation of the neck, the head is dense and flat, and the neck is short and thick.
2. Congenital dislocation of the hip in patients with congenital dislocation of the hip occurred earlier, starting from early childhood, the femoral head was seen outside the acetabulum, most patients were positive for the nesting test.
3. This disease and childhood secondary osteophyte spondylolisthesis, avascular necrosis of the femoral head, femoral neck osteomyelitis, multiple osteochondral dysplasia, femoral neck fracture and other causes of hip varus are different, but all have a limp gait.
