Childhood hip dysplasia describes a condition where the hip’s ball (femoral head) is dislocated from the socket (acetabulum). Treatment options include bracing, casting, and surgery but the exact course of treatment is dependent on the patient’s age and the severity of their condition.
Childhood hip dysplasia occurs as a result of developmental problems in the hip joint. The condition occurs when the femoral head partially or completely slips out of the hip socket causing dislocation of the hip joint. Severity of the condition ranges from a partial dislocation (subluxation) to a complete dislocation where the ball has no contact with the socket.
Childhood hip dysplasia ranges from mild to severe and can affect one or both hips. It is more common in girls and usually affects the left hip. Dislocations in some infants may not cause pain until the child begins to walk.
Common symptoms of childhood hip dysplasia:
- Abnormal positioning or turning of the legs
- Decreased range of motion on the side where the hip is dislocated
- The leg may appear shorter on the side where the hip is dislocated
- Skin folds on the thigh or buttocks may appear uneven
- A limp if one hip joint is affected or waddle if both hip joints are affected. However, an abnormal gait might be difficult to detect if both hips are dislocated.
The exact cause of childhood hip dysplasia is unknown but several factors are believed to play a contributing role:
- Abnormal position of the femoral head
- A shallow or abnormally shaped acetabulum
- Laxity or looseness of the ligaments around the joint
- Large fetal size, narrow uterus, and/or breech position of the fetus leading to abnormal stress on the hip joint
- Improper swaddling or overly restrictive baby seats and carriers where an infant’s legs are abnormally positioned
Newborn exams should include screening for early detection of hip dysplasia. This is especially important if the baby was born in a breech position or has a family history of hip dysplasia. Physical maneuvers and tests involving the hips, legs, and knees are used to detect instability, limited range of motion, and skin unevenness in the hips. Ultrasounds, x-rays and MRI scans may be ordered to confirm the diagnoses if any of these tests are positive for hip dysplasia. Treatment should begin immediately if the child is found to have hip dysplasia.
Barlow & Ortolani Tests
During the Barlow test, an infant is placed on its back, the leg is then brought towards the middle of the body with a 90 degree bend at the knee and light pressure is applied to the knee. Hip dysplasia may be present if this maneuver allows the femoral head to be easily dislocated from the socket. The Ortolani test verifies the occurrence of hip dysplasia by applying pressure to the upper outer thigh bone (greater trochanter) to gently relocate the hip. These tests are performed from birth until about the age of 3 months.
The Galeazzi test is performed on children over the age of 3 months. The infant is placed on its back with the knees together and the ankles touching the buttocks. The height of the knees is then observed and hip dysplasia may be present if the knees are found to be unlevel.
The aim of treatment is to keep the femoral head in good contact with the acetabulum. A brace or harness can often be sufficient if the condition is detected within six weeks of birth. If the problem persists, casting may be advised to keep the hip in flexion and abduction. Surgery should only be advised after all conventional non-surgical treatments have proven ineffective.
Pavlik Harnesses, van Rosen Splints, and abduction braces are utilized for infants to reduce dislocated hips, maintain reduction of a previously dislocated hip, or to encourage the hip socket to deepen and conform around the ball of the femoral head. When applied and utilized correctly, these devices are effective in over 90% of cases, allowing most patients to avoid surgery.
Surgical Treatment Options for Moderate Hip Dysplasia By Age
2 month – 18 months
- Placement of the ball in the socket without any incisions (closed reduction) and a body cast
- A small tendon release in the groin and casting
- Opening of the hip joint from inside the groin (medial open reduction)
- Opening of the hip joint from the front (anterior open reduction)
18 months to 6 years
- Anterior open reduction with or without deepening of the socket (Innonimate Salter or Dega Osteotomy)
- Shortening or redirecting the femur (femoral osteotomy or shortening)
6 years +
- Past the age of six, treatment is usually for shallow and misaligned hips, not dislocated hips. The goal of treatment is often to deepen the socket or realign the femur.