Developmental dysplasia of the hip is an abnormal development of the hip where the ball part doesn’t stay firmly in place above the femur, or thigh bone. When a baby is being examined during a well-baby check-up, the physician usually moves the baby’s hips around and this is what the physician is looking for. In some children, the joint may be just a little loose, but in others, it can be worse. As well, as the child gets older, the ligaments may loosen even more.
What researchers don’t understand is if the child isn’t having pain early in life, what causes the pain to appear as the child reaches his or her teens? For this reason, the authors of this article studied the intraarticular pathology, how the hip appears inside the joint, in teens (adolescents) who have this problem.
Researchers studied 22 patients (23 hips in all) with arthroscopy, surgery that uses very small incisions and allows surgeons to insert long narrow instruments with a camera. Using the camera and instruments, surgeons can perform repairs that used to only be done with a large incision.
Fourteen patients (14 hips) had a history of developmental dysplasia as young children. Eight of them had been treated with the Pavlik harness, a harness that is fit to the baby or child and holds the hip or hips in the correct position. They were used on the children for between three to 12 months. This system didn’t work for four patients who ended up having surgery to fully correct the problem. Two were diagnosed and treated at age 12 and 15 months. Eighteen hips were pre-arthritic, five were in the early stage.
After the researchers looked at the hips using arthroscopy, they found that there was degeneration or deterioration of cartilage in all of the affected hips and highest in almost 78 percent of the pre-arthritic hips. In most of the hips, over 72 percent, the damage was seen in the acetabulum, the part of the hip that is the hollowed out area covering the head of the femur, making the ball-and-socket joint. Of the damage in the acetabulum, more than half was at the top front part.
The researchers also found in the pre-arthritic hips that most had labral tears, which are tears in the cartilage that line the hip joint and provide protection between the bones. For the adolescents who had early arthritis, their tears were worse than those who had pre-arthritis.
All these findings led the researchers to conclude that there is a high rate of deterioration in adolescents who have developmental dysplasia of the hip, even in the pre-arthritic stage, not just in the early arthritis stage.