A B C D E F G H I J K L M N O P R S T U V W

DEVELOPMENTAL DYSPLASIA - CONGENITAL HIP DISLOCATION

What is Developmental Dysplasia ?

Congenital dislocation of the hip may be present at birth when the ball of the baby's thigh bone (femur) is dislodged from its socket in the hip bone (dislocation). This is not a painful condition and unless the baby is examined specifically for dislocation it may not be apparent that the hip is dislocated until the child begins to walk. Occasionally, dislocation occurs in the period after birth. It may affect one or both hips.

How does Developmental Dysplasia occur ?

Pregnant mothers secrete a substance in their bloodstream which allows their ligaments to become lax, which helps the baby to be delivered through the pelvis. Some of this substance enters the baby's blood and makes the baby's ligaments lax. This allows the baby's hip to dislocate. Abnormal position in the womb may cause the hip to dislocate. Conditions which affect the muscle balance around the hip also cause dislocation.

Why does Developmental Dysplasia occur ?

The condition affects one to two babies in every thousand. It is more likely if the child is born to parents who have had a dislocated hip, is a firstborn female, or is born bottom-first (breech delivery). It is also associated with other birth defects such as club foot, and certain other conditions affecting the mother during pregnancy.

Treatment Involved for Developmental Dysplasia

The most important factor in treating hip dislocation is that it should be detected early. Because of this, babies are examined at birth, before discharge from hospital, at 6 weeks and at subsequent post-natal checks. If detected early, the majority of children may be successfully treated by the use of a special splint or harness. This harness places the hip in its socket and holds it there. Your child will wear this for 6 12 weeks until the ligaments tighten and the hip stays in its socket. In a few babies, splinting is unsuccessful and in these cases an anaesthetic is needed to replace the hip. A special plaster (frog plaster) is then applied to hold it in place. In a few cases where this treatment does not work, and in cases where the dislocation is found late, it may be necessary for the child to have an operation to replace the hip. This operation may work on its own, but some cases may require bony operations on the pelvic bone and/or thigh bone to ensure that the hip remains in its socket. After such operations plaster treatment is required for up to 6 months, followed by a harness for a further period. When these are removed, physiotherapy may be required to encourage your child to move.

During Treatment for Developmental Dysplasia

During the use of harnesses or splints your baby will grow. Because of this, a regular check will be made in the clinic to ensure that they do not become too tight. If this happens, the harness will need to be changed. Your surgeon will tell you how much movement is allowed and whether your child can spend any time out of the harness after the initial phase of treatment. Plaster treatment involves a large plaster around the lower body and both legs, with a hole cut to allow the baby to pass urine and empty the bowels. It is important that the plaster is kept as dry as possible to prevent the baby developing a severe nappy rash. If the plaster becomes wet or a rash develops, it may need changing. Occasionally the edge of the plaster will rub on the skin and cause a plaster sore. Should this happen, the plaster may need trimming or changing. If a child in plaster remains unhappy for more than 24 48 hours, then advice should be sought as there may be a problem with the plaster. Occasionally when a plaster has been on for a long time, the child's bones become thin and when they start to walk they may sustain a small fracture of the thigh bone. This is not serious and is treated with a small splint until it heals.

After Treatment for Developmental Dysplasia

It is usual for the surgeon to follow up your child at regular intervals after treatment for a dislocated hip. This will continue after splint or harness treatment until your child is walking and an x-ray shows that the hip is developing normally. It is usual to observe children who have had the hip reduced surgically until they are adults. In the early stages, unequal leg lengths and abnormal positions of the limb should be watched for. If these occur, advice should be sought.

If Developmental Dysplasia is Left Untreated

If a dislocated hip is left untreated, the hip remains out of its socket whilst the child grows. Because of this, the normal socket does not develop properly and a new shallow socket may form higher up on the pelvic bone. If only one hip is dislocated, the child will develop a painless limp when it walks. However, in time early arthritis will develop in the abnormal hip joint and cause pain. If the condition affects both sides, the limp is not so noticeable but the child may have a waddling gait . The progress when both sides are affected is the same as one side, but both hips may become affected by early arthritis and eventually develop pain.

Effects on Family of Developmental Dysplasia

During treatment in a splint, harness or in a plaster, your child will be surprisingly mobile. However, they will need help in moving about. Special trolleys may be of help. Otherwise, aside from being an inconvenience, your child will usually develop normally given a supportive family environment.