What is Hip Dysplasia?

Hip dysplasia is a developmental condition where the hip is dislocated at birth. It is not necessarily congenital as it can have causes that are separate from any anomaly that comes from the genes. The condition can affect one hip or both hips.

What children are at risk for hip dysplasia? There is a small population that is at risk for congenital hip dysplasia. Most babies probably fall into the category of being born in breech position. The baby is pulled out butt or legs first and that can result in a hip dislocation. Also, babies can suffer from positioning issues within the womb that can lead to development problems like hip dysplasia and club foot.

In infants, hip dysplasia is not readily noticeable. Babies normally keep their legs tight into their body when they cry, go to the bathroom and play. Unless baby is trying to stand up it is hard to detect any problems. This is why doctors examine infants to see if they are having any hip problems.

A child with a dislocated hip bone will have a click when the leg is moved in certain positions. This “click” is felt rather than heard. To determine the extent of the hip dysplasia an x-ray has to be performed to see the entire joint. One method of classification is the Crowe classification method.

In a normal hip, the head of the femur fits into the socket (acetabular) joint on the pelvis. With hip dysplasia, the first rating is a normal joint where the socket is well formed and the femoral head fits and moves without clicking.

Level II involves a femur head that doesn’t fit exactly in the socket joint. The joint may be too wide, having less of a defined curve to hold the femur in place. This is classic dysplasia.

The joint can even go so far as to not even have contact with the femur head in level III. The upper portion of the socket is minimal or missing so the femoral head moves upward. Where it makes contact with the pelvis, movement forms a false acetabulum above where it should be.

In the most severe incidents, level IV, the femur is floating. The socket is poorly formed and the femoral head rides high above the joint.

Treating hip dysplasia involves the baby wearing a sling device called a Pavlik harness. Once the joint has been reduced, the harness is placed so that the hip grows into the proper position as cartilage is replaced with bone. This works for most babies diagnosed before six months of age. Older children are placed in a spica cast to restrict movement and ensure proper alignment.