Our four-year old has been treated conservatively for the last three years for a hip problem called developmental dysplasia. It didn’t work. Now he has a squashed hip joint and loss of blood supply to the top of the thighbone. Doctors are doing more testing. What’s likely to happen?

Interruption of the blood supply to the bone is called ischemia. This must be treated right away or the bone can start to die, a process called necrosis. Usually surgery is the next step.

The surgeon will reform the angle of the bone so that the top of the femur (thigh bone) fits into the socket. Sometimes it’s necessary to build a little bridge or cap over the edge of the socket to keep the bone in place. The operation is called an osteotomy for short or the full name: derotational valgus osteotomy.

The results of this operation are usually very good. The changes made help restore the leg length and allow the muscles to function normally again. Many children are able to walk without a limp. Later in life mild arthritic changes may occur. Studies show much more involved arthritis for those who don’t have this surgery.