Upcoming Summer 2016

Periacetabular Osteotomy (PAO) for Acetabular Dysplasia

That huge title is part of the surgery that Noah will facing this next summer, 2016.  Recent MRI results showed pretty much what the surgeon thought... the hip socket is too flat, the femoral head is too big and there are grooves in the bones where there shouldn't be.  Without this corrective surgery, Noah would develop severe hip problems in his 20s, most likely resulting in the need for a hip replacement.  With this corrective surgery, the outlook is good, and it wouldn't be until about his 50s that he might need a hip replacement. 

Figure 1 shows a normal hip.  Figure 2 shows a hip similar to Noah's.  (Note: These are not Noah's x-rays.)

The surgery itself would be in two parts.  The first is the PAO portion.  This is most commonly used to treat acetabular dysplasia or a "shallow hip socket."  A dysplastic hip has incomplete or inadequate coverage of the femoral head.  The dysplastic hip is more "dish shaped." 

Because of the inadequate coverage of the femoral head in a dysplastic hip, the weight across the hip is distributed on a smaller surface area resulting in excessive load along the rim of the hip socket. Over time, this increased load along the rim of the socket will lead to degeneration of joint cartilage and formation of osteoarthritis. Patients with this condition frequently seek medical attention due to activity-related hip pain (discomfort in the groin or side of the hip). Prolonged sitting or walking can also increase these symptoms and a sensation of catching or popping may also occur. As these symptoms continue to increase, a slight limp may be noticed and more strenuous activities may become difficult.  Noah already has a slight limp again, partly because his left leg is 1 cm longer than the right leg.

In case you didn't know, "Periacetabular” means around the acetabulum (hip socket). “Osteotomy” means to cut bone. Therefore, PAO means to cut the bone around the acetabulum and reposition the hip socket. At surgery, controlled cuts are made to loosen the acetabulum from the pelvis, and the acetabulum is repositioned.  An incision is made across the front of the hip joint to allow exposure of the hip and surrounding pelvis. The use of x-ray during surgery helps direct the bony cuts and confirm the correct reorientation of the socket. The acetabulum is fixed in the new position with three or four screws. In most uncomplicated cases the surgery takes two to three hours.  However, Noah's bones don't like to do that they are supposed to do, so he needs part two of the corrective surgery.

Part two deals with his femur.  Occasionally (approximately 1 out of 20 cases) there is also a deformity of the femur that must be corrected at the time of surgery by a proximal femoral osteotomy (PFO). This involves cutting and repositioning the upper portion of the femur bone. If this is indicated, a second incision is made along the outside of the hip and the femur is repositioned and fixed with a metal plate and screws.  All together, the surgery is estimated to take about four hours. 

Outlook, as previously stated, does look promising.  Although, that's what we thought after the first, and then second, surgery years ago.  The hospitalization time is two to four days and full recovery takes four to six months. Most likely, he will be given a wheelchair again and then after a few weeks he will graduate to crutches or a walker for what they call "touchdown weight bearing."  The majority of patients experience major relief of pain and become quite active after recovery from surgery. While the PAO is an extremely effective hip preservation procedure, it may not create a completely normal hip. Even if the PAO is effective in adolescence or early adulthood, some patients are likely to require a total hip replacement surgery later in life.  Noah will then need more physical therapy after he's healed to help with joint healing.

Still interested in what Noah has to look forward to?  Check out http://hipdysplasia.org