Abstract
Developmental dysplasia of the hip (DDH) is relatively a common condition that can lead to early arthritis of the hip. Although total hip arthroplasty is the surgical treatment of choice for these patients with end stage arthritis, some patients afflicted with DDH may present early. Acetabular osteotomy, in particular Bernese or periacetabular osteotomy (PAO as described by Professor Ganz and Jeff Mast back in 1980s) may be an option with patients with symptomatic DDH who have joint space available. PAO has many advantages. First, it is performed through a single incision (modified Smith Peterson approach) without breaching the abductor mechanism. The periacetabular fragment has, hence, excellent blood supply and avascular necrosis of the acetabular portion is not an issue. In addition, the osteotomy is so versatile allowing for great mobility of the fragment to obtain coverage even in the worst of circumstances. The osteotomy does not affect the posterior column and hence allows for earlier weight bearing. Most joint preservation surgeons in North America and Europe prefer PAO to other types of osteotomy.
The indications for PAO are a patient with symptomatic DDH who has good joint space and a congruent joint. The congruency of the joint is usually determined by the abduction views (obtained at 30 degrees abduction and neutral rotation). Although the joint space may be measured on plain radiographs, in recent years some centers have been utilising cross sectional imaging, such as dGEMERIC for evaluation of the articular cartilage, which has been shown to be a good predictor of outcome for PAO.
