Skeletally mature acetabular dysplasia: Epidemiology, natural history, clinical presentation, imaging studies, non-operative treatment, operative treatment

Skeletally mature acetabular dysplasia (SMAD) is a recognized cause of hip pain in active young adults. The majority of hip dysplasia is treated in childhood by improving the physiologic and anatomic environment of the hip allowing it to develop into a morphologically sound structure. The abnormal morphology of the mature dysplastic hip can be subtle both clinically and radiographically which can often lead to a delay in diagnosis. The goal of treatment with SMAD is first and foremost to recognize the specific pathology causing the common complaints of hip pain. Hip pain, limp, and mechanical symptoms that can present with SMAD may be the same presenting complaints in patients with either femoroacetabular impingement (FAI) or mild osteoarthritis (OA). Plain radiographs and MRI provide the diagnosis, which in turn allows the treating physician to choose the appropriate treatment course. Treatment of SMAD generally falls into one of two categories. For patients who present without radiographic signs of OA, the goal is to preserve the native cartilage of the hip by creating a more mechanically sound hip. The periacetabular osteotomy (PAO) reorients the acetabulum, providing stability to the hip and decreasing cartilage stress. Patients who present with moderate to severe OA generally do not obtain good results with hip preservation procedures and, therefore, may require total hip arthroplasty to address their hip pain. Although results are excellent with total joint replacement, the mainstay of treatment for SMAD should be recognition via clinical and radiographic examination followed by prompt treatment, if indicated, to help preserve the native hip joint.