Osteonecrosis: An OverviewSteinberg, David R. MD; Steinberg, Marvin E. MDTechniques in Orthopaedics: March 2008 - Volume 23 - Issue 1 - p 2-10 doi: 10.1097/BTO.0b013e3181692921 Articles Abstract Author Information Summary: This section is designed to give the reader a concise overview of a complicated subject to serve as a background to the main theme of this issue: how to treat nontraumatic osteonecrosis (ON) of the adult hip. It reviews the etiology and pathogenesis of ON, the clinical picture, and the importance of imaging techniques. Three of the most commonly used systems for classification and staging are described. The role of pharmacologic agents is discussed. Surgical procedures are generally divided into 2 categories: those instituted during the earlier stages, when the goal is to retard or halt progression of ON in order to preserve the femoral head; and those which are indicated after femoral head collapse and acetabular damage has taken place, and which include various arthroplasties and reconstructive procedures. From the Department of Orthopedic Surgery, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania. Reprints: Marvin E. Steinberg, MD, Professor Emeritus of Orthopaedic Surgery, University of Pennsylvania School of Medicine, Department of Orthopaedic Surgery, 3400 Spruce Street, Orthopedic Surgery/2 Silverstein Pavilion, Philadelphia, Pennsylvania 19104. E-mail: firstname.lastname@example.org. © 2008 Lippincott Williams & Wilkins, Inc.