**1. Introduction**

Osteonecrosis, also called avascular necrosis or aseptic necrosis, is the name given to a set of diseases that affect mainly young adults and that often evolve to deformities and osteoarthritis, generating serious functional incapacity. The most affected site in the human skeleton is the head of the femur, but it can occur in many other places.

Despite advances in the understanding of this condition, the pathogenesis, risk factors, and diagnosis are not yet fully understood. In addition, the available treatments are still controversial and may range from physiotherapy and medications to surgical procedures such as decompression and arthroplasties [1].

Some authors report that osteonecrosis is responsible for at least 10% of the hip arthroplasties practiced in the United States [2].
