Osteolysis of the femur: principles of management.

Femoral osteolysis is and will remain an important cause of THA failures. The presentation is initially radiographic and patients may or may not become symptomatic. If so, pain is the most common symptom. Infection is the most common differential diagnosis and must be excluded. Osteolysis is usually progressive and may eventually lead to loss of implant fixation, implant fracture, or periprosthetic fracture. Multiple factors influence the decision to revise a femoral component, including the degree and type of bone loss, the rate at which it is progressing, the potential for fracture, the degree of symptoms, especially pain, and the activity level and general health of the patient. There are many options for revising failed femoral stems, each with varying degrees of success. The choice of technique and prosthesis used in the revision can be guided by a simple bone defect classification presented in this chapter. Revision of femoral components in these patients can be fraught with complications and poor results; hence, the importance of preoperative planning cannot be overemphasized.