PATHOGENESIS OF BONE LOSS AFTER TOTAL HIP-ARTHROPLASTY

Bone loss with or without evidence of aseptic loosening is a long-term complication after total hip arthroplasty (THA). It occurs with all m aterials and in all prosthetic systems in use or that have been used t o date. Boneless after THA can be a serious problem in revision surger y because bone deficiencies may limit reconstructive options, increase the difficulty of surgery, and necessitate autogenous or allogenic bo ne grafting. There are three factors adversely affecting maintenance o f bone mass after THA: (1) bone loss secondary to particulate debris; (2) adaptive bone remodeling and stress shielding secondary to size, m aterial properties, and surface characteristics of contemporary prosth eses; and (3) bone loss as a consequence of natural aging. This chapte r reviews the mechanisms of the primary causes of bone loss after THA.