Fractures after hemialloplastic hip replacement.

Forty-four patients sustaining ipsilateral femoral shaft fractures after hemialloplastic hip replacements are evaluated according to risk factors for the fractures, treatment and social costs. The fracture incidence was 0.10, and almost half of the fractures occurred within 1 year after the initial alloplastic operation. Possible factors increasing the risk of secondary fracture included loosening of the prosthesis (eight cases), osteoporosis (14 cases), varus angulation of the femoral stem (28 cases), calcar resorption (nine cases), major capsular calcifications (four cases), and cortical defects at the tip of the stem (three cases). The importance of correct insertion of the prostheses is emphasized. The degree of mobilization after fracture healing was overall reduced and most pronounced with increasing age and not correlated to treatment. The earliest mobilization was obtained in patients treated with long-stem prostheses supplemented with internal fixation, and this method of treatment is advocated.