title: Fractures of the greater trochanter induced by osteolysis with the anatomic medullary locking prosthesis.
abstract: Pathologic fractures of the greater trochanter associated with trochanteric osteolysis are a late complication of total hip arthroplasty that have been described only in case reports. In this study of 208 consecutive total hip arthroplasties with mean 12.2-year radiographic follow-up, we reviewed the incidence, presentation, treatment, and outcome of such fractures. A radiographic review revealed 9 hips (4.3%) with trochanteric fractures resulting from osteolysis, occurring at a mean follow-up of 129 months. Five were diagnosed at the time of their radiographic appearance. Four were treated without operative fixation, using crutches and limited weight bearing for 4 to 6 weeks. Seven fractures healed in situ without major displacement. One resulted in a nonunion of the tip of the greater trochanter, and the radiographic outcome of a recent fracture was unknown. We found that the risk of sustaining a fracture was independent of the size of the osteolytic lesion; however, the risk increased significantly when the lysis eroded the cortical bone of the greater trochanter. In our experience with the extensively porous-coated AML stem (DePuy, a Johnson & Johnson Company, Warsaw, IN), conservative treatment leads to reasonable radiographic and clinical results in cases with limited initial fracture displacement.
authors.affiliation: Fakultaet fuer Klinische Medizin der Universitaet Heidelberg, Klinikum Mannheim gGmbH, Orthopaedische Universitaetsklinik, Mannheim, Germany.
authors.forename: Alexandra M
authors.initials: AM
authors.lastname: Claus
authors.forename: Robert H
authors.initials: RH
authors.lastname: Hopper
authors.forename: Charles A
authors.initials: CA
authors.lastname: Engh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D005260:Female; D005264:Femoral Fractures / Q000000981:diagnostic imaging / Q000209:etiology*; D015775:Fractures, Stress / Q000000981:diagnostic imaging / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000150:complications* / Q000209:etiology; D011859:Radiography; D012189:Retrospective Studies