Outcome of surgical treatment of inter prosthetic fractures: A case series

摘要

Introduction. - Interprosthetic fractures occur between a total knee replacement and a femoral stem of either a hemiarthroplasty or total hip replacement. The number of interprosthetic fractures will increase as the number of joint replacements rises. There is currently a paucity of literature looking at the outcomes of interprosthetic fractures. Therefore, we performed a retrospective study to: (1) Determine fracture union in patients following surgical treatment of a femoral interprosthetic fracture, (2) measure outcomes included mortality and complications. Hypothesis. - Favouring bone fixation instead of prosthetic revision gives an acceptable rate of re-operation. Materials and Methods. - A retrospective case note review of all interprosthetic femoral fractures admitted to a tertiary trauma centre over a 7-year period. There were 24 patients (4 males and 20 females) with a mean age of 82.3 (65-98). The initial operative procedure was a total hip replacement (THR) and a total knee replacement (TKR) in 19 patients, one THR and revision TKR, four hip hemiarthroplasty and TKR. There were 23-cemented femoral stems, and 1 uncemented femoral stem. The median time to surgery was 84 hours. The median length of hospital stay was 16 days. Nineteen patients underwent open reduction internal fixation and 1 of these used a strut graft. Two patients underwent revision knee replacements and 3 underwent a revision hip replacement. All patients had at least 2 years clinical follow-up. Results. - One patient died within 30 days of fracture, leaving 23 patients to assess bone union. Another patient died within 1 year of fracture. Three out of 24 patients (12.5%) suffered a complication that required further surgery. The fracture united in 19/23 (82.6%) of patients and the two-year mortality rate was 5/24 (20.8%). Discussion. - Interprosthetic fractures are complex fractures occurring in elderly patients with multiple medical comorbidities. Whenever possible bone fixation instead of prosthetic revision give a low rate of complication and re-operation. The surgical treatments are complex, but with a well-performed surgical technique and an adequate rehabilitation program can result in satisfactory outcomes. Level of evidence. - IV, Retrospective Case series.