Reasons for Revision: Primary Total Hip Arthroplasty Mechanisms of Failure

Background: This study aimed to examine the major reasons for total hip arthroplasty (THA) failure and temporal patterns in THA revisions. Methods: A retrospective chart review was conducted on 535 revisions performed on 444 THAs from January 2010 to May 2019 at our institution. Results: The average time to revision THA was 8.51 +/- 8.38 years, with 136 cases (30.9%) occurring within 2 years after primary THA. The major mechanisms of failure that resulted in revision surgery were mechanical failure (162, 36.5%), metallosis (95, 21.4%), dislocation or instability (65, 14.6%), periprosthetic fracture (46, 10.4%), infection (44, 9.9%), hematoma or poor wound healing (15, 3.4%), and pain or other (17, 3.8%). Conclusion: Based on our institutional experience over the past decade, mechanical failure without dislocation, metallosis, dislocation, periprosthetic fracture, and infection are typical reasons patients present for primary THA revision. Revisions within 2 years after primary THA are more likely to be the result of infection and periprosthetic fracture. Mechanical failure is the most common reason for revision THA overall, and mechanical failure and metallosis are more likely to be the reason revision is necessary 2 or more years after primary THA.