Conversion Hip Arthroplasty Using Standard and Long Stems after Failed Internal Fixation of Intertrochanteric Fractures

Abstract Background: Failed internal fixation of intertrochanteric fractures is often treated by conversion hip arthroplasty (CHA). This study aimed to evaluate the results and complications of using long and standard femoral stems in this operation.Methods: This retrospective, multi-center study enrolled 31 total hip arthroplasty (THA) and 23 hemiarthroplasty (HA) cases (30 women, 24 men; mean age 76 years) after FIF-ITF between 2012 and 2019, divided into 2 groups: standard stem group (n = 20) and long stem group (n = 34). The initial internal fixation includes 38 cases of proximal femoral nail anti-rotation (PFNA), 8 cases of the dynamic hip screw (DHS), and 8 cases of locking proximal femoral plate (LPFP). The indications for CHA included 38 cases of failure of fixation, 7 cases of nonunion, and 9 cases of avascular necrosis or posttraumatic osteoarthritis. Perioperative data and complications related to fracture and operation were collected, and preoperative and postoperative clinical and radiological data were analyzed.Results: At an average of 5.6 years with a minimum of 2 years follow-up. A significant overall surgeon-related complication rate was detected (27.8% [15/54]), five cases had an intraoperative femur fracture, one case had a late periprosthetic femoral fracture, one case had a stem penetration, one case had a cement leakage, and two patients had an early postoperative dislocation, one infection and three cases of stem loosening or subsidence. Long stems had an increased risk of complication (13/34) compared to standard stems (2/20) (P= 0.031). The operation time and blood loss in the long stem group were higher than those in the standard stem group (P= 0.002;0.017). Harris Hip Score (HHS) and SF-36 significantly improved in both groups from preoperative to the final follow-up, and did not present significant differences at the final follow-up (P>0.05). Conclusion: A high complication rate was detected in CHA following failed internal fixation of intertrochanteric fractures, and long stem arthroplasty should be approached with caution to the risks of complications, especially intraoperative femur fractures.Level of evidence: III controlled cohort study