Complication Rates of Hemiarthroplasty Conversion to Total Hip Arthroplasty Versus Primary Total Hip Arthroplasty

Background One of the most common surgical options for treatment of a femoral neck fracture is hemiarthroplasty (HA). However, progression of arthritis or pain can necessitate conversion to total hip arthroplasty (THA). While conversion to a THA is a viable option, it does carry multiple risks. The purpose of this study was to identify whether performing conversion from HA to THA carries an increased risk of post-operative joint complications when compared to elective THA. Methods An administrative claims database was queried to identify patients who underwent conversion from a HA to a THA. Incidences of prosthetic dislocation, prosthetic joint infection (PJI), periprosthetic fracture, aseptic loosening, and revision were collected and compared to elective primary THA with multivariable logistic regression. Results Patients undergoing conversion THA had significantly higher risks of all joint complications examined at both 1 and 2 years after surgery. These included prosthetic dislocation (1-year: OR 2.95; 2 years: OR 3.77), PJI (1-year: OR 1.38; 2 years: OR 2.13), periprosthetic fracture (1-year: OR 2.95; 2 years: OR 3.75), aseptic loosening (1-year: OR 6.86; 2 years: OR 7.70), and revision (1-year: OR 3.65; 2 years: OR 6.73). Conclusion Performing conversion arthroplasty from HA to THA is associated with an increased risk of multiple joint complications in both the short and mid-term follow-up period. Surgeons should consider these complications when indicating HA for femoral neck fractures and elective conversion arthroplasty.