Background: Surgical treatment options for femoral neck fracture include arthroplasty and internal fixation (IF). An IF is associated with faster operation time, less blood loss, and fewer hospitalization days than arthroplasty. However, reoperation rates are significantly higher than treatment with total hip arthroplasty (fracture-THA). Most reoperations following IF include implant removal surgeries and conversions to THA (salvage-THA).

Methods: We assessed survivorship of 3,823 fracture-THA, 298 salvage-THA, and 73,141 THA performed for osteoarthritis based on the Finnish Arthroplasty Register using a Kaplan-Meier estimator. In addition, we conducted Cox regression analyses to assess risk factors for a revision operation after fracture-THA.

Results: Inferior Kaplan-Meier 7-year survivorship was observed in the fracture-THA (91.5%, 95% confidence interval (CI) [90.4 to 92.7]) and salvage THA (89.4%, 95% CI [84.8 to 94.1]) groups compared to the osteoarthritis-THA group (95.4%, 95% CI [95.2 to 95.5]). Survivorship between the fracture-THA group and the salvage-THA group was comparable. In the multivariate Cox regression analyses, for risk factors for revision due to infection, dislocation, or periprosthetic fracture, no statistically significant factors were identified.

Conclusion: We conclude that the 7-year survivorship of fracture-THA and salvage-THA is similar, but inferior than that of OA-THA.