Peri-implant femoral fractures in hip fracture patients treated with osteosynthesis: a retrospective cohort study of 1965 patients.

background and purposeThere are few studies on incidence rates, treatment and outcomes for peri-implant femoral fractures (PIFF) in the proximity of osteosynthesis. The purpose of this study was to investigate the incidence of PIFF following osteosynthesis of proximal femoral fractures. PATIENTS AND

methodsThis retrospective cohort study comprised a consecutive series of hip fracture patients aged 50 years or older and operated with osteosynthesis between 2003 and 2015. Patients were followed-up until 2018, removal of implants or death, for a mean of 4 years (range 0-15). Data on age, sex, housing, hip complications, and reoperations were recorded. The risk of PIFFs was assessed using Cox proportional hazards regression analysis. In patients with two fractures during the study period, only the first fracture was included.

resultsA total of 1965 osteosynthesis procedures were performed, of which 382 were cephalomedullary nails (CMN), 933 sliding hip devices (SHD) and 650 pins. Mean age was 80 years (range 50-104), 65% of patients were women. A total of 41 PIFFs occurred during the study period. The cumulative incidence of peri-implant fractures was 0.8% for CMN, 2.7% (HR 2.995% CI, 0.87-9.6, p = 0.08) for SHD and 2.0% (HR 2.3 95% CI, 0.6-8.1, p = 0.2) for pins. PIFFs occurred after a mean of 27 months (range 0-143). The 1-year mortality was 34% following PIFF. The majority was treated surgically (66%, 27/41) and the reoperation rate was 15% (4/27).

conclusionIn this retrospective cohort study, in contrast to previous reports, we found a tendency to a higher cumulative incidence of PIFFs for SHD compared to modern CMN. Our results show cumulative incidences of PIFFs comparable to those described for periprosthetic femur fractures after hip arthroplasty for femoral neck fracture.