Increased risk for postoperative periprosthetic fracture in hip fracture patients with the Exeter stem than the anatomic SP2 Lubinus stem.

ABSTRACT

BACKGROUND: The purpose of this study was to compare the cumulative incidence of postoperative periprosthetic fracture (PPF) in a cohort of femoral neck fracture (FNF) patients treated with two commonly used cemented stems either a collarless, polished, tapered Exeter stem or the anatomic Lubinus SP2 stem. METHODS: In this retrospective multicenter cohort study of a consecutive series of patients, we included 2528 patients of age 60 years and above with an FNF who were treated with either hemiarthroplasty or total hip arthroplasty using either a polished tapered Exeter stem or an anatomic Lubinus SP2 stem. The incidence of PPF was assessed at a minimum of 2 years postoperatively. RESULTS: The incidence of PPF was assessed at a median follow-up of 47 months postoperatively. Thirty nine patients (1.5%) sustained a PPF at a median of 27 months (range 0-96 months) postoperatively. Two of the operatively treated fractures were Vancouver A (5%), 7 were Vancouver B1 (18%), 10 were Vancouver B2 (26%), 7 were Vancouver B3 (18%), and 13 were Vancouver C (32%). The cumulative incidence of PPF was 2.3% in the Exeter group compared with 0.7% in the SP2 group (p < 0.001). The HR was 5.4 (95% CI 2.4-12.5, p < 0.001), using the SP2 group as the denominator. CONCLUSIONS: The Exeter stem was associated with a higher risk for PPF than the Lubinus SP2 stem. We suggest that the tapered Exeter stem should be used with caution in the treatment of FNF. TRIAL REGISTRATION The study was registered at clinicaltrials.gov (identifier NCT03326271).