Mechanical safety of calcar-guided short stems in elderly femoral neck fractures: A 433-patient cohort study.

BACKGROUND

Achieving reliable primary fixation in elderly patients with femoral neck fractures remains challenging, particularly when using uncemented stems. Calcar-guided metaphyseal-diaphyseal short stems have been proposed as an alternative; however, evidence regarding their mechanical safety in fracture settings remains limited. This study aimed to evaluate the incidence of early periprosthetic femoral fracture following implantation of a calcar-guided short stem and to identify factors associated with fracture and stem subsidence.

HYPOTHESIS: Calcar-guided short stems provide satisfactory mechanical safety without an excessive rate of early periprosthetic fracture in elderly fracture patients.

MATERIALS AND

METHODS

We conducted a retrospective single-center cohort study including consecutive patients aged ≥70 years treated between 2017 and 2025 with total hip arthroplasty or hemiarthroplasty using an Optimys® short stem through a minimally invasive anterior approach. The primary endpoint was intraoperative or early postoperative periprosthetic femoral fracture requiring revision within 3 months. Secondary outcomes included clinically relevant stem subsidence (>2 mm). Given the low number of events, univariate and multivariable analyses were performed using Firth penalized logistic regression.

RESULTS

A total of 433 patients were included (mean age 84.6 ± 7.7 years). Overall, 21 femoral mechanical complications (4.9%) were observed, including 3 intraoperative calcar fractures treated with cerclage fixation and 18 early postoperative periprosthetic femoral fractures requiring revision surgery. Stem subsidence greater than 2 mm was observed in 24 patients (5.8%). No independent predictors of fracture were identified. Medial cortical support was the only independent protective factor against stem subsidence (OR = 0.08; 95% CI, 0.03-0.22; p < 0.001).

DISCUSSION: Metaphyseal-diaphyseal short stems appear to be a reasonable option for the treatment of femoral neck fractures in elderly patients. Primary stability appeared to depend mainly on achieving adequate medial cortical support. Longer follow-up is required to assess the long-term performance of these implants.

LEVEL OF EVIDENCE: IV; retrospective cohort study.