Dual versus single implant fixation for geriatric distal femur fractures: protocol for a randomised, controlled pilot study at five US level 1 trauma centres.

INTRODUCTION

Geriatric distal femur fractures are associated with mortality rates exceeding 20%, comparable to hip fractures. Traditional single implant fixation often requires weight-bearing restrictions that delay recovery. This pilot study aims to assess the feasibility of conducting a multicentre randomised controlled trial comparing dual vs single implant fixation for geriatric distal femur fractures.

METHODS AND ANALYSIS: This multicentre, prospective, randomised controlled pilot trial will enrol 80 participants aged 60 years or older with displaced distal femur fractures at five US level 1 trauma centres. Patients will be randomly allocated 1:1 to receive either single implant (lateral plate or retrograde nail) or dual implant (nail-plate or dual plate) fixation. All patients will be permitted immediate weight-bearing. The primary outcome is feasibility assessed through enrolment rate (80 patients in 12 months), protocol adherence (≥90%) and follow-up retention (≥85% at 12 months). Secondary outcomes include post-surgical mobility (AM-PAC, TUG), patient-reported outcomes (PROMIS-PF, PROMIS-29), mortality (90-day and 1 year) and complication rates. Analyses will be on an intention-to-treat basis.

ETHICS AND DISSEMINATION: The protocol was approved by the University of Utah Institutional Review Board (IRB_00149119) and IRBs at all participating centres. Written informed consent will be obtained from participants or legally authorised representatives. Findings will be disseminated through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER: NCT05292313.