Glenoid reconstruction with screw-type implant versus iliac crest bone grafting for anterior shoulder instability: study protocol for a prospective, multicentre, non-inferiority, randomised controlled trial.

Abstract

Anterior shoulder instability is a common condition, frequently seen in young and active individuals. For patients with critical glenoid bone defects (≥15%), Bankart repair has limited effectiveness and bony augmentation surgery is often required. However, traditional bone grafts carry the risk of graft resorption, while 3D-printed personalised implants aimed at anatomical reconstruction face limitations in accessibility, cost and production time. In this multicentre, randomised controlled trial, anterior shoulder instability patients with critical glenoid bone loss will be screened across five centres. Individuals with multidirectional shoulder instability, concomitant ipsilateral shoulder injuries, concurrent diseases that may affect the joint or those ineligible for surgical intervention will be excluded.Randomisation will be performed in a 1:1 ratio, stratified by age, physical activity level and trial centre. Participants will receive either iliac crest bone grafting (ICBG) or glenoid reconstruction with screw-type implant. The primary analysis will be the difference of the Rowe score between ICBG and glenoid reconstruction patients at 1 year postoperatively. We set the non-inferiority margin at 6 points, corresponding to 60% of the MCID to ensure the clinical relevance of the non-inferiority test. Funded by the Medical Scientific Research Project of the First Affiliated Hospital of Chongqing Medical University (2025QDLXZX-07); Ethics Committee of the First Affiliated Hospital of Chongqing Medical University approved (ZZ2025-938-01). Final results will be updated on trial registries and submitted to a peer-reviewed journal and provide a novel treatment option for patients with anterior shoulder instability and offer a theoretical foundation and evidence base for the development of treatment strategies for similar cases in the future. ChiCtr2500115163.