Comparative surgical outcomes in chronic acromioclavicular joint instability: A 165-patient series using local, remote, and synthetic graft reconstructions

Background Three graft types, including local autograft, remote autograft/allograft, and synthetic graft are used for chronic acromioclavicular joint instability reconstructive surgery, and this study aims to compare their surgical outcomes. Methods This retrospective multicenter study included 165 patients treated surgically for chronic acromioclavicular joint instability. Patients underwent reconstruction using local autograft (n=107), remote autograft/allograft (n=39), or synthetic grafts (n=19). The primary endpoint was surgical failure (recurrence or loss of stabilization). Secondary outcomes included pain (VAS), functional scores (Constant-Murley, SSV), range of motion, residual instability, radiographic outcomes, and complications. Results At a median follow-up of 44.9 months (IQR: 24.0-89.6), the overall failure rate was 15.7%, with no significant differences between local autograft (15.8%), remote autograft/allograft (12.8%), and synthetic grafts (21.1%) ( P =0.72). Surgical revision was required in 3.3% of patients overall, and was more frequent in the synthetic graft group (15.8%, P =0.0119). All techniques resulted in significant improvements in pain, function, and range of motion. Mean VAS decreased from 4.9 to 1.2, and functional scores improved across groups without differences between. Radiographic correction (reduction of separation) was greatest with local autografts, although residual anterior-posterior instability was also more frequent in this group. Complications occurred in 20.0% of patients, significantly higher with synthetic grafts (42.1%, P =0.0366). Capsulitis was the most common late complication (7.3% overall; 26.3% in the synthetic graft group). Conclusions Surgical reconstruction for chronic acromioclavicular joint instability provides substantial and sustained improvements, regardless of graft type. Although failure rates were comparable, synthetic grafts were associated with higher complication and revision rates.