Arthroscopic Treatment for Shoulder Instability with Glenoid Bone Loss Using Distal Tibia Allograft Augmentation: Two Year Outcomes

Objectives: To analyse the clinico-radiologic outcomes of patients who underwent an all arthroscopic procedure to treat shoulder instability with glenoid bone loss using a distal tibial allograft; with a minimum 2 year follow-up.Methods: A retrospective chart review of prospectively collected data was completed for patients who underwent arthroscopic stabilization with Bankart repair and allograft bony augmentation of the glenoid; by the same surgeon. Western Ontario Shoulder Instability Index (WOSI), Disability of the Arm Shoulder and Hand (DASH), Veterans Rand - 12 and MARX questionnaires were completed pre and post-operatively. Radiological assessment was performed with radiographs and CT scans obtained pre-operatively and at approximately one year post surgery.Results: A total of 41 patients (29 males, 12 females) with a mean age of 26 ± 9 years were included. An excellent safety profile was observed, with no intraoperative complications, neurovascular injuries, adverse events, bleeding, or infections. At 2- year follow-up, there was statistically significant improvement of the WOSI score when compared preoperatively (preoperative=62.6 ± 17.06; at 2-year=22.96± 12.92; p<0.001). The mean pre-operative bone loss was 30.32% (SD ± 7.90). There were no cases of non- union or partial union. No resorption of the graft (grade 0) was seen in 42% patients, whereas 42% and 16% of patients had grade 1 and grade 2 resorption; respectively. There was 100% healing at the interface between allograft and native glenoid. The mean sagittal dimension of the remaining allograft post-operatively was 5.10 ± 2.27 mm in the patients with ≥50% resorption which indicates there was still bone graft present and there was no complete resorption. Mean post-operative external rotation for the population was also observed to near full.Conclusion: Arthroscopic stabilization with DTA augmentation has an excellent outcome at 2-year follow-up; long-term follow-up studies are necessary for better assessment of outcomes.