Clinical and radiographic outcomes of primary vs. revision arthroscopic anatomic glenoid reconstruction with distal tibial allograft for anterior shoulder instability with bone loss.

Background: The purpose of this study was to assess the clinical and radiographic outcomes of arthroscopic anatomic glenoid reconstruction (AAGR) used for primary vs. revision surgery for addressing anterior shoulder instability with bone loss.

Methods: We performed a retrospective review on consecutive patients who underwent AAGR from 2012 to 2020. Patients who received AAGR for anterior shoulder instability with bone loss and had a minimum follow-up of 2 years were included. Exclusion criteria included patients with incomplete primary patient-reported outcome scores (PROs), multidirectional instability, glenoid fracture, nonrigid fixation and concomitant humeral avulsion of the glenohumeral ligament, or rotator cuff repair. Our primary outcome was measured using the Western Ontario Shoulder Instability Index (WOSI) scores. Secondary outcomes included postoperative Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH) scores, complications, recurrence of instability and computed tomographic (CT) evaluation of graft position, resorption, and healing.

Results: There were 73 patients (52 primary and 21 revision) finally included. Both groups had comparable demographics and preoperative WOSI and DASH scores. The primary group had significantly better postoperative WOSI and DASH scores at final follow-up when compared to the revision group (WOSI: 21.0 vs. 33.8, P = .019; DASH: 7.3 vs. 17.2, P = .001). The primary group also showed significantly better WOSI scores than the revision group at the 6-month, 1-year, and 2-year time points (P = .029, .022, and .003, respectively). The overall complication rate was 9.6% (5 of 52) in the primary group and 23.8% (5 of 21) in the revision group. Both groups showed good graft healing and placement in the anterior-to-posterior and mediolateral orientation and had a similar rate of graft resorption and remodeling. There was no difference between the groups in the remainder of the CT measurements.

Conclusion: Functional outcome scores and stiffness were significantly worse in patients undergoing an AAGR procedure after a failed instability surgery when compared with patients undergoing primary AAGR. There were no differences in postoperative recurrence of instability or radiographic outcomes. As a result, AAGR should be considered as a primary treatment option within current treatment algorithms for shoulder instability.