Mid term Functional Outcomes of Open Latarjet Procedure with Congruent Arc Modification in Recurrent Anterior Shoulder Instability: A Retrospective Cohort Study

Background: Recurrent anterior shoulder instability associated with significant glenoid bone loss poses a high risk of failure with isolated soft tissue repair. The open Latarjet procedure with congruent arc modification has been proposed to enhance stability and graft coverage, but clinical evidence remains limited. Methods: A retrospective cohort study was conducted on patients undergoing open Latarjet with congruent arc modification between January 2015 and December 2020. Inclusion criteria were ≥3 anterior dislocations, ≥15% glenoid bone loss, and ≥24 months of follow-up. Functional outcomes (Western Ontario Shoulder Instability Index [WOSI], Rowe score), range of motion, complications, and graft union (CT) were assessed. Kaplan–Meier survival analysis estimated recurrence-free survival. Results: Eighty patients (62 males, 18 females; mean age 28.5 ± 6.4 years) were included with a mean follow-up of 4.5 ± 1.2 years. WOSI scores improved from 46.7 ± 12.3 to 79.4 ± 15.8 (p < 0.001), and Rowe scores from 32.5 ± 9.6 to 85.6 ± 10.7 (p < 0.001), both exceeding MCID thresholds. Forward flexion (+15°) and abduction (+20°) improved significantly, while external rotation showed a mild, non-significant reduction (–10°, p = 0.079). Complications occurred in 10 patients (12.5%), including graft nonunion (5%), transient axillary nerve symptoms (3.8%), recurrence (2.5%), and graft malposition (1.3%). Graft union was confirmed in 95% of patients, and recurrence-free survival was 97.5% at 5 years. Conclusion: The open Latarjet procedure with congruent arc modification provides excellent mid-term functional outcomes, durable stability, and low recurrence in patients with recurrent anterior shoulder instability and glenoid bone loss.