Relationship Between Age at Initial Shoulder Instability and Overall Outcomes After Arthroscopic Bankart Repair: Mean 6-Year Follow-up

BACKGROUND: Age at surgery plays a crucial role in the frequency of recurrent shoulder instability. However, there are few studies that evaluate the relationship between age at initial shoulder instability and overall outcomes after stabilization surgery. PURPOSE: To compare clinical outcomes and structural changes after arthroscopic Bankart repair in patients who experienced initial shoulder instability during adolescence versus those with later onset instability. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This study included patients who underwent arthroscopic Bankart repair at a single institution between 2007 and 2017. Comparisons were made between patients who experienced initial shoulder instability during adolescence (age 13-19 years; group A) and those with later onset instability (age 20-35 years; group B). Clinical outcomes (recurrence rate, postoperative pain, functional scores, active range of motion, and return to sports) and structural changes demonstrated by magnetic resonance imaging (MRI) were evaluated at minimum 2-year follow-up. In addition, functional outcomes within each group were compared between the patients with and without postoperative recurrence. RESULTS: A total of 58 patients were included (24 patients in group A and 34 patients in group B). The mean follow-up was 72.1 months. Group A demonstrated a significantly higher recurrence rate than group B (41.7% vs 11.8%, respectively; P = .009; risk ratio, 5.36 [95% CI, 1.43-20.09]) as well as significantly lower Rowe (76.9 ± 20.1 vs 88.7 ± 13.2, respectively; P = .01) and Constant-Murley scores (92.2 ± 7.6 vs 96.3 ± 4.2, respectively; P = .01). Postoperative MRI revealed no significant structural differences between the groups regarding the glenoid labrum, glenohumeral cartilage, or osseous reaction around the implanted anchors. In group A, patients with recurrence had less satisfaction regarding postoperative sports level than those without recurrence, whereas in group B, patients with recurrence had more postoperative pain and functional impairment compared with those without recurrence. CONCLUSION: Initial shoulder instability during adolescence was associated with a higher recurrence rate and lower functional scores after arthroscopic Bankart repair compared with later onset instability, although no significant structural differences were found between the groups on MRI at a mean 6-year follow-up.