Paper 08: Arthroscopic Bankart Repair for Anterior Glenohumeral Instability in Adolescent Athletes: Risk Factors for Subsequent Revision Stabilization

Objectives: Adolescent athletes with a primary anterior glenohumeral dislocations have been shown to have a relatively high incidence of recurrent instability. Evolving evidence on this topic has led to increasing rates of arthroscopic stabilization over the last 2 decades. However, the timing and role of surgery following a single dislocation episode is one of the most controversial topics in orthopaedics. While arthroscopic stabilization is effective in allowing return to play, adolescents have higher rates of subsequent recurrent instability than any other age group. Identifying patients at highest risk of such events postoperatively may facilitate optimized surgical decision-making in this population. The purpose of this study was to identify prognostic factors that are associated with recurrent instability requiring reoperation following arthroscopic Bankart repair in adolescents, with particular attention to the number of dislocations sustained prior to the index procedure. Methods: All patients 12 to 21 years old who had undergone arthroscopic Bankart repair surgery for anterior glenohumeral instability at a pediatric tertiary care hospital between 2000 and 2020 were included. The analysis was conducted using a multivariate Cox proportional hazards model, with percentage of patients with recurrent instability requiring a re-operation evaluated in a time-to-event analysis as the outcome. The effects from the Cox model were expressed as the hazard ratio (HR). All tests were 2-sided, with an alpha level of .05. Results: A total of 488 adolescent patients (78% male; mean age: 16.9 +/- 1.98 years) met study criteria, with the most common primary sports consisting of football (n=141, 29%), hockey (n=47, 10%), basketball (n=40, 8%), baseball (n=33, 7%), and lacrosse (n=30, 6%). A total of 270 (55%) athletes participated in contact sports, while 95 (20%) were overhead athletes. Overall, 86 patients (17.6%) required revision stabilization surgery for recurrent instability, with a cumulative risk of 8.8% at 2 years, 16.5% at 5 years, and 20% at 15 years. The revision stabilization procedures occurred at a mean of 31.1 +/- 25.1 months from the index procedure and consisted of open Latarjet (n=42, 49%), revision arthroscopic stabilization (n=24, 28%), or open capsulorraphy (n=20, 23%). Risk factors for recurrent instability requiring revision stabilization included more than 1 dislocation episode prior to the index procedure (2 dislocations: HR=7.4 (2.5-21.6), p=0.0003; 3+ dislocations: HR=10.9 (3.9 to 30.5), p<0.0001), presence of a Hill-Sachs lesion (small Hill-Sachs: HR=2.5 (1.2-5.1), p=0.0114; medium-large Hill-Sachs: HR=4.2 (1.9-9.3), p=0.0004), younger age at the time of the index stabilization procedure (one year decrease in age: HR=1.2 (1.1-1.4), p=0.0015), and participation in contact sports (HR=1.8 (1.1-2.9), p=0.01). Adolescents who had sustained 1 dislocation prior to surgery had a cumulative incidence of revision surgery (3.2%) that was significantly lower than those who had sustained 2 dislocations (24.2%) or 3+ dislocations (33.5%). Conclusions: The number of dislocation episodes prior to index arthroscopic Bankart repair was the strongest risk factor for recurrent instability requiring revision surgery in adolescents with anterior glenohumeral instability, with two dislocation episodes conferring more than 7-fold increased risk compared to those who had just a single dislocation episode preoperatively. Other significant risk factors included the presence of a Hill-Sachs lesion, younger age, and participation in contact sports. These data support consideration for arthroscopic stabilization for adolescents following a single dislocation, especially in younger patients, contact athletes or when a Hill Sachs lesion is present.