Objective
In the setting of anterior shoulder instability, both boney and soft tissue structures are at risk of injury. Often, there is an injury to the anterior capsulolabral complex. This pathology is most often treated with a traditional arthroscopic Bankart repair. The open Bankart is regaining popularity as some surgeons report a lower re-dislocation rate as compared to its arthroscopic counterpart. Some believe that a better capsular shift is achieved with open surgery. We recently developed a technique for performing this capsular shift arthroscopically. The purpose of this study is to analyze and compare clinical outcomes of patients with traumatic anterior shoulder instability treated with two different arthroscopic techniques, arthroscopic capsular shift and arthroscopic Bankart repair (Figure 1). The primary objective of this study is to analyze and compare clinical outcomes, Western Ontario Shoulder Instability (WOSI) scores, complication, and re-dislocation rates. We hypothesize that patients treated with arthroscopic capsular shift will have similar clinical outcomes and a lower failure rate at one year compared with the other surgical cohort.
Methods
This study included patients who underwent arthroscopic soft-tissue stabilization surgery for shoulder instability between 2012-2021. Patients were included if they had an isolated primary soft-tissue repair performed arthroscopically with one of the above-mentioned surgical techniques. Patients were excluded if they had concomitant glenoid fractures, less than one year of clinical follow-up, posterior instability, multidirectional instability, and presence of HAGL lesions Demographic information, WOSI scores, pre-operative glenoid and humeral head dimensions, and new dislocation events were recorded.
Results
Sixty-three patients met the inclusion and exclusion criteria. There were 27 patients in the Bankart repair group and 36 in the capsular shift group. The two groups had similar demographics and baseline characteristics, except for the length of clinical follow-up (which is due to the capsular shift technique being developed more recently) (p<0.001) (Table 1). Both groups had similar pre-operative glenoid AP and Hill-Sachs depth measurements (p=0.358 and 0.329, respectively) (Table 1). Patient-reported outcomes were similar at baseline (p=0.602) and post-operatively (p=0.621). Both groups showed improvements in WOSI post-operatively (p<0.001), however more patients met MCID in the capsular shift group as compared to the Bankart repair group (93% vs 75%, respectively). In terms of clinical outcomes, patients who received a capsular shift had a lower rate of re-dislocation as compared to the Bankart group (6% vs 22%).
Conclusions
The arthroscopic capsular shift technique results in better post-operative clinical outcomes as compared to arthroscopic Bankart repair with a lower recurrence rate, lower rate of post-operative apprehension, and an increased proportion of patients who meet MCID for WOSI. This technique could be a better alternative for Bankart repair in patients with soft-tissue pathologies following anterior shoulder dislocations, however longer-term studies are necessary to determine the longevity of these outcomes