Introduction: The purpose of this study was to compare the outcome after arthroscopic antero-inferior shoulder stabilization with and without using a 5:30 o'clock portal.
Materials and methods: Sixty-two patients [age (mean ± SD), 28.05 ± 8.25 years] with a mean follow-up of 15.23 ± 5.02 months were included in this study. Thirty-one patients underwent arthroscopic antero-inferior shoulder stabilization using the 5:30 o'clock portal in center A (group I) and were compared to 31 matched patients managed with the 3 o'clock portal in center B (group II). Physical examination, standard shoulder scores, ultrasound assessment and subscapularis strength measurement were used to evaluate postoperative shoulder function.
Results: Good to excellent results were seen in both groups. No significant differences were seen when comparing ASES, Constant and Rowe Score of both groups. Patients of group II achieved a significant higher score in the SST than patients of group I. (p < 0.05) Patients of group I had a significantly lesser loss of passive external rotation in 0° and 90° of abduction. (p = 0.04; p = 0.056) Ultrasound evaluation and strength measurement showed no significant differences in subscapularis muscle integrity or function neither between the involved and uninvolved shoulder nor between both groups.
Conclusion: Arthroscopic anterior-inferior shoulder stabilization results in excellent clinical results. When considering portal placement, the deep trans-subscapularis portal allows a more precise suture anchor placement at the inferior glenoid rim and capsular shift with a significant improved external rotation but does not negatively affect the subscapularis function in terms of internal rotation strength or structural integrity.
Level of evidence: III.
Keywords: Arthroscopy; Bankart repair; Range of motion; Shoulder stabilization; Strength; Subscapularis.