Rotator Cuff Tears are Significantly More Frequent in Recurrent Shoulder Instability Patients With Initial Dislocation at Age 40 or Older

Abstract

PurposeThe purpose of this study was to investigate and compare the pathologies and clinical outcomes of patients with traumatic anterior shoulder instability who underwent arthroscopic stabilization at 40 years or older between shoulders with initial dislocation before and after 40 years old. MethodsShoulders that underwent arthroscopic stabilization for recurrent traumatic anterior shoulder instability at 40 years or older with a minimum of two-year follow-up were included. The subjects were divided into two groups according to the age at initial dislocation after a propensity score matching to reduce potential bias: Group 1, < 40 years old; Group 2, ≥40 years. Radiographic findings, pathologies, clinical outcomes, and complications were compared between the groups ResultsGroup 1 included 56 shoulders in 56 patients (26 males and 30 females) with a mean age of 51 (range, 40-77) years. Group 2 included 28 shoulders in 28 patients (13 males and 15 females) with a mean age of 51 (range, 40-77) years. The glenoid bone loss was greater in Group 1 than in Group 2 (p=.004). Rotator cuff tears were more frequently observed in Group 2 than in Group 1 (P<.001). Both groups demonstrated significant improvement in the West Ontario Shoulder Instability Index (P<.001 for each) and flexion (P<.001 for each). Recurrence was seen in 4% in Group 1 and 7% in Group 2. ConclusionsThe incidence of concomitant rotator cuff tears was significantly higher in shoulders with initial dislocation after 40 years than those before. Arthroscopic stabilization yielded a low recurrence rate and favorable outcomes with good sports return in patients 40 years or older.