Background: Accompanying injuries are frequently seen in middle aged patients with recurrent instability. The aim of this study was to elucidate the associated injuries, report patient outcomes of the following arthroscopic instability surgery regarding 40-60 years old patients with recurrent shoulder instability. Methods: Patients that underwent arthroscopic instability surgery due to recurrent shoulder instability between February 2008 and November 2015, and which were 40-60 years old were included and evaluated retrospectively. Minimum follow-up duration was 24 months. Anterior-inferior labral injuries and accompanying pathologies such as rotator cuff tears and SLAP lesions were documented. Postoperative patient-reported outcome evaluation was made using Oxford Shoulder Instability Score. Results: Among 355 patients that underwent arthroscopic instability surgery, 88 patients which had pathology of recurrent instability were in the range of 40-60 years old. Patients who had previous shoulder surgery or fracture (n = 8) epileptic seizure history (n = 3), neurologic deficit (n = 2) were excluded from the study. 75 patients were included with a mean follow-up 69 +/- 23 months (32-125). The percentage of middle-aged and elderly (40-60 years old) was 24.8% among recurrent shoulder instability patients. 44% had isolated Bankart lesion whereas 56% revealed multiple pathologies. Bankart + SLAP lesions were found in 32%, whereas Bankart + Rotator Cuff tears in 26.7% (13 isolated supraspinatus, 4 supraspinatus + subscapularis, 1 isolated subscapularis full-thickness and 2 partial thickness supraspinatus tears). The mean Oxford Shoulder Instability Score was 38.4 +/- 5.2 (26-48). The scores of patients which were treated with labrum and rotator cuff repair (median 42, range 30-48) were significantly better than the patients who were treated with isolated labrum repair (median 39, range 20-46) (p = 0.015). There was no difference regarding patients with or without SLAP repair (median 39 vs 39 and range 30-48 vs 20-48, respectively) (p = 0.702). Conclusions: Arthroscopic repair of capsulolabral lesions is a safe and successful technique in 40-60 years old patients. Furthermore, the presence of repaired rotator cuff tears led to even superior results. Accompanying SLAP lesions did not affect the results. Study design: Retrospective Case Series. Level of evidence: 4, Retrospective Case Series. (c) 2020 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.