Orthopaedics & traumatology, surgery & research : OTSR | 2021
Does anterior arthroscopic acromioplasty modify critical shoulder angle?
Abstract
INTRODUCTION\nCritical shoulder angle (CSA) is measured on AP view in neutral rotation as the angle subtended by the tangent to the glenoid and the lateral edge of the acromion. CSA >35° is a risk factor for primary rotator cuff tear and iterative tear after cuff repair. The aim of the present study was to assess change in CSA following arthroscopic anterior acromioplasty.\n\n\nHYPOTHESIS\nCSA is decreased by arthroscopic anterior acromioplasty.\n\n\nMATERIAL AND METHOD\nA single-center retrospective descriptive observational study included patients undergoing arthroscopic acromioplasty between January 2016 and December 2017, for whom strictly AP pre- and post-operative radiographs were available. Patients with history of surgery, fracture or dislocation in the same shoulder were excluded.\n\n\nRESULTS\n102 patients were included; mean age, 50.5 years (range, 23-82 years). Mean preoperative CSA was 34.7±4.4° (range, 26-48°) and postoperative CSA 31.7±3.7° (range, 23-40°) (p < 0.001). In the pathological CSA group (>35°), the values were 38.9±2.8° (36-48°) and 34.4±3.2° (28-40°) (p < 0.001), with a 64.3% rate of correction after acromioplasty.\n\n\nDISCUSSION\nCSA decreased after arthroscopic acromioplasty. Even so, 36.7% of pathological CSAs (>35°) were not corrected, with risk of rotator cuff tear.\n\n\nCONCLUSION\nAnterior arthroscopic acromioplasty significantly reduced CSA overall, notably in case of high CSA.\n\n\nLEVEL OF EVIDENCE\nIV, retrospective study.