Shoulder impingement: various risk factors for supraspinatus tendon tear: A case group study

A total of 680 cases of monolateral shoulder pain and functional impairment were included, and Chi-Squared tests was incorporated to test for possible associations. No relation between impingement syndrome and potential risk factors was found, such as presence of down slopping (P = .083), presence of ossification acromiale (P = .102), presence of calcific tendinitis (P = .144), types of acromion (I [P = .600], II [P = .536], III [P = .633] and IV [P = .832]) and grade of acromioclavicular degenerative changes (mild [P = .077], moderate [P = .111], and severe [P = .700]). However, a significant relationship was uncovered between impingement syndrome and risk factors such as gender (X(2) = 7.004, df = 1, P = .08) (where females were more prone), history of shoulder dislocation (X(2) = 19.440, df = 1, P = .001), presence of supraspinatus tendon tear or tendinopathy (X(2) = 69.344, df = 1, P = .001) and supraspinatus complete tear (X(2) = 13.593, df = 1, P = .001). A significant relationship was found between the type of supraspinatus pathology and factors such as gender (female more prone) (X(2) = 34.719, df = 3, P = .01), presence of down slopping (X(2) = 57.765, df = 3, P = .01), history of shoulder dislocation (X(2) = 148.880, df = 3, P = .001), type III of the acromion (X(2) = 12.979, df = 3, P = .005), presence of acromioclavicular generative changes mild (X(2) = 76.408, df = 3, P = .001) and moderate (X(2) = 29.697, df = 3, P = .001), and acromiohumeral distance of ≤3 mm (X(2) = 18.915, df = 3, P = .001), 3.1 to 6 mm (X(2) = 13.212, df = 3, P = .004), and 9.1–12 mm (X(2) = 15.066, df = 3, P = .002). Overall, the Magnetic Resonance Imaging results yielded high sensitivity for detecting full-thickness supraspinatus tears. Considering the findings, this study may help radiologists understand the salient risk factors and identify which factors are mainly responsible for supraspinatus tendon tears and the respective grade of tear (articular partial, bursal partial, complete, or tendinopathy).