[Critical shoulder angle as a predictor of severity in rotator cuff injuries]

the connection between a critical shoulder angle (CSA) greater than 35° and the presence rotator cuff tears (RCT) is well known. However, it remains unidentified if there is an association between a higher CSA value and the presence of more severity RCT.

cross-sectional, descriptive, observational, prospective and analytical study in which patients with RCT had their CSA evaluated by imaging and the degree of the RCT by arthroscopy. Four groups were formed (without lesion; partial lesion; complete lesion; massive lesion) and were compared using ANOVA parametric statistics. The association between RCT and CSA was studied by rho Spearman coefficient.

71 patients were studied, 15 without RCT (CSA of 34.13 ± 0.98), 17 with partial lesion (CSA of 36.00 ± 1.15), 22 with complete lesion (CSA of 40.77 ± 0.69) and 17 with massive lesion (CSA of 41.53 ± 0.68). No significant statistical difference was found between the CSA of the groups without lesion and partial lesion (p = 0.486; 35°) but there was a difference between the groups with complete and massive lesion (p = 0.000 and p = 0.001; 35°). A significant positive association was found between CSA and RCT (rho = 0.605, p = 0.000).

an CSA above 35° is associated to complete and massive RCT and it works as a predictor of severity for these lesions.