Prevalence and Correlation between MRI Findings and Outcome of Conservative Treatment in Primary Idiopathic Frozen Shoulder

Objectives: Primary idiopathic frozen shoulder (FS) causes pain and stiffness in the shoulder joint. Over time, this disease causes restriction of shoulder motion. We undertook this study to evaluate possible correlation of MRI findings with outcome of conservative management in FS.Methods: A total of ۶۵ cases participated in prospective cohort study. The correlation of MRI findings obtained before commencing the treatment with outcome of non-operative management (Mean of ROM, VAS, SST and OSS) was evaluated.Results: Anterior extracapsular edema significantly correlated with FF, EXR, VAS (a) and OSS. The effusion in humeral side of axillary recess significantly correlated with ROM restriction in ABD, EXR. Capsular thickness of glenoid portion showed good significance with FF, ABD, VAS (a) and OSS. Increased thickness of CHL showed negative correlation with improvement of EXR (P=۰.۰۴۹) (r=-۰.۶۱۷). Thickening of IGHL showed negative correlation with improvement of ABD (p=۰.۰۰۵ r=-۰.۸۶۲) and FF (p=۰.۰۰۷ r=-۰.۸۳۱). Mean Height of Axillary recess (HAR) was ۷.۲mm (۳.۵-۱۱mm). HAR showed negative correlation with VAS pain scale (P=۰.۰۳۶) (r=-۰.۶۸۲) and OSS (P=۰.۰۳۸) (r=-۰.۶۶۸)Conclusion: Thickness of the joint capsule and effusion at the axillary fold are important factors for refractory frozen shoulder. We can recommend MRI for refractive cases and low threshold of expectation can be set for conservative management in patients with above findings. Level of evidence: III