Correlation of acromial morphology in association with rotator cuff tear: a retrospective study

PURPOSE: There have been many studies that have attempted to correlate radiographic acromial characteristics with rotator cuff tears, but the results have not been conclusive. Rotator cuff tears (RCT) are the common aetiology of shoulder pain. We assessed the association of rotator cuff tears with commonly used radiographic parameters of acromial morphology and their different radiographic characteristics. MATERIAL AND METHODS: From a retrospective study of 98 patients, we characterised acromial type and measured acromial thickness (AT), critical shoulder angle (CSA), lateral acromial angle (LAA), acromiohumeral distance (AHD), and acromion index (AI) on a 1.5T MRI, from 68 patients with partial or full-thickness supraspinatus tendon tears and 30 controls without tears. RESULTS: Out the 68 patients with rotator cuff tear, supraspinatus was the most commonly affected tendon, with 86% (59) cases showing abnormalities. The average age of the patients was 45.11 ± 21.45 years with male dominance (80%). Partial tears of rotator cuff were more common than complete tears. Forty-eight cases showed partial tears in supraspinatus as compared to 11 cases of complete tears. The acromial type did not show any correlation with any particular cuff lesion. The AT and AI of controls were significantly smaller than cuff-tear patients. The LAA of cuff-tear patients was significantly different from that of control patients. The impingement patients demonstrated a significantly greater acromial thickness, larger CSA, decreased AHD, and decreased LAA than their control counterparts. CONCLUSIONS: A higher prevalence of rotator cuff tears and impingement associated with low lateral acromial angle, larger CSA and decreased AHD was observed. AT and AI have a direct correlation with rotator cuff tear.