Abstract
BACKGROUND: Previous research has established connections between the acromion index (AI), critical shoulder angle (CSA), acromiohumeral distance (AHD), and lateral acromion angle (LAA) with the incidence of rotator cuff tears (RCTs). Despite numerous international studies exploring the variability of shoulder joint morphology and parameters, research incorporating these parameters has yet to be conducted in Somalia. This study aims to analyze and describe the radiological parameters of acromion morphology in the Somali populations. Furthermore, to investigate the relationship of these parameters with rotator cuff tears within the Somali population. METHODS: The data and physical examination of 188 patients who had a CT scan of the shoulder from 2018 to 2023 were retrospective analyses, including 107 patients (49 females, 58 males) with RCT and 81 patients (20 females, 61 males) with non-RCT. Using Three-dimensional computed tomography (3D-CT), parameters such as the AI, CSA, AHD, and LAA were compared between the RCT and non-RCT groups. Two independent assessors measured Each parameter from anterior views of the scapula. The inter- and intra-observer reliability was evaluated using the intraclass correlation coefficient (ICC). Additionally, the relationship between these parameters and the presence of rotator cuff tears was explored, and the predictive value of each parameter was assessed through receiver operating characteristic (ROC) analysis. RESULTS: The results showed excellent intra- and inter-observer reliability, with all ICC values above 0.75. Among these, the CSA exhibited the greatest measurement stability, with an intra-observer ICC of 0.929 and an inter-observer ICC of 0.911. Significant positive correlations were identified between the AI, CSA, and the presence of RCTs, with CSA exhibiting the strongest correlation (r = 0.629; P < 0.001). Additionally, significant negative correlations were found between the presence of RCTs and both AHD (-0.247) and LAA (-0.338; P < 0.001 for both). The ROC analysis revealed that the CSA is the most effective parameter for identifying the presence of RCT (area under the ROC curve. 0.857). CONCLUSION: The outcome of this study shows that AI, CSA, AHD, and LAA are independent factors associated with rotator cuff tears in the East African, particularly the Somali population. Specifically, larger AI, CSA, and smaller AHD and LAA are correlated with an increased likelihood of RCTs in this population. In patients with shoulder disease suspected of RCTs, using a 3D-CT scan to measure the CSA may be helpful, as it is the best predictor measurement. CLINICAL TRIAL NUMBER: Not Applicable.