Reliable MRI and MRN signs of nerve and muscle injury following trauma to the shoulder with EMG and Clinical correlation

Purpose: To evaluate the role of MRN in diagnosis of suprascapular nerve injury and its relation with muscle injury after shoulder trauma in comparison with the EMG results. Patient & method: The study was carried on 30 patients following trauma to the shoulder, either direct trauma (80%) or indirect trauma in 20% presented clinically with shoulder pain and limited movements and referred for MRI examination. The MRI results were correlated with EMG results for all cases. Results: Those 30 cases were divided into 13 cases with acute onset, 10 cases with subacute onset and 7 cases with chronic onset. In acute injuries, 5 cases (5/30) showed combined nerve and muscle injuries, 4 cases (4/30) showed nerve injury only and 5 cases (5/30) showed muscle injury only. In subacute injuries 5 cases (5/30) showed combined muscle and nerve injuries and 5 cases (5/30) showed muscle injury only, in chronic 7 cases (7/30) showed combined nerve and muscle injuries, where EMG showed sharp waves only in 7 cases which are all chronic. Conclusion: MRN is the best modality in diagnosis of nerve injuries and associated muscle injuries in one sitting with no obvious difficulties in the examination. MRN associating with the routine MRI elevated the sensitivity of diagnosis.