MRI
T2 hyperintense pseudomeningoceles are seen at C6/C7 and C7/T1 around avulsed C7 and T1 nerve roots on the left. No intrinsic cord signal abnormality.There appears to be complete disruption of the roots of the left brachial plexus immediately beyond the scalene muscles. Redundant brachial plexus is seen beyond this. Moderate amount of oedema within the soft tissues of the lateral neck on the left, particularly involving the scalenes musculature. The cervical spine demonstrates no evidence of malalignment or abnormal bone marrow signal. Small left shoulder joint effusion. Denervation oedema seen in the muscles around the scapula.
Conclusion: Complete disruption of the roots of the left brachial plexus. Left C6/C7 and C7/T1 pseudo-meningocoeles around avulsed left C7 and T1 nerve roots.