Application of the hierarchical SCT to brachial plexus injury (corresponds to Video, Supplementary Digital Content 2, https://vimeo.com/59943111). This patient had a right medial cord injury and on physical examination had significantly more wasting of the ulnar-innervated intrinsic muscles as compared to the median-innervated intrinsics. A multilevel injury was suspected, and a hierarchical SCT was performed to determine secondary entrapment points on the ulnar nerve. The sequence of collapse in this patient was the right thoracic outlet (consistent with the medial cord injury), followed by the deep motor branch of the ulnar nerve, cubital tunnel, volar antebrachial fascia, and the arcade of Struthers