Schwannomas of the ulnar nerve in the hand are uncommon and those arising from the deep motor branch of the ulnar nerve (DMBUN) are rare. We were able to find only five reports of a schwannoma of the DMBUN. We report a schwannoma arising from DMBUN beyond the Guyon canal and summarise the literature on schwannomas involving the DMBUN. Level of Evidence: Level V (Therapeutic).
Keywords: Guyon canal; Motor branch ulnar nerve; Nerve tumour; Schwannoma; Ulnar nerve.