Recurrent Ulnar Nerve Schwannoma in the Cubital Tunnel Elbow: A Rare Presentation and Surgical Management.

Schwannoma is a benign tumor arising from Schwann cells of peripheral nerves. Although recurrence is rare, this case report highlights a unique instance of recurrent ulnar nerve schwannoma in a 76-year-old construction worker, emphasizing the complexities of surgical management. The patient presented to our orthopedic clinic with persistent pain and tingling in the medial aspect of his left forearm and hand for the past two years. His medical history included bilateral ulnar nerve schwannoma excision at the cubital tunnel level 20 years prior. Examination revealed a firm, non-tender swelling measuring 5 × 5 cm on the medial side of the left distal arm, with neurological assessment indicating reduced sensation in the little finger and medial half of the ring finger, as well as intrinsic hand muscle weakness. His preoperative Disabilities of the Arm, Shoulder, and Hand (DASH) score was 65, reflecting substantial functional limitations. Preoperative nerve conduction studies confirmed ulnar nerve damage, and MRI indicated a tumor originating from the left ulnar nerve. Given the tumor's increasing size, surgical excision was done. The procedure involved careful dissection around the elbow to isolate the ulnar nerve, significantly affected by fibrosis from prior surgeries. We performed macro neurolysis, which decompresses larger segments of the nerve, and micro neurolysis, which allows for precise intervention on specific segments, to effectively address the challenges presented by the scar tissue. Anterior transposition of the ulnar nerve was conducted to place it in an unscarred area, reducing compression and promoting nerve function. The postoperative biopsy confirmed a benign schwannoma characterized by localized Antoni A and Antoni B areas. Six months post surgery, the patient reported complete resolution of symptoms, with grip strength improving to approximately 95% of normal and a postoperative DASH score of 25. Follow-up assessments showed enhanced nerve function, with no signs of tumor recurrence over two years. This case underscores the challenges of managing recurrent ulnar nerve schwannoma and emphasizes the critical role of surgical intervention in preserving nerve function and improving patient outcomes. The successful management of this recurrence highlights the importance of meticulous surgical technique and thorough follow-up in ensuring long-term patient well-being.