Myofibroma mimicking peripheral nerve sheath tumour with ulnar nerve compression symptoms. Issue 2 (2nd February 2023)

• Record Type: Journal Article
• Authors: Chim, Harvey; Wiesemann, Gayle Suk; Nasri, Elham
• Is Part Of: BMJ case reports. Volume 16:Issue 2(2023)
• Publication Date: 2023-02-02
• Subjects: Plastic and reconstructive surgery -- Orthopaedic and trauma surgery -- Tendonopathies -- Orthopaedics -- Peripheral nerve disease; Medicine -- Case studies -- Periodicals; 610.5
• DOI: 10.1136/bcr-2022-252939
• Languages: English
• ISSNs: 1757-790X

Abstract

Abstract : We report a case of myofibroma encasing the ulnar nerve on the medial aspect of the left arm with motor and sensory deficit secondary to compression. Initially, the tumour appeared to be a benign peripheral nerve sheath tumour based on preoperative imaging, with clinical examination positive for left hand clawing and a positive Wartenberg's and Froment's sign. However, intraoperative dissection demonstrated that the mass did not originate from the ulnar nerve proper, lowering suspicion for a peripheral nerve sheath tumour. Histopathological analysis showed spindle cell neoplasm, consistent with myofibroma. The patient underwent hand occupational therapy subsequently, with improvement of grip strength from 5 lb to 12 lb by 4 months postoperatively and resolution of clawing of the hand postoperatively. We discuss differentiating features for this rare occurrence of solitary adult myofibroma, where the final diagnosis was only made after formal histopathological analysis.