Intramuscular Myxoma of the Flexor Carpi Ulnaris Causing Cubital Tunnel Syndrome: A Case Report

Intramuscular myxomas are rare, benign mesenchymal tumors which commonly arise in muscle of the upper limb, pelvis, abdominal tissue, spine, or facial muscle. There are few case reports of intramuscular myxomas, and none of these describe intramuscular myxoma as a cause of compressive neuropathy.

We describe the case of a 67-year-old woman who presented to us with a 1-year history of progressive enlargement of a painless right elbow mass. She gradually developed increasing numbness and tingling in her right small finger, which was worse at night. She underwent cubital tunnel release with concurrent right elbow mass excision of the flexor carpi ulnaris muscle. Histology showed intramuscular myxoma. Postoperatively, she had a complete resolution of her symptoms with a good functional outcome.

This is the first known case of intramuscular myxoma within the flexor carpi ulnaris causing compressive neuropathy of the ulnar nerve at the elbow.