Cubital tunnel syndrome caused by an intraneural ganglion cyst treated with epineurectomy: a report of three cases

The potential causes of cubital tunnel syndrome include trauma, bone deformity, and space-occupying lesions such as tumors. An intraneural ganglion is a cystic tumor composed of a fibrous capsule containing mucinous material within the epineurium of a peripheral nerve, and it most commonly occurs in the peroneal nerve. However, cases of intraneural ganglion cysts occurring at the elbow, leading to cubital tunnel syndrome in the ulnar nerve, have been rarely reported. Cubital tunnel syndrome caused by an intraneural ganglion differs in its pathogenesis from idiopathic nerve entrapment syndrome; thus, it requires distinct approaches for diagnosis and treatment. In this context, the authors report three cases of cubital tunnel syndrome caused by intraneural ganglia. Favorable outcomes were achieved through partial epineurectomy and in situ decompression. Additionally, a review of the literature is presented.