Intramuscular schwannoma presenting as treatment-resistant lumbar radiculopathy: Case report

Abstract

Intramuscular schwannomas are rare tumors originating from Schwann cells in the peripheral nervous system. These tumors typically occur along small motor nerves deep within the muscle, presenting diagnostic challenges for clinicians due to their rarity and nonspecific symptoms. They can induce pain that is resistant to interventions, and surgical removal is often the only method that provides relief of symptoms. We present a case of a 65-year-old male with low back pain and concurrent right anterior thigh pain and paresthesia. Despite extensive evaluation by numerous specialists and thorough diagnostic testing, including spinal MRIs and electrodiagnostic studies, no clear diagnosis was initially established. His symptoms remained resistant to medical and interventional treatments. Ultimately, MRI imaging of the right thigh revealed a mass measuring approximately 2 cm in the vastus medialis. Following excision of the mass, the patient experienced immediate symptom relief. This case highlights the importance of maintaining a broad differential when evaluating low back pain with associated lower extremity symptoms. We aim to highlight the importance of recognizing this possibility of extra-spinal pain generators.