This article presents a 48-year-old male patient who presented with pain in the left forearm andweakness and clumsiness in the left hand of 6 months' duration. Flexor motor strength loss of the thumband the indexŞnger was present and neurophysiologic tests showed Şndings compatible with axonalinjury in the anterior interosseous nerve (AIN) innervated muscles. Magnetic resonance imagingrevealed a space-occupying lesion in the proximal forearm resembling a glomus tumor. Excision of themass and release of the AIN were performed. Histopathology conŞrmed a glomus tumor, and the patientremains asymptomatic at 1 year postoperatively. We stress the importance of imaging studies in patientswhen a suspected secondary nature of nerve entrapment is present.
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