Ann Rehabil Med.  2015 Aug;39(4):654-658. 10.5535/arm.2015.39.4.654.

A Patient With Focal Dystonia That Occurred Secondary to a Peripheral Neurogenic Tumor: A Case Report

• Park M
• Kim HS
• Lee JH
• Yun DH
• Chon J
• Han YJ

• KMID: 2148240
• DOI: http://doi.org/10.5535/arm.2015.39.4.654

Abstract

Dystonia is a movement disorder characterized by involuntary muscle contractions. Patients with dystonia may experience uncontrollable twisting, repetitive movements, or abnormal posture. A 55-year-old man presented with an involuntary left forearm supination, which he had experienced for five years. There was no history of antecedent trauma to the wrist or elbow. Although conventional therapeutic modalities had been performed, the symptoms persisted. When he visited our hospital, electromyography was performed. Reduced conduction velocity was evident at the elbow-axilla segment of the left median nerve. We suspected that there was a problem on the median nerve between the elbow and the axilla. For this reason, we performed an ultrasonography and magnetic resonance imaging study. A spindle-shaped soft tissue mass was observed at the left median nerve that suggested the possibility of neurofibroma. Dystonia caused by traumatic or compressive peripheral nerve injury has often been reported, but focal dystonia due to a neurogenic tumor is extremely rare. Here, we report our case with a review of the literature.

Keyword

Dystonia; Neurofibroma; Median neuropathy

MeSH Terms

Axilla
Dystonia
Dystonic Disorders*
Elbow
Electromyography
Forearm
Humans
Magnetic Resonance Imaging
Median Nerve
Median Neuropathy
Middle Aged
Movement Disorders
Muscle, Smooth
Neurofibroma
Peripheral Nerve Injuries
Posture
Supination
Ultrasonography
Wrist

Figure

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  Fig. 1 Clinical presentation. (A) Involuntary forearm supination with elbow flexed at 90°. (B) He had to type on a keyboard by raising his elbow due to forearm supination.

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  Fig. 2 Cervical magnetic resonance image taken at another hospital. (A) Sagittal image demonstrates disc space narrowing at C5-6 and multi-level disc protrusion. (B) Axial image demonstrates right paracentral disc protrusion at C5-6 level.

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  Fig. 3 Imaging study of left upper extremity. (A) Longitudinal ultrasonographic scan of distal arm demonstrates nodular shaped mass in the median nerve. (B) T1 sagittal image with gadolinium enhancement demonstrates a high signal nodular lesion at the distal arm. (C) T1 transverse image with gadolinium enhancement demonstrates a high signal target appearance mass in the median nerve at the distal arm.

Reference

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