Focal myositis presenting with radial nerve palsy.
Focal myositis is a rare inflammatory pseudotumor of skeletal muscle which usually has a benign course. We report a 56-year-old woman with a painful mass in the left arm with a radial nerve palsy. Magnetic resonance imaging (MRI) of the left arm showed a mass in the triceps muscle that was suggestive of a soft-tissue sarcoma. Electromyography showed a severe radial neuropathy involving both motor and sensory axons. An open biopsy showed focal myositis. Treatment with corticosteroids resulted in complete disappearance of the mass clinically and by MRI, without recurrence for more than 2 years. Radial nerve function also recovered completely. As a treatable cause of focal neuropathy, focal myositis should be included in the differential diagnosis of a muscle mass.
Alzagatiti
B I
BI
Department of Neurology, University of Tennessee Memphis, and Methodist Hospitals of Memphis, 855 Monroe Avenue, Room 415, Memphis, Tennessee 38163, USA.
Bertorini
T E
TE
Horner
L H
LH
Maccarino
V S
VS
O'Brien
T
T
D004576:Electromyography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009220:Myositis / Q000150:complications / Q000175:diagnosis*; D010243:Paralysis / Q000503:physiopathology*; D011826:Radial Nerve / Q000503:physiopathology*