Posterior interosseous nerve palsy caused by a parosteal lipoma seated over the proximal radius; a case report and review of the literature

Abstract

Several different pathologies may play a role in the etiology of posterior interosseous nerve (PIN) palsy such as trauma,radial tunnel syndrome, tumors, vasculitis, septic arthritis, and rheumatoid synovitis. The most common atraumatic factoris the compression of the nerve through its anatomic path. Parosteal lipoma around the proximal radius is the leading solidtumor seen among the neoplastic lesions. Although it is common, there are only case reports or few case series reportedin the current literature and a comprehensive review is missing. Herein a rare case of PIN palsy due to parosteal lipoma ofthe proximal radius is presented together with a thorough literature review. A 48-year-old woman was presented with elbowpain and wrist drop that lasted for ten months. Electrodiagnostic and imaging findings lead to a diagnosis of PIN palsydue to parosteal lipoma seated over the proximal radius. Total surgical excision was performed, and the patient had beenfollowed up for one year. Removal of the lipoma failed to recover the patient’s symptoms. We reviewed all the reportedcases and discussed, epidemiology, clinical findings, imaging studies, electrodiagnostic studies, pathology, treatment andprognosis of PIN palsy due to parosteal lipoma.