title: A Case of Action-Induced Clonus that Mimicked Action Tremors and was Associated with Cervical Schwannoma.
abstract: Clonus is the rhythmic muscle contraction which usually occurs in patients with lesions involving descending motor pathways. Sometimes, rhythmic oscillation of action induced clonus could be confused to action tremor. We report a case of action induced clonus associated with cervical schwannoma which was misdiagnosed as essential tremor. The patient had spasticity in all limbs with exaggerated tendon reflexes, and passive stretch-induced clonus. Imaging and histological examinations revealed a schwannoma extending from C2 to C7. The lesion was partially removed by surgery. Even though essential tremor is a common disease, clinician have to do sufficient neurologic examination considering differential diagnosis.
authors.affiliation: Department of Neurology, Gachon University College of Medicine, Incheon, Korea.
authors.forename: Young-Hee
authors.initials: YH
authors.lastname: Sung
authors.affiliation: Department of Neurology, Gachon University College of Medicine, Incheon, Korea.
authors.forename: Ki-Hyung
authors.initials: KH
authors.lastname: Park
authors.affiliation: Department of Neurology, Gachon University College of Medicine, Incheon, Korea.
authors.forename: Yeung-Bae
authors.initials: YB
authors.lastname: Lee
authors.affiliation: Department of Neurology, Gachon University College of Medicine, Incheon, Korea.
authors.forename: Hyeon-Mi
authors.initials: HM
authors.lastname: Park
authors.affiliation: Department of Neurology, Gachon University College of Medicine, Incheon, Korea.
authors.forename: Dong-Jin
authors.initials: DJ
authors.lastname: Shin
keywords: Action-induced clonus; Cervical schwannoma