title: Effect of cold application and tizanidine on clonus: clinical and electrophysiological assessment.
abstract: OBJECTIVE
  Clonus is an involuntary rhythmic muscle contraction after sudden muscle stretch that occurs as a result of a lesion in the upper motor neurons. The real mechanism behind clonus remains obscure. The objective of this study was to investigate the effects of central-acting tizanidine treatment and peripheral extremity cooling on clonus.
  
  
  METHODS
  Thirty-eight patients with upper motor neuron involvement and sustained clonus.
  
  
  METHODS
  The 38 patients were divided into 3 groups: cold group (n=19), tizanidine group (n=13), and patient control group (n=6). A separate group of 21 able-bodied volunteers served as controls for the cold group. The physiologic effects of cold application were measured in the able-bodied group and compared with the effects in the patients in the cold group. All participants were evaluated by clinical and electrophysiologic measurements.
  
  
  RESULTS
  Changes in clinical and electrophysiologic measurements in the cold group were statistically significant compared with those of the tizanidine and patient control groups.
  
  
  CONCLUSIONS
  Subsequent and long-term cold application induced prolonged inhibitory effects on clonus. Tizanidine had no significant effect on clonus. Suppression of clonus by cold highlights the importance of peripheral input in relation to central mechanisms.
authors: Department of Physical Medicine and Rehabilitation, Ankara Physical Medicine and Rehabilitation Education and Research Hospital, Ankara, Turkey.
authors: Ismail
authors: I
authors: Boyraz
authors: Fugen
authors: F
authors: Oktay
authors: Canan
authors: C
authors: Celik
authors: Mufit
authors: M
authors: Akyuz
authors: Hilmi
authors: H
authors: Uysal
mesh_terms: D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use*; D003000:Clonidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D017679:Cryotherapy / Q000379:methods*; D004576:Electromyography / Q000379:methods; D005260:Female; D006181:H-Reflex / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009207:Myoclonus / Q000503:physiopathology* / Q000628:therapy*; D009431:Neural Conduction / Q000187:drug effects / Q000502:physiology; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; C023754:tizanidine; D003000:Clonidine