title: Effect of Botulinum Toxin on Clonus: A Systematic Review.
abstract: OBJECTIVE
  To conduct a systematic review of the literature that examined the effect of botulinum toxin type A on clonus.
  
  
  METHODS
  A literature search of multiple databases (PubMed, Cochrane, Google Scholar, Embase) was performed to identify articles published in English in the past 30 years (1986-2016).
  
  
  METHODS
  Two reviewers independently applied the following inclusion criteria: (1) any adult patients older than 18 years with upper motor lesion; (2) any location and duration of clonus; and (3) subjective and objective measurements of clonus tested at least 2 weeks after botulinum toxin injection.
  
  
  METHODS
  Two reviewers independently extracted the data and assessed the methodological quality. A consensus method was used to solve disagreements.
  
  
  RESULTS
  The systematic review resulted in 164 articles, of which 14 met the inclusion criteria: 3 were randomized controlled trials, 1 was nonrandomized, and 6 were case series and 3 case studies. All studies (181 patients) showed improvement in clonus: 6 of 14 results were statistically significant. Different scales were used for clonus measurement, such as clonus score, patient diaries, clonus spasm score, and electromyogram duration.
  
  
  CONCLUSIONS
  Overall, there was preliminary evidence indicating improvement in clonus after botulinum injection. The major drawback with studies reviewed here was a large variation in the type of clonus assessment tools, which also lacked validity, reliability, and sensitivity to small changes in clonus.
authors: Spasticity Research Program, West Park Healthcare Centre, Toronto, Ontario, Canada.
authors: Vivekanand
authors: V
authors: Thanikachalam
authors: Spasticity Research Program, West Park Healthcare Centre, Toronto, Ontario, Canada; Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada; Faculty of Health, York University, Toronto, Ontario, Canada. Electronic address: chetan.phadke@westpark.org.
authors: Chetan P
authors: CP
authors: Phadke
authors: Spasticity Research Program, West Park Healthcare Centre, Toronto, Ontario, Canada; Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada.
authors: Farooq
authors: F
authors: Ismail
authors: Spasticity Research Program, West Park Healthcare Centre, Toronto, Ontario, Canada; Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada.
authors: Chris
authors: C
authors: Boulias
mesh_terms: D019274:Botulinum Toxins, Type A / Q000627:therapeutic use*; D006801:Humans; D009207:Myoclonus / Q000188:drug therapy*; D009465:Neuromuscular Agents / Q000627:therapeutic use*; D015203:Reproducibility of Results
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A
keywords: Botulinum toxins; Clonus; Muscle spasticity; Rehabilitation