title: Functional effects of botulinum toxin type-A treatment and subsequent stretching of spastic calf muscles: a study in patients with hereditary spastic paraplegia.
abstract: OBJECTIVE
  Although calf muscle spasticity is often treated with botulinum toxin type-A, the effects on balance and gait are ambiguous. Hereditary spastic paraplegia is characterized by progressive spasticity and relatively mild muscle weakness of the lower limbs. It is therefore a good model to evaluate the functional effects of botulinum toxin type-A.
  
  
  METHODS
  Explorative pre-post intervention study.
  
  
  METHODS
  Fifteen subjects with pure hereditary spastic paraplegia.
  
  
  METHODS
  Patients with symptomatic calf muscle spasticity and preserved calf muscle strength received botulinum toxin type-A injections in each triceps surae (Dysport®, 500-750 MU) followed by daily stretching exercises (18 weeks). Before intervention (T0), and 4 (T1) and 18 (T2) weeks thereafter, gait, balance, motor selectivity, calf muscle tone and strength were tested.
  
  
  RESULTS
  Mean comfortable gait velocity increased from T0 (0.90 m/s (standard deviation (SD) 0.18)) to T1 (0.98 m/s (SD 0.20)), which effect persisted at T2, whereas balance and other functional measures remained unchanged. Calf muscle tone declined from T0 (median 2; range 1-2) to T1 (median 0; range 0-1), which effect partially persisted at T2 (median 1; range 0-2). Calf muscle strength did not change.
  
  
  CONCLUSIONS
  Botulinum toxin type-A treatment and subsequent muscle stretching of the calves improved comfortable gait velocity and reduced muscle tone in patients with hereditary spastic paraplegia, while preserving muscle strength. Balance remained unaffected.
authors.affiliation: Department of Rehabilitation, Centre for Evidence Based Practice and Donders Institute for Brain, Cognition, and Behaviour, Radboud, Radboud University Medical Centre, , The Netherlands.
authors.forename: Mark
authors.initials: M
authors.lastname: de Niet
authors.forename: Susanne T
authors.initials: ST
authors.lastname: de Bot
authors.forename: Bart P C
authors.initials: BP
authors.lastname: van de Warrenburg
authors.forename: Vivian
authors.initials: V
authors.lastname: Weerdesteyn
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Geurts
mesh_terms: D000328:Adult; D000368:Aged; D019274:Botulinum Toxins, Type A / Q000627:therapeutic use*; D005081:Exercise Therapy; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000503:physiopathology*; D004856:Postural Balance / Q000502:physiology; D015419:Spastic Paraplegia, Hereditary / Q000503:physiopathology* / Q000628:therapy*
chemical_list: D019274:Botulinum Toxins, Type A; C542869:abobotulinumtoxinA