Botulinum toxin treatment of muscle cramps: A clinical and neurophysiological study

✍ Scribed by Dr Laura Bertolasi; Alberto Priori; Giuliano Tomelleri; Luigi G. Bongiovanni; Emiliana Fincati; Alessandro Simonati; Domenico De Grandis; Nicolo' Rizzuto

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 574 KB
• Volume: 41
• Category: Article
• ISSN: 0364-5134
• DOI: 10.1002/ana.410410209

✦ Synopsis

Abstract

Botulinum toxin is now widely used in the treatment of severla hyperkinetic movement disorders. To evaluate its efficacy in treating muscle cramping syndromes, we studied clinical and neurophysiological variables before and after botulinum toxin injections into calf muscles and small flexor muscles of the foot in patients with an inherited benign crampfasciculation syndrome. At each assessment the clinical severity of cramp was scored and the cramp threshold frequency was measured with repetitive electrical peripheral nerve stimulation. Botulinum toxin injection signifcantly lowered our patients' clinical cramp severity scores (mean ± SD: before, 3.80 ± 0.44; after, 1.40 ± 0.54), left muscle strength unchanged and significanlty increased their cramp threshold frequencies (before, 4.22 ± 2.26 Hz; after, 10.0 ± 3.74 Hz). The clinical beefit induced by botulinum toxin lasted about 3 months. Boutlinum toxin injections also significantly reduced fasciculation potentials in relaxed muscles (before, 0.86 ± 0.19 fasciculations/sec; after, 0.45 ± 0.11 fasciculations/sec). These findings show that local intramuscular injection of botulinum toxin provide effective, safe, and long‐lasting relief of cramps possibly by reducing presynaptic cholinergic stimulation of motor nerve terminals and by impairing the input/output function of intrafusal and extrafusal motor end plates.