title: Hyperexcitability to electrical stimulation and accelerated muscle fatiguability of taut bands in rats.
abstract: OBJECTIVE
  Myofascial trigger points contribute significantly to musculoskeletal pain and motor dysfunction and may be associated with accelerated muscle fatiguability. The aim of this study was to investigate the electrically induced force and fatigue characteristics of muscle taut bands in rats.
  
  
  METHODS
  Muscle taut bands were dissected out and subjected to trains of electrical stimulation. The electrical threshold intensity for muscle contraction and maximum contraction force (MCF), electrical intensity dependent fatigue and electrical frequency dependent fatigue characteristics were assessed in three different sessions (n=10 each) and compared with non-taut bands in the biceps femoris muscle.
  
  
  RESULTS
  The threshold intensity for muscle contraction and MCF at the 10th, 15th and 20th intensity dependent fatigue stimuli of taut bands were significantly lower than those of non-taut bands (all p<0.05). The MCF at the 15th and 20th intensity dependent fatigue stimuli of taut bands were significantly lower than those at the 1st and 5th stimuli (all p<0.01). The MCF in the frequency dependent fatigue test was significantly higher and the stimulus frequency that induced MCF was significantly lower for taut bands than for non-taut bands (both p<0.01).
  
  
  CONCLUSIONS
  The present study demonstrates that the muscle taut band itself was more excitable to electrical stimulation and significantly less fatigue resistant than normal muscle fibres.
authors: Department of Physical Medicine and Rehabilitation, Qilu Hospital, Medical School of Shandong University, , Jinan, People's Republic of China.
authors: Yong-Hui
authors: YH
authors: Wang
authors: Ming-Jing
authors: MJ
authors: Yin
authors: Zhen-Zhen
authors: ZZ
authors: Fan
authors: Lars
authors: L
authors: Arendt-Nielsen
authors: Hong-You
authors: HY
authors: Ge
authors: Shou-Wei
authors: SW
authors: Yue
mesh_terms: D000818:Animals; D004599:Electric Stimulation Therapy; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D018763:Muscle Fatigue; D018482:Muscle, Skeletal / Q000503:physiopathology; D009209:Myofascial Pain Syndromes / Q000503:physiopathology* / Q000628:therapy*; D051381:Rats; D017208:Rats, Wistar