Journal international de médecine physique et de réadaptation
Libre accès
ISSN: 2329-9096
ISSN: 2329-9096
Yosuke Iwamoto, Naohisa Miyakoshi, Toshiki Matsunaga, Daisuke Kudo, Kimio Saito, Junpei Iida, Yasuhiro Takahashi, Junichi Inoue, Motoki Mita, Shohei Murata, Rena Wakabayashi and Yoichi Shimada
Objective: To investigate the effect of frequency-modulated repetitive peripheral magnetic stimulation (rPMS) for disuse muscle atrophy in the animal model.
Methods: Thirty-five 6-week-old male SD rats were randomly assigned to 5 groups: the control group (C group), 20-Hz constant-stimulation group (20 Hz group), 5-Hz constant-stimulation group (5 Hz group), 20-Hz/5-Hz modulated-stimulation group (20 Hz/5 Hz group), and non-stimulation group (N group). Atrophy of hind limb muscles was induced by tail suspension for 5 weeks. For the stimulation groups, rPMS to the right sciatic nerve were performed for 30 min a day for 2 weeks. Variables assessed were isometric maximum muscle contraction force and the degree of muscle fatigue of the soleus muscle, muscle weight of tibialis anterior.
Results: The isometric maximum muscle tension was 28.5 ± 3.8 in the 20 Hz group, 20.1 ± 3.8 in the 5 Hz group, 30.6 ± 2.8 in the 20 Hz/5 Hz group, and 21.1 ± 2.3 in the N group. Muscle fatigue in the 20 Hz and the 20 Hz/5 Hz group was significantly lower than in the N group (p <0.05). Muscle weight was 0.56 ± 0.09 in the 20 Hz group, 0.45 ± 0.91 in the 5 Hz group, 0.67 ± 0.79 in the 20 Hz/5 Hz group, and 0.42 ± 0.71 in the N group.
Conclusion: The 20-Hz/5-Hz frequency-modulated rPMS for atrophied leg muscles in the rat tail suspension model improved muscle atrophy equal to or better than 20-Hz constant-frequency stimulation and more than 5-Hz constant-frequency stimulation.