Immediate effects of acupuncture on biceps brachii muscle function in healthy and post-stroke subjects

• Main Authors: Fragoso Ana (Author), Ferreira Arthur S (Author)
• Format: Book
• Published: BMC, 2012-03-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

<p>Abstract</p> <p>Background</p> <p>The effects of acupuncture on muscle function in healthy subjects are contradictory and cannot be extrapolated to post-stroke patients. This study evaluated the immediate effects of manual acupuncture on myoelectric activity and isometric force in healthy and post-stroke patients.</p> <p>Methods</p> <p>A randomized clinical trial, with parallel groups, single-blinded study design, was conducted with 32 healthy subjects and 15 post-stroke patients with chronic hemiparesis. Surface electromyography from biceps brachii during maximal isometric voluntary tests was performed before and after 20-min intermittent, and manual stimulation of acupoints <it>Quchi </it>(LI11) or <it>Tianquan </it>(PC2). Pattern differentiation was performed by an automated method based on logistic regression equations.</p> <p>Results</p> <p>Healthy subjects showed a decrease in the root mean-squared (RMS) values after the stimulation of LI11 (pre: 1.392 ± 0.826 V; post: 0.612 ± 0.0.320 V; <it>P </it>= 0.002) and PC2 (pre: 1.494 ± 0.826 V; post: 0.623 ± 0.320 V; <it>P </it>= 0.001). Elbow flexion maximal isometric voluntary contraction (MIVC) was not significantly different after acupuncture stimulation of LI11 (pre: 22.2 ± 10.7 kg; post: 21.7 ± 9.5 kg; <it>P </it>= 0.288) or PC2 (pre: 18.8 ± 4.6 kg; post: 18.7 ± 6.0 kg; <it>P </it>= 0.468). Post-stroke patients did not exhibit any significant decrease in the RMS values after the stimulation of LI11 (pre: 0.627 ± 0.335 V; post: 0.530 ± 0.272 V; <it>P </it>= 0.187) and PC2 (pre: 0.601 ± 0.258 V; post: 0.591 ± 0.326 V; <it>P </it>= 0.398). Also, no significant decrease in the MIVC value was observed after the stimulation of LI11 (pre: 9.6 ± 3.9 kg; post: 9.6 ± 4.7 kg; <it>P </it>= 0.499) or PC2 (pre: 10.7 ± 5.6 kg; post: 10.2 ± 5.3 kg; <it>P </it>= 0.251). Different frequency of patterns was observed among healthy subjects and post-stroke patients groups (<it>χ</it>²= 9.759; <it>P </it>= 0.021).</p> <p>Conclusion</p> <p>Manual acupuncture provides sufficient neuromuscular stimuli to promote immediate changes in motor unit gross recruitment without repercussion in maximal force output in healthy subjects. Post-stroke patients did not exhibit significant reduction on the myoelectric activity and maximal force output after manual acupuncture and needs further evaluation with a larger sample.</p> <p>Trial registration</p> <p>Brazilian Clinical Trials Registry RBR-5g7xqh.</p>

Item Description

10.1186/1749-8546-7-7
1749-8546