基于"三法三穴"探讨推拿对坐骨神经损伤大鼠小腿肌肉生物力学特性的影响及其作用机制OA

Objective This study aimed to investigate the effects of Tuina based on the"three-manipulations and three-acu-points"protocol on the biomechanical properties of calf muscles in rats with sciatic nerve injury(SNI),and to further elucidate the mechanism underlying Tuina-mediated recovery from motor dysfunction after SNI.Methods Twenty-one male specific pathogen-free(SPF)Sprague-Dawley rats were randomly divided into the sham operation group,the SNI group,and the Tuina group using a random number table,with 7 rats in each group.The SNI model was established in the SNI and Tuina groups by crushing the sciatic nerve,while the sham operation group underwent only exposure of the nerve without clamping.At 7 days after modeling,the Tuina group received Tuina intervention using a self-developed"massage manipulation simulator"at three acupoints:Yinmen(BL37),Yan-glingquan(GB34),and Chengshan(BL57).Each acupoint was treated with three manipulations—Bo fa,Dian fa,and Rou fa—at a frequency of 60 times/min and a force of 4 N.Each manipulation was applied for 1 minute per acupoint,resulting in a total of 9 min-utes intervention per session per animal.The treatment was given once daily for 20 consecutive days,with a one-day rest after 10 days of treatment.The sham operation and SNI groups were only restrained for the same duration without any intervention.Hindlimb grip strength was evaluated using a dynamometer.The maximum Young's modulus(Emax)and maximum shear wave velocity(Smax)of the gastrocnemius,soleus,and tibialis anterior muscles were measured by shear wave elastography(SWE).The wet weight ratio of the gastrocnemius was calculated using a precision electronic balance.Morphological changes of the gastrocnemius were ob-served by Masson staining,and the cross-sectional area of muscle fibers was measured.Results Compared with the sham opera-tion group,hindlimb grip strength significantly decreased in both the SNI and Tuina groups(P<0.05);compared with the SNI group,the Tuina group showed a significant increase in grip strength(P<0.05).Compared with the sham operation group,the Emax and Smax of the gastrocnemius,soleus,and tibialis anterior muscles significantly increased in the SNI group(P<0.05),and in the Tuina group,the Emax and Smax of the gastrocnemius and tibialis anterior muscles as well as the Emax of the soleus muscle also significantly increased(P<0.05);compared with the SNI group,the Tuina group exhibited significant decreases in both Emax and Smax in all three muscles(P<0.05).Compared with the sham operation group,the wet weight ratio of the gastrocnemius was significantly reduced in both the SNI and Tuina groups(P<0.05);compared with the SNI group,the Tuina group had a significantly higher wet weight ratio(P<0.05).Masson staining revealed that in the sham operation group,the gastrocnemius muscle fibers displayed normal morphology and clear boundaries;in the SNI group,there was an increased deposition of collagen fibers between muscle bundles;in the Tuina group,the morphology of muscle fibers tended to recover,with clearer boundaries and reduced collagen fibers.Compared with the sham opera-tion group,the cross-sectional area of muscle fibers in the SNI group and the Tuina group decreased(P<0.05);compared with the SNI group,the cross-sectional area of muscle fibers in the Tuina group increased(P<0.05).Conclusion The"three-manipulations and three-acupoints"intervention could effectively alleviate SNI,restore muscle strength and elasticity of sciatic nerve innervated muscles,attenuate muscle atrophy,and recover muscle biomechanical properties,thereby improving motor dysfunction.