兔肌肉移位中张力调节与功能恢复的实验性研究

Experimental research of the relationship between tension adjusting and functional recovery in muscle transfer of rabbit

目的探讨肌肉移位术中肌肉张力大小与术后肌肉功能恢复的相关性，并确定肌小节长度是表达肌肉张力可靠指标，为临床肌肉移位术中通过调节肌张力以优化术后肌肉功能提供依据并指导临床应用。方法将家兔趾长屈肌移位缝合于胫骨前肌腱远端建立肌肉转位模型，于术后3个月活体取下趾长屈肌测量肌肉收缩能力、肌湿重维持率等与未改变长度和张力的正常状态组进行对比研究，并与对照侧对比观察肌纤维微观形态。结果术后3个月的肌肉收缩能力、肌肉湿重恢复率均随着术中肌小节长度及肌肉长度相对变化比的增加呈现先增加后降低的趋势；肌小节长度随着肌肉变化相对比增加而增加，肌小节长度与肌肉张力变化相对比呈正相关。结论家兔肌肉移位术中，随肌肉张力逐渐增加术后肌肉功能呈现先增加后缓慢下降的趋势；最佳的术中肌肉张力不是在固定在休息位或更低肌肉长度和张力时，而是在相当于休息位肌肉长度的104％～105％；肌小节长度可作为体现肌肉张力、优化肌肉功能的可靠指标。

Objective To explore the relationship between muscle tension and recovery of function during muscle transfer, and attempt to demonstrate that the sarcomere length is also a reliable indicator of muscle tension, which can be used to optimize muscle function. Methods 10 male SD rabbits were used. The flexor digitorum longus muscle was cut distally and transferred and woven into the tibiatis anterior tendon. Resting and transferred muscle length, sarcomere lengths were measured during the operation. Both flexor digitorum longus muscles of 10 rabbits were harvested and muscle contractive capacity and muscle wet weight maintenance rate, architectural analysis were detected in comparison the group under normal condition without changing length and tension 3 months after operation. The micro pattern was observed by comparison. Result With the increase of the intraoperative sarcomere length and muscle length relative ratio, the value of muscle contractive capacity and muscle wet weight maintenance rate after 3 months increases in the early stages and then decreased; Sarcomere length increasesas along with muscle length relative ratio; the relationship between them demonstrated a linear correlation as shown by linear regression analysis. Conclusion Following a long-term recovery period, a muscle set with increased tension contracts with better recovery of muscle function and negligible adverse effects to muscle fibers; Muscles produce maximum tensions at just over resting length, at about 104%-105% of resting length. The sarcomere length can be used as a characterization of muscle tension and proved to be an excellent predictor of active muscle force generated.