Fridén J, Lieber R L
Department of Anatomy, University of Umeå, Sweden.
J Hand Surg Am. 1994 Mar;19(2):269-74. doi: 10.1016/0363-5023(94)90018-3.
Sarcomere length was measured intraoperatively using a laser diffraction method before and after surgical lengthening of the human extensor carpi radialis brevis muscle (ECRB) in five subjects treated for lateral epicondylitis. Based on measured sarcomere and filament lengths, we previously established the length-tension curve for this muscle and the normal sarcomere length range as a function of wrist joint angle. Preoperative measurements indicated that the ECRB developed near-maximal isometric force at full wrist extension, decreasing to 20% maximum at full wrist flexion. Stair-step surgical tendon lengthening of the ECRB by 9.1 mm resulted in mean ECRB sarcomere shortening of 0.30 microns. This 0.30 microns shortening was predicted to have two primary biomechanical effects: (1) a 25% decrease in muscle passive tension that could lead to reduced insertional tension and decreased pain and (2) a 25% increase in active muscle force that opposes the notion that tendon lengthening necessarily results in muscle weakness.
在五名接受外侧上髁炎治疗的受试者中，术中使用激光衍射法测量了桡侧腕短伸肌（ECRB）手术延长前后的肌节长度。基于测量的肌节和细丝长度，我们之前建立了该肌肉的长度-张力曲线以及正常肌节长度范围与腕关节角度的函数关系。术前测量表明，ECRB在腕关节完全伸展时产生接近最大的等长力，在腕关节完全屈曲时降至最大值的20%。ECRB进行9.1毫米的阶梯式手术肌腱延长导致平均ECRB肌节缩短0.30微米。预计这0.30微米的缩短会产生两个主要的生物力学效应：（1）肌肉被动张力降低25%，这可能导致插入张力降低和疼痛减轻；（2）主动肌肉力量增加25%，这与肌腱延长必然导致肌肉无力的观点相悖。
