Orishimo Karl F, Burstein Gideon, Mullaney Michael J, Kremenic Ian J, Nesse Marcus, McHugh Malachy P, Lee Steven J
Nicholas Institute of Sports Medicine and Athletic Trauma, 130 E. 77th Street, 10th Floor, New York, NY 10021, USA.
J Foot Ankle Surg. 2008 Jan-Feb;47(1):34-9. doi: 10.1053/j.jfas.2007.10.008.
Early mobilization exercises are advocated following Achilles tendon (AT) repair, but forces on the repair during passive range of motion are unknown. The extent to which these forces change with flexion of the knee is also not known. Estimated AT forces were measured using 3 models: cadaveric, uninjured subjects, and in both legs of subjects 6 weeks following unilateral AT repair. For cadaveric testing, estimated AT force was recorded using a force transducer while cycling the ankle from 10 degrees plantarflexion to maximum dorsiflexion at 3 different knee flexion angles (0 degrees , 45 degrees , and 90 degrees ). For in vivo testing, subjects were seated in an isokinetic dynamometer, and their ankles passively cycled from plantarflexion to dorsiflexion with the knee extended and flexed 50 degrees . Passive plantarflexion moment recorded by the dynamometer was converted to AT force by estimating the AT moment arm. In the cadaveric model, knee flexion reduced estimated AT forces during dorsiflexion by more than 40% (P < .036). In vivo testing showed that estimated AT force was reduced in knee flexion in healthy subjects (P < .001) and in the uninvolved leg AT repair subjects (P = .021), but not in the AT repaired leg (P = .387). Normal AT showed a marked reduction in estimated AT force with knee flexion which was not present in repaired AT. This could be because of elongation of the repair, causing more slack in the tendon that would need to be taken up before force transmission occurs. ACFAS Level of Clinical Evidence: 4.
跟腱（AT）修复术后提倡早期进行活动锻炼，但被动活动范围内修复部位所受的力尚不清楚。这些力随膝关节屈曲而变化的程度也未知。使用3种模型测量了跟腱估计受力：尸体模型、未受伤受试者以及单侧跟腱修复术后6周受试者的双腿。对于尸体测试，在3个不同膝关节屈曲角度（0度、45度和90度）下，将踝关节从跖屈10度循环至最大背屈时，使用力传感器记录跟腱估计受力。对于活体测试，受试者坐在等速测力计上，在膝关节伸展和屈曲50度的情况下，其踝关节被动地从跖屈循环至背屈。通过估计跟腱力臂，将测力计记录的被动跖屈力矩转换为跟腱力。在尸体模型中，膝关节屈曲使背屈过程中的跟腱估计受力降低了40%以上（P <.036）。活体测试表明，健康受试者（P <.001）和未受伤侧跟腱修复受试者（P =.021）在膝关节屈曲时跟腱估计受力降低，但跟腱修复侧没有降低（P =.387）。正常跟腱在膝关节屈曲时跟腱估计受力显著降低，而修复后的跟腱则没有。这可能是由于修复部位伸长，导致肌腱松弛更多，在力传递发生之前需要更多的松弛部分被拉紧。ACFAS临床证据等级：4级。
