Shultz Sandra J, Shimokochi Yohei, Nguyen Anh-Dung, Schmitz Randy J, Beynnon Bruce D, Perrin David H
Applied Neuromechanics Research Laboratory, Department of Exercise and Sport Science, University of North Carolina at Greensboro, 237B HHP Building, P.O. Box 26170, Greensboro, North Carolina 27402-6170, USA.
J Orthop Res. 2007 Aug;25(8):981-8. doi: 10.1002/jor.20397.
We examined the capabilities of the Vermont Knee Laxity Device (VKLD) in measuring varus (VR)-valgus (VL) and internal (INT)-external (EXT) rotational laxities by quantifying measurement consistency and absolute measurement error (N = 10). Based on the expected measurement error, we then examined side-to-side differences (N = 20). For all measures, the knee was flexed 20 degrees , the thigh securely fixed, and counterweights applied to the thigh and shank to create an initial zero shear and compressive load across the tibiofemoral joint. A 10-Nm torque was applied to the knee for VL and VR during non-weight-bearing, and a 5-Nm torque was applied for INT and EXT during non-weight-bearing and weight-bearing conditions. Position sensors measured angular displacements (deg). Except for INT during weight bearing, measurement consistency was good to excellent (range, 0.68-0.96), with absolute measurement errors generally less than 2 degrees for VR-VL and 3-4 degrees for INT-EXT. Although side-to-side differences were observed, they did not exceed absolute measurement errors. The VKLD yields reliable measures of VR-VL and INT-EXT laxities, with sufficient measurement precision to yield clinically relevant differences.
我们通过量化测量一致性和绝对测量误差（N = 10），研究了佛蒙特膝关节松弛度测量仪（VKLD）在测量内翻（VR）-外翻（VL）和内旋（INT）-外旋（EXT）松弛度方面的能力。基于预期的测量误差，我们随后研究了双侧差异（N = 20）。对于所有测量，膝关节屈曲20度，大腿牢固固定，并在大腿和小腿上施加配重，以在胫股关节上产生初始零剪切力和压缩力。在非负重状态下，对膝关节施加10 N·m的扭矩用于测量VL和VR，在非负重和负重状态下，对INT和EXT施加5 N·m的扭矩。位置传感器测量角位移（度）。除负重状态下的INT外，测量一致性良好至优秀（范围为0.68 - 0.96），VR - VL的绝对测量误差一般小于2度，INT - EXT的绝对测量误差为3 - 4度。尽管观察到了双侧差异，但它们未超过绝对测量误差。VKLD能够可靠地测量VR - VL和INT - EXT松弛度，具有足够的测量精度以产生临床相关差异。
