Ishii Yoshinori, Noguchi Hideo, Matsuda Yoshikazu, Takeda Mitsuhiro, Walker Scott A, Komistek Richard D
Ishii Orthopaedic and Rehabilitation Clinic, 1089 Shimo-Oshi, Gyoda, Saitama 361-0037, Japan.
Knee. 2007 Aug;14(4):269-74. doi: 10.1016/j.knee.2007.04.002. Epub 2007 Jun 12.
This study determined the relationship between the in vivo kinematics and joint laxity of mobile-bearing knees.
Ten subjects who were judged clinically successful after a posterior-cruciate-ligament-retaining mobile-bearing total knee arthroplasty were analyzed under dynamic conditions using fluoroscopy, following a quantitative evaluation of coronal and sagittal laxity using Telos and KT-2000 arthrometers under static conditions.
Under static conditions, the anteroposterior laxity averaged 10.3 mm at 30 degrees of flexion, and 8.3 mm at 75 degrees . Abduction and adduction at full extension averaged 3.7 and 4.4 mm, respectively. Under dynamic conditions, 7/10 subjects demonstrated posterior femoral rollback of their lateral condyle moving from full extension to maximum knee flexion, and 8/10 experienced normal axial rotation patterns during deep knee bend activity. Furthermore, 7/10 subjects exhibited screw-home motion. 4/10 subjects experienced greater than 1.0 mm of condylar liftoff.
We could not predict a consistent relationship between the laxity and kinematics. The activity of the muscles and ligamentous tension under dynamic conditions might have a much greater effect on the kinematics with currently used prosthetic designs than the laxity of ligamentous structures under static conditions.
本研究确定了活动平台膝关节的体内运动学与关节松弛度之间的关系。
对10名在保留后交叉韧带的活动平台全膝关节置换术后临床判定成功的受试者，在静态条件下使用Telos和KT - 2000关节测量仪对冠状面和矢状面松弛度进行定量评估后，在动态条件下使用荧光透视法进行分析。
在静态条件下，屈膝30度时前后松弛度平均为10.3毫米，屈膝75度时为8.3毫米。完全伸展时外展和内收分别平均为3.7毫米和4.4毫米。在动态条件下，7/10的受试者在从完全伸展到最大屈膝过程中，其外侧髁出现股骨后滚，8/10的受试者在深屈膝活动中呈现正常的轴向旋转模式。此外，7/10的受试者表现出归位运动。4/10的受试者髁部抬起超过1.0毫米。
我们无法预测松弛度与运动学之间存在一致的关系。在动态条件下，肌肉活动和韧带张力对运动学的影响可能比静态条件下韧带结构的松弛度对目前使用的假体设计的影响大得多。
