Buttermann G R, Schendel M J, Kahmann R D, Lewis J L, Bradford D S
Department of Orthopaedic Surgery, University of Minnesota, Minneapolis.
Spine (Phila Pa 1976). 1992 Jan;17(1):81-92. doi: 10.1097/00007632-199201000-00013.
This study describes a technique to measure in vivo loads and the resultant load-contact locations in the facet joint of the canine lumbar spine. The technique is a modification of a previously described in vitro method that used calibrated surface strains of the lateral aspect of the right L3 cranial articular process. In the present study, strains were measured during various in vivo static and dynamic activities 3 days after strain gage implantation. The in vivo recording technique and its errors, which depend on the location of the applied facet loads, is described. The results of applying the technique to five dogs gave the following results. Relative resultant contact load locations on the facet tended to be in the central and caudal portion of the facet in extension activities, central and cranial in standing, and cranial and ventral in flexion or right-turning activities. Right-turning contact locations were ventral and cranial to left-turning locations. Resultant load locations at peak loading during walking were in the central region of the facet, whereas resultant load locations at minimum loading during walking were relatively craniad. This resultant load-contact location during a walk gait cycle typically migrated in an arc with a displacement of 4 mm from minimum to maximum loading. Static tests resulted in a range of facet loads of 0 N in flexion and lying to 185 N for two-legged standing erect, and stand resulted in facet loads of 26 +/- 15 N (mean +/- standard deviation [SD]). Dynamic tests resulted in peak facet loads ranging from 55 N while walking erect to 170 N for climbing up stairs. Maximum walk facet loads were 107 +/- 27 N. The technique is applicable to in vivo studies of a canine facet joint osteoarthritis model and may be useful for establishing an understanding of the biomechanics of low-back pain.
本研究描述了一种测量犬腰椎小关节体内负荷及由此产生的负荷接触位置的技术。该技术是对先前描述的体外方法的改进，后者使用了右侧L3颅侧关节突外侧的校准表面应变。在本研究中，在植入应变片3天后的各种体内静态和动态活动期间测量应变。描述了体内记录技术及其误差，这些误差取决于所施加的小关节负荷的位置。将该技术应用于五只犬的结果如下。在伸展活动中，小关节上相对的合力接触负荷位置倾向于位于小关节的中央和尾部，站立时位于中央和头部，屈曲或右转活动时位于头部和腹侧。右转接触位置在腹侧且比左转位置更靠近头部。行走过程中峰值负荷时的合力负荷位置位于小关节的中央区域，而行走过程中最小负荷时的合力负荷位置相对更靠近头部。步行步态周期中的这种合力负荷接触位置通常以弧形移动，从最小负荷到最大负荷的位移为4毫米。静态测试导致小关节负荷范围为：屈曲和躺卧时为0牛，双腿直立站立时为185牛，站立时小关节负荷为26±15牛（平均值±标准差[SD]）。动态测试导致小关节峰值负荷范围为：直立行走时为55牛，爬楼梯时为170牛。最大步行小关节负荷为107±27牛。该技术适用于犬小关节骨关节炎模型的体内研究，可能有助于建立对下腰痛生物力学的理解。
