Westblad Pär, Hashimoto Takeshi, Winson Ian, Lundberg Arne, Arndt Anton
Karolinska Institute, Dept Orthopedic Surgery, Huddinge University Hospital, Sweden.
Foot Ankle Int. 2002 Sep;23(9):856-63. doi: 10.1177/107110070202300914.
Bones of the ankle-joint complex are difficult to represent with superficial markers and an invasive approach is required to quantify skin movement artifact. Three-dimensional coordinates during gait were first calculated from sets of three superficial markers located on both the lower leg and heel. Intracortical pins equipped with external marker arrays were subsequently inserted in the tibia, talus and calcaneus for further trials. Tibiocalcaneal and talocalcaneal joint helical axis component rotations were calculated. Intersubject motion patterns were comparable. Root mean square (RMS) differences were chosen to describe discrepancies between temporal intracortical pin and superficial marker curves. Results for the tibiocalcaneal rotations inversion/eversion, plantarflexion/ dorsiflexion and abduction/adduction were 2.5 degrees, 1.7 degrees and 2.8 degrees respectively. Inversion/eversion about the talocalcaneal joint showed an RMS difference of 2.1 degrees. A systematic over- or underestimation of superficial relative to bone-anchored markers could not be determined.
踝关节复合体的骨骼很难用体表标记来呈现，需要采用侵入性方法来量化皮肤运动伪影。首先根据位于小腿和足跟的三组体表标记计算步态期间的三维坐标。随后在胫骨、距骨和跟骨中插入配备有外部标记阵列的皮质内针进行进一步试验。计算了胫跟关节和距跟关节螺旋轴分量旋转。受试者间的运动模式具有可比性。选择均方根（RMS）差异来描述皮质内针和体表标记曲线在时间上的差异。胫跟关节旋转内翻/外翻、跖屈/背屈和外展/内收的结果分别为2.5度、1.7度和2.8度。距跟关节的内翻/外翻均方根差异为2.1度。无法确定相对于骨锚定标记，体表标记存在系统性高估或低估的情况。
