Biomechanics Laboratory, Department of Kinesiology, The Pennsylvania State University, 29 Recreation Building, University Park, 16802, Pennsylvania; Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, Pennsylvania.
J Orthop Res. 2014 Jan;32(1):110-5. doi: 10.1002/jor.22477. Epub 2013 Sep 3.
We investigated the existence of a midtarsal joint locking mechanism using cadaveric simulations of normal gait. Previous descriptions of this phenomenon led us to hypothesize that non-coupled rotations of the calcaneocuboid and talonavicular (i.e., midtarsal) joints and cubonavicular and talocalcaneal joints occur at heel strike and during weight acceptance, after which joint rotations cease with all bone-to-bone orientations remaining constant during the latter portions of stance phase. Three-dimensional kinematics of the talus, calcaneus, cuboid, and navicular were recorded along with muscle and ground reaction forces. Finite helical axis parameters and joint angles of directly articulating bones were subsequently derived and examined. During weight acceptance, the midtarsal joints everted with obvious changes in the relative orientation of their helical axes. The relative non-parallel orientation of these axes then remained constant until late in stance when these joints inverted and dorsiflexed toward their original pre-stance orientation. The cubonavicular and talocalcaneal joints demonstrated complimentary behavior. Contrary to our hypothesis, the midtarsal joints remained compliant during foot flat and even more so during push-off, despite divergent joint axes. Joint rotations were present after weight acceptance, thereby challenging the concept that midtarsal joint locking produces a rigid lever during push-off. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:110-115, 2014.
我们通过正常步态的尸体模拟来研究中跗关节锁定机制的存在。之前对这一现象的描述使我们假设跟骨-骰骨和距下-跟舟（即中跗）关节以及跗舟-跟骨和距跟-跟骨关节的非耦合旋转发生在足跟接触和负重期，在此之后，所有骨头之间的方向在站立后期保持不变，关节旋转停止。记录了距骨、跟骨、骰骨和足舟骨的三维运动学以及肌肉和地面反作用力。随后推导出并检查了直接关节的骨骼的有限螺旋轴参数和关节角度。在负重期，中跗关节向外翻转，其螺旋轴的相对方向发生明显变化。然后，这些轴的相对非平行方向保持不变，直到站立后期，这些关节向内翻转并向原始站立前方向背屈。跗舟-跟骨和距跟-跟骨关节表现出互补的行为。与我们的假设相反，尽管关节轴发散，但中跗关节在足放平期甚至在蹬离期仍保持顺应性。在负重后存在关节旋转，这挑战了中跗关节锁定在蹬离期产生刚性杠杆的概念。©2013 矫形研究协会。由 Wiley Periodicals, Inc. 出版。J Orthop Res 32:110-115, 2014.
