Department for Orthopaedic Surgery, Unit of Experimental Orthopaedics, Medical University, 6020 Innsbruck, Austria.
Int Orthop. 2012 Nov;36(11):2249-53. doi: 10.1007/s00264-012-1642-2. Epub 2012 Aug 14.
Standard instrumentation tries to reproduce mechanical axes based on mechanical alignment (MA) guides. A kinematic alignment (KA) technique derives its plan from pre-operative MRI-measurements. This matched-pair cadaveric study compared the resulting postoperative alignments.
A prospective series of 12 torsos were acquired for a total of 24 limb specimens including intact pelvises, femoral heads, knees, and ankles.The cadavers received MRI scans to manufacture the kinematic alignment cutting guides. Two investigating surgeons performed total knee arthroplasties on randomly chosen sides using MA instruments. On the contralateral sides, KA cutting guides were used. A navigation system was used to measure final alignment.
The overall alignment showed no significant differences between the systems. In the MA group the differences between the planned and the final implantation regarding overall limb alignment ranged between 0.2° and 6.2°. In the KA group the differences between the planned and final implantation regarding overall limb alignment ranged between 0.3° and 9.1°. The differences of the deviation from plan for overall limb alignment showed no significant differences between the methods.
The different alignment strategies resulted in variations of the combinations of the three-dimensional component position on the femur and the tibia. However, the legs were aligned within comparable range for both chosen techniques.
标准器械试图根据机械对准（MA）指南来复制机械轴。运动对准（KA）技术从术前 MRI 测量中得出其计划。这项配对尸体研究比较了术后的对准结果。
对总共 24 个肢体标本（包括完整的骨盆、股骨头、膝盖和脚踝）的 12 个躯干进行了前瞻性系列研究。尸体接受 MRI 扫描以制造运动对准切割指南。两位研究医生使用 MA 器械对随机选择的侧位进行全膝关节置换术。在对侧，使用 KA 切割导向器。导航系统用于测量最终对准。
整体对准在两种系统之间没有显著差异。在 MA 组中，关于整体肢体对准的计划与最终植入之间的差异在 0.2°至 6.2°之间。在 KA 组中，关于整体肢体对准的计划与最终植入之间的差异在 0.3°至 9.1°之间。从整体肢体对准的计划偏差来看，两种方法之间没有显著差异。
不同的对准策略导致股骨和胫骨三个维度组件位置的组合发生变化。然而，对于两种选择的技术，腿部都在可比较的范围内对齐。
