Implant alignment and soft-tissue balancing are important factors in total knee arthroplasty (TKA). The purpose of this study was to design a mechanical balancing device, which measures deflections resulting from forces applied on each condyle to provide numerical data indicating the extent of ligament release needed, or angular changes in the bone cuts required to achieve a balanced knee. Two mechanical devices were designed and 3D printed, Pistol Grip and In-line. The Pistol Grip design consisted of a lever system that indicated the difference between lateral and medial forces with a single pointer. The In-line design allows for the quantification of the absolute force applied on each individual condyle. The two designs were evaluated on a test rig designed to model balance and imbalance conditions in the knee. For the Pistol Grip design maximum pointer deflection indicates a 2 mm change in elevation per condyle and/or a 3 degrees angular change of the condyles which can be corrected by adjusting the ligament lengths equivalent to 2 mm and/or by modifying the proximal or distal femur bone cut by 3 degrees. For the In-line design, maximum pointer deflection represented a 40 N load on the condyle. Our mechanical balancer designs were successful in providing information that can guide surgeons to accurately achieve balance through ligamentous releases and/or modification to bone cuts. The balancer designs are easy to use, do not require any electronics or software, and can be incorporated into the surgical procedure.

植入物对齐和软组织平衡是全膝关节置换术（TKA）的重要因素。这项研究的目的是设计一种机械平衡装置，该装置可测量施加在每个each突上的力引起的挠度，以提供数值数据，以指示所需的韧带释放程度或达到平衡膝盖所需的骨切角变化。设计了两种机械设备并进行了3D打印：手枪握把和In-line。手枪握把设计由一个杠杆系统组成，该杠杆系统可通过单个指针指示横向力和内侧力之间的差异。在线设计可量化施加在每个individual突上的绝对力。两种设计均在用于模拟膝盖平衡和不平衡状况的试验台上进行了评估。对于Pistol Grip设计，最大指针偏转指示每个con突的高度变化2 mm和/或the突的角度变化3度，可以通过将韧带长度调整为等于2 mm和/或通过修改近端或远端来校正股骨切开3度。对于串联设计，最大指针偏转表示the上的负载为40N。我们的机械平衡器设计成功地提供了信息，可以指导外科医生通过韧带的释放和/或修改骨切口来准确地达到平衡。平衡器设计易于使用，不需要任何电子设备或软件，并且可以整合到手术过程中。