Unsworth A, Dowson D, Wright V
Ann Rheum Dis. 1975 Aug;34(4):277-85. doi: 10.1136/ard.34.4.277.
Theoretical consideration has been given to the use of pendulum machines which are used to examine the frictional properties of human joints by incorporating them as fulcra. As a result, a new type of pendulum machine has been built which incorporates the facility to apply sudden loads to the joint on starting the swinging motion, and also the ability to measure directly the frictional torque experienced by the joint. The results obtained from natural hip joints indicate the presence of squeeze film lubrication under conditions of sudden loading of a joint. In addition, a self-generated fluid film process was observed at low loads while at higher loads boundary lubrication appeared to be important. These results have been used to describe the lubrication regimens occurring in a normal activity such as walking. A single experiment carried out on a hip from a patient suffering from severe rheumatoid arthritis has also been reported and the frictional resistance was seen to be increased fifteenfold compared to a normal hip.
已对摆锤式机器的使用进行了理论考量，这种机器通过将人体关节作为支点来检查其摩擦特性。因此，制造出了一种新型摆锤式机器，它具备在摆动运动开始时对关节施加突然载荷的功能，以及直接测量关节所受摩擦扭矩的能力。从天然髋关节获得的结果表明，在关节突然加载的情况下存在挤压膜润滑。此外，在低载荷时观察到了自生成流体膜过程，而在高载荷时边界润滑似乎很重要。这些结果已被用于描述正常活动（如行走）中发生的润滑方式。还报道了对一名患有严重类风湿性关节炎患者的髋关节进行的单次实验，结果发现其摩擦阻力比正常髋关节增加了15倍。
