Thangaraj Rajkumar, Jones Michael D, Theobald Peter
Trauma Biomechanics Research Group, Institute of Medical Engineering and Medical Physics, Cardiff University, The Parade, Cardiff, CF24 3AA, United Kingdom.
J Clin Orthop Trauma. 2018 Mar;9(Suppl 1):S19-S25. doi: 10.1016/j.jcot.2017.08.003. Epub 2017 Aug 31.
Surface tribological properties of a tendon in terms of coefficient of friction and lubrication mechanism are expected to change with the progression of surface tears which can affect the optimal function of the tendon. This study investigated whether coefficient of friction proportionally increases with the progression of a surface tear in a bovine tendon model.
The study was performed using a pin-on-glass tribometer and bovine tendon samples (n = 16) divided into 4 groups. One group of tendons had no surface tears and thus served as a control, whilst the other 3 groups comprised tendons with increasing severity of artificially-induced surface tears. The coefficient of friction and the lubrication mechanism of the four groups of samples were investigated, calculated and compared.
Statistical analysis showed significant change in coefficient of friction between the control group and the group with minimal tear (p < 0.05) while no difference noted between the groups of moderate to severe tear suggesting that the coefficient of friction increases initially with appearance of surface tears, though further progression to a significant tear do not cause a further increase in the frictional coefficient. There was no change in the lubrication mechanism between the groups.
This finding appears to contradict the speculation that the frictional coefficient continues to increase with an increase in surface tear severity. The finding has not been reported before and requires validation in future with testing in human tissue.
肌腱的表面摩擦学特性，如摩擦系数和润滑机制，预计会随着表面撕裂的进展而改变，这可能会影响肌腱的最佳功能。本研究调查了在牛肌腱模型中，摩擦系数是否会随着表面撕裂的进展而成比例增加。
本研究使用销-玻璃摩擦计和牛肌腱样本（n = 16），将其分为4组。一组肌腱没有表面撕裂，作为对照组，而其他3组肌腱的人工诱导表面撕裂严重程度逐渐增加。对四组样本的摩擦系数和润滑机制进行了研究、计算和比较。
统计分析表明，对照组与最小撕裂组之间的摩擦系数有显著变化（p < 0.05），而中度至重度撕裂组之间没有差异，这表明摩擦系数最初随着表面撕裂的出现而增加，尽管进一步发展为明显的撕裂并不会导致摩擦系数进一步增加。各组之间的润滑机制没有变化。
这一发现似乎与摩擦系数会随着表面撕裂严重程度的增加而持续增加的推测相矛盾。这一发现以前未曾报道过，未来需要在人体组织中进行测试以验证。
