Faculty of Engineering, Islamic Azad University-Tehran North Branch, Sadoughi Blvd, Hakimiyeh Wayout, Shahid Babaei Highway, Tehran, 1651153311, Iran.
Phys Eng Sci Med. 2020 Sep;43(3):959-972. doi: 10.1007/s13246-020-00892-1. Epub 2020 Jul 6.
Heat generation during bone drilling operations is a serious challenge for the internal fixation surgery of bone fracture. Indeed, the heat generated at the drilling site causes complications including local temperature rise, thermal necrosis, irreversible damages to the bone tissue, and possible failure of orthopedic surgery. High-speed machining is an advanced method which has achieved remarkable results in some cases of reducing the temperature rise of the tool or workpiece. The present research examines high-speed drilling (HSD) of the bone using theoretical (based on Orthogonal Cutting theory and High-Speed Cutting model) and experimental (based on infrared thermography) approaches. The thrust force and temperature changes of the bone and drill bit have been measured at different rotational speeds. The drilling tests have been performed under a constant feed rate of 100 mm min, hole depth of 8 mm, and 18 rotational speeds of 1000-18,000 r min (with 1000 r min intervals) on a bovine femur. The results indicated that application of high rotational speeds in most cases caused increased temperature rise of the bone; only the rotational speed of 7000 r min (which is associated with dramatic force reduction) and speed of 11,000 r min (which is associated with alteration of the chip formation mechanism and its nature) resulted in the minimum extent of temperature rise in the bone. It was also observed that the High-Speed Cutting model was able to correctly estimate the threshold of high-speed machining range for the bone (5000 r min) and was also valid for the bone drilling operation.
在骨钻手术过程中产生的热量是骨内固定手术的一个严重挑战。事实上，在钻孔部位产生的热量会导致各种并发症，包括局部温度升高、热坏死、对骨组织的不可逆转损伤以及可能导致骨科手术失败。高速加工是一种先进的方法，在某些情况下已经取得了显著的效果，可以降低工具或工件的温升。本研究采用理论（基于正交切削理论和高速切削模型）和实验（基于红外热成像）方法研究了骨的高速钻削（HSD）。在不同转速下测量了骨和钻头的推力和温度变化。在恒进给速度为 100mm/min、孔深为 8mm、转速为 1000-18000r/min（间隔 1000r/min）的条件下，在牛股骨上进行了钻孔试验。结果表明，在大多数情况下，应用高转速会导致骨温升增加；只有转速为 7000r/min（与力的急剧下降有关）和 11000r/min（与切屑形成机制及其性质的改变有关）会导致骨温升最小。还观察到高速切削模型能够正确估计骨的高速加工范围的阈值（5000r/min），并且对骨钻削操作也有效。
