Heat caused by drilling cortical bone: Temperature measuredin vivoin patients and animals

Abstract

In vivo temperature measurements were performed at drilling in the femoral cortex of the rabbit, dog and man. In the clinical study the bone temperature was measured at fixation of a Richards plate to stabilize a pertrochanteric fracture. With a drill speed of around 20 000 rpm and saline cooling, temperatures of 40 degrees C in rabbits, 56 degrees C in dogs and 89 degrees C in patients were recorded at a distance of 0.5 mm from the periphery of the drill hole. The difference in temperature between the animal and clinical studies was mainly attributed to the difference in cortical thickness between the species. When drilling straight through the canine femur from the lateral to the medial side, a 9 degrees C higher temperature was measured in the remote, medial cortex compared to that recorded in the lateral cortex. This difference arose because it is difficult for the cooling agent to reach the medial cortex. The results of the present study indicate that temperatures measured in animal experiments are not applicable to the clinical situation where very high temperatures may arise on drilling in cortical bone, even if saline cooling is used.

Drilling of Bone: Practicality, Limitations and Complications Associated with Surgical Drill-Bits

“…They attributed this result to the difference in mean cortical thickness between the cadaveric (3 to 5mm) and bovine (7 to 9 mm) samples. Eriksson et al (Eriksson, Albrektsson et al 1984a) measured in vivo temperature elevations during drilling of rabbit, dog and human tibiae, encountering temperatures of 40˚, 56˚ and 89˚, respectively, under similar conditions. The differences in this study were also attributed to the difference in cortical thickness between species.…”

Surgical preparation of bone–scaffold interface is critical for bone regeneration inside tissue engineering scaffold

“…Although we have used a higher drilling speed, this difference would not result in significant temperature elevation, as was previously demonstrated. [17][18][19][20][21][22][23] The duration of drilling in our experiment was <5 s which is shorter than the 30 s critical exposure reported by Lundskog. 22 Moreover, the thickness of rat cortical bone at distal femoral sites (1 mm) is much thinner than the thickness of human cortical bone.…”

“…15 However, the focus of all these studies has been on the corresponding increase in temperature and thermal damage due to drilling the cortical bone. [16][17][18][19] The effect of drilling on trabecular bone was not studied, perhaps due to a priori assumption that temperature increase is less significant and hence less crucial in this less dense part of the bone. Indeed, an important effect of drilling trabecular bone might not be the increase in temperature, but the damage to the structure of adjacent trabeculae, which may have serious biological consequences.…”

Temperature control with internally applied cooling in solid material drilling: an experimental, biomechanical study

“…Earlier investigations have shown a reduction in drilling temperature by external cooling and high feed forces [13][14][15][16][17]. Another study indicated an increase in drilling temperature when using a blunt drill.…”