Potential risk of thermal damage to cervical nerve roots by a high-speed drill

Abstract

Using the transverse processes of fresh porcine lumbar spines as an experimental model we evaluated the heat generated by a rotating burr of a high-speed drill in cutting the bone. The temperature at the drilled site reached 174 degrees C with a diamond burr and 77 degrees C with a steel burr. With water irrigation at a flow rate of 540 ml/hr an effective reduction in the temperature was achieved whereas irrigation with water at 180 ml/hr was much less effective. There was a significant negative correlation between the thickness of the residual bone and the temperature measured at its undersurface adjacent to the drilling site (p < 0.001). Our data suggest that tissues neighbouring the drilled bone, especially nerve roots, can be damaged by the heat generated from the tip of a high-speed drill. Nerve-root palsy, one of the most common complications of cervical spinal surgery, may be caused by thermal damage to nerve roots arising in this manner.

Is There a Role for an Ultrasonic Bone-Cutting Device in Adult Spinal Deformity: A Safety and Reproducibility Study

“…Spinal osteotomies have been associated with greater blood loss, durotomies, and neural deficits (2,3,13). Several different tools are used to perform osteotomies in adult spinal deformity surgery.…”

“…Conventional osteotomy tools including high-speed burs, and thread-wire saws and the use of osteotomes and a mallet in the presence midline bony defects rendering the spinal canal/cord vulnerable. Similarly, simply the vibration from the mallet striking the osteotome could pose unnecessary risk of incidental durotomies and /or worse injury to the midline neural elements and spinal cord (2,3,13).…”

“…However, due to the high technical nature of osteotomies such as facetectomy, Smith-Petersen osteotomy, and pedicle subtraction osteotomy, the use of traditional surgical tools including high-speed drills, rotating burs, and thread-wire saws, carry a risk of associated intraoperative complications such as durotomy, spinal cord or nerve root injury, visceral and vascular injury, and excessive blood loss (1)(2)(3). There is also an inherent inefficiency with the use of these surgical instruments (4).…”

Thermal model to investigate the temperature in bone grinding for skull base neurosurgery

“…Shin et al [7] has quantified that the highest temperature varied from 49 to 115°C under various cutting conditions in round bur bone milling. Hosono et al [8] suggested that tissues neighboring the drilled bone, especially nerve roots, can be damaged by the heat generated by bone drilling. Temperature up to 140°C was measured by Matthews et al [9] in drilling the human cortical bone.…”

Temperature prediction in high speed bone grinding using motor PWM signal

“…Although the temperature rise highly depends on tool types (e.g., drill, bur, K-wire), operating parameters (e.g., speed, force), and irrigation, suppressing the heat is always challenging due to the small range of temperature tolerance prior to the tissue damage, which occurs at 43°C [4]. For example, the temperature during drilling of bone could reach 90°C with high-speed twist drill [5], and over 50°C with milling tools [6–7].…”