Hollow Notched K-Wires for Bone Drilling With Through-Tool Cooling

Area of Science:

• Orthopedic Surgery
• Biomaterials Engineering
• Surgical Innovation

Background:

• Kirschner wires (K-wires) are essential for bone fracture fixation.
• High heat generation during K-wire drilling can lead to bone thermal necrosis and osteonecrosis.
• Current methods lack sufficient control over temperature and debris removal.

Purpose of the Study:

• To develop and evaluate a novel hollow notched K-wire for improved bone drilling.
• To assess the impact of through-tool cooling on bone temperature, debris evacuation, and material removal rate.
• To compare the performance of the hollow notched K-wire against traditional solid K-wires.

Main Methods:

• Fabrication of a hollow notched K-wire using grinding and micro-milling on a stainless steel tube.
• Conducting bone drilling tests comparing hollow notched K-wires with solid K-wires.
• Implementing and evaluating through-tool compressed air and water cooling systems.

Main Results:

• Hollow notched K-wire drilling without cooling reduced peak bone temperature rise by 42%, thrust force by 59%, and torque by 62% compared to solid K-wires.
• Through-tool compressed air cooling further reduced peak bone temperature rise by 48% through enhanced convection and debris evacuation.
• Through-tool water cooling showed limited efficacy (26% reduction) due to bone debris blockage.

Conclusions:

• The hollow notched K-wire design effectively minimizes heat generation during bone drilling.
• Through-tool compressed air cooling with the hollow notched K-wire is a promising strategy to prevent bone thermal necrosis in orthopedic surgery.
• Further optimization of cooling systems may be needed for enhanced performance with water-based coolants.