Comparison of k-wire insertion using oscillatory and unidirectional drilling modes under constant thrust force

Area of Science:

• Orthopedic surgery
• Biomedical engineering
• Surgical instrumentation

Background:

• Kirschner wire (K-wire) insertion generates heat, risking thermal osteonecrosis and infection.
• Quantitative data on heat generation differences between unidirectional and oscillatory drilling modes is lacking.
• Optimal thrust force for K-wire insertion under different drilling modes remains unknown.

Purpose of the Study:

• To investigate the impact of drilling modes (unidirectional vs. oscillatory) and thrust force levels on bone drilling outcomes.
• To quantitatively compare heat generation and other process parameters between drilling modes.
• To determine optimal thrust force levels for minimizing bone damage during K-wire insertion.

Main Methods:

• Controlled machine-based experiments using constant thrust force for K-wire insertion.
• Monitoring and quantitative comparison of key process parameters, including thermal energy, peak temperature, torque, and drilling depth.
• Statistical analysis of collected data.

Main Results:

• Oscillatory mode consumed 2.6x more electricity but generated 53% less thermal energy and 23% lower peak temperature than unidirectional mode.
• Oscillatory drilling resulted in 18% higher peak torque and 23% shallower drilling depth.
• Heat generation was primarily influenced by torque and rotational power in both modes.

Conclusions:

• Oscillatory drilling is superior for minimizing bone thermal damage, while unidirectional drilling offers better torque control and drilling depth.
• The choice of drilling mode should align with surgical priorities: minimizing temperature or controlling torque and depth.
• Optimal thrust force strategies differ: moderate force for unidirectional drilling to balance feed and debris, and minimal force for oscillatory drilling to maintain engagement.