Vibrating Needle Cutting Force

Needles are one of most commonly used medical devices, used to deliver drugs, biopsy tissue, draw blood, conduct brachytherapy cancer treatment and many other procedures. Maintaining a low insertion force of the needle is important to the success of these procedures. Utilizing vibratory cutting reduces the insertion force, thus improving the outcome of the procedure. This paper describes the experimental setup utilized to test the effectiveness of axial vibration in reducing the insertion force into porcine skin across a range of frequencies, amplitudes and needle sizes. Experiments showed the addition of the vibration was able to reduce the insertion force by up to 35%. The minimum insertion force occurred at lower maximum vibratory insertion speeds for larger diameter needles.