Reducing Degrees of Freedom in Surgical Suturing: Implications for Minimally Invasive Device Development-A Prospective Experimental Study

Surg Laparosc Endosc Percutan Tech. 2021 May 21;31(4):421-427. doi: 10.1097/SLE.0000000000000961.

Abstract

Open surgery allows the use of all 6 degrees of freedom (DOF; x-y-z and roll-pitch-yaw), whereas laparoscopy requires working under limitation to 4 axes. We present a prospective experimental study evaluating translational and rotational DOF restriction in surgical suturing tasks. An experimental platform included a kinematic structure that limited the maneuverability of the surgical instruments. The subjects (n=20) worked in a randomized order using (1) 6DOF, (2) 4DOF with 3 translational and 1 rotational DOF (4TRANS), and (3) 4DOF with 1 translational and 3 rotational DOF (4ROT). The time required to perform each task was recorded. Suturing and knot tying were significantly faster under 6DOF compared with 4ROT (both P<0.001) and 4TRANS (both P<0.001). Assessment of subjective difficulty and impairment showed most favorable results for 6DOF. The advantage of rotational compared with translational DOF should be considered in the development of future surgical devices.

MeSH terms

  • Humans
  • Laparoscopy*
  • Prospective Studies
  • Suture Techniques
  • Sutures*