An Assessment of Fine Surgical KnotTying

Abstract

Objective: Operating room simulation exercises have been well established as an effective means of improving confidence, task engagement, and learning retention among surgical residents. We have established a cost-effective model and scoring system assessing resident skills to tie secure surgical knots with minimal tension.

Design: A circular grid divided into 18 segments was placed underlying an aluminum can. Trainees tie 20 surgical square knots scored for time and total knot length. Movement of the can outside the grid served as a scoring penalty. Recorded were time, length of the 20 knots, and number of segments exposed at exercise end. A score was developed to identify a progression of skills with PGY level. All outcomes were compared between classes using ANOVA.

Setting: Brown University/Rhode Island Hospital Department of Surgery.

Participants: Surgical residents (PGY1-PGY5) and participating attending surgeons employed by Rhode Island Hospital.

Results: Knot length and exposed segments showed trends of improved scores with ascending PGY level. Only average time attained statistical significance. Overall scores improved with PGY level: Composite scores significantly improved when comparing PGY1 to PGY3, PGY5, and Attending surgeons (p = 0.016, 0.011, and 0.011, respectively). Time significantly improved when comparing PGY1 to PGY3 and Attending surgeons (77vs. 50 and 47 seconds, p = 0.019 and 0.022 respectively). Composite scores were not significantly different above PGY3.

Conclusions: A low fidelity, high impact knot tying model has been developed to assess the ability to securely tie surgical knots while minimizing tension, with linear increases in scores that appear to plateau at the PGY3 level.

Keywords: Medical Knowledge; Practice-Based Learning and Improvement; Surgical education; Systems-Based Practice; knot tying; learning techniques; resident education; surgery simulation.