Thomas AC, Hayes GM, Demetriou JL. Comparison of Veterinary Student Ability to Learn 1-Handed and 2-Handed Techniques for Surgical Knot Tying. Vet Surg. 2015 Aug;44(6):798-802

PMID: 25727913


Objective: To determine which type of surgical hand-tie trainee surgeons learn most readily in a laboratory setting, using a combination of audiovisual demonstration and one-on-one teaching.

Study design: Randomized controlled learning trial.

Sample population: Year 4 veterinary students in their 1st year of clinical training (n = 58).

Methods: Veterinary students entering clinical rotations were randomly allocated to 2 learning groups: 1-handed (28 students) or 2-handed (30 students) surgical ties. Knot tying technique was taught followed by three 15-minute practice sessions with student progress recorded by filming each student tying a square knot (2 throws). All 3 knot tying attempts were scored for technique and knot formation. Data on potential confounding factors between groups, including age and gender, were recorded.

Results: There were no significant differences between group scores for each attempt (1st attempt P = .5; 2nd P = .2; 3rd P = .19). Initially, scores indicated more rapid learning in the 1-handed group but fewer individuals achieved a perfect technique and knot after 60 minutes of learning (29/30 for 2-handed; 24/28 for 1-handed group). The 1-handed group was the most error-prone (after 45 minutes P < .01; after 60 min P < .01).

Conclusions: Over 95% of students in the 2-handed group performed the technique and knot perfectly after 60 minutes learning time; were significantly less error-prone and fewer students continued to make corrected errors after 60 minutes. This evidence indicates that the 2-handed technique allows students to achieve success in a manageable teaching time.