Visual force feedback improves knot-tying security

Residents in surgical specialties suture multiple wounds in their daily routine and are expected to be able to perform simple sutures without supervision of experienced surgeons. To learn basic suture skills such as needle insertion and knot tying, applying an appropriate magnitude of force in the desired direction is essential. To investigate if training with real-time visual force feedback improves the suture skills of novices, a study was conducted using a training platform that measures all forces exerted on a skin pad, i.e., the ForceTRAP.

Two groups of novices were trained on this training platform during a suture task. One group (nov-c) received no visual force feedback during training, whereas the test group (nov-t) trained with visual feedback. The posttest and follow-up test were performed without visual force feedback.

A significant difference in reaction force, (nov-c: mean 2.47N standard deviation [SD] ± 0.62, nov-t: mean 1.79N SD ± 0.37), suture strength (nov-c: median 25N interquartile range (IQR) 15, nov-t: median 50N interquartile range 25), and task time (nov-c: mean 109s SD ± 22, nov-t: mean 134s SD ± 31) was found between the control and training group of the posttest.

Participants that are trained with visual force feedback produce the most secure knots in the posttest and their suturing results in lower applied forces. Therefore, the results of this study indicate that visual force feedback supports students while learning to insert the needle smoothly, to effectively align the suture threads and to balance the force between instruments during knot tying. However, for long-term learning effects, probably more than 1 training session is required.