Attainment and retention of force moderation following laparoscopic resection training with visual force feedback.

BACKGROUND: Laparoscopic training with visual force feedback can lead to immediate improvements in force moderation. However, the long-term retention of this kind of learning and its potential decay are yet unclear. METHODS: A laparoscopic resection task and force sensing apparatus were designed to assess the benefits of visual force feedback training. Twenty-two male university students with no previous experience in laparoscopy underwent relevant FLS proficiency training. Participants were randomly assigned to either a control or treatment group. Both groups trained on the task for 2 weeks as follows: initial baseline, sixteen training trials, and post-test immediately after. The treatment group had visual force feedback during training, whereas the control group did not. Participants then performed four weekly test trials to assess long-term retention of training. Outcomes recorded were maximum pulling and pushing forces, completion time, and rated task difficulty. RESULTS: Extreme maximum pulling force values were tapered throughout both the training and retention periods. Average maximum pushing forces were significantly lowered towards the end of training and during retention period. No significant decay of applied force learning was found during the 4-week retention period. Completion time and rated task difficulty were higher during training, but results indicate that the difference eventually fades during the retention period. Significant differences in aptitude across participants were found. CONCLUSIONS: Visual force feedback training improves on certain aspects of force moderation in a laparoscopic resection task. Results suggest that with enough training there is no significant decay of learning within the first month of the retention period. It is essential to account for differences in aptitude between individuals in this type of longitudinal research. This study shows how an inexpensive force measuring system can be used with an FLS Trainer System after some retrofitting. Surgical instructors can develop their own tasks and adjust force feedback levels accordingly.

Visual force feedback improves knot-tying security.

BACKGROUND: 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. METHOD: 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. RESULTS: 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. CONCLUSION: 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.