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The objective of the present work is to develop a haptic system that will permit the demonstration of a proof of concept for the simulation of haptic effects typical of pediatric spine surgery. The first phase of this project focused on the development of a custom haptic system, and was followed by evaluation with experienced orthopedic surgeons. Initial findings demonstrate promise of this approach for further development into an advanced haptic system.

Current theories of skill learning suggest that novices learn optimally in a simplified environment. This information can be incorporated in simulator designs. Our purpose was to assess whether basic visuospatial training is beneficial for performance on an arthroscopy model. One group of trainees practiced three visuomotor tasks while the other group was not given this opportunity. Both groups then performed three different surgical tasks on a simulated arthroscopy model. Practice with the visuomotor tasks enhanced performance on two of the tasks on the arthroscopy model. The basic navigational skills learned through practice transferred to the performance of arthroscopic surgery tasks and these skills should be included in the design of a comprehensive arthroscopy simulator.

This study explored the activities of trainees learning technical skills using an educational networking tool with and without expert facilitation. Medical students (participants) were video-recorded practicing suturing and knot tying techniques and the resulting videos were uploaded to an educational networking site. Participants were then divided into two groups (one group containing an expert facilitator while the other group did not) and encouraged to comment on the videos within their group. We monitored the number of logins and comments posted and all participants completed an exit survey. There were no differences between the activities the two groups (p = 0.387). We conclude that the presence of an expert within collaborative Internet environments in not necessary to promote interactivity amongst the learners.

This pilot study explored the use of tensiometry as a measure of retention of knot tying skills. Medical students learned a one-handed square knot tying technique. Their final performances were video recorded and these videos were uploaded on to a website. Students were divided into two groups: an observational learning group that had access to videos before a retention test, and a control group that did not. After a two-week retention period, all students came back and performed one more trial to test the amount of retention of the skill. Tensiometry was used to measure strengths of the knots before and after the retention period. The scores showed no significant difference between the groups (pgt;0.308) or tests (pgt;0.737). We interpret the results to suggest that tensiometry is not sensitive enough to detect degradation in the performance of fundamental clinical skills as they are forgotten after being taught.

The cognitive demands of endoscopic surgery are amplified when rotations of the displayed surgical field cause discrepancies between intended and actual movements. While Visuo-Motor Misalignment (VMM) often impairs surgical technical performance, motor learning literature has demonstrated adaptation acquisition with practice. It is unknown whether these findings can be generalized to complex tasks of surgery. Two experiments investigated VMM adaptation processes within a laparoscopic context. The first examined the effects of practice and angle of visual rotation while the second investigated if, and how, the Contextual Interference Effect facilitates VMM adaptations. Laparoscopic performance was positively affected with smaller angles of visual rotation (p.001) and increasing trials (p.001). While not significant, performance was better after blocked versus random practice. In order to facilitate VMM adaptation acquisition, it is recommended that future simulated trainers incorporate the capacity for practice under visual rotation with flexibility in practice schedule.

We hypothesized that simulation based practice will results in skill improvement on trocar insertion task. Novices, junior trainees and surgeons inserted a trocar into a simulated abdomen. The depth of penetration (plunge) was the similar for novice and junior trainees (p=.98), and exceeded that observed for practicing surgeons (p.05). Trocar insertion may be an important variable to consider for surgical skill training. To date, no virtual reality (VR) trainers allow for practice of this skill. We will present a prototype of a VR trainer designed.

Haptics, namely the sense of touch, has been playing an important role in medical simulation. However, most medical practitioners, who are best suited to create the training environments, do not have the engineering expertise necessary for programming a haptic environment. We propose a user-friendly interface that allows surgeons to arbitrarily select regions on a 3D model of an organ, similar to "painting-by-numbers", and tune the haptic properties of each region in an intuitive way. The selected region and tuned haptic properties are recorded in a lookup table in real-time. The proposed user interface is assessed by comparing the haptic effects of a tumor on a virtual liver created by a number of surgeons.

The purpose of this study was to investigate the ability to discriminate friction during surface exploration using a finger and surgical instrument under normal vision and when vision was absent. Participants explored surfaces with either with the finger or with an instrument and rated the slipperiness. Results showed that the explorations with the instrument were estimated to be more slippery and less sensitive than those for the finger. There were no effects for visual condition. This study showed that novices who use instruments to make estimations of tissue slipperiness require practice and training in order to adequately perceive friction. Novices' reduced ability to perceive friction with instruments should be integrated into simulator design.

Laparoscopic surgery requires new methods of technical competency evaluation, as well as training. The first purpose was to assess the differences in motion characteristics between the tip of the instrument and the wrist. The second purpose was to determine whether similar control strategies are used to move instruments in virtual reality and bench model environments. Surgically naive participants were required to tap a laparoscopic instrument between two targets that differed in size and separation distance. Large amplitude movements were controlled with the movements of the wrist and small amplitude with the wrist and the fingers (p.001). Participants utilized the flexibility of the skin of the laparoscopic trainer to facilitate their movements. These results suggest that monitoring the motions of the instrument tip is a more precise indication of its motions than are motions of the wrist when movements of small amplitudes are produced. Moreover, in order to increase fidelity, VR trainers should simulate the flexibility of the real structures around the insertion of the instrument.