Surgeons as Educators A Guide for Academic Development and Teaching Excellence

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plots look remarkably different, in that the expert surgeon has condensed and con-
cise movements, whereas the novice generates an amorphous heap of unnecessary
motion [ 29 ]. The trakSTAR system costs around $4000 and is easily attached to da
Vinci tools or other laparoscopic instruments.
Using the FLS block transfer and intracorporeal suturing tasks as well as a novel
ring tower exercise, time (s), path length (cm), and economy of motion (cm/s) were
tested using trakSTAR technology. In all areas the experienced surgeon scored bet-
ter than the novices, and the generated position plots demonstrated why. Graphs
plotting instrument tip paths in Fig. 5.23a, b illustrate how the expert surgeon can
distinguish left- and right-hand motions to their respective sides of the given task, as
well as minimizing excessive or unnecessary motions. The expert was shown to
have clean, distinct motion depictions, while novices have a cloud of extraneous
movement. Experts also utilize less three-dimensional space than the novices are
able to, marking greater precision with their instruments [ 29 ].
Other trackers that have been utilized for laparoscopic techniques include
AURORA from Northern Digital Inc., Ontario, Canada, which functions with an
electromagnetic field like trakSTAR but is a smaller system, and TrENDO, from
Delft University of Technology, Delft, the Netherlands, which is only an optical
tracker. TrENDO is a two-axis three-sensor gimbal device [ 30 ]. The instrument is
inserted through the sensors, which can then measure four degrees of freedom.
Information about the motions is transferred across 100  Hz. The setup is bulkier
than other options and is integrated into the box trainer itself.
Data from tracker systems such as these is useful but requires some vector analy-
sis for the information to have any meaning. They also can only be used on a box
trainer, never applied to a clinical setting, severely limiting when assessment can
occur. Trackers also fail to grade the quality of the surgeon’s work. Things like
incorrect knots, broken suture, missed cuts, and instrument collisions must either be
counted by an observer or forsaken.

abNOVICE EXPERIENCED

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Fig. 5.23 3D Cartesian coordinates of novice (a) and expert (b) robotic tool tips during FLS block
transfer task plotted from trakSTAR system [ 29 ]

E.I. George et al.