Analysis of motion in laparoscopic instruments

In this study, a system is developed to assess the overall quality of movement, as applied to laparoscopic instruments. A laparoscopic forceps was fitted with a variable inductor as a key component of a Colpitts oscillator. Oscillator frequency is demodulated and digitized into a personal computer equipped with LabView, where trajectories are displayed, analyzed, and stored. In its first study, this system is used to assess velocity in one-dimensional control of instrument insertion depth. Test results indicate that no significant difference in instrument velocity was observed for dominant versus non-dominant hands or for insertion velocity from the first trial to the last. However, extraction of the instrument was seen to occur at significantly higher velocity than insertion, and extraction velocity actually increased over the duration of the trials.