Kinematic analysis in oculoplastic reconstructive surgery: measuring manual control and fluidity of movement.

OBJECTIVE: To evaluate higher-order kinematic analysis, a technique not previously applied to surgical skills assessment, as a tool for elucidating patterns of movement.

METHODS: An observational cohort study of 27 subjects, divided into 3 equal groups based on surgical experience consisting of novice (performed <5 prior procedures), intermediate (performed 5-100 prior procedures), and expert (performed >100 prior procedures) subjects. The subjects placed a deep 3-1-1 suture onto a shielded hook on a standardized surgical skills practice board. Detailed 3-dimensional motion data were obtained using a motion capture system. Two novel parameters were used to analyze movement patterns: the frequency distribution (cumulative histogram), describing the distribution of movement sizes used, and the probability density function (normalization of frequency distribution data), evaluating the distribution of motion against the magnitude of movement. The α risk for statistical significance was set at .05.

RESULTS: We found significant differences among the 3 groups for frequency distribution (P = .02; Kruskal-Wallis test) and probability density function (P = .03).

CONCLUSIONS: These 2 indices, derived from kinematic analysis, appear to distinguish between groups of test subjects with known differences in surgical experience. The evaluation of higher-order motion patterns appears to be of value in the objective evaluation of surgical skills. This method for assessment of manual skills is likely to provide a better guide as to which patterns of movement have the greatest efficiency for specific tasks.