Benefits of using the "Micro-Clock" to evaluate the acquisition and maintenance of microsurgery skills.

This study was done using an educational tool called the "Micro-Clock", which was inspired by Chan's "round-the-clock" training model. The Micro-Clock consisted of a surgical sponge on which 12 sewing needles were configured in the shape of a clock. The subjects were asked to thread a small suture through the eyelets as quickly as possible. Steadiness and instrument manipulation were evaluated during each trial and graded from 1 to 3. The execution time was measured in seconds. Fifteen instructors did the Micro-Clock test once in order to validate this tool's ability to assess the skills of qualified microsurgeons. Next, nine students, who were enrolled in a microsurgery diploma program, did the test nine times during the program to measure their progression and to evaluate their mastery and execution speed. There was no significant differences among the three instructor sub-groups (residents, assistants and senior surgeons) in their steadiness, instrument manipulation and execution time. When the students performed the Micro-Clock test, there was a significant improvement in movement fluidity as well as the execution time between the first and ninth test. Nevertheless, the execution time did not improve further after the fourth test. The Micro-Clock is a useful and reliable tool for teaching microsurgery skills and testing the maintenance of skills in qualified microsurgeons.