title: Operative skill: quantifying surgeon's response to tissue properties.
abstract: BACKGROUND
  The aim of this study was to investigate how tissue characteristics influence psychomotor planning and performance during a suturing task. Our hypothesis was that participants would alter their technique based on tissue type with each subsequent stitch placed while suturing.
  
  
  METHODS
  Surgical attendings (n = 6), residents (n = 4), and medical students (n = 5) performed three interrupted sutures on different simulated materials as follows: foam (dense connective tissue), rubber balloons (artery), and tissue paper (friable tissue). An optical motion tracking system captured performance data from participants' bilateral hand movements. Path length and suture time were segmented by each individual stitch placed to investigate changes to psychomotor performance with subsequent stitch placements. Repeated measures analysis of variance was used to evaluate for main effects of stitch order on path length and suture time and interactions between stitch order, material, and experience.
  
  
  RESULTS
  When participants sutured the tissue paper, they changed their procedure time (F(4,44) = 5.14, P = 0.017) and path length (F(4,44) = 4.64, P = 0.003) in a linear fashion with the first stitch on the tissue paper having the longest procedure time and path length. Participants did not change their path lengths and procedure times when placing subsequent stitches in the foam (P = 0.910) and balloon materials (P = 0.769).
  
  
  CONCLUSIONS
  This study demonstrates quantifiable real-time adaptation by participants to material characteristics during a suturing task. Participants improved their motion-based performance with each subsequent stitch placement indicating changes in psychomotor planning or performance. This adaptation did not occur with the less difficult tasks. Motion capture technology is a promising method for investigating surgical performance and how surgeons adapt to operative complexity.
authors.affiliation: Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin. Electronic address: Ad'angelo@uwhealth.org.
authors.forename: Anne-Lise D
authors.initials: AL
authors.lastname: D'Angelo
authors.affiliation: Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin; Department of Kinesiology, School of Education, University of Wisconsin-Madison, Madison, Wisconsin.
authors.forename: Drew N
authors.initials: DN
authors.lastname: Rutherford
authors.affiliation: Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin.
authors.forename: Rebecca D
authors.initials: RD
authors.lastname: Ray
authors.affiliation: Department of Kinesiology, School of Education, University of Wisconsin-Madison, Madison, Wisconsin.
authors.forename: Andrea
authors.initials: A
authors.lastname: Mason
authors.affiliation: Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin.
authors.forename: Carla M
authors.initials: CM
authors.lastname: Pugh
mesh_terms: D002983:Clinical Competence; D006801:Humans; D061646:Operative Time; D011597:Psychomotor Performance; D013536:Suture Techniques
keywords: Education; Motion tracking; Performance; Simulation; Surgery; Suturing