title: A marker-less technique for measuring kinematics in the operating room.
abstract: Often in simulated settings, quantitative analysis of technical skill relies largely on specially tagged instruments or tracers on surgeons' hands. We investigated a novel, marker-less technique for evaluating technical skill during open operations and for differentiating tasks and surgeon experience level.
  
  
  
  We recorded the operative field via in-light camera for open operations. Sixteen cases yielded 138 video clips of suturing and tying tasks ≥5 seconds in duration. Video clips were categorized based on surgeon role (attending, resident) and task subtype (suturing tasks: body wall, bowel anastomosis, complex anastomosis; tying tasks: body wall, superficial tying, deep tying). We tracked a region of interest on the hand to generate kinematic data. Nested, multilevel modeling addressed the nonindependence of clips obtained from the same surgeon.
  
  
  
  Interaction effects for suturing tasks were seen between role and task categories for average speed (P = .04), standard deviation of speed (P = .05), and average acceleration (P = .03). There were significant differences across task categories for standard deviation of acceleration (P = .02). Significant differences for tying tasks across task categories were observed for maximum speed (P = .02); standard deviation of speed (P = .04); and average (P = .02), maximum (P < .01), and standard deviation (P = .03) of acceleration.
  
  
  
  We demonstrated the ability to detect kinematic differences in performance using marker-less tracking during open operative cases. Suturing task evaluation was most sensitive to differences in surgeon role and task category and may represent a scalable approach for providing quantitative feedback to surgeons about technical skill.
authors.affiliation: Wisconsin Surgical Outcomes Research Program, Department of Surgery, University of Wisconsin-Madison, Madison, WI.
authors.forename: Lane L
authors.initials: LL
authors.lastname: Frasier
authors.affiliation: Department of Industrial and Systems Engineering, University of Wisconsin-Madison, Madison, WI.
authors.forename: David P
authors.initials: DP
authors.lastname: Azari
authors.affiliation: Wisconsin Surgical Outcomes Research Program, Department of Surgery, University of Wisconsin-Madison, Madison, WI.
authors.forename: Yue
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Wisconsin Surgical Outcomes Research Program, Department of Surgery, University of Wisconsin-Madison, Madison, WI.
authors.forename: Sudha R
authors.initials: SR
authors.lastname: Pavuluri Quamme
authors.affiliation: Department of Industrial and Systems Engineering, University of Wisconsin-Madison, Madison, WI; Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Radwin
authors.affiliation: Wisconsin Surgical Outcomes Research Program, Department of Surgery, University of Wisconsin-Madison, Madison, WI.
authors.forename: Carla M
authors.initials: CM
authors.lastname: Pugh
authors.affiliation: Department of Industrial and Systems Engineering, University of Wisconsin-Madison, Madison, WI; Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI.
authors.forename: Thomas Y
authors.initials: TY
authors.lastname: Yen
authors.affiliation: Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, WI.
authors.forename: Chia-Hsiung
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Wisconsin Surgical Outcomes Research Program, Department of Surgery, University of Wisconsin-Madison, Madison, WI; Department of Industrial and Systems Engineering, University of Wisconsin-Madison, Madison, WI. Electronic address: greenberg@surgery.wisc.edu.
authors.forename: Caprice C
authors.initials: CC
authors.lastname: Greenberg
mesh_terms: D001696:Biomechanical Phenomena; D002983:Clinical Competence; D005260:Female; D006801:Humans; D007396:Internship and Residency / Q000379:methods; D008297:Male; D009873:Operating Rooms; D013514:Surgical Procedures, Operative / Q000193:education*; D013536:Suture Techniques / Q000193:education / Q000295:instrumentation; D013647:Task Performance and Analysis; D013996:Time and Motion Studies; D014741:Video Recording