2019 AMI Online Salon

PS Knee Exam: Forces and Torques of the Pivot Shift Exam

Project Details

  • Entrant Name: Virginia Ferrante-Iqbal
  • Membership Type: Professional Submission
  • Address: Chicago, IL
  • Client: Carl W Imhauser, Hamidreza Jahandar, Biomechanics, The Hospital for Special Surgery
  • Medium/software used: Adobe Illustrator
  • Final presentation format: Journal Article- American Journal of Sports Medicine
  • Primary Audience: Orthopedic Surgeons

Project Description

Show the experimental setup to measure the forces and torques of the Pivot Shift (PS) knee exam, when diagnosing ACL injury. To depict: 1) cadaver leg with pelvis attached to a six-axis force-torque sensor, pins inserted in pelvis, bars, nuts, and bolts, no skeleton. 2) proper position of surgeon holding leg, poised to do the PS. Do not show motion. 3) correct positioning of reflective markers on tibia, femur, and pelvis to be tracked by motion sensor cameras. The PS is used commonly by orthopedic surgeons but it is difficult to know the exact force and motion required to do this exam. The purpose of this study was to quantify the loads applied to the knee during a PS exam by experienced sports surgeons; to determine if these forces varied among surgeons; to assess whether variations in the magnitude of applied forces and torques were related to the magnitude of tibial translation during the reduction phase of the PS.