Frequently Asked Questions about Clinical Gait Analysis

Practical difficulties

  • getting the patient to walk 'normally'
  • hitting the force-platform
  • effect of walkway carpeting
  • the special challenges of analysing children
  • effect of walking aids
  • effect of arm-swing on gait

    Identifying segment locations

  • choice of motion analysis technique
  • 2D vs. 3D
  • marker identification
  • marker-less tracking
  • marker-skin motion

    Smoothing & differentiation

  • interpolation of missing markers
  • filtering vs. curve-fitting
  • choice of cut-off frequency
  • accuracy of differentiation


  • Is standardization needed?
  • gender effects
  • Body mass & Stature or limb-length
  • Time
  • Velocity, cadence & stride length
  • Variability in joint moment & power patterns


  • Joint centre estimation
  • Hip-joint centre estimation
  • Knee anthropometry
  • measurement vs. regression estimation
  • Accuracy requirements
  • Prostheses

    Understanding gait

  • origin of ground reaction forces
  • passive vs. active dynamics
  • interpretation of joint moments and powers
  • segment powers
  • how many steps do we take in a year?
  • muscle length-tension relationship & Hill model

    And frequent administrative questions...

  • how much to charge for a gait analysis?
  • how to start a gait-lab?

    Back to Clinical Gait Analysis home page

    Maintained by Dr Chris Kirtley
    Last modified on Thursday, 06-Jun-96 14:59:09.