Many people with cerebral palsy find walking a challenge. Tight muscles, spasticity, joint problems, poor balance and the poor alignment and position of certain bones can all cause problems. As the person ages, these issues can worsen, causing other complications that can further reduce mobility.
2D Gait Analysis is used to visually assess a person’s gait (walking style) in order to identify if they have any issues impacting on walking which should be corrected.
The purpose of 2D Gait Analysis is to assess a person’s ability to walk with an upright posture (postural control) and their walking style (gait patterns). This is known as a kinematic analysis. Problems can be identified and interventions introduced to help improve their gait, if needed.
A 2D Gait Analysis can be used for people with cerebral palsy of any age who can walk (GMFCS Levels I-III).
A 2D Gait Analysis is carried out by an experienced clinician, who will take a video recording of a person walking along a walkway (usually a number of times).
The clinician will assess the person’s movements at hip, knee and ankle level, and their overall posture.
Some of the movements that are assessed include stride time, length, stance time, swing time, joint angles and symmetry, comparing them to a typical walking style1. They will be analysed from the front, side and back.
Afterwards, the video recording of the person walking is played back in slow-motion. 2D Gait Analysis software may also be used to help analyse their gait and identify any problems.
The health professional can then use this assessment information to determine the best interventions for them. Treatments may include goal-directed training, wearing ankle foot orthoses and possibly even surgery, depending on how severe their gait problems are.
The amount of time it takes to complete this assessment is between 10 and 30 minutes. Additional time is required for the video to be analysed and for any report writing. In total, a thorough kinematic analysis of a gait video can take between one to two hours.
Fees will apply for a physiotherapist to conduct this assessment. The cost will depend on the provider. You should also check with your practitioner to see if there will be additional costs to prepare a home program, travel to the sessions or prepare a report.
You should ask your service provider if you are eligible for funding to assist with fees. People with a disability living in Australia may also be eligible for a health care rebate through Medicare or funding from the National Disability Insurance Scheme.
This assessment should be conducted by a qualified health professional with experience assessing gait.
There are costs to purchase the essential equipment for this assessment which includes a video camera and kinematic analysis software.
Another possible cost is the brightly coloured markers that are sometimes placed on specific joints to help detect movement and improve test reliability.
Construct validity – Criterion validity of 2D gait analysis has been assessed against 3D gait lab analysis. The results from this single study indicate excellent (ICC = 0.95-0.99) criterion validity in all areas except for sit-to-stand items which showed fair to excellent (ICC = 0.59-0.93) criterion validity3. This means, according to this single study, 2D gait analysis is a valid measure to assess gait when compared to the gold standard 3D gait lab analysis.
Reliability – Reliability has been assessed in one study and shows good to excellent test-retest (ICC = 0.7-1.0) and inter-rater (ICC = 0.76-1.0) reliability3. Sit-to-stand movement again showed the lowest reliability when assessed with 2D Gait analysis (ICC = 0.7-0.9)3.
Responsiveness – There are no available studies which have measured responsiveness of 2D Gait analysis. To improve the reliability of 2D gait analysis, video quality should be considered. This includes the quality of the video camera, lighting and position. Specifically, it is recommended to use a good quality camera, a tripod to hold the camera steady, adequate lighting, to position the camera at the right height and distance and use marker placement on the participant4. It is also important to ensure that the markers are placed on exactly the same spots for any consecutive assessments1.
Note: Assessments should have strong psychometric properties. These properties refer mainly to i) validity – whether the tool measures what it is meant to measure, ii) reliability – whether the results of the tool are stable under different conditions and, for tools which measure outcome iii) responsiveness – whether the test is responsive to change.
The information on this page was developed using the best research evidence combined with the expertise of clinicians and people with cerebral palsy and their families. It is provided to help people with cerebral palsy, their families and caregivers, clinicians and service providers make decisions about suitable interventions. This information is intended to support, but not replace, information exchanged, and decisions made, between people with cerebral palsy, their families and health professionals.