RIVCAM: a simple video-based kinematic analysis for clinical disorders of gait.
This paper describes the development of and reports on the accuracy of the Rivermead video-based clinical gait analysis method (RIVCAM), a simple and comparatively inexpensive movement recording system, which operates at 50 Hz. The system comprises five basic steps; firstly subjects are recorded using a PAL video camera with white markers affixed to the leg. Second, the video footage is digitised onto a computer. Thirdly, a program analyses each frame of footage to locate the position of white markers located on the subject's leg. Fourth, the data are calibrated (turned into real world co-ordinates) and the markers on the legs are identified (such as, heel, toe, etc.). Finally, a kinematic analysis is performed on the data, which not only produces a range of relevant spatio-temporal parameters (such as gait velocity, cadence and stride length), but also determines the joint angles at the hip, knee and ankle during the gait cycle. Overall the system has a reasonable constant and variable error; in a recorded scene measuring 2.6 x 1.6 m and divided into a 3 x 3 grid, a 400 mm bar was recorded, on average, as being 401.1 mm with a standard deviation (S.D.) of 2.97 mm. Although not without shortcomings when compared with more expensive and complicated systems, the RIVCAM system represents a valid, reliable and affordable way of collecting objective measures of gait in a busy therapy setting.
Department of Psychology, University of Central Lancashire, Preston, PR1 2HE UK. achurchill@uclan.ac.uk
Andrew J G
AJ
Churchill
Peter W
PW
Halligan
Derick T
DT
Wade
D000328:Adult; D001696:Biomechanical Phenomena; D003627:Data Interpretation, Statistical; D005684:Gait / Q000502:physiology*; D020233:Gait Disorders, Neurologic / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008297:Male; D012016:Reference Values; D015203:Reproducibility of Results; D012984:Software; D014741:Video Recording