Quantitative Gait Analysis Detects Significant Differences in Movement between Osteoarthritic and Nonosteoarthritic Guinea Pig Strains before and after Treatment with Flunixin Meglumine

Figure 3

Representative still images of data output provided by the computer-aided gait analysis system for one OA-prone Hartley guinea pig and one OA-resistant Strain 13 guinea pig at baseline and 4 hours after treatment. Top images of each data set are photographs of streaming video footage collected by the underlying camera. Computer-constructed paw prints utilized for data analysis are presented in the middle image. Bottom images show the length of time when each individual paw is in contact with the glass surface. Time (in 5-second intervals) is denoted by vertical yellow, dashed lines; vertical black, dashed lines designate where live videos correspond to individual paw prints. Paw prints are color-coded, as indicated. As walking is a four-beat gait, three paw prints are in contact with the ground at any one time. Elapsed time of each particular run and gait parameters (mean ± 95% confidence intervals) for each group are provided. At 4 (shown) and 24 hours after treatment, single administration of flunixin meglumine permitted OA-prone animals to move with a gait profile that was not significantly different from OA-resistant animals.

(a) OA-prone Hartley guinea pig (untreated)

(b) OA-prone Hartley guinea pig (4 hours after treatment with NSAID)

(c) OA-resistant Strain 13 guinea pig (untreated)

(d) OA-resistant Strain 13 guinea pig (4 hours after treatment with NSAID)