244 Gait changes in the aging canine.

Abstract With aging comes changes in gait and mobility in our companion animals. While aspects of these mobility changes have been quantified in humans, less have been identified in dogs. The aim of this retrospective data analysis was to identify age-related gait changes in Labrador Retrievers. Data collected in March of 2018 was available on 65 dogs, of which 34 had data collected again in August of 2024 and were at that time without known mobility issues based on kennel records. Of those 34 dogs, 16 (8 males, 8 females) had reached at least 10 years of age and were used in the final data analysis. Average age at the first data collection was 5.5 years old, and after the 6 year span average age increased to 11.9 years and body weights at this time averaged 31.8 ± 3.18 kg. Gait was analyzed using the Gait4Dogs system which measures spatial, temporal, and pressure variables for each limb. For each variable, the sum of the front limb or left limb values were divided by the sum of the hind limb or right limb values to generate the front:hind (H:R) or left:right (L:R) ratios, respectively. The average value for each gait variable was also calculated. Data were analyzed in SAS using a repeated measures mixed model with fixed effects of time. Age in 2018 was included as a covariate and type 1 sum of squares was performed. Sex was included as a random effect and dog as the repeated subject. We observed significant decreases in cadence, average step length, average stride length, and average swing percentage of cycle (P ≤ 0.05). Conversely, average step time, cycle time, swing time, stance percentage of cycle, and stance time all increased as dogs aged (P ≤ 0.05). Front:hind ratios for step time, cycle time, swing percentage of cycle, and swing time all decreased over time (P ≤ 0.01), while stance percentage of cycle and stance time F:H ratios increased (P ≤ 0.01). Overall, we observed that as Labrador Retrievers aged, they developed slower gaits with reduced step and stride lengths and a shift towards spending more time in the stance phase.