Effects of Acceleration on Ground Reaction Forces Collected in Healthy Dogs at a Trot

Summary

The aim of this study was to assess, whether or not, visual grading of changes in subject acceleration during force plate collection within a fixed, measured velocity range was adequate to control acceleration/deceleration. A second question was, whether or not, visual grading of the trials was adequate to prevent significant changes in ground reaction forces within a controlled velocity range. Eight healthy, non-chondrodysplastic dogs, of varying breeds, were used in the study. Each dog was tested in four different protocols. The order in which the dogs completed the different protocols was determined randomly. During all of the protocols, the dogs trotted across the measured testing area within a velocity range of 1.6 to 1.9 m/s. The protocols varied in the amount of acceleration or deceleration allowed in the testing area and the methods of evaluating the acceleration or deceleration. Significant differences in ground reaction force measurements were found, with variations in the acceleration and deceleration. The majority of changes were found in the craniocaudal axis during acceleration and deceleration. Vertical axis measurements were only altered in the rear limbs. Significant differences were not found in any measurement (except the stance phase duration in the rear limb) between the mechanically controlled minimal acceleration/deceleration variation protocol and the visually controlled acceleration/deceleration variation protocol. While visual observation was unable to consistently differentiate acceleration, or deceleration, changes through the testing area, it was able to eliminate enough variation in ground reaction force measurements so that differences were not found between the mechanically controlled minimal acceleration/ deceleration variation protocol nor the visually controlled acceleration/deceleration variation protocol. These results suggest that either method of collection may be acceptable for data collection depending upon the type of study being performed.

The effects of acceleration variation were examined in dogs undergoing force plate gait analysis. Significant differences in ground reaction force measurements were found, with variations in the acceleration and deceleration. The majority of changes were found in the craniocaudal axis, during acceleration and deceleration. Visual observation was unable to consistently differentiate variations in acceleration through the testing area.

Keywords

Gait analysis - ground reaction forces - acceleration

• REFERENCES

• 1 Budsberg SC, Verstraete MC, Soutas-Little RW. Force plate analysis of the walking gait in healthy dogs. Am J Vet Res 1987; 48: 915-8.
• 2 Budsberg SC, Chambers JN, Van Lue SL. et al Prospective evaluation of ground reaction forces in dogs undergoing unilateral total hip replacement. Am J Vet Res 1996; 57: 1781-5.
• 3 Budsberg SC, Johnston S, Schwarz P, DeCamp C, Claxton R. Evaluation of Etodolatj for the treatment of osteoarthritis of the hip in dogs: A prospective multi-center study. Vet Surg 1996; 25: 420-1.
• 4 Budsberg SC, Jevens DJ, Brown JB. et al Evaluation of limb symmetry indices using ground reaction forces in healthy dogs. Am J Vet Res 1993; 54: 1569-74.
• 5 Cross AR, Budsberg SC, Keefe T. Efficacy of Meloxicam in a canine acute synovitis model. Am J Vet Res 1997; 58: 626-32.
• 6 Jevens DJ, Hauptman JG, DeCamp CE. et al Contributions to variance in force plate analysis of gait in dogs. Am J Vet Res 1993; 54: 612-5.
• 7 McLaughlin RM, Roush JK. Effects of increasing velocity on braking and propulsion times during force plate gait analysis in greyhounds. Am J Vet Res 1995; 56: 156-61.
• 8 McLaughlin RM, Roush JK. Effects of subject stance time and velocity on ground reaction forces in clinical normal greyhounds at the trot. Am J Vet Res 1994; 55: 1666-71.
• 9 Riggs CM, DeCamp CE, Soutas-Little RW. et al Effects of subject velocity on force plate measured ground reaction forces in healthy greyhounds at the trot. Am J Vet Res 1993; 54: 1523-6.
• 10 Roush JK, McLaughlin RM. Effects of subject stance time and velocity on ground reaction forces in clinically normal greyhounds at the walk. Am J Vet Res 1994; 55: 1672-6.
• 11 Rumph PF, Lander JE, Kincaid SA. et al Ground reaction force profiles from force platform gait analyses of clinically normal mesomorphic dogs at the trot. Am J Vet Res 1994; 55: 756-61.