Kinetic gait analysis in healthy dogs and dogs with osteoarthritis: An evaluation of precision and overlap performance of a pressure-sensitive walkway and the use of symmetry indices

Abstract

In veterinary practice, a thorough gait examination is essential in the clinical workup of any orthopedic patient, including the large population of dogs with chronic pain as a result of osteoarthritis. The traditional visual gait examination is, however, a subjective discipline, and systems for kinetic gait analysis may potentially offer an objective alternative for gait assessment by the measurement of ground reaction forces. In order to avoid unnecessary testing of patients, a thorough, stepwise evaluation of the diagnostic performance of each system is recommended before clinical use for diagnostic purposes. The aim of the study was to evaluate the Tekscan pressure-sensitive walkway system by assessing precision (agreement between repetitive measurements in individual dogs) and overlap performance (the ability to distinguish dogs with lameness due to osteoarthritis from clinically healthy dogs). Direction of travel over the walkway was investigated as a possible bias. Symmetry indices are commonly used to assess lameness by comparing ground reaction forces across different combinations of limbs in each dog. However, SIs can be calculated in several different ways and specific recommendations for optimal use of individual indices are currently lacking. Therefore the present study also compared indices in order to recommend a specific index preferable for future studies of canine osteoarthritis. Forty-one clinically healthy dogs and 21 dogs with osteoarthritis were included in the study. High precision was demonstrated. The direction of travel over the walkway was excluded as a possible bias. A significant overlap was observed when comparing ground reaction forces measured in dogs with osteoarthritis compared to clinically healthy dogs. In some affected dogs, symmetry indices comparing contralateral limbs differed from clinically healthy dogs, but in general, the overlap performance was insufficient and, consequently, general use of this method for diagnostic purposes in dogs with osteoarthritis cannot be recommended.

Characterization of Weight-bearing Compensation in Dogs With Bilateral Hip Osteoarthritis

“…34,35 SIs are standardized comparisons of individual limbs, being a specific and reliable evaluation of individual limbs. 36 Our results contrast with this finding, which may be related to the fact that all animals exhibited bilateral disease, and therefore may try to relieve the pelvic limbs by transferring weight to the thoracic limbs. Also, a weak, although significant, the correlation was found between individual pelvic limbs and the opposing contralateral thoracic limb.…”

Effect of a single intra-articular administration of stanozolol in a naturally occurring canine osteoarthritis model: a randomised trial

“…This effect is observable in the Kaplan Maier test results for SI, with results of the stanozolol group taking significantly longer to return to baseline values. SI is commonly used to assess lameness, but their calculation with pressure-sensitive walkways has some limitations in OA patients 29 . While it is still unknown if the same limitations apply to the static evaluation of weight-bearing, we looked at different weight-distribution compensation mechanisms by calculating SI and deviation values.…”

“…SIs allows for a standardized comparison of ground reaction forces obtained from different individual limbs, eliminating the need to normalize data between subjects. It is considered a specific, sensitive, suitable and reliable assessment of limb dysfunction 29 . Lower SI indicates that the animals is showing a more even distribution of body weight between limbs.…”

Simple Video-Based Spatiotemporal Gait Analysis Is Not Better than Subjective Visual Assessment of Lameness in Dogs

“…Pressure mat data for some of these dogs have been previously reported. 16 Data were excluded from three dogs due to missing/corrupted files (1 dog) and inability to extract hindlimb data (2 dogs). The mean age of the 35 dogs included in the analysis was 4 years, 1 month (SD: 15 months), mean weight was 27 kg (SD: 6.6 kg), and shoulder height was 54 cm (SD: 6.1 cm).…”