Kinetic and kinematic evaluation in dogs with osteoarthritis secondary to hip dysplasia during physical activities

Abstract

Hip dysplasia (HD) affects several species and it is one of the most common orthopedic affections in dogs. This affection results in joint incongruence with persistent joint laxity caused by displacement between muscle and bone growing.The symptoms are variable according with severity of this affection. Commonly reported symptoms are correlated with dog`s locomotion such as lameness, movement reluctance, difficulty to sit and stand up, walk up and down stairs and ramps. This kind of symptoms are associated with biomechanical and pain alterations that could range from mild to exacerbate signals. Kinesiology has provided new tools to evaluate such alterations in a quantitative way by means of kinetic and kinematic studies. These kinds of evaluation suppress difficulties of the clinical observation.Our hypothesis is that discomfort and pain in dogs with HD promotes differences in locomotion during physical activities compared with healthy dogs. Therefore it is important to develop methods to assess these clinical signs during routine physical activities. We expect provide a better understanding of these signals and it could be a great tool to evaluate follow up treatments.Methodology: Group I - 20 dogs screened in Small Animal Surgical Service of FMVZ-USP with HD and osteoarthritis confirmed by radiographic exam. Group II - 20 healthy dogs without signals to HD in the radiographic exam. The radiographic exam will be required according with CBRV rules which will classify in categories A, B, C, D and E. Evaluation protocol: The selected dogs with owner consent will be submitted to clinical, kinetic and kinematic evaluation.Clinical evaluation: A questionnaire an visual analogue scales (VAS) will be fill according with dog`s physical activity by the owner and two blind veterinary examiners. The physical examination will be performed after kinetic and kinematic evaluation to do not interfere in results.Kinetic and kinematic evaluation: The dogs will be evaluated in tree tests using a pressure walkay to perform kinetic evaluation and by motion system analysis to perform kinematic analysis. Kinematic analysis will describe the movement during sit and stand up test and during up and down stairs and ramps. Kinetic evaluation will report vertical forces during walking. Statistical analysis: Comparisons will be performed between right and left sides as well as will be compared between group I and II. Kolmogorov-Smirnov will check normality of data distribution and the properly tests will be performed. All tests will use p < 0.05. Using VAS results, the inter-observer correlation will demonstrate the concordance. Linear regression also will be performed.We expect to detect differences and limitation of these dogs during physical activities to provide a new evaluation tool for the available treatments to HD.