Lameness Localization in Dogs: An Exploratory Study of the Translation of the Equine Flexion Test to Canine Orthopaedics

Objectives The aim of this study was to describe the method and feasibility of the flexion test (FT) as a diagnostic tool to localize lameness on dogs. Study Design Canine FT was designed and based on the FT routinely used on horses. In dogs, the test consisted in a flexion of a joint to its full range of motion for 1 minute. Eventual increased lameness was then evaluated. The gait was evaluated using a visual analogue scale. An increase in the lameness score compared with the baseline score was considered as a positive result.The method was described for every major joint of the appendicular skeleton and was evaluated in sound and lame dogs. To evaluate the feasibility, the FT was applied for 3 minutes in eight healthy dogs on all joints. On 27 clinically lame dogs, flexion was applied for 1 minute on the joints with a suspected pathology and on their contralateral side used as a control. Results The FT was feasible and well tolerated by the sound dogs on all joints and no positive results were recorded. On clinically lame dogs, lameness increased in 81.5% of dogs. These cases were afterwards diagnosed with an orthopaedic-related disorder and then defined as true positives. False negative results occurred in 18.5% of the lameness cases. Conclusion The FT is safe and easy to perform. It did not produce any false positive results. False negatives might occur in a minor number of cases, implying that a negative result does not exclude a joint pathology.