Our environment is fully loaded with inclined or slippery surfaces and various types of other obstacles. Dogs with impaired locomotion might have difficulties to adapt their gait pattern to manage this complex of problems. Most of the gait analyses regarding the limb loads are limited to level surfaces. Therefore, the aim of this study was to determine the effect of cross-slope walking in ten healthy Labrador Retrievers using a pressure plate walkway system which was positioned on a level surface and also using a 10° and 15° lateral elevation angle. Velocity, step length, peak vertical force and vertical impulse were determined. The results of this study indicate that dogs show significant asymmetrical compensations between the up-slope and down-slope paws when cross-slope walking. The vertical impulse was a more sensitive measure than the peak vertical force. A compensation mechanism was detectable as a decrease of ground reaction forces (GRFs) of the up-slope hindlimb as well as an increase of GRFs of the down-slope forelimb. The other diagonal limb pair was less affected.
Initially the dogs shifted more weight onto the down-slope hindlimb and reduced load on the up-slope forelimb, but in subsequent trials these values increasingly approached those seen in level walking. Also the step length was decreased during cross-slope conditions. The findings of this study support the hypothesis that substantial musculoskeletal adaptations are required to manage cross-slope walking and further, that dogs with impaired locomotion might have difficulties to adapt their gait pattern to compensate the functional leg length discrepancy caused by the cross-slope.