Letting dogs jump out of high car boots may boost their injury risk

Dog

Allowing dogs to jump out of bigger cars with higher boots, popularly known as ‘Chelsea tractors,’ subjects their front legs to undue forces, so potentially boosting their risk of injury, indicates experimental research published in this week’s Vet Record.

While UK legislation requires that dogs must be restrained while travelling in any vehicle, no such regulations exist for safe entry and exit from a back seat or car boot, say the researchers.

To try and gauge whether different height boots are associated with excess pressure loading, the researchers set up an experiment in which 15 healthy dogs (14 pedigree breeds, 1 mixed breed) jumped three times each from a platform adjusted to three different boot sill heights: 0.55, 0.65, and 0.75 metres.

Measurement of the biomechanical forces involved for each of these jumps showed that the pressure on the dogs’ front legs differed considerably between the three levels, progressively increasing in parallel with ‘boot’ height.

It rose by just under 13 per cent between the 0.55 and 0.65 metre heights, and by just under 11 per cent with a further 10 cm rise in height. Altogether, there was a 25 per cent difference in peak ground force pressure between the lowest and highest platform heights.

Further research is needed before a definitive link can be made between this type of pressure and the sorts of front leg injuries/conditions typically seen in dogs, caution the authors.

They conclude: “This study provides the first objective evidence to support the commonplace belief that allowing dogs to repeatedly jump clear from vehicles with high boot compartments may be inadvisable.”