Development of a Front Limb Support to Facilitate Weight Reduction in Horses with Ambulatory Difficulties

Abstract

In horses, severe limb injuries and other problems affecting ambulation are challenging to manage. Offloading the injured limb can result in secondary complications such as supporting limb laminitis (SLL), severely affecting quality of life and sometimes necessitating euthanasia. SLL results from increased load and decreased blood flow to the foot. There is a need to develop a dynamic device to reduce the load on the limbs while maintaining mobility and blood flow for the rehabilitation of horses with ambulatory difficulties. In this study, the unique biomechanics of the horse were considered in the design of a dynamic front limb weight support system. The development further had to consider complications associated with its use, such as pressure ulcers and other tissue trauma. Therefore, the design included silicone air pockets to be inflated and deflated in a programmable cycle. A series of three prototypes resulted in a front limb support (breastplate) intended for use with a computer-controlled rehabilitation lift. Iterative design modifications of the breastplate allowed to safely provide up to 50% front limb weight reduction while maintaining horse comfort. This is a significant step towards adjustable, dynamic ambulatory support with the ability to customize rehabilitation programs for horses with ambulatory difficulties.