In vivo investigation of communication between the distal intertarsal and tarsometatarsal joints in horses and ponies.

This study explores how often communication happens between two types of joint in the legs—tarsometatarsal and distal intertarsal—of horses and ponies. According to the results, about 26% of the time, the materials injected into one joint were found in the other, suggesting a pathway between the two.

Research Design

The research involved an in vivo investigation, meaning it was performed on live models, specifically 27 horses and 12 ponies. The investigators sought to determine how often communication occurs between the tarsometatarsal and distal intertarsal joints—one in the hoof and one further up the leg—within these animals.

• A solution of diluted latex was injected into the tarsometatarsal joints of each study subject through a method known as the plantarolateral approach.
• After the injection, each horse and pony was made to walk 200 meters, presumably to allow the latex to potentially move from the injection site to other parts of the animal’s leg.

Data Collection and Results

Once the simple experiment was completed, necropsies were performed on the test subjects to check for the presence of latex in the distal intertarsal joints.

• In about 26% of the total number of tarsi—a term referring to the collection of several joints in the leg including the ankle (73 tarsi total in this study)—latex from the tarsometatarsal joint injections was also found in the distal intertarsal joints. This indicates that some level of communication between these two types of joint does indeed occur.
• In 3 of the tarsi, researchers also found latex in the proximal intertarsal and tarsocrural joints, suggesting the communication may be even more complex or widespread.

Implications of the Study

These findings imply that what happens in one part of a horse or pony’s leg may have effects in other parts too. This could have important implications for the treatment of injuries and illnesses in these animals. It also adds to our wider understanding of the locomotive system in horses and ponies and how their bodies function in general. Future research might consider how these communications impact the health of these animals and, perhaps, expand the investigation to other species.