Tarsocrural joint luxation in a horse.

This study documents the case of a 14-year-old horse experiencing a severe joint displacement in its right hind limb. Through the use of radiography, joint realignment, and long-term confinement, the horse managed to regain partial function and continues to maintain itself in pasture conditions, albeit with signs of severe joint degradation and limited mobility.

Context and Presentation

• The study involves a Quarter Horse Thoroughbred gelding that started displaying difficulty bearing weight on its right hind limb, accompanied by noticeable deviation of the tarsus, a cluster of bones in the hind limb.
• The horse was immediately admitted to the hospital upon noticing these symptoms.

Initial Diagnosis and Investigation

• A preliminary diagnosis of a tarsal joint luxation (dislocation) or fracture was made, which would account for the horse’s difficulty in bearing weight and the abnormal positioning of the tarsus.
• Radiography, a common imaging technique used in veterinary medicine, was used to confirm the diagnosis. It showed a complete luxation or displacement of the tarsocrural joint, which is a significant joint in the hock of horses, lying between tarsal and the tibia-crus bones.

Treatment and Post-Injury Management

• Minimal force was used to realign the dislocated joint, a procedure known as reduction.
• Post-treatment, the horse was confined to a box stall and its hind limb was placed in a full-length cast for 33 days. This was aimed at immobilising the joint to help with recovery and prevent re-dislocation.
• Box stall confinement was continued for a further 3 months after the removal of the cast, to limit movement and provide a controlled environment for further healing.

Follow-up and Long-Term Effects

• 18 months after the initial injury and treatment, the horse was reexamined. Mild lameness was evident (classified as grade 1 out of 5, implying minimal severity), indicating that the horse had regained partial function.
• However, the range of motion of the tarsus was significantly reduced, indicating some loss of joint flexibility due to the injury.
• Radiography at this point revealed extensive transformations suggestive of severe degenerative joint disease, likely a consequence of the initial joint dislocation.
• Despite these complications, the horse managed to maintain itself on pasture and was even used for light pleasure riding.