Distal intertarsal and tarsometatarsal joints in the horse: communication and injection sites.

This study examines the connection and injection sites of the distal intertarsal and tarsometatarsal joints in the horse, finding that a “pop” sound during high-pressure injections does not necessarily indicate joint communication, and providing optimal points for puncturing these joints.

Study Method and Materials

• The framework of this study relied on the examination of 103 equine hocks procured from the postmortem room.
• The primary focus of the research was the distal intertarsal and tarsometatarsal joints.
• Any hocks with fused central and 3rd tarsal bones were excluded from the examination.

Communication Between Joints

• The research found that there was a communication between the distal intertarsal and tarsometatarsal joints in 8.3% of low-pressure injected hocks and 23.8% of high-pressure injected hocks.
• This communication was observed by dissecting the injected material through two internal spaces – the tarsal canal, and the space amid the combined first and second tarsal bones and the third tarsal bone.
• Notably, the study underscores that a “pop” sound, occasionally observed during high-pressure injections, is not a definite correlate of an established communication between the two joints.

Injection Sites

• The research determined the most effective locations for puncturing the joints.
• For the distal intertarsal joint, the optimal injection point was identified medially through the proximal part of the space between the combined first and second tarsal bones, the third tarsal bone, and the central tarsal bone.
• The tarsometatarsal joint was most reliably punctured plantarolaterally between the head of the fourth metatarsal and the fourth tarsal bones.