All about the hock joint

The hock joint is a complex joint, comprising of several articulations between the tibial bone, tarsal bones and the third metacarpal bone.

The joints within the hock joint:

• The tarsocrural joint, which is the articulation between the distal aspect of the tibia and the proximal aspect of the tarsal bone. The tarsocrural joint is the joint of highest motion, capable of flexion and extension, accounting for 90% of the range of motion.  
• The proximal intertarsal joints is the articulation between the distal surface of the talus bone, the proximal surface of the central tarsal bone, the first and second fused and the fourth tarsal bone (the first row of tarsal bones).
• The distal intertarsal joints is the articulation between the distal surface of the central tarsal bone and the proximal surface of the third tarsal bone (second row of tarsal bones).
• The tarsometatarsal joint is the articulation between the third and the fourth tarsal bones and the proximal aspect of the third metacarpal bone.
• The proximal intertarsal, distal intertarsal, and tarsometatarsal joints are plane joints and are capable of only small amounts of gliding (shear) movement and account for the remaining 10% of range of motion.
• The talocalcaneal joint is the curved articulation between the planter surface of the talus bone and the craniodistal surface of the calaneous bone.

There is outward rotation of the third metatarsal bone during the swing phase, followed by a small inward rotation during stance, when the hock is compressed. As a result, during gallop the hindlimbs swing outside the forelimbs as the tarsus flexes and then move back toward the midline as the tarsus extends before landing, avoiding contact with the abdomen.
 
The hock joint is much lower than people expect, as shown in the images, and that’s why it is so important to know your musculoskeletal anatomy and exactly where the articulating bones are, in order to assess the functionality of the joint, perform stretches and mobilisations that affect the joint and apply modalities in the most effective way.

The hock joint is most commonly affected by osteoarthritis and this most commonly occurs within the distal intertarsal joints and the tarsometatarsal joints as their function is to absorb concussive forces during locomotion.

​How can I help?

• Photizo light therapy to the distal tarsal joints to relieve joint pain and reduce inflammation.
• Massage will help to relieve tension and secondary discomfort caused by hock joint pain and compensatory postural changes.