Overview
It has a lateral and a medial head. Unlike the dog, the cat has a soleus (m. soleus), which arises from the head of the fibula and joins the gastrocnemius tendon. Their tendons form the main part of the common calcanean tendon.
Origin
Lateral and medial supracondylar tuberosities of the femur.
Insertion
Calcaneal tuber (tuber calcanei).
Action
Extends the tarsus and flexes the stifle.
Innervation
Tibial nerve (n. tibialis).
Clinical relevance
- In feline aortic thromboembolism, almost always secondary to cardiomyopathy, a thrombus lodges at the aortic trifurcation. The pelvic limbs become paretic, cold and pulseless at the femoral artery, with pale or cyanotic pads; the gastrocnemius and cranial tibial muscles become firm and painful from ischaemic neuromyopathy. Reperfusion can cause hyperkalaemia.
- Diabetic neuropathy in the cat causes a plantigrade stance: the cat walks with its hocks on the ground.
- Rupture or laceration of the common calcanean tendon also makes the hock drop.