Page 73 - Adams and Stashak's Lameness in Horses, 7th Edition

Functional Anatomy of the Equine Musculoskeletal System 39

VetBooks.ir Peroneus tertius m.

Tibialis cranialis m.

Proximal extensor
retinaculum

Cranial tibial v.

Anastomotic branch

Deep peroneal n.
Cranial branch of medial
saphenous v.
Dorsal pedal v. & a.

Middle extensor Dorsal tendon of tibialis
retinaculum cranialis m.

Lateral dorsal metatarsal n. Medial tendon of tibialis
(over proximal cranialis m.
perforating vessels)
Medial dorsal metatarsal n.
Lateral digital
extensor tendon Dorsal tendon of peroneus
tertius m.
Dorsal common digital v. II
Dorsal metatarsal a. III

Figure 1.36. Dorsal dissection of right tarsus. The long digital that the term “fibularis” has superseded “peroneus” (fibular rather
extensor and short digital extensor muscles have been removed. than peroneal), although both are widely used.
The lateral tendon of the fibularis tertius is sectioned. Please note

the tarsus. Branches from the saphenous and tibial The bursa between the cunean tendon and the distal part
nerves supply sensory innervation to the medial aspect of the long medial collateral ligament of the tarsus is not
of the tarsus. The large cranial branch of the medial normally palpable (Figure 1.37). The tendon of the medial
saphenous vein courses subcutaneously, superficial to digital flexor (a.k.a. medial head of the deep digital flexor
the dorsomedial pouch of the tarsocrural joint capsule. muscle or long digital flexor muscle) passes through
At the level of the medial malleolus of the tibia, it sends a fascial tunnel plantar to the medial collateral ligament.
a small anastomotic branch to the cranial tibial vein. A synovial sheath surrounds this tendon from the distal
The caudal branch of the medial saphenous vein receives fourth of the tibia to the tendon’s junction with the main
blood from branches in the medial and plantar regions tendon of the deep digital flexor (Figure 1.39). A com­
of the hock. partment of the tarsocrural joint capsule, the medioplan­
A palpable feature of the medial aspect of the hock is tar pouch, is located a short distance plantar to the medial
the medial (cunean) tendon of the cranial tibial muscle digital flexor tendon and proximal to the sustentaculum
as it inserts on the fused first and second tarsal bone. tali of the calcaneus at the level of the medial malleolus.