Page 105 - Anatomy and Physiology of Farm Animals, 8th Edition

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Dorsal Plantar
VetBooks.ir

T Cal
T
Cal

C C
4 4
3 1
S

V IV III II II III IV V

Figure 4-17. Porcine tarsus. Cal, calcaneus; T, talus; c, central tarsal bone; 1–4, numbered tarsal bones;
II–V, metacarpals.

the hock. The horse has both the proximal talus dorsally has two spool‐like ridges for
end and a portion of the shaft, whereas articulation with the tibia. The calcaneus
only a vestige of the proximal end of the projects proximad and caudad to form the
fibula is present in domestic ruminants. All point of the hock. The calcaneus, which
domestic species have the distal extremity corresponds to the human heel, acts as a
of the fibula, forming the prominent lat- lever for the muscles extending the hock.
eral malleolus of the hock. The lateral In the horse, the central row of tarsal
malleolus is fused to the tibia in the horse bones is reduced to a single central tarsal
but is a separate small bone articulating bone. The bones of the distal row are num-
with distal tibia and tarsal bones in bered 1 to 4 from medial to lateral, with
ruminants. tarsal bones 1 and 2 fused into a single
The tarsus (hock), like the carpus in the bone. In cattle, tarsal bones 2 and 3 are
thoracic limb is composed of multiple fused, as are the central and 4th.
small bones; it corresponds to the human The metatarsus and digits of the pelvic
ankle (Fig. 4‐17). The proximal row of tar- limb are similar to the metacarpus and
sal bones consists of two large bones. The digits of the thoracic limb.