[Illustration:
FIG. 75.—RIGHT TARSUS AND UPPER PART OF METATARSUS OF HORSE, INTERNAL
VIEW. (After Schmaltz, Atlas d. Anat. d. Pferdes.)
]
[Illustration:
FIG. 76.—RIGHT TARSUS AND UPPER PART OF METATARSUS OF HORSE, POSTERIOR
(PLANTAR) VIEW. (After Schmaltz, Atlas d. Anat. d. Pferdes.)
]
The =fibular tarsal= bone (Os tarsi fibulare, calcaneum, os calcis) is
the largest bone of the hock. It is elongated, flattened from side to
side, and forms a lever for the muscles which extend the hock joint. It
consists of a body and an inner process, the sustentaculum tali.
[Illustration:
FIG. 77.—RIGHT TIBIAL TARSAL BONE OF HORSE, ANTERIOR VIEW. (After
Schmaltz, Atlas d. Anat. d. Pferdes.)
]
[Illustration:
FIG. 78.—RIGHT TIBIAL TARSAL BONE OF HORSE, EXTERNAL VIEW. (After
Schmaltz, Atlas d. Anat. d. Pferdes.)
]
The =body= (Corpus calcanei) is enlarged at its proximal end to form the
=tuber calcis= or “point of the hock.” The posterior part of this
eminence gives attachment to the tendon of the gastrocnemius, while in
front and laterally it furnishes insertion to tendons of the flexor
perforatus, biceps, and semitendinosus muscles. The =inferior extremity=
bears a concave facet for articulation with the fourth tarsal bone. The
=internal surface= has on its lower part a strong process, the
=sustentaculum tali=, which projects inward. The process has a large,
oval, slightly concave facet in front for articulation with the tibial
tarsal, and sometimes a small articular surface below for the central
tarsal bone. Its plantar surface forms with the smooth inner surface of
the body a groove for the deep flexor tendon (Sulcus musculi flexoris
hallucis longi). Its inner surface has a prominence on the lower part
for the attachment of the lateral ligament. The =external surface= of
the body is flattened, except below, where there is a rough prominence
for the attachment of the lateral ligament. The =anterior= or =dorsal
border= is concave in its length, smooth and rounded in its upper part.
About its middle is a blunt-pointed projection (Processus cochlearis)
which bears facets on its inner and lower surfaces for articulation with
the tibial tarsal bone, and is roughened outwardly for ligamentous
attachment. Below this are two facets for the tibial tarsal, and an
extensive rough fossa which concurs in the formation of the sinus tarsi.
The =posterior= or =plantar border= is straight and thick, and widens a
little at either end; it is rough, and gives attachment to the long
plantar ligament.
[Illustration:
FIG. 79.—RIGHT FIBULAR TARSAL BONE OF HORSE, ANTERIOR VIEW. (After
Schmaltz, Atlas d. Anat. d. Pferdes.)
]
[Illustration:
FIG. 80.—RIGHT FOURTH TARSAL BONE OF HORSE, UPPER SURFACE. (After
Schmaltz, Atlas d. Anat. d. Pferdes.)
]
[Illustration:
FIG. 81.—RIGHT CENTRAL TARSAL BONE OF HORSE, UPPER SURFACE. (After
Schmaltz, Atlas d. Anat. d. Pferdes.)
]
[Illustration:
FIG. 82.—RIGHT FIRST, SECOND, AND THIRD TARSAL BONES OF HORSE, UPPER
SURFACE. (After Schmaltz, Atlas d. Anat. d. Pferdes.)
]
[Illustration:
FIG. 83.—PROXIMAL ARTICULAR SURFACES OF LEFT METATARSAL BONES OF
HORSE. (After Schmaltz, Atlas d. Anat. d. Pferdes.)
]