Page 103 - Anatomy and Physiology of Farm Animals, 8th Edition

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Dorsal
VetBooks.ir Tuber coxae Ilium

Tuber sacrale
Lateral Pubic symphysis
Tuber sacrale
Tuber coxae Sacrum

Obturator
foramen
Ischium

Ilium
Tuber
ischiadicum

Ischium
Acetabulum
Pubis

Figure 4-15. The pelvis of the horse. Lateral (left) and dorsal (right) views.

The pubis, the smallest of the three pel- the tendon of insertion of the large quadri-
vic bones, forms the cranial part of the ceps muscle.
floor of the pelvic cavity. The pubis also The tibia and fibula are the bones of
enters into the formation of the acetabu- the true leg (crus), the portion of the pelvic
lum and meets the pubis of the opposite limb between stifle and hock. The tibia, the
side at the symphysis. The pubis and larger of the two, is palpable beneath the
ischium form the boundaries of the obtu- skin medially. The fibula, which is much
rator foramen. smaller, lies on the lateral side of the leg. It
The femur (thigh bone) extends from is a complete, albeit slender bone in porc-
the coxofemoral (hip) joint to the stifle ids, but in ruminants and equids, the fibula
(the joint corresponding to the human is reduced. In the ruminant crus, it exists
knee) (Fig. 4‐16). The proximal end of the as two separate nodular bones, one present
femur has a nearly spherical head that at each end of the lateral crus. In the horse,
articulates with the acetabulum of the os the fibula assumes a slender tear‐drop
coxae to form the hip joint. There are also shape in the proximal crus.
several roughened prominences (two in The tibia has an expanded proximal end
ruminants and swine, three in horses) that participates in the stifle joint. Its shaft
called trochanters, for the attachment of is triangular in cross‐section. The distal
heavy thigh and hip muscles. The straight end of the tibia has two concave depres-
diaphysis (Fig. 4‐3) of the femur is nearly sions that form the hinge joint of the hock
circular on cross‐section. The distal end with the talus (tibiotarsal bone).
has two condyles for articulation with the In the dog, pig, and humans, the fibula is
tibia and a trochlea for articulation with a long, thin bone extending from the proxi-
the patella, a sesamoid bone embedded in mal end of the tibia to the lateral aspect of