Anatomy of Hind Limb Bones Quiz

The Hind Limb

• The hind limb consists of the hip, thigh, leg, and pes.
• The hip bone is the largest flat bone in the body and is formed by the union of the ilium, ischium, and pubis at the acetabulum.

The Os Coxae (Hip Bone)

• The os coxae is composed of the ilium, ischium, and pubis.
• The pelvic girdle includes the os coxae of either side.
• The bony pelvis includes the os coxae, sacrum, and first 3 coccygeal vertebra.
• The ilium is the largest of the three parts and is irregularly triangular in shape.
• The ilium presents two surfaces, three borders, and three angles.
• The medial angle is termed the tuber sacrale.
• The lateral angle, tuber coxae, forms the basis of the point of the hip.
• The acetabular angle meets the other two bones at the acetabulum.

The Ischium

• The ischium has four borders and two surfaces.
• It has two rami, with the medial ramus forming the symphysis and the lateral ramus going to the acetabulum.
• The obturator foramen is oval in shape.

The Pubis

• The pubis has dorsal and ventral surfaces and cranial and caudal borders.
• It has a pubic tubercle, pubic groove, and iliopubic eminence.
• The pubis has two rami, with the medial ramus forming the symphysis and the lateral ramus going to the acetabulum.

Comparison of Os Coxae in Different Animals

• In horses, the ilia gluteal line is un-parallel to each other and from the dorsal to the medial border.
• In oxen, the ilia gluteal line is parallel to each other and parallel to the lateral border.
• In dogs, the wings are very concave.

The Femur (Thigh Bone)

• The femur is a long bone that forms joints at the hip and stifle.
• The proximal extremity bears trochanters (greater, lesser, and third) and a head with a fovea capitis.
• The shaft forms a blunt point directed distally.

The Tibia and Fibula (Leg Bones)

• The tibia and fibula are long bones that form joints at the stifle and hock.
• The proximal extremity of the tibia bears two condyles, two spines, and cranial and caudal intercondylar areas.
• The tibia has a tibial tuberosity and tibial crest.
• The shaft is prismatic at the proximal third.
• The distal extremity forms the medial malleolus.
• The fibula is a much-reduced bone that lies lateral to the tibia.
• The distal extremity of the fibula forms the lateral malleolus.

Comparison of Tibia and Fibula in Different Animals

• In horses, the tibial tuberosity is grooved, the shaft is straight, and the distal articular surface is divided.
• In oxen, the tibial tuberosity is not grooved, the shaft is oblique, and the distal articular surface is double curved.
• In dogs, the tibial tuberosity is not grooved, the shaft is twisted, and the distal articular surface is sagittal.

The Tarsus (Hock)

• The tarsus or hock of the horse usually comprises six short bones, but exceptionally seven are present.
• The tibial tarsal bone is the medial bone of the proximal row and is extremely irregular in form.
• The fibular tarsal bone is the largest bone of the hock and has a tuber calcis or "point of the hock".