Appendicular Skeleton• Bones of limbs.– Thoracic limbs (front leg)

• Scapula• Humerus• Radius• Ulna• Carpal bones• Metacarpal bones• Phalanges

– Pelvic Limbs (back leg)• Pelvis

– Ilium– Ischium– pubis

• Femur• Tibia• Fibula• Tarsal bones• Metatarsal bones• Phalanges

Appendicular Skeleton Appendicular Skeleton (limb bones)(limb bones)

Thoracic Limb• ScapulaScapula• HumerusHumerus• RadiusRadius• UlnaUlna• Carpal bones (carpus)Carpal bones (carpus)• Metacarpal bonesMetacarpal bones

• PhalangesPhalanges

Scapula

• Most proximal bone of the thoracic limb.• Flat and triangular.• Has prominent ridge on lateral surface referred to as the

_____________.• The distal end forms portion of ball and socket shoulder joint called

the ______________ cavity.

Humerus

• Long bone of upper arm/brachium

• Articulates with the _________ proximally and the _______ and _______ distally

• Has head at proximal end with a large greater tubercle for muscle attachment.

• Condyle at distal end is composed of trochlea (medial/ulna), capitulum (lateral, radius), medial and lateral epicondyles (medial and lateral/ no articulations)

• _____________ fossa is proximal to the condyles on the caudal surface of the humerus

• Is not the “funny bone”

• One of two bones that form the antebrachium.• Proximally, forms major portion of elbow joint with distal end of the

____________.• Articulates distally with the ________ (except in the horse).• Point of the elbow = olecranon process

• Trochlear _________: concave articular surface that makes elbow secure.– Proximal end of trochlear notch forms a beak-shaped ______________ process.

• tucks into the olecranon process of the humerus– Distal end of trochlear notch forms the two ________________ processes.

• Styloid process forms the distal end of the ulna.

Radius

• Main weight bearing bone of the antebrachium.• Articulates with _________ and ulna proximally, and the

_______ distally.– ___________process articulates with carpus.

Carpal Bones• Carpus has _______ rows of bones.• Is the “_______” of the most animals, knee

of horses• Proximal row bones have names

– radial carpal bone, intermediate carpal (if present) ulnar carpal bone, accessory carpal bone

• Distal row bones numbered medial to lateral:– (1st carpal, 2nd carpal, etc)

Metacarpal Bones

• Articulate proximally with the carpal bones and distally with the phalanges of the digits.

• Numbered from _________ to _________ (dewclaw being number 1 in dogs and cats).

• Horses have one large metacarpal III bone (__________ bone) and two non-weight bearing metacarpal II & IV bones (___________ bones).

• Cattle have fused metacarpal bones (III & IV) with a groove dividing them

EQUINE

Phalanges (singular = phalanx)

• Each digit is made up of two or three______________ (proximal, middle, distal)

• In horses phalanges are also called the long and short pastern bones and coffin bone.

• Horses and cattle have proximal and distal sesamoid bones. – Distal sesamoid in horse = navicular

bone

• Horses have one weight-bearing digit (III) and cattle have two (III & IV)

• Dogs and cats have an _____________ crest that surrounds the claw.

EQUINE PHALANGES

LONG PASTERN

SHORT PASTERN

COFFIN BONE