Equine Anatomy
Skeletal and Muscular Systems
• Framework of the body
• FUNCTION:
– Support
– Protection of Vital Organs
– Movement
Joints
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Held together by ligaments
Provide movement
Where the bones meet
Some are immoveable, others provide a little
movement and others permit a wide range of
movement
Bones
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Skeleton consists of 206 bones
Provide the framework of the body
Has levers for movement
Attachment points for muscles
Protect vital organs
They are living tissue with blood vessels and nerves
Red blood cells are produced in the marrow
Contain protein and minerals (Ca& P)
Muscles
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Attached to bone by tendons
Move the bones
Made up of muscle fibers, arranged in bundles
Controlled by motor nerves that cause
contractions
Cartilage
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Smooth and firm, but flexible
Forms ears and nose
Covers articular surfaces of bones in joints
Allows bones to move smoothly (Absorbs
shock)
Tendons
• Strong, fibrous connective tissue that connects
MUSCLE TO BONE
• Tendon sheath protects a tendon containing
synovial fluid to lubricate the tendon as it
moves
Anatomical Planes of Reference
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Left
Right
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The animal’s left
The animals right
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Cranial
Rostral
Caudal
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Toward the head
Toward the tip of the nose (head only)
Toward the tail
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Dorsal
Ventral
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Toward the back
Toward the belly
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Medial
Lateral
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Toward the median plane
Away from the median plane
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Deep (internal)
Superficial (external)
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Toward the center (whole body or part)
Toward the surface (whole body or part)
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Proximal
Distal
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Toward the body (extremity)
Away from the body (extremity)
Anatomy of the Carpus
• The knee is made of two rows of short bones
• These same bones are the ones in a human wrist
• The upper row of bones are given names:
- Radial carpal bone, ulnar carpal bone, accessory carpal
bone, intermediate carpal bone
• The lower row of bones are given numbers instead of names
- the numbers start inside (medially) working outward
(laterally)
• http://cal.vet.upenn.edu/projects/mri_edl/anatomy/case1/case1.
htm
Anatomy of the Metacarpus
• Cannon (lg. metacarpal) and splint bones (sm.
Metacarpal)
• Similar to those in our hands
• Horses have a simple foot with only one digit (toe)
• The split bones do not support any weight
• “Splints” occur from trauma of the ligaments joining
the splint and cannon bones together, causing
inflammation
• http://cal.vet.upenn.edu/projects/mri_edl/anatomy/cas
e2/case2.htm
Anatomy of the Phalanges
• Horses have one digit (toe) on each limb
composed of 3 phalanges and 3 sesamoid
bones
• Named according to their position
• Long pastern (1st), short pastern (2nd), coffin
bone (3rd)
• http://cal.vet.upenn.edu/projects/mri_edl/anato
my/case5/case5.htm
Anatomy of the Hoof
• Coffin Bone: Major bone of the foot, supports the
weight of the horse
• Navicular Bone: Small wedge-shaped bone lies
under the back of the coffin bone
• Navicular Bursa: Fluid-filled sac which cushions
the navicular bone and deep digital flexor tendon
• Deep Digital Flexor Tendon: Crosses the
navicular bones and attaches to the underside of
the coffin bone
Anatomy of the Hoof
• Digital Cushion: Spongy structure above the frog
• Coronary Band: Outer band of tissue at the hairline,
from which the hoof grows
• Corium: The deep tissue beneath the coronay band,
which provides the horn
• Wall: hard outer shell of the hoof
• Bars: back of the wall; aid in absorbing shock and
allows it to expand under pressure
• Sensitive Laminate: lock the wall to interior of hoof,
have blood and nerve supply
Anatomy of the Hoof
• Periople: Outer layer of the hoof- keeps moisture in
• Sole: Ground surface of the hoof, inside the wall
• Frog: Wedge-shaped structure that lies between the
heels- helps to absorb shock
• Lateral cartilages: from the flexible bulbs of the heel,
aid in expansion of the foot
• http://cal.vet.upenn.edu/projects/mri_edl/anatomy/cas
e6/case6.htm