Meat and Bones

William Sweetman

Skeletal SystemConsists of bones, cartilage, joints, ligaments,

and tendons Made of connective tissuesConnective Tissue

Type of tissue in which the proportion of cells to extracellular matrix is small

BoneA form of connective tissue, is one of the

hardest tissues in the body

Ossification

The formation of bones from fibrous tissues, continues until maturity

Bone growth is balanced between the actions of osteoblasts and osteoclats Osteoblasts: immature bone cells that produce

bony tissue Osteoclats: are phagocyte cells that eat away

bone tissue from the medullary cavity of the bone

When osteoblasts mature they become osteocytes

Red bone marrow, located in cancellous bone, is hematopoietic◦ Produces red blood cells, white blood cells, and

clotting cells◦ The medullary cavity of bone, or inner space of

bone, contains yellow bone marrow In adult animals, yellow bone marrow replaces red

marrow

Ossification

CartilageAnother form of connective tissue more

elastic than boneArticular cartilage

Covers the joint surfaces of boneMeniscus

A curved fibrous cartilage found in some joints that cushions force applied to joints

Joints

Connections between bones Classifications

› Synarthroeses: allow no movement› Amphiarthroses: allow slight movement› Diarthroses: allow free movement

Suture: a jagged line where bones join and form a non-movable joint

JOINTS

Fontanelle: a soft spot remaining at a junction of sutures that usually close at birth

Symphysis: a joint where two bones join and are held firmly together so they form a junction

Ball-and-sock joints: a wide range of motions in many directions

Ligaments and Tendons Ligaments: a band of fibrous

connective tissue that connect bones Tendons: A band of fibrous connective

tissues that connect muscle to bones Brusa: a fibrous sac that acts as a

cushion to ease movement in areas of friction

Synovial Membrane and Fluid Synovial Membrane: the inner lining of

Bursae and synovial jointsSecretes synovial fluid which acts as a

lubricant to make joint movement smooth

Axial and Appendicular Skeleton Axial

The frame work of the body Appendicular

Consists of extremities, shoulder, pelvic griddle, and cranium

Vertebral Colum Supports the head and body, and protects

the spinal cord

BODY

Solid portion ventral to the spinal cord; midline portion

Arch The dorsal part of the vertebrae that surrounds

the spinal cord Lamina: the left or right dorsal halves of the

arch Spinous process: a single projection from the

dorsal part of the vertebral arch

Transverse and Articular process Transversal process: project laterally from the

right and left sides of the vertebral arch Articular process: are paired cranial and

caudal projections located on the dorsum of the vertebral arch

Vertebral foramen: an opening in the midline of the vertebra through which the spinal cord passes through

Bone classificationsRibs: paired bones attached to

the thoracic vertebra Sternum: the breastbone, forms

midline ventral portion of rib cageManubrium: the cranial portionXiphoid: the caudal portionThoracic cavity: protects hearts

and lungs

Bone classifications

Scapula: the shoulder bladesClavicle: the collarboneHumorous: the long bone of the proximal

limbRadius: the cranial bone of the front limbUlna: the caudal bone of the front limbOlecranon: proximal projection found in the

ulna

Carpal bones: irregular shaped in the area known as the wrist

Metacarpals; bones found distal to the carpals

Splint bones: in horses metacarpals 2 and 4 do not articulate with the phalanges

Interosseous: splint bones attached by ligaments to the large third metacarpal (cannon bone)

Bone classifications

Bone classifications

•Phalanges: the bones of the digits•Digit: bones analogous to the human

figure•Sesamoid bones: small nodular bones

embedded in a tendon or joint capsule•Femur: the proximal long bone of the rear•Patella: a large sesamoid bone in the rear

limb•Tibia: the larger and more weight bearing

bone

Bone classifications

• Fibula: a long slender bone• Ambulation: a type of movement involving

running, walking, or moving from one place to another

• Fascia: a sheet of fibrous connective tissue that covers, supports, and separates muscles

• Linea alba: a fibrous band of connective tissue on the ventral abdominal wall

Pelvis

Three main parts; the hip Ilium: the largest pair, blade shaped Ischiam: the caudal part of the bones Pubis: the ventral pair of bones that are

fused on the midline by a cartilaginous joint

Acetabalum: the largest socket of the pelvic bone that forms where the 3 bones meet

Ranges of MotionAbductor: muscle that moves away from

midlineAdductor: muscle moves towards midlineFlexor: muscle that bends at its jointExtensor: muscle that straightensLevator: muscle that risesRotator: muscle that rotates

Ranges of Motion

Depressor: muscle that lowers Supinator: muscle that rotates Pronator: muscle that rotates

Pectoral: chest Epaxial: pelvic axis Intercostal: between the ribs Infraspinatus: located beneath the spine of

the scapula Supraspinatus: located above the spine of

the scapula Orbicularis: muscles surrounding another

structure

Muscles and locations