Skeletal System

Functions of the skeletal system

Framework Support/protect internal organs Body movement

Provides leverage for lifting and movement through the attachment of muscles

Produced blood cells Red blood cells and some white blood cells

Stores the majority of the body’s calcium supply

Accessory Structures

Cartilage: On end surfaces to prevent friction

Ligaments Attaches bone to bone

Tendons Attaches muscle to bone

Axial skeleton

Consists of Skull Spinal column Ribs sternum

Appendicular skeleton

Upper extremities Shoulder girdle Lower extremities Pelvic girdle

Four groups of bone

Long Length is greater than

the width Femur

Short Blocky bones Similar length/width Wrist (carpal) and

ankle (tarsal ) bones

Four groups of bone

Flat Composed of two

layers with spongy bone between them

scapula and skull Irregular

Bones of complex shape and structure

Facial and vertebrae bones

Bones of the Skull

Cranium: encloses the brain (skull) Frontal

forehead Parietal

Roof and upper sides of cranium

Occipital Posterior floor and

walls of cranium Temporal

Sides and base of cranium

Bones of the Skull

Mandible Lower jaw bone Only moveable bone

Maxilla Upper jaw bone

Thorax

Rib cage Ribs Sternum Thoracic vertebra

True ribs Attached to sternum

False ribs Attached to ribs above

Floating ribs Attached to vertebrae

only

Spinal Column

Vertebral column 26 vertebrae

Types of vertebrae Cervical

neck Thoracic

Chest Lumbar

Lower back Largest and

strongest

Spinal Column

Sacrum Triangular shaped Base of spine

Coccyx Tail bone End of spine

Structures of the

Long Bone

Bone Tissue

Compact bone Hard dense part of

bone

Cancellous Loosely packed or

spongy

Structures of bones Long Bone Diaphysis

Long shaft of bone Epiphysis

Ends of long bone Medullary canal

Cavity w/in diaphysis Contains either yellow

or red marrow

Structures of bones

Tissues of a bone

Periosteum Outer covering of

bone Layer promote bone

growth (ossification) nutrition, and repair

Endosteum Lines medullary

canal

Structures of bones

Bone marrow Red bone marrow

Manufactures RBCs & WBCs

Ribs, sternum, vertebrae, scapula, ends of long bones

Yellow bone marrow Functions as fat

storage

Blood cells

Erythrocytes Carry O2 and CO2

Leukocytes Fight infection

Thrombocytes clotting

Joints

Articulation and Movement

Joints

Two or more bones join together Three types of joints:

Immovable (synarthrosis) Cranium

Slightly movable (amphiarthrosis) Pelvis

Freely movable (diarthrosis)

Freely Moveable Joints

Freely movable (Synovial) joints of the body Pivot joint

Allow rotation on single axis Base of skull

Ball and socket wide range of movement in many directions Hips and shoulders

Hinge joints Allows movement in one direction or plane (bend and

straighten) Knees and elbows

Freely Moveable Joints

Saddle joint Convex and

concave surface fit together

thumb Gliding joint

Two surfaces meet with motion limited by tissues and ligaments

Wrist and ankle

Synovial fluid

Lubrication for joints smooth movement of

joints Acts as shock absorber

Meniscus Fluid-filled disc Reduces friction

Bursa Sac lined with synovial

membrane Reduces friction

Disorders of the

Skeletal System

Disorders of the Skeletal System Osteomyelitis

Severe inflammation of bone and bone marrow, resulting form bacterial infection

Osteoporosis Bones that have calcium

and phosphorous deficiencies

Bones are very porous and fracture easily

Occurs in women as they age due to estrogen and other hormonal and mineral deficiencies

Disorders of the Skeletal System

Arthritis Inflammation of the

joint Bursitis

Inflammation of the bursa

Disorders of the Skeletal System

Gout Accumulation of uric

acid crystals in a joint Dislocation

Separation of a joint and the malposition of an extremity

Sprain Injury to the soft

tissues of a joint, characterized by the inability to move, deformity, and pain

Fractures

Fractures

Greenstick fracture Incomplete break that

occurs almost exclusively in children

Incomplete fracture Fracture lines does not

extend through bone or disrupt the entire thickness of bone

Complete fracture Fracture lines goes all

the way through bone

Fractures

Comminuted fractures Bone broken in several

places and splinters of bone can be embedded in surrounding tissue

Fractures

Compression fracture Bone collapses due to

disruption of bone tissue

Usually in vertebrae

Fractures

Compound: Causes disruption of

skin and soft tissue Fragment of bone

punctures skin Often complicated by

infection

Fracture treatment-Reduction

Manipulation to restore correct anatomical position

Fracture treatment-Reduction

Open reduction surgical incision to

expose fracture site Bone realigned and

position with internal fixation (rods, plates, screws)

Closed reduction Local or general

anesthesia may be used

Manipulate bone back into normal position

Fracture treatment-Immobilization

Immobilization with a cast or splint

Alleviates muscle spasm around fracture site

Fracture Treatment-Traction

Pin inserted through distal bone fragment and pulling forces helps return overriding fragments to normal anatomical position

Used until healing takes place or

Until internal fixation can be performed

The End