anatomy unit 4 skeletal system notes

bone

strong but not very flexible

Protect

Assisting in the movement of the body

Providing a framework and shape

Storing minerals

Producing red and white blood cells.

Cartilage

weaker but very flexible

Reducing friction at the joints

Support

Acting as shock absorbers

Maintaining the shape & flexibility of ears and nose

Articulating Cartilage

- on ends of the bone to protect bone from grinding together.

Spongy Bone

- lighter calcified webbing on inside of bones at either end

Compact Bone

hard and dense with a large calcified matrix

Periosteum

protective outer coating around the bone.

Endosteum

protective coating lines the inside of the medullary cavity.

Medullary Cavity

a cavity inside the body of the bone.

Bone Marrow

sits inside the Medullary cavity. There are two types.

Epiphyseal Line

a line left over from a growth plate/ epiphyseal plate

Red Marrow

creates red blood cells, white blood cells, and platelets.

At birth, all bone marrow is red. With age, more and more of it is converted to the yellow type; only around half of adult bone marrow is red.

Yellow Marrow

mainly made of fat (adipose) cells.

Osteocytes

mature bone cells, are found in tiny cavities within the bone matrix.

Osteoblasts

bone-forming cells

Osteoclasts

bone-destroying cells

Lacunae

hardened calcified bone matrix (rings) made by the osteocytes.

Haversian system

matrix plus central (Haversian) canals, brings blood vessels and nerves to all areas of the bone.

Intramembranous and Endochondral

Two different types of ossification (bone formation)

Intramembranous ossification

Formation of flat bones; the bone is formed from connective tissue rather than from cartilage.

Endochondral ossification

occurs in long bones and most of the rest of the bones in the body; it involves an initial hyaline cartilage model that continues to grow.

skeletal system functions

Support

Movement

Protection

Blood cell production

Calcium storage and endocrine regulation

Axial Skeleton

consists of just the bones of the skull, ribs, and vertebrae

Appendicular Skeleton

consists of the bones from the arms and legs, including the shoulders and hips.

Short bone

bones that are as wide as they are long.

Examples: tarsals and carpals.

Long bone

bones that are longer than they are wide.

Examples: Femur, fibula, tibia

Irregular bone

cannot be grouped as any other type of bone.

Examples: vertebræ, sacrum, coccyx, temporal, sphenoid, ethmoid, zygomatic, maxilla, mandible, palatine, inferior nasal concha, and hyoid.

Flat Bones

function is either extensive protection or the provision of broad surfaces for muscular attachment.

Examples: occipital, parietal, frontal, nasal, lacrimal, vomer, scapula, hip bone, sternum, and ribs.

Sesamoid

found in locations where a tendon passes over a joint, such as the hand, knee, and foot.

body, head, neck, process, spine, condyle, fissure, fossa, foramen

types of bone markings

Body

the main portion of the bone

Head

A large rounded projection that forms part of a joint at one end.

Neck

- located at the base of the "head" of the bone.

Process

raised area or projection

Spine

Similar to a crest but raised higher; a sharp, pointed, slender projection.

Condyle

Rounded bump or large rounded prominence.

Fissure

Long, crack-line hole for blood vessels and nerves

Fossa

a shallow depression

Foramen

large hole through a bone

adult vs baby skull

baby skull: more elongated, larger orbits relative to size of skull, very large sutures, no teeth

Fibrous, cartilaginous, synovial

main types of joints

Fibrous Joints

- the bones are united by fibrous tissue.

Cartilaginous Joints

the bone ends are connected by cartilage.

Synovial Joints

the articulating bone ends are separated by a joint cavity containing synovial fluid.

Plane Joint

in between the carpals of your wrist and the tarsals of ankles -- Glide across one another, provides a little bit of flexibility.

Hinge Joint

elbow (ulna and humerus), knee (tibia and the femur), ankle(tibia and talus)-- Bend/straighten a limb.

Pivot Joint

Elbow (radius and humerus), Neck (Axis(C2) and Atlas(C1)), Ankle (Fibula and Talus) -- Twist

Condyloid Joint-

Fingers (phalanges and metacarpals) and toes (phalanges and metatarsals) ---

Modified ball-in-socket (limited to 2 planes)

Saddle joint

Thumb (metacarpal and the carpal)-- rocking back-and-forth in two different directions.

Ball-in-socket joint

Shoulder (Scapula and humerus) and the hip (femur and hip bone)--

greatest amount of movement and flexibility, movement in 3 planes.

Oblique Fracture

an oblique fracture is generally caused by a slanted blow to the bone. Most frequently found in the long bones of the arm and leg.

Spiral Fracture (Torsion Fracture)

Tension is exerted upon one part of the bone, while compressive forces are exerted upon the other. When these forces have exceeded the limit tolerable by the bone, fracture occurs.

Transverse Fracture-

A transverse fracture, which is broken straight across the bone, is the result of a sharp, direct blow or may be a stress fracture caused, for example, by prolonged running.

Complex/Comminuted Fracture

a closed fracture in which the soft tissue surrounding the bone is severely damaged. Several bone fragments.

Displaced Fracture

fracture in which the two ends of the broken bone are separated from one another. (Any type of fracture can also be displaced.)

Open (Compound) Fracture

An open fracture is a broken bone that penetrates the skin. Open fractures are typically caused by high-energy injuries such as car crashes, falls, or sports injuries.

Reactive Phase , reparative phase, remodeling phase

Phases of healing

Reactive Phase

Fracture and inflammatory phase

Hematoma formation

Reparative Phase

Cartilage Callus formation

Bony callus of spongy bone

Remodeling Phase

Remodeling to original bone shape