A+P Bones/Joints Test

How many bones are in the adult skeleton?

206 bones

Divided into 2 parts - Axial Skeleton (Skull, Vertebral Column, Rib Cage), Appendicular Skeleton (Bones of arms and legs, bones of shoulder, pelvis)

5 functions of the Skeletal System

Support - skeleton enables bodies to stand up

Protection - skull protects the brain: vertebrae protect the spinal cord; rib cage protects the heart and lungs

Movement - Skeletal muscles are attached to bones when muscles contract, the bones produce movement

Storage - bones store and release minerals (calcium & phosphorus) and fat

Blood Cell Formation - Hematopoesis - to make blood

What does Hematopoiesis mean

to make blood

How are bones classified according to shape

Long Bones, Short Bones, Flat bones, Irregular Bones, Sesamoid Bones

Long Bones

typically longer than wide

have shaft with heads at both ends

mostly compact bone

help support body weight and facilitate movement

examples: Humerus, raidus, ulna, femur, tibia, fibula, clavicle, metacarpals, metatarsals, phalanges

Short Bones

Generally cube shape

Contain mostly spongy bone

provide stability and some movement

Examples: carpals and tarsals

Flat Bone

thin, flattened, curved

provide protection & large areas for attachment of muscle

thin layers of compact bone around a layer of spongy bone

Examples: occipital, frontal, & parietal; scapula; the ribs, sternum, illium

Irregular Bone

Irregular Shape

Don’t fit into other bone classification categories

Examples: Vertebrae, sacrum, sphenoid & ethrnoid bones

Sesamoid bone

tiny bone

embedded in a tendon or muscle - aid in movement

provides a smooth surface for tendons to move on

Examples: Patella (knee cap) , few bones in hands and feet - bone inside a tendon where a tendon covers a joint. special type of short bone.

Osteocyte

mature bone cells

Osteoblast

bone-forming cells for bone growth

Osteclasts

Bone destroying cells that break done bone matrix for remodeling and release of calcium

Label parts of the long bone

Quizlet found on classroom

Ossification

Bone growth

Epiphyseal Plates (growth plates)

Bones are remodeled and lengthened until growth stops

Bones change shape, grow in width

Lengthening stops and the epiphyseal plate changes into epiphyseal line

Bone remodeling

After longitudinal growth stops, bones continue to grow thicker and wider and continuously reshape throughout your life

osteoblasts and osteoclasts work together

Open Fracture (compound)

fractures where the bone pierces the skin

Closed Fracture (Simple)

fracture where the bone stays under the skin and doesn’t break it

Complete fracture

fracture where pieces of bone completely separate

Incomplete fracture

fracture where the pieces of the bone do not separate, involve partially separated fragments

Comminuted fracture

fracture that invovles many fragments

Spiral Fracture

bone fracture caused by a twisting force, also called torsion fracture

Greenstick fracture

fracture in which only one side of the bone is broken, bone usually has a bend to it and fracture is located at the outside of the bend, common in young children

Avulsion Fracture

occurs when a small chunk of bone attached to a tendon or ligament gets pulled away from the main part of the bone

Harline Fracture (Stress fracture, transverse, oblique)

incomplete fracture which the crack is only in the outer bone later, also called a fissure fracture and linear fracture

Transverse Fracture

fracture straight across the bone, usually the result of sharp, direct blows; the break occurs at a right angle to the bone’s long axis

Oblique fracture

fracture diagonal to bone’s long axis

4 steps to how a bone heals after a fracture

1. Hematoma 6-8 hrs - blood filled swelling is formed
2. 3 weeks - break is immobilized by fibrocartilage callus
3. 3-4 months - fibrocartilage callus is replaced by bony callus
4. bony callus is remodeled to form a permanent patch

Synarthortic Joint

No movement (immobile)

provides a strong connection between the adjacent bones

protects internal organs

fibrous joint

Fibrous connective tissue grows between articulating bones

Example: sutures of the skull

Amphiarthrotic Joint

Slight movement (Limited Mobility)

cartilage connects articulating bones

Strongly anchor bones together, but allows for movement

made of fibrocartilage

Example: pubic symphsis

Cartilaginous joint

Diarthortic Joint (Synovial Joint)

surrounded by joint capsule lined with synovial membrane and filled with synovial fluid

supporting ligaments join bones and stabilize joint

some have extra cartilage inside the capsule (meniscus or articular disc)

Bursae

small sacs of synovial fluid between joint & tendons which allow tendons to slide as joints move.

Synovial Joint

See Slides

Ball and Socket Joints

Most mobile joints in the body; various directions

B & S joints are more susceptible to displacement, tearing of ligaments, tendons, or cartilage 

Form when ball-shaped end of bone fits into cup-shaped socket of another

Most easily injured

Examples:  hip & shoulders

**Condyloid Joints**

Allow for up-and-down and side-to-side movement

Form when oval-shaped end of bone fits into oval socket

Examples: knuckles between metacarpals & proximal phalanges.  (Fingers move up & down and can spread out)

**Saddle Joints**

Only 1 set in the body!

Between the metacarpal bone of the thumb & a carpal bone of the wrist.

Allow for great mobility

**Hinge Joints**

Allow movement in one direction

Only bending and straightening

Examples:  Elbows, knees

**Plane (or Gliding) Joints**

Articulating surfaces are flat & about same size.

Motion is usually small & tightly constrained by ligaments  (least mobile of all joints)

Between the carpal & tarsal bones (wrist & ankle), and between vertebrae

**Pivot Joints**

Rounded portion of bone is nestled into another bone and held in place with a ligament.

Only allows for rotation (or twisting)

Examples:  C1 & C2 vertebrae (shaking head to say no), the proximal end of the radius & ulna (elbow) which allows you to flip your hand over

**Flexion**

Bending of the joint that decreases the angle between the bones.

**Plantar Flexion**

pointing the toe (decreasing angle between calcaneus & tibia)

**Dorsiflexion**

bending the foot upward toward leg or “flexing the foot” (decreasing angle between metatarsals & tibia)

**Extension**

Straightening so the angle between joints increases

**Hyperextension**

overextending the joint beyond its normally straightened position

**Adduction**

Movement TOWARD the midline of the body.

**Abduction**

Movement AWAY from the midline of the body

**Eversion**

Turning the sole of the foot outward.

**Inversion**

Turning the sole of the foot inward so it faces the opposite foot.

**Supination**

Turning he hand so the palm faces upward.

**Pronation**

Turning the hand so the palm faces downward

**Circumduction**

Movement in a circular rotation

**ACL**

prevents forward movement of tibia from under the femur

**PCL**

prevents tibia from moving too far backward under the femur

**MCL**

joins medial aspects of femur & tibia; resists forces from the lateral side of knee

**LCL**

connects lateral side of femur & fibulia; holds lateral side of knee together

**Menisci**

crescent-shaped pads of cartilage between femur & tibia that act as shock absorbers

Which meniscus gets injured more?

***Medial meniscus*** *is more susceptible*

**Osteoarthritis**

Degenerative Arthritis”

Results from degeneration of articular cartilage; most common form

**Rheumatoid Arthritis**

Rheumatism”

Results from inflammation of the synovial membrane; most debilitating & chronic type

**Sprains**

Joint injury caused by twisting

Causes pain, loss of mobility, swelling & black-blue discoloration of injured area

Ligaments may be torn, but no bone or joint damage has occured

**Strains**

Injury to the muscle or tendon at a joint

Caused by overuse or overstretching

Less serious than a sprain