Chapter 8: Joints

What are the functions of joints?

stability by binding parts of skeletal system

bone growth

change shape childbirth

movement for skeletal muscle contraction

True or false: the number of joints changes in the human body from birth to old age?

true

How many joints are there in the human body?

203

What do joints vary in?

function and structure

Functionally joints are classified according to?

degree of movement they make possible

Immovable joints are considered?

synarthrotic

Slightly moveable joints are considered?

amphiarthrortic

Freely moveable joints are considered?

diarthrotic

Some diarthrotic joints movement can occur over distances such as?

flexion and extension of the elbow

The joint between the sacrum and ilium can move freely but only for?

short distance

Joints are classified?

by the type of tissue that binds the bones at each junction

What are the three general groups of joints?

fibrous, cartilagenous, synovial

Fibrous joints are?

two or more bones joined together by dense connective tissue (includes collagen fibers)

Where are fibrous joints found?

between bones in close contact

What are the three types of fibrous joints?

syndesmoses, sutures, gomphoses

Syndesmosis is a?

type of joint in which bundles of connective tissue unite bones

In syndesmosis the bones are bound by a sheet and dense connectvie tissue called?

interosseous membrane and interosseous ligament

Syndesmosis is somewhat flexible and can be twisted so it is functionally classified as?

amphiarthrotic joint

Where is a syndesmosis located?

between the tibia and fibula at the distal end and diaphysis

Where is a suture found only?

between flat bones of the skull

Sutures are immovable making them classified as?

synarthrotic joints

What is the function for fontanels?

allow fetal skull to change shape during childbirth

Gomphosis is formed by?

the joining of a cone shaped bony process in a bony socket

True or false gomphosis is synarthrotic (permitting no movement)

true

Hyaline cartilage or fibrocartilage connects the bones of?

cartilagenous joints

What are the two types of cartilagenous joints?

synchondroses and sympheses

A synchondrosis involves bands of?

hyaline cartilage joining bones

Synchondrosis is classified as?

synarthrotic

In symphysis the bones are connected by?

a pad of fibrocartilage and the bone surface is lined with hyaline cartilage

Symphisis is classified as what?

amphiarthrotic

What is the function of intervertebral disc?

absorb shock and equalizes pressure between the vertebrae when the body moves

Many of the joints in synchondrosis are temporary structures that later?

disapear during growth

What is an example of where synchondrosis lies?

between the manubrium of the sternum and the first rib

What is an example of where symphysis is located?

pubic symphysis between the pubic bones of the pelvis

Most joints of the skeletal system are?

synovial joints

Synovial joints are classified as?

diarohrotic joints

Synovial joints are more complex structurally than?

fibrous and cartilaginous joints

What does a synovial joint consist of?

articular cartilage, joint capsule, and synovial membrane (secretes fluid)

Articular cartilage functions as?

resists wear and minimizes friction when it is compressed as the joint moves

A joint capsule is strengthened by?

ligaments that holds bones together

A synovial membrane that secretes synovial fluid lines?

the inner layer of a joint capsule

Synovial fluid functions include:

moistens, proides nutrients, and lubricates the articular surfaces

Menisci divide some synovial joints into?

compartments

Some synovial joints have a fluid filled called?

bursae

Most bursae is located between the?

skin and underlying bony prominences

Bursae cushion and aid movements of?

tendons over bony parts

How are bursae named?

according to their locations

What are the six major types of synovial joints?

ball and socket

condylar

plane

hinge

pivot

saddle

In a ball and socket joint the globular head of a bone fits into what?

cup shaped cavity of another bone

What is an example of a ball and socket joint?

hip and shoulder

A condylar joint consists of an ovoid condyle of one bone that fits into?

elliptical cavity of another bone

True or false: a condylar joint permits movement into two planes

true

What is an example of a condylar joint?

the joints betwen the metacarpals and phalanges

Articular surfaces of plane joints are?

nearly flat

Plane joints permit the articular surfaces to?

slide back and forth

Most of the joints of the wrist and ankle are?

plane joints

In a hinge joint the convex surface of one bone fits into the?

concave surface of another bone

Hinge joint permits movement in?

one plane only

What is an example of a hinge joint?

elbow and fingers

In a pivot joint a cylindrical surface of one bone rotates within a?

ring of bone and ligament

Pivot joint permits?

rotational movement

What is an example of a pivot joint?

articulation between the proximal ends of the radius and ulna

A saddle joint forms between?

bones that have complementary surfaces with both concave and convex regions

Saddle joints permit a?

variety of movements

What is an example of a saddle joint?

the articulation between the carpal and metacarpal of the thumb

Muscles acting at synovial joints produce movements in?

directions and in different planes

Joint movements include:

flexion, extension, dorsiflexion, plantar flexion, abduction, adduction, rotation, circumduction, supination, pronation, eversion, inversion, protraction, retraction, elevation, and depression

Examples of synovial joints:

jaw, shoulder, elbow, hip, knee

The jaw joint consists of?

mandibular condyle of the mandible and the mandibular fossa of the temporal bone

The jaw joint is a modified hinge joints that permits?

depression and elevation of the mandible as well as protraction and lateral gliding movements

The shoulder joint is a ball and socket that consists of?

head of the humerus and the glenoid cavity of scapula

Parts of the shoulder joint are loosely attached so the shoulder joint permits?

a wide range of movements

The elbow has a hinge joint between the?

humerus and the ulna and a plane joint btwn the humerus and radius

The joint between the humerus and the ulna permits?

flexion and extension only

The hip joint is a ball and socket joint between?

femur and the hip bone

In a hip joint a ring of fibrocartilage deepens the cavity of the?

acetabulum

The articular surfaces of a hip joint are held together by a?

heavy joint capsule reinforced by ligaments

The hip joint permis a?

wide variety of movements

The knee joint includes a modified hinge joint between the?

femur and the tibia and a plane joint between the femus and patella

The knee joint permits flexion and extension:

when the knee is flexed some lower limb rotation is possible

Joint stiffness is often the earliest sign of?

aging

Collagen changes the feeling of?

stiffness

Fibrous joints are the first to begin to?

change and strengthen over a lifetime

Synchondroses of the long bone disapears with?

growth and developement

Changes in symphysis joints of the vertebral column diminish?

flexibility and decrease height

Over time synovial joints lose?

elasticity