Anatomy and Physiology Chapter 9 Joints

arthrology

study of joints

fibrous joints

dense regular connective tissue

cartilaginous

cartilage being located at the joint

Synovial

type of membrane located at this joint, cavity at the articulation

diarthrosis

freely movable joints

example: synovial joints

amphiarthrosis

slightly moveable joints

example: syndesmosis and symphysis

synarthrosis

Immovable joints/doesn't move

example: sutures, synostosis (adults)

sutures

skull only

gomphoses

anchor teeth into sockets

syndesmoses

interosseous membrane.

interosseous membrane

sheet of collagen fibers that attach the shafts of two bones. between radius and ulna

cartilaginous joints

two bones bound together by cartilage.

synovial joint anatomy

the relationship between mobility and stability joints

stable(yet limited mobility)

suture

interosseous membrane

intervertebral joints

knee joint

glenohumeral joint

mobile(yet unstable)

Sternoclavicular joint

synovial joint, diarthrosis, 1st rib and sternum, sternocostal

types of synovial joints

ball and socket: multiaxial joints, shoulders and hips

hinge joints: monaxial, elbow, knee, interphalangeal joints

saddle joint: biaxial

pivot: monaxial

gliding: ampharthroses

condyloid: biaxial

flexion

decreases the angle of a joint. (bending elbow or wrist)

extension

straightens a joint and returns a body part to the anatomical position

hyperextension

extension of a joint beyond 180 degrees or over the anatomical position

dorsiflexion

raising of the toes as when you swing the foot forward to take a step (heel strike)

plantar flexion

extension of the foot so that the toes point downward as in standing on tiptoe

abduction

movement of a part away from the midsagittal line (midline)

Example: raising arm to the side, spreading finger

adduction

movement towards the midsagittal line

when does supination and pronation occur?

in the forearm and foot

supination

rotation of forearm so that the palm faces forward

pronation

rotation of forearm so the palm faces to the rear

elevation

movement that raises a bone vertically. mandibles are elevated during biting and clavicles during a shrug

depression

lowering the mandible or the shoulders

protraction

movement of a bone anteriorly (forward) on a horizontal plane. thrusting the jaw forward, shoulders or pelvis forward

retraction

movement of a bone posteriorly

what occurs during lateral and medial excursion?

Side to side grinding movements occurring during chewing

Lateral excursion

sideways movement to right or left

Medial excursion

Movement back to the midline

Opposition

Movement of the thumb to approach or touch the fingertips that allows you to grasp an object and hold on to it

Reposition

Movement back to the anatomical position

Inversion

Movement in which the soles are turned medially

Eversion

Turning the soles to face laterally

Synostosis

a joint formed by fusion of two bones and the boundary between them disappears

Synchondrosis

cartilage bridge between two articulating bones (immovable)

Gomphosis

dense connective tissue (fibrous joints)

Example: periodontal ligaments

Symphysis:

is a cartilaginous joint in which the ends of the articulating bones are covered with hyaline cartilage, but a broad, flat disc of fibrocartilage connect to the bones (slightly movable)

Synovial membrane releases:

synovial fluid into the joint cavity

Functions of synovial fluid:

a. lubrication

b. shock absorption

c. provide nutrients for the tissue in the joint

d. protect articular cartilage (because it contains phagoytes)

Characteristics of articular cartilage

a. hyaline cartilage

b. no perichondrium

c. surfaces are normal slick and smooth

d. the matrix contains more water than other cartilage

When articular cartilage is damaged (arthritis)

a. the cartilage matrix is to break down

b. the surface is rough

c. more friction occur

d. normal synovial joint function is unable to continue

Bursae

a. sac-like structures filled with a small amount of fluid that is similar to synovial fluid

Tendon sheaths

tube-like bursae

Bursea are situated to:

reduce friction in some joints

Bursea are found in:

the tendon sheaths, beneath the skin that covers vone, and most of synovial joints (shoulder, knee, elbow joints)

The stronger and more stable a joint...

the less mobility it has

The weaker and less stable a joint...

the more R.O.M. (range of motion) it has

Dislocation occurs when:

the articulating surfaces of a synovial joint are foced out of position

Types of movements that may be permitted at a synovial joint:

a. linear motion (gliding)

b. angular motions (flexion, extension, adduction, abduction, and circumduction)

c. rotation

d. other special movements (eversion, inversion, protraction, retraction, depression, elevation, opposition)

Examples of gliding joints include:

inter-carpals

inter-tarsals

vertebrae with ribs

clavicle with sternum

ilium with sacrum

Gliding join is:

biaxial or multiaxial

Hinge joint is:

angular, monoaxial

Condylar joint is:

angular, biaxial

Examples of condylar joints

a. radiocarpal joint

b. medacarpophalangeal joints 2-5

c. metatarsophalangeal joint

Pivot joint is:

rotaion, monoaxial

Examples of pivot joints

a. Atlanto axial joint

b. proximal radio-ulnar joints

Ball and socket joint is:

angular, circumduction, rotation, tri-axial (multi-axial)

Example of a hinge joints

a. The articulation between tibia and talus bone (ankle joint)

b. elbow joint

c. interphalangeal joint

Examples of ball and socket joints:

a. shoulder joint

b. hip joint

Examples of saddle joint

a. the joint between carpal (trapezium bone) and metacarpal I (thumb)

The joint that permits the greatest ROM (Range of motion) is the:

shoulder joint

The should joint is mainly stabilized by:

a group of muscles (rotator cuff muscles) that move the humerus bone and reinforce the joint capsule

Baseball pitchers are the greatest risk of developing:

rotator cuff injury

The most common athletic knee injuries involve:

menisci

In the elbow joint the largest and strongest joint is the:

articulation between the humerus and the ulnar bone (humero-ulnar joint)

The elbow joint is mainly stabilized by:

a strong and thick articular capsule

Functions of the intervertebral discs:

a. act as shock absorber

b. prevent bone-to-bone contact

c. contribute the height of the individual

d. allow the movements associated with flexion, extention and rotation of the spine

A hernia disc is cause by:

protrusion of the nucleus pulposus of the intervertebral disc

The role of the menisci (medial and lateral menisci) is to:

act as cushions and conform to the shape of the articular cartilage

The menisci are responsible for:

channeling the flow of synovial fluid in the knee joint

Knee joint is a:

modified hinge joint that consists of three articulations within a single cavity

Compared to the should joint, the complete dislocation of the knee joint is rare because:

the knee joint is stabilized by 7 major ligaments

Compared with that of the shoulder, the articular capsule of the hip is very:

dense and strong

Compare with that of the hip, the articular capsule of the knee is:

weak

Five ligaments of the hip joint include;

1. iliofemoral

2. pubofemotal

3. ischiofemoral

4. ligament teres (ligaments of the head of femur)

5. transverse ligament of the acetabulum

Seven ligaments of the knee joint include:

1. patellar ligament

2. popliteal ligament (2)

3. ACL

4. PLC

5. Tibial collateral

6. Fibular collateral

The ACL and PCL:

a. limit the anterior and posterior movement of the tibia

b. maintain the alignment of the femoral and tibial condyles

The structure that assists the bursae in reducing friction between the patella and other tissues are:

FAT PADS

When the articular cartilage is damaged:

a. the matrix begins to break down

b. the expose articular surface become rough

c. the friction of the joint increases

d. normal synovial joint functions is unable to continue

Rheumatism is a general term for:

pain and stiffness affecting the musculoskeletal system

Arthritis affects the:

synovial joints