JOINTS

Question 1

What is a joint?

Answer 1

A place where two or more bones come together. Joints link bones together to form the skeleton.

Question 2

what do joints do?

Answer 2

Joints provide varying degrees of mobility and stability.
EG. the hip joint is very stable as it carries the weight of the body when we walk or run. In comparison the shoulder joint has more mobility allowing greater range of movement but has less stability.

Question 3

Common 6 key joints to move our limbs are:

Answer 3

1. shoulder
2. elbow
3. wrists
4. hip
5. Knee
6. ankle

Question 4

What type of joints are there?

Answer 4

1. fibrous
2. Cartilaginous
3. synovial

Question 5

Fibrous joints are..

Answer 5

The bones united together by fibrous tissue, They allow no movement at all.
eg. structures in the skull and the joints that joint the pelvic bones.

Question 6

Cartilaginous joints are..

Answer 6

The bones are united by cartilage and These joints allow small amount of movement
eg. the sternocostal joint between the sternum and the first rib and the joint of two pubic bones at the front of the pelvis. These joints allow small amount of movement

Question 7

Synovial joints are..

Answer 7

The bones meet in a joint capsule These joints are the most common and most moveable joints. They have several characteristics that allow extra mobility

eg. the knee joint here the femur and tibia meet.

Question 8

1. Characteristics of synovial joints are..Articular (hyaline) cartilage:

Answer 8

Articular (hyaline) cartilage: This is smooth, white, shiny mass that covers joining surfaces of the bone. Protect bone tissue and reduces friction between bones when they more

Question 9

2.Characteristics of synovial joints are..Articular capsule:

Answer 9

Attaches to the bone near the edge of the joining surfaces. It is made of strong fibrous tissue and surrounds the joint. Provides stability and stops unwanted material from entering the joint. Provides a cavity for synovial fluid to work within.

Question 10

3. Characteristics of synovial joints are..Synovial fluid:

Answer 10

Yellowish oily fluid lubes the surrounding surfaces and forms a fluid cushion between surfaces that provides nutrients for the cartilage and absorbs debris produce by friction between articulating joints

Question 11

4. Characteristics of synovial joints are..Ligaments

Answer 11

These are strong fibrous bands that unite articular surfaces, control movement and providing stability.

Question 12

5. Characteristics of synovial joints are.. Articular discs ( meniscus)

Answer 12

Articular discs ( meniscus) Some synovial joints like the knee are menisci, which are made of tough fibrous tissue. Their job is to absorb shock and main joint stability. They lie between articulating surcease and therefore protect the surfaces of articulating bone.

Question 13

6. Characteristics of synovial joints are..Bursae:

Answer 13

These are found in some SJ, They are closed sacs with Synovial fluid. Their role is to reduce friction that can occur with movement, such as when tendons rub over bones.

Question 14

Types of synovial joints

1. Gliding joints: aka plane joints.

Answer 14

1. Gliding joints: aka plane joints.
   The surfaces are flat and are of similar length. Movement occurs in a gliding or sliding of one bone against another. SIDE TO SIDE and BACK AND FOURTH is movement allowed in these joints.
   eg. Acromioclavicular (AC) joint in the shoulder, the sacroiliac (SI) joint where the sacrum joints the ilium, between the carpals, between the tarsals and between the ribs and vertebrae.

Question 15

Types of synovial joints

2.Saddle joint:

Answer 15

Saddle joint:

Allow side to side and back and fourth movements. eg. Thumb joint, between a carpal (trapezium) and metacarpal

Question 16

Types of synovial joints

3.Hinge joints:

Answer 16

Hinge joints:
Joint surfaces are arranged to allow only back and fourth movement such as bending or straightening.
Eg. Elbow where hummerus and ulna join. And the knee and the finger joints

Question 17

Types of synovial joints

4. Pivot joints:

Answer 17

Pivot joints:
Only allow rotation of one bone on or around another.
eg. the joint between the atlas and axis vertebrae, the rotation around each other allows our heads to pivot left and right. Also just below the elbow joint where the radius rotates on the ulnae allowing us to pivot our hand so palm faces up or down.

Question 18

Types of synovial joints

5. Ball and socket joints

Answer 18

Ball and socket joints:
Allows side to side, back and fourth and rotational movement.
eg. hip and shoulder joints

Question 19

Types of synovial joints

6. Ellipsoid joints (Condyloid)

Answer 19

Ellipsoid joints (Condyloid) Allow back and fourth, side to side, do not allow rotation. 
eg. carpals and the radius  and between the metacarpal and the phalange. Why does

Question 20

Movements that occur at synovial joints- Flexion:

Answer 20

Where the angle between two bones decreases. BENDING- happens at the trunk, elbow, shoulder, hip moving thighs forward, knee bending the leg.
Can occur on the horizontal plane at the shoulder is called horizontal flexion.

Question 21

Movements that occur at synovial joints- Extension:

Answer 21

Where the angle between two bones increases. Extension is also know as STRAIGHTENING- happens at the trunk, arm, shoulder knee, and hip.
Extensions occur on the horizontal plane at the shoulder and the hip is called horizontal extension.

Question 22

Horizontal flexion:

Answer 22

Movement where the angle between two bones decreases and occurs at the shoulder and hip on the horizontal plane. EG. Upward phase of a bench press or press up.

Question 23

Horizontal extension:

Answer 23

Movement where the angle is between two bones increases and occurs at the shoulder and hip on the horizontal plane. An example of horizontal extension at the shoulder is during the downward phase of a bench press or press up

Question 24

Plantar flexion is..

Answer 24

Moving the top of the foot away from the shin or pointing the toes

Question 25

Dorsiflexion is..

Answer 25

Moving the top of the foot toward the shin or raising the toes

Question 26

Abduction is..

Answer 26

Movement of a body segment away from the midline of the body. Raising the arm or leg out to the side away from the body is abducting.

Question 27

Adduction is..

Answer 27

movement of a body segment toward the midline of the body. If we adducted our arm or leg we would be bringing them toward our body from a position where they were out to the side.

Question 28

Supination is..

Answer 28

Movement of the forearm so the palm of the hand faces up or forward.

Question 29

Pronation is..

Answer 29

Movement of the forearm so the palm of the hand faces down or backward

Question 30

Eversion is..

Answer 30

Movement of the sole of the foot outward at the ankle.

Question 31

Inversion is..

Answer 31

Movement of the foot to bring the sole of the foot face inward at the ankle

Question 32

Circumduction is..

Answer 32

Movement where the joint is the pivot and the body segment moves in a combination of flexion, extension, adduction and abduction.

Question 33

Rotation is..

Answer 33

Movement of pivoting or rotating about the longitudinal axis of a bone

Question 34

Medial rotation is..

Answer 34

Movement of a body segment about the longitudinal axis, where the front of the segment rotates medially toward the midline of the body.

Question 35

Lateral rotation is..

Answer 35

Movement of a body segment about the longitudinal axis, where the front segment rotates laterally away from the midline of the body.

Question 36

Protraction/ Retraction is..

Answer 36

The forward movement of the scapula that results in hinting of the shoulders is termed as protraction. The opposite movement, pulling the scapula backwards to square the shoulders ist termed as retraction.

Question 37

Elevation/depression is..

Answer 37

The rising of the scapula to a more superior level (shrugging the shoulders) is termed as elevation. The opposite movement of elevation is termed as depression and involves pulling the scapula to a more inferior position.