Chapter 9 - Joints

Question 1

Joints

Answer 1

where 2 or more bones meet so movement can occur

Question 2

3 Types of Joints

Answer 2

1. Fibrous joints - fibers; dense CT; mainly collagen
2. Cartilaginous joints - made of cartilage
3. Synovial joints - fluid filled cavity between 2 bones; allows for a lot of movement; most common joint in body

Question 3

Types/Functional/Examples of Fibrous joints

Answer 3

1. Sutures/Synarthrosis/Sutures of skull
2. Syndesmosis/Synarthrosis/ligaments
3. Gomphosis/Synarthrosis/Periodontal ligaments

Question 4

Types/Functional/Examples of Cartilaginous joints

Answer 4

1. Synchondrosis (made of hyaline cart) /Synarthrosis/epiphyseal plate & costal cartilages
2. Symphysis (made of fibrocartilage) /Amphiarthrosis/Intervertebral discs & pubic symphysis

Question 5

Types/Functional/Examples of Synovial joints

Answer 5

Diarthrosis/knees, elbow & shoulders

Question 6

Functional Classes of Joints

Answer 6

S - Synarthrosis - immovable joint
A - Amphiarthrosis - slightly movable joint
D - Diarthrosis - freely movable joint

Question 7

Examples of Synovial Joints based on shape of articular surface

Answer 7

1. Ball & socket joint - head of femur & acetabulum of coxal bone; very stable joint
2. Hinge joint - trochlea of humerus & trochlear notch of ulna; pretty stable
3. Pivot joint - head of radius & radial notch on ulna; not as stable; allows bone to rotatate along surface of another bone

Question 8

Bursae (definition & function)

Answer 8

flattened fibrous sacs lined w/synovial membrane & contains synovial fluid; designed to be like a ball-bearing;
function: minimize damage due to friction

Question 9

Structure of synovial joint

Answer 9

• Synovial cavity
• Articular cartilage
• Synovial membrane
• Fibrous capsule
• Reinforcing ligaments

Question 10

Synovial cavity

Answer 10

filled w/synovial fluid; lubricating fluid to allow for friction free movement

Question 11

Articular cartilage

Answer 11

covers end of bones @ a joint

Question 12

Synovial membrane & Articular cartilage

Answer 12

forms a cavity

Question 13

Fibrous capsule (stabilizing factors)

Answer 13

made of dense CT; covers outside of synovial membrane; makes it stronger; perostium

Question 14

Reinforcing ligaments (stabilizing factors)

Answer 14

attach bone to bone; binding material; helps to hold joints together

Question 15

Factors stabilizing synovial joints

Answer 15

1. shape of articular surfaces
2. ligaments - dense regular CT that attaches bone to bone
3. muscle tone - low level of contractile activity in relaxed muscle; most important; slight pull exerted on muscles @ all time that keeps bone in place

Question 16

Tendon Sheath

Answer 16

elongated bursa wrapped around a tendon; covers & protects tendon

Question 17

Found in some Synovial joints to minimize damage due to friction:

Answer 17

• Bursae

- Tendon sheath

Question 18

3 Most common types of arthritis (Joint diseases)

Answer 18

1. osteoarthritis
2. rheumatoid arthritis
3. gouty arthritis

Question 19

Arthritis

Answer 19

common symptoms with different causes

Question 20

Rheumatoid arthritis

Answer 20

autoimmune disorder, initially caused by inflammation of the synovial membrane

Question 21

Gouty arthritis

Answer 21

caused by uric acid accumulation

Question 22

Osteoarthritis

Answer 22

chronic degenerative disease mainly due to wear & tear on joints; “old-age disorder”; most common joint disorder

Question 23

Symptoms of Arthritis

Answer 23

• pain upon movement of joint
• swelling @ joint
• stiffness @ joint

Question 24

Autoimmune disorder

Answer 24

when immune system starts attacking own body

Question 25

Uric Acid

Answer 25

by product of metabolism; when too much in body, it forms crystals in joints (ex. base of big toe)