4. Bones & Joints

Question 1

What are the functions of the skeleton?

Answer 1

Support
Protection
Movement
Mineral and growth factor storage
Heamatopoiesis

Question 2

What are the 3 regions in long bones?

Answer 2

Epiphysis
Metaphysis
Diaphysis

Question 3

Give an example of a short bone.

Answer 3

Carpal and tarsal bones

Question 4

What is the structure of short bones?

Answer 4

Mainly spongy bone
Thin layer of periosteum-covered compact bone on outside
No epiphysis or diaphysis

Question 5

Outline the blood supply of bones.

Answer 5

Nutrient artery - enters diaphysis via nutrient foramen
Periosteal arteries - supply periosteum and outer third of cortex
Metaphyseal arteries - enter metaphysics at site of attachment of capsule

Question 6

What are the 3 structural classifications of joints?

Answer 6

According to tissue between the bones:
Fibrous
Cartilaginous
Synovial

Question 7

Give an example of a fibrous joint.

Answer 7

Sutures of the skull

Inferior talofibular joint

Question 8

Give an example of a primary cartilaginous joint.

Answer 8

1st sternocostal joint

xiphisternal joint

Question 9

What is a primary cartilaginous joint characterised by?

Answer 9

United by hyaline cartilage

Question 10

What are secondary cartilaginous joints characterised by?

Answer 10

Articulating bones covered with hyaline cartilage with a pad of fibrocartilage between them

Question 11

Give examples of secondary cartilaginous joints.

Answer 11

Pubic symphysis, intervertebral disc, manubiosternal joint

Question 12

What is a synovial joint?

Answer 12

Joint cavity containing synovial fluid

Question 13

What are the characteristics of a synovial joint?

Answer 13

1. Articular cartilage overlying bones
2. Fibrous capsule enclosing joint - stabilises
3. Synovial membrane that produces synovial fluid

Question 14

What is the composition of synovial fluid?

Answer 14

Hyaluronic acid, lubricant, proteinase, collagenase

Question 15

What is the function of synovial fluid?

Answer 15

Reduces friction, shock absorption, nutrient and waste transportation

Question 16

Describe the blood supply of synovial joints.

Answer 16

Articular cartilage is avascular
Fibrous capsule and ligaments have poor blood supply
Synovial membrane has rich blood supply

Question 17

What are the types of synovial joint?

Answer 17

Ball and socket
Plane 
Saddle
Hinge
Pivot
Condyloid

Question 18

Where are planar joints found?

Answer 18

Intercarpal joint, sternoclavicular, acromioclavicular - no axis of movement

Question 19

Give an example of a hinge joint.

Answer 19

Knee, ankle, humeroulnar joint of elbow

Question 20

Give an example of a pivot joint.

Answer 20

Proximal radioulnar joint

Atlantoaxial joint

Question 21

Give an example of a condyloid joint.

Answer 21

Metacarpophalangeal joints

radiocarpal joints

Question 22

Give an example of a saddle joint.

Answer 22

1st carpometacarpal joint

Question 23

What factors affect stability and range of motion at synovial joints?

Answer 23

1. Structure/shape of articulating bones
2. Strength and tension of joint ligaments
3. Arrangement and tone of muscles
4. Hormones
5. Use/disuse

Question 24

What is the pathophysiology of RA?

Answer 24

Autoantibodies attack the synovium, causing inflammation.

Question 25

What is the effect of ageing on joints?

Answer 25

1. Decreased production of synovial fluid 2. Thinning of articular cartilage 3. Shortening of ligaments and decreased flexibility 4. Degenerative changes