Joints & connective tissue

Question 1

What are the main components of (most) connective tissue?

Answer 1

Cells

Ground substance

Collagen fibres

Question 2

3 types of joints

Answer 2

• Fibrous
• Cartilagenous
• Synovial

Question 3

Function of subchondral bone in synovial joints

Answer 3

• Forms joint surface, supports cartilage
• Distributes load to epi-, metaphyseal and cortical bone
• Rich blood, lymphatic, nerve supply –> must supply not only bone but the overlying cartilage too
• Maintains joint congruency

Question 4

What do we examine when looking at synovial fluid?

Answer 4

• Gross appearance
• Cytology
• Biochemistry
• Biomarkers (inflammation? matrix destruction? cytokines?)

Question 5

Where is synovial fluid produced?

Answer 5

At the synovial membrane

Question 6

Describe the characteristics of normal synovial fluid?

Answer 6

• Transparent
• Straw-coloured (pale yellow)
• Slippery
• Viscous

Question 7

What is the function of the joint capsule in a synovial joint?

Answer 7

• Support synovium
• Stabilise joint
• Contains nerves important for proprioception

Question 8

Describe the function of the collateral ligaments in a synovial joint?

Answer 8

• Provide stability between adjacent bones
• High elastin:collagen ratio enables stretch

Question 9

Describe the function of tendon sheaths

Answer 9

• Ease the passage of tendons around angles

Question 10

Describe the function of bursae

Answer 10

• Cushion and protect soft tissue passing over hard points

Question 11

What factors are important in normal joint homeostasis and why?

Answer 11

• Load-bearing (for subchondral bone)
• Normal forces i.e. even load bearing across joint surface
• Cartilage turnover
• Low concentration of cytokines
  
  • Peptide regulatory factors