Joints

Question 1

What are the normal structural components of a synovial joint?

Answer 1

-Articular cartilage
-Synovial membrane
-Synovial fluid
-Synovium
-Tendon
-Ligament
-Fibrous joint capsule

Question 2

What are the functions of the articular cartilage?

Answer 2

-Allow frictionless motion between joint surfaces
-Distrubution of joint load
-Dissipates energy associated with loading
-Aneural: Avascular: Alymphatic: Hypocellular

Question 3

What is the function of tendons?

Answer 3

Join muscle to bone enabling movement

Question 4

What is the function of ligaments?

Answer 4

Join bone to bone

Question 5

Describe the articular cartilage

Answer 5

-Contain chondrocytes
-Low turn over
-Made of extracellular matrix (water, collagen, proteoglycans) chondrocytes synthesise these components and maintain this.

Question 6

Describe the synovial membrane /lining

Answer 6

-Contains macrophages A cells (phagocytes) become activated when there is an inflamed joint = remove waste
-Contains fibroplasts B cells = produce hyaluronic acid

Question 7

Where in a joint has or hasn’t got a vascular, lymphatic or nerve supply within it?

Answer 7

Every joint has a vascular and nerve supply, but there is no lymphatic supply in the cartilage of the joint

Question 8

Define what is meant by cartilage homeostasis

Answer 8

Stable state and maintenance of the synovium and cartilage matrix in and out of the blood stream

Question 9

What is meant by negative intra-articular pressure?

Answer 9

Pressure in the synovial fluid increases and decreases, a passive stabiliser so it is maintained.

Question 10

What are the normal changes which occur at a joint with age?

Answer 10

-Joint movement becomes stiffer due to less synovial fluid and hyaluronic acid being formed to lubricate the articular cartilage
-Structure and thickness of the articular cartilage due to friction from loads and movement of ligaments and tendons (may shorten)

Question 11

What are the bony landmarks found at the knee?

Answer 11

-Lateral Collateral
-Medial Collateral
-Posterior Cruciate
-Anterior Cruciate

Question 12

What ligaments are found at the knee?

Answer 12

-LCL
-MCL
-ACL
-PCL

Question 13

What is the function of the MCL ligament in the knee?

Answer 13

Prevents transverse movement pf the two bones (lateral or medial rotation)-Translation
Stops Varus (hinging forwards)

Question 14

What is the function of the MCL ligament in the knee?

Answer 14

Stops opposite of the LCL
Stops valgus (hinging backwards)

Question 15

What is the function of the ACL ligament in the knee?

Answer 15

Stops the tibia translating anteriorly to the femur

Question 16

What is the function of the PCL ligament in the knee?

Answer 16

Stops the tibia translating posteriorly to the femur

Question 17

What happens if ligaments tear?

Answer 17

Instability of the joint/ increases range of movement/ buckles/ possible dislocation if multiple tears/ swelling

Question 18

What happens if ligaments thicken?

Answer 18

Stiffness/ lack of range of movement in certain directions depending on ligament

Question 19

What happens if there is too much synovial fluid/ synovium?

Answer 19

Too lubricated/ Swelling/ Possible translation of joint/ pain

Question 20

What happens if there is too little synovial fluid/ under active synovium?

Answer 20

Stiffness of joint/ more friction

Question 21

What happens if the joint capsule is weakened?

Answer 21

Increased range of movement at the joint/ decreased stability

Question 22

What happens if the joint capsule is thickened?

Answer 22

Decreased range of movement and stiffness/ increased stability/ lack of mobility in specific movement

Question 23

What happens if the articular cartilage is reduced?

Answer 23

Increased friction/ rubbing + eroding of the distal and proximal bones meeting at joint/ swelling/ pain/ decreased range of movement