Cartilage Joint Injections

Question 1

What are the layers of a healthy joint?

Answer 1

• Synovial membrane
• Joint capsule
• Cartilage
• Subchondral bone

Question 2

What are the 2 layers of the synovial membrane?

Answer 2

1. Subintimal –> contains blood supply and innervation
2. Intimal –> contains synoviocytes –> Macrophage type A ( for phagocytosis) and Fibroblast type B (hyaluronic acid, aggrecan, collagen, cytokines, eicosanoids, proteases

Question 3

What is the function of subchondral bone?

Answer 3

Shock absorption

More deformable than corticle bone, bone damage can lead to osteoarthritis

Question 4

What is the purpose of the articular cartilage?

Answer 4

Defines joint health

Creates joints surface and made of EC matrix formed of water, proteoglycans, and hyaluronic acid

Question 5

What is the function of hyaluronic acid with glycosaminoglycan formation?

Answer 5

• Forms the backbone of structural molecules found in joints

Question 6

What do you see in a joint with OA?

Answer 6

• Effusion, decreased synovial fluid viscosity, increased TP with normal cell count
• Cartilage color turns from blue to yellow

Question 7

What are the clinical signs of OA?

Answer 7

Lameness, joint pain, decreased range of motion, joint effusion

can be present with or without radiographs

Question 8

What is the goals of treating OA?

Answer 8

• Reverse the reversible and reduce the irreversible
• Eliminate pain and inflammation
• Restore synovial fluid to normal

Question 9

How can you manage OA?

Answer 9

• Chondroprotectives
• Corticosteroids
• NSAIDs
• Blood based products/ cell based treatments

Question 10

What are some examples of chondroprotective agents?

Answer 10

• Hyaluronic acid
• Polysulfated glycosaminoglycan
• Polglycan
• Pentosan Gold + Halo

Question 11

What causes osteoarthritis?

Answer 11

Single injuries or use trauma

Question 12

What is the function of bone sclerosis?

Answer 12

Strengthens bone

Question 13

What is an osteophyte? Enthesiophyte?

Answer 13

Osteophyte - bony projections that form along joint margins

Enthesiophyte - bony projections that form at tendon or ligament attachments

Question 14

What is Sodium Hyaluronate/ hyaluronic acid?

Answer 14

• A long unbranched non-sulfated GAG produced by chondrocytes
• Provides viscoelasticity, boundary lubrication, free radical scavenging, increases endogenous HA production and reduces aggrecan degradation
• Also is chondroprotective IA, analgesic, and reduces cartilage fibrillation

Question 15

What dose should you give HA at and why?

Answer 15

Give 20 mg per joint 1/ week for 3 weeks

• May improve synovial fluid viscosity, joint lubrication, and anti-inflammatory
• Taken from human med

Question 16

Is the molecular weight of HA related to its function?

Answer 16

Not really sure –> a controversial subject

Question 17

What is the effectiveness of giving HA IV vs. IA?

Answer 17

IV - Treats multiple joints less effectively
** study on racehorses showed IV allowed them to continue longer without IA injections, and had decreased lameness and inflammatory mediators

IA- Most efficacious

Question 18

What other drug can you mix with HA to increase anti-inflammatory properties?

Answer 18

Triamcinolone (TA)

Question 19

How do Polysulfated Glycosaminoglycans work?

Answer 19

• Specific mechanism unknown
• But inhibits degradative enzymes, counteracts IL-1, reduces synovial effusion
• Brand name is Adequan

Question 20

What are the positives and negatives of adequan?

Answer 20

Positive - Increases GAGs and decrease inflammatory molecules (PGE2) –> IA only

Negative - May allow bacterial infection –> use Amikacin to prevent

Question 21

What is polyglycan?

Answer 21

Post-surgical joint lavage formula containing:

1. HA
2. Chondroitin sulfate
3. N-acetyle-D-glucosamine

**Has been shown to improve symptoms of OA

IV injections can potentially worsen the disease though

Question 22

What are the benefits of PSGAGs compared to HA?

Answer 22

PSGAGs - greater magnitude of positive effects on the synovial
membrane

HA - greater effect on
articular cartilage fibrillation

Question 23

What are some corticosteroids that can be used for joint disease?

Answer 23

Triamcinolone acetonide - chondroprotective effects

Methly prednisolone acetate - bad for articular cartilage at therapeutic doses

Betamethasone - no bad effects on articular cartilage

Question 24

What are some blood-based products?

Answer 24

Autologous conditioned serum

Platelet rich plasma

Question 25

What are some cell based treatments?

Answer 25

 Mesenchymal stem cells
 Adipose derived
 Bone marrow derived
 Umbilical stem cells
 Allograft stem cells