Module 2- Joints and Total Joint Replacement

Question 1

How many types of joints are there?

Answer 1

3

Question 2

What are the 3 types of joints?

Answer 2

• Fixed
• Cartilaginous
• Synovial

Question 3

Fixed joints

Answer 3

Immovable or fixed joints hold our skull together

Question 4

Cartilaginous joints

Answer 4

Slightly movable joints (cartilaginous) are the joints in the vertebral column

Question 5

Synovial joints

Answer 5

Freely movable joints (synovial) comprise 90% of our joints

Question 6

What makes up a synovial joint?

Answer 6

Question 7

What can go wrong with joints?

Answer 7

Tendons/ligament injury
- Making movement of the joint painful and difficult

Antagonistic muscle damage due to too overloading
- Making movement of the joint painful and difficult

Dislocation
- The bones move out of position, causing pain and preventing joint movement

Cartilage damage
- Movement becomes painful or impossible and the joint becomes inflamed

Question 8

Diagram showing what can go wrong with joints

Answer 8

Question 9

Another example of something going wrong with joints- osteoarthritis

Answer 9

• Osteoarthritis is a degenerative joint disease and is the most common chronic condition of the joints.
• It is characterized by degeneration of articular cartilage leading to increased friction between bones.
• Traumatic cartilage damage presents similarly to osteoarthritis

Question 10

Arthritis- the damage in degeneration

Answer 10

• In arthritis, articular cartilage degenerates faster than its regeneration and as a result the cartilage cannot cope and often fragments.
• As a result, there is loss of joint movement and pain.
  Factors leading to arthritis include aging, sport, injury, obesity and genes.

Question 11

Graph sowing increase in prevalence of arthritis with age

Answer 11

With the aging US population, the prevalence of doctor-diagnosed arthritis is expected to increase in the coming decades

Question 12

Cost of arthritis

Answer 12

Total costs associated with arthritis are over 82 billion USD per year, including hospital + drug costs, nursing home costs, and lost productivity and work

Question 13

How can we treat arthritis?

Answer 13

• Pain is initially treated with over the counter pain medication and anti-inflammatories.
• As arthritis progresses, more invasive techniques are used to manage pain. But these treatments aren’t curative and only prolong surgery.

Question 14

Treatment 1 for arthritis- Corticosteroid Injections

Answer 14

• Corticosteroid injections, which resemble cortisol (stress hormone), are used to treat inflammation.
• They are advantageous because they help with pain relief, but can be dangerous since they can loosen soft tissues (cartilage + tendons), leading to further damage.

Question 15

Treatment option 2 for arthritis- Hyaluronic Acid Injections

Answer 15

• Hyaluronic acid injections are one of the major components of synovial fluid (the other is lubricin), responsible for viscous and elastic components.
• There are no serious side effects to this treatment option, however effectiveness has not been well established.

Question 16

Treatment option 3 for arthritis- coolief

Answer 16

• Coolief is an advanced procedure that uses cooled radiofrequency energy to safely target the sensory nerves causing pain.
• This is called an ablation (meaning to destroy) procedure — and was FDA approved in 2017.

Question 17

Partial and complete joint replacement

Answer 17

Depending on the damage, a joint can be partially or completely replaced

Question 18

Characteristics of prosthetic joints

Answer 18

Characteristics of prosthetic joints include:
●Strength
○ Mechanical stress
○ Fatigue strength
●Flexibility
●Biocompatibility
●Resistance to wear
●Resistance to corrosion

Question 19

Wear rate and coefficient of friction of joint prosthesis materials

Answer 19

Typical metals include titanium. Typically non-ferromagnetic. Safe for MRI

Question 20

Cemented versus Cementless Fixation in joint prosthetics

Answer 20

Cemented:
* Elderly (>65) * Low demand
* Better early fixation
* late loosening

Cementless:
* Younger
* More active
* Protected weight-bearing first 6 weeks
* Better long-term fixation

Question 21

What are the two largest weight bearing joints in the body?

Answer 21

• Hip (ball joint)
• Knee (hinge joint)

Question 22

Anatomy of the knee

Answer 22

There are three bones (femur, tibia, and patella), ligaments, and articular cartilage

Question 23

Diagram of knee prosthetics

Answer 23

Femoral and tibial implant metal alloy, patellar implant and joint liner polyethylene

Question 24

Bone cuts and implantation for knee prosthetic

Answer 24

Question 25

Anatomy of the hip

Answer 25

There are two bones (the femur and pelvis), ligaments, and articular cartilage

Question 26

The Mechanisms of Hip Prosthetics

Answer 26

There are four components, the Femoral stem and neck, the Femoral head, the Polyethylene liner, and the Acetabular shell

Question 27

How is a hip replacement implanted?

Answer 27

Question 28

Hip resurfacing

Answer 28

An option for younger patients — Hip Resurfacing

Question 29

Post-op complications from hip surgery

Answer 29

Complications may include: ● Infection ● Pain management ● Blood clot ● Lack of mobility ● Intense physical therapy ● Stiffening ● Loosening ● Dislocation (hip) ● Change in leg length (hip

Question 30

Total joint replacement- early failure

Answer 30

- Early TJR Failure (<10%)

Question 31

Total joint replacement- late failure

Answer 31

Late TJR Failure (symptoms > 5 years post-op)

Question 32

How long does a total joint replacement typically last?

Answer 32

Typically 20 years