Flashcards in Cartilage injuries and arthritis Deck (31):
Where is hyaline cartilage found?
Covering the surface of bones at synovial joints
What are the functions of hyaline cartilage?
Describe the structure of hyaline cartilage
Collage type II
What do chondocytes do?
Produce collagen (type II), proteoglycans and enzymes which help maintain the extracellular matrix
How does hyaline cartilage receive it's nutrition?
What is the function of proteoglycans?
Highly hydrophilic molecules which "inflate like balloons" to provide compressive strength
What is the function of collagen?
What are proteoglycans made of?
Hyaline cartilage defects can be traumatic or atraumatic. Give some examples of both
- Ligament injury
- Osteochondritis dissecans
- Inflammatory arthritis
Which type of cartilage injuries heal? What is different about healed cartilage as compared to normal cartilage?
Not hyaline but fibrocartilage which is less wear resistant with greater friction
What is osteochondritis dissecans?
Area of the knee loses its blood supply and cartilage +/- bone fragment detachment
In what age group is osteochondritis dissecans most common?
How is osteochondritis dissecans managed?
May heal/resolve spontaneously
Can pin in place if detaching on MRI
Can fix or remove if detached
Cartilage regeneration in severe cases
Is cartilage regeneration more effective on big or small defects?
Which joint can cartilage regeneration techniques NOT be performed on? Why?
There is too much sheer stress at this joint for it to be effective
What are the techniques used for cartilage regeneration?
What does MACI stand for?
Membrane induced autologous chondrocyte implantation
What are the contra-indications to cartilage regeneration?
Radiographic signs of osteoarthritis
Why are open procedures not great with respect to cartilage regeneration?
Air is toxic to hyaline cartilage
What techniques of cartilage regeneration are used in tayside and why?
Microfracture - cheap and easy
Allograft - larger defects +/- bone damage
What is osteoarthritis?
Pathology of the joints resulting from imbalance of cartilage breakdown and regeneration
What predisposes to osteoarthritis?
Degenerate meniscal tear
How is osteoarthritis initially managed?
Activity modification, aids, etc
When are steroid injections indicated in osteoarthritis?
Acute flare ups
What are the risks of steroid injection with respect to osteoarthritis?
Too many injections can accelerate OA
When is osteotomy indicated in osteoarthritis?
Early medial compartment OA in a varus leg
When is debridement and washout indicated in osteoarthritis?
Never because it doesn't work
Which compartment of the knee will be under the most stress in a varus and valgus knee respectively?
Varus - medial
Valgus - lateral
How can the directions of the legs in genu varum and valgus be remembered?
VaRum - feet Return
VaLgus - feet Leave
When is knee replacement indicated for osteoarthritis? Which type of knee replacement is most effective?
Elderly patients with end stage disease.
Total replacement has better results than partial replacement