4: Cartilage injuries of the knee Flashcards
Which type of cartilage covers synovial joints?
Hyaline cartilage
What is the purpose of hyaline cartilage in synovial joints?
Distributes load
Decreases joint friction
What are the three components of hyaline cartilage, apart from chondrocytes?
Water
Collagen
Proteoglycans
How do chondrocytes gain nutrition?
Synovial fluid
Bone marrow
What are the two broad categories of cartilage injury?
Traumatic
Atraumatic (OA, inflammatory arthritis)
What material replaces hyaline cartilage when it is damaged?
Fibrocartilage
more friction, less wear resistant, overall a bit crap
What is osteochondritis dissecans?
Cracks in cartilage and subchondral bone
May splinter off into joint cavity, produce locking of the knee joint
Why does cartilage and bone crack in osteochondritis dissecans?
Loss of blood supply
What can be carried out to treat osteochondritis dissecans?
Cartilage regeneration techniques
Describe a common cartilage regeneration technique.
Drilling holes in cartilage
bleeding, blood clots form, stem cells differentiate into chondrocytes and lay down fibrocartilage, “repairing” defect
How long does the fibrocartilage produced by a cartilage regeneration technique stick around?
About 5 years
Not long, but can be helpful for patient
What “wear and tear” disease of joints involves an imbalance between cartilage breakdown and repair and leads to joint deformity?
Osteoarthritis
How is early osteoarthritis treated?
Non-pharmacological: weight loss, walking stick, exercise, activity modification
Pharma: basic analgesia
When would steroid injections be used for OA?
Rarely in the case of an acute flare-up of disease
What surgery can be carried out to reduce the OA impact of pathological genu varum / valgum?
Osteotomy
literally breaking the bone and adjusting the joint alignment
