Knee Injuries

Question 1

What are meniscal tears?

Answer 1

Damage of the menisci (C-shaped fibrocartilage found in knee joint).

Question 2

Where are the menisci and what are their function?

Answer 2

Rest on the tibial plateau
Shock absorbers of the knee
Increase articulating surface area

Question 3

What is the common mechanism of injury in meniscal tear?

Answer 3

Young patient who has twisted their knee whilst it is flexed and weight bearing

Question 4

What are the types of meniscal tear and which is most common?

Answer 4

Vertical
Longitudinal (bucket-handle)
Transverse
Degenerative

Question 5

What are the clinical features of meniscal tear?

Answer 5

Tearing sensation in the knee
Intense sudden-onset pain
Swelling of knee over 6-12 hours
May be locked in flexion

On examination: joint line tenderness, significant joint effusion, limited knee flexion

Question 6

What assessments should be made?

Answer 6

Plain radiograph to exclude fracture

MRI scan to confirm meniscal tear

Question 7

What is the management for acutely swollen knee?

Answer 7

RICE
For larger tears: arthroscopic surgery is indicated if:
- the tear is in the outer third of the meniscus (where it has a rich vascular supply), then the tear can be sutured back together
- the tear is in the inner third, then the tear is often trimmed (and middle third tears may either be repaired or trimmed)

Question 8

What are the risks of knee arthroscopy?

Answer 8

DVT

Damage to local structures such as saphenous nerve and vein, perineal nerve, popliteal vessels

Question 9

When does tibial plateau fracture occur?

Answer 9

OIn elderly/or trauma in young
Knee forced into valves or virus but the knee fractures before the ligament ruptures
Varus injury affects medial plateau, valves injury causes depressed fracture of lateral plateau

Question 10

How are tibial plateau fractures classified?

Answer 10

Schatzker classification
1 - vertical split of lateral condyle
2- vertical split of lateral condyle combined with an adjacent load bearing part of the condyle
3- depression of the articular surface with intact condylar rim
4 - fragment of medial tibial condyle
5 - fracture of both condyles
6 - combined condylar and subcondylar fractures