Musc - Knee

Question 1

Differentials for knee pain and stiffness

Answer 1

• Knee OA
• Patellofemoral OA
• Patellar fracture
• Ligament injury
• Meniscal injury
• Crystal arthropathy

Question 2

Risk factors for knee OA

Answer 2

Constitutional

• Age
• Female gender
• Obesity

Local

• Prev. joint injury
• Occupational/recreational joint stresses
• Joint laxity/malalignement

Question 3

Mx of knee OA

Answer 3

Conservative

• Weight loss
• Stop smoking
• Physio/exercise programmes

Medical
- analgesia (paracetamol, topical NSAIDs)

Surgery

• Total knee replacement
• Partial knee replacement (done in 10% - when disease is localised to either medial or lateral compartment)

Question 4

Presentation of patellofemoral OA

Answer 4

Anterior knee pain (worse when doing things that pressurise the patella e.g. climbing stairs)

joint stiffness/swelling

Question 5

Differentials for ACL injury

Answer 5

Collateral ligament tear
Meniscal tear
Tibial plateau fracture

Question 6

Differentials for ACL injury

Answer 6

Collateral ligament tear
Meniscal tear
Tibial plateau fracture

Question 7

Ix for ACL tear

Answer 7

MRI knee

Question 8

Mx of ACL tear

Answer 8

Conservative
Quadricep strength training to stabilise joint

Surgical
ACL repair - performed using an artificial graft after months of physio

Question 9

Most common knee ligament injury and mechanism

Answer 9

MCL - blow to the lateral aspect of the knee

Question 10

Presentation of MCL injury

Answer 10

‘Pop’ sound + immediate medial knee pain

Swelling after a few hours

Question 11

Grading of MCL injury

Answer 11

Grade I – mild injury, with minimally torn fibres and no loss of MCL integrity
Grade II – moderate injury, with an incomplete tear and increased laxity of the MCL
Grade III – severe injury, with a complete tear and gross laxity of the MCL

Question 12

Mx of MCL injury

Answer 12

Conservative
- Analgesia and physio

For Grade 2 or 3
- Knee brace + weight bearing/strength training as tolerated

Question 13

Types of meniscus tear and most common

Answer 13

Vertical
Longitudinal (Bucket handle - most common)
Transverse
Degeneration

Question 14

Presentation of meniscus tear

Answer 14

Tearing sensation
Sudden onset knee pain
‘Locking’ (if free body within the knee, most commonly in bucket handle tears)
Joint effusion

Question 15

Mx of meniscus tears

Answer 15

For small tears: RICE

For larger tears: Arthroscopic meniscus removal or repair

Question 16

What is Iliotibial band syndrome

Answer 16

Inflammation of the iliotibial band aponeurosis of gluteus maximus and tensor fasciae latae. The most common cause of lateral knee pain in young athletes. Thought to be caused by repeated flexion and extension of the knee

Question 17

Mx of Iliotibial band syndrome

Answer 17

Analgesia
Physiotherapy
Potentially corticosteroid injections

Surgery - release of iliotibial band - indicated if symptomatic after 6 months of maximal Tx

Question 18

Presentation of patellar fracture

Answer 18

Anterior knee pain
Hx of direct patellar trauma
Unable to straight leg raise
Swelling and bruising

Question 19

Mx of open fractures

Answer 19

- Resuscitate in ED
		○ Fluids
		○ Analgesia
		○ Blood
		○ Tetanus booster and vaccination
		○ Remove any obvious debris
		○ Photograph wound 

- Transfer to theatre
	○ Debridement of wound and fracture site
	○ Reduction

Question 20

What is a Baker’s cyst

Answer 20

A Popliteal expansion of synovial fluid

Question 21

Differentials for popliteal cystic mass

Answer 21

Popliteal artery aneurysm
Soft tissue tumour
Baker’s cyst
Haematoma

Question 22

RFs for Baker’s cyst

Answer 22

Osteoarthritis
Idiopathic
Past knee injuries/trauma
Inflammatory diseases e.g. RA

Question 23

Ottawa knee rules (5 things)

Answer 23

Age >55 
Isolated patellar tenderness
Unable to flex knee to 90 degrees
Fibular head tenderness
Unable to weight bear >4 steps immediately and in ED

If any present, requires imaging

Question 24

Ottawa ankle rules

Answer 24

Tenderness at:

• Malleolar (posterior tip or lateral or medial malleolus)
• Midfoot (Navicular, base of 5th metatarsal)

Unable to weight bear 4 steps