Week 3: Diagnosis

Question 1

Common causes of anterior knee pain?
Less common causes of anterior knee pain?
Not to be missed?

Answer 1

Common
- Patellofemoral pain
- Patellar tendinopathy

Less Common
- Osgood Schlatter Lesion (adolescent)
- Sinding Larsen Johansson lesion (adolescent)
- Stress fracture of the patella
- Fat pad impingement/Hoffa’s pad syndrome
- Pre-patellar/infrapatellar bursitis

Not to be missed
- Osteochondritis dessicans
- Slipped capital femoral epiphysis
- Perthes’ disease

DON’T FORGET: Chondromalacia Patellae and OA

Question 2

Common causes of lateral knee pain?
Less common causes of lateral knee pain?
Not to be missed?

Answer 2

Common
- Illiotibial band friction syndrome
- Lateral meniscus abnormality (minor tear, degenerative change or cyst)

Less Common
- Patellofemoral syndrome
- Osteoarthritis of the lateral compartment
- Excessive lateral pressure syndrome
- Synovitis of the knee joint

Not to be missed
- Common peroneal nerve injury
- Slipped capital femoral epiphysis
- Perthes’ disease

Question 3

Common causes of acute knee pain?
Less common causes of acute knee pain?
Not to be missed?

Answer 3

Common
- Medial/lateral meniscus tear
- MCL sprain
- ACL sprain
- PCL sprain
- Patellar dislocation
- Articular cartilage injury

Less common
- Patellar tendon rupture
- Quadricep tendon rupture
- LCL sprain
- Acute fat pad impingmenet
- Avulsion of bicep femoris tendon
- Superior tibiofibular joint injury

Not to be missed:
- Fracture of the tibial plateau
- Avulsion fracture of tibial spine
- Osteochondritis dissecans (adolescent)
- Complex regional pain syndrome type 1
- Quadriceps muscle rupture

Question 4

Diagnosing OA (key features)

Answer 4

Age >50
Stiffness < 30 min
Crepitus
Bony tenderness & enlargement
ESR <40mm/hour
Rheumatoid factor <1:40
Sinovial fluid signs of OA (clear, viscous or WBC count)

Question 5

Patellofemoral pain
- What is it?
- Location (feeling)
- Aggravating activities?
- Physical exam findings?
- X-ray?
- MRI?

Answer 5

What is it? Presence of retropatella pain (around the knee cap) or peripatella (behind the kneecap) pain

Location? Anterior knee, around the kneecap (dull, ache, burning)

Aggravating activities? Stairs, squatting, sitting

Physical exam findings? Tenderness around kneecap, patellar maltracking

Normal or subtle signs suggestive of CMP

Often inconclusive

Question 6

Chondromalacia Patellae
- Pain location
- Aggravating activities
- Physical exam findings
- X-ray
- MRI

Answer 6

Location: Usually more localised directly under the kneecap where the cartilage is located (sharp or aching pain, sometimes with catching sensation.

Aggravating activities: Similar to PFPS (sometimes direct pressure)

Physical exam findings: tenderness under kneecap, joint effusion (possible)

X-ray: sometimes fragmented appearance of the cartilage beneath the kneecap

• MRI: may show cartilage damage

Question 7

Patella tendinopathy