Baker's Cyst

Question 1

What is it

Answer 1

Fluid filled sac in the popliteal fossa

Question 2

What are the causes

Answer 2

Degenerative changes
Meniscal tears
OA
Inflammatory arthritis

Question 3

How does it present

Answer 3

Pain
Fullness
Pressure
Palpable lump
Restricted range of motion
Oedema if cyst compresses venous drainage

Question 4

What are examination findings

Answer 4

Lump most apparent when standing with knees fully extending
Foucher’s sign - lump gets smaller or disappear wen knees flexed 45 degrees

Question 5

What are differentials

Answer 5

DVT
Abscess
Popliteal artery aneurysm
Ganglion cyst
Lipoma
Varicose veins
Tumour

Question 6

How does a ruptured Baker’s cyst present

Answer 6

Pain
Swelling
Erythema

Question 7

What are investigations

Answer 7

USS
MRI to further evaluate

Question 8

What is treatment if asymptomatic

Answer 8

No treatment required

Question 9

What is non-surgical management

Answer 9

Modified activity
Pain relief
Physio
USS guided aspiration
Steroid injections

Question 10

What does surgical management involve

Answer 10

Treating underlying knee pathology potentially contributing to the cyst