Lower Limb - Knee

Question 1

What type of bone is the patella, and where does it develop?

Answer 1

Sesamoid bone that develops within the quadriceps tendon

Question 2

What is the function of the patella besides improving quadriceps efficiency?

Answer 2

protects the knee from physical trauma

Question 3

How is the patella shaped in coronal and axial planes?

Answer 3

Roughly triangular

Question 4

What type of fracture is commonly seen in direct patella injuries?

Answer 4

An undisplaced crack or comminuted fracture

usually with an intact extensor mechanism

Question 5

What causes an indirect patella injury?

Answer 5

Forceful quadriceps contraction against a blocked extension

eg, tripping and catching the foot

Question 6

What fracture pattern is typical in indirect patella injury?

Answer 6

Transverse fracture with possible disruption of the extensor mechanism

Question 7

What clinical sign indicates an intact extensor mechanism?

Answer 7

Ability to perform a straight leg raise

Question 8

How can pain affect testing the extensor mechanism and how can it be improved?

Answer 8

Pain may limit movement; testing with the patient on their side reduces gravity and may help

Question 9

What imaging is used to diagnose a patella fracture?

Answer 9

At least two plain X-ray views

Question 10

How are undisplaced vertical patella fractures with an intact extensor mechanism managed?

Answer 10

Non-operatively with a hinged knee brace for 6 weeks and full weight bearing allowed

Question 11

What are the indications for operative management of patella fractures?

Answer 11

Displaced fractures or loss of extensor mechanism

Question 12

What long-term complication may result from disruption of the patellofemoral joint?

Answer 12

Secondary osteoarthritis

Question 13

What is the typical cause of a meniscal tear?

Answer 13

results from twisting injuries

Question 13

What is a common feature of pain in meniscal tears?

Answer 13

Pain is worse when straightening the knee

Question 14

What is a common functional issue associated with meniscal tears?

Answer 14

The knee may ‘give way.’

Question 15

What can displaced meniscal tears cause?

Answer 15

Knee locking

Question 16

Where is tenderness typically felt in a meniscal tear?

Answer 16

Along the joint line

Question 17

What is Thessaly’s test used for?

Answer 17

It is used to assess for a meniscal tear

Question 18

How is Thessaly’s test performed?

Answer 18

The patient stands on the sore leg with a bent knee and twists. If it causes pain, the test is positive

Question 19

A 22-year-old man presents to the minor injuries unit after twisting his left knee while playing rugby 5 hours ago. Although he was able to finish the game, he now reports that the knee locks intermittently and feels like it might give way. He is also experiencing intermittent knee pain and notes that the joint has started to swell within the last hour.

On examination, the left knee joint is swollen, left knee flexion and extension are reduced, and there ie tenderness along the anteromedial joint line. The right knee is unremarkable.

What is the diagnosis?

Answer 19

Meniscal tear

Question 20

A 32-year-old Sunday league rugby player presents to the emergency department with a painful knee. Upon history taking, she describes feeling a popping sensation in her right knee during the match, and upon clinical examination the knee is swollen, and the patient is unable to fully extend her knee.

Which one of the following tests is most likely to reveal the underlying diagnosis?

Answer 20

MRI - most appropriate imaging modality to diagnose meniscal tears

Question 21

A 22-year-old male presents to the emergency room with pain in the left knee following a twisting injury during a rugby match. He states that it has gradually swollen over the past 24 hours, and he is unable to fully extend it.

On examination, you note tenderness over the medial joint line, a joint effusion, and the joint is held in a flexed position. There is no laxity on the valgus stress test.

What is the most likely diagnosis?

Answer 21

Medial meniscus tear

Question 22

‘A 38-year-old man is playing football when he slips over during a tackle. His knee is painful immediately following the fall. Several hours later he notices that the knee has become swollen.
Following a course of non-steroidal anti-inflammatory drugs and rest the situation improves.

However, complains of recurrent pain. On assessment in the clinic, you notice that it is impossible to fully extend the knee, although the patient can do so when asked’

What does this describe?

Answer 22

Torn meniscus

Question 23

What is the typical mechanism of injury for a meniscal tear in younger patients?

Answer 23

Twisting force on a loaded knee, e.g. turning at football or squatting

Question 24

What symptom is suggestive of a displaced bucket-handle meniscal tear?

Answer 24

A locked knee with a 15° springy block to extension

Question 24

Which meniscus is more commonly torn?

Answer 24

Medial meniscus

Question 25

What investigation is most useful to confirm a meniscal tear?

Answer 25

MRI

Question 25

What does medial joint line tenderness suggest?

Answer 25

Medial meniscal tear

Question 26

What physical test may be positive in meniscal tears, though not always reliable?

Answer 26

McMurray’s test (or Steinman’s test)

Question 27

What is the first-line management for a young patient with an acute peripheral meniscal tear?

Answer 27

Arthroscopic meniscal repair

Question 28

What type of meniscal tear is more likely to be repairable if caught early?

Answer 28

Bucket handle tear

Question 28

LCL injury means what?

Answer 28

deficit in peroneal nerve

Question 29

What symptom helps differentiate a meniscal tear from other knee injuries?

Answer 29

Locking or catching sensation

Question 30

What is a Baker’s cyst also known as?

Answer 30

Popliteal cyst

Question 31

What distinguishes a primary from a secondary Baker’s cyst?

Answer 31

1. Primary: no underlying pathology = seen in children 2. Secondary = associated with joint disease like osteoarthritis (seen in adults)

Question 32

What is the typical management of Baker’s cysts in children?

Answer 32

Reassurance – they usually resolve spontaneously

Question 32

Where do Baker’s cysts present anatomically?

Answer 32

As swellings in the popliteal fossa behind the knee

Question 33

What is the most appropriate imaging modality to diagnose meniscal tears?

Answer 33

MRI

Question 34

You see an 81-year-old lady with a history of diabetes, osteoarthritis and hypertension. She twisted her leg whilst getting out of a car and developed increasing pain with weight bearing which has eased with simple analgesia. She also tells you she lumps her knee. On examination, she has a 4cm non-tender lump just below the popliteal fossa, which becomes tense on extending the leg. She has full power throughout. What is the most likely diagnosis?

Answer 34

Bakers cyst

Question 35

You suspect a meniscus tear if there's what present?

Answer 35

1. Knee pain with twisting or squatting 2. Clicking, locking, or catching 3. Joint line tenderness 4. A positive McMurray’s test

Question 36

A tall 18-year-old male athlete is admitted to the emergency room after being hit in the knee by a hockey stick. On examination his knee is tense and swollen. X-ray shows no fractures What does he have?

Answer 36

Dislocated patella

Question 37

A 60-year-old female is hit by a car travelling at speed whilst crossing the road. She sustains a fracture of the tibia. Which is the most likely fracture pattern associated with this case?

Answer 37

Comminuted fracture