Meniscal Tears of the Knee

Question 1

Explain the menisci.

Answer 1

C-shaped fibrocartilage around knee joint.

Menisci rest on the tibial plateau.

Work as shock-absorbers of the knee joint + increase articulating surface area.

Question 2

Difference between medial and lateral menisci.

Answer 2

Medial is less circular than lateral.

Medial is attached to MCL.

Lateral meniscus is not attached to LCL

Question 3

Most common causes of meniscal tears.

Answer 3

Trauma-related injury and degenerative disease.

Question 4

Mechanism of injury

Answer 4

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

Question 5

Types of meniscal tears

Answer 5

Vertical

Longitudinal (Bucket-Handle)

Transverse (Parrot-beak)

Degenerative

Question 6

What is the most common type of meniscal tear?

Answer 6

Longitudinal aka Bucket-Handle

Question 7

Clinical features

Answer 7

‘Tearing sensation’ in knee.

Intense sudden-onset pain.

Knee will swell slowly over a period of 6-12 hours.

In longitudinal tear the knee may be locked in flexion and patient won’t be able to extend their knee.

Question 8

Examination findings

Answer 8

Joint line tenderness

Significant joint effusion

Limited knee flexion

Question 9

Specific tests for meniscal tear.

Answer 9

McMurray’s test

Apley’s grind test

Both of them can be quite painful so many clinicans no longer use them.

Question 10

Dx

Answer 10

Fracture

Cruciate ligament tear

Collateral ligament tear

Osteochondritis dissecans

Question 11

Ix

Answer 11

Plain film radiographs to exclude a fracture

MRI scan is gold-standard and also useful to identify which type of tear it is.

Question 12

What does management depend on?

Answer 12

Severity of the tear.

Question 13

Immediate management of an acutely swollen knee.

Answer 13

RICE (Rest, ice, compression and elevation)

Most small (<1cm) meniscal tears will initially swell but pain will subside and become self-limiting.

Question 14

Indications of surgery

Answer 14

Larger tears or those remaining symptomatic.

Question 15

What surgery is done?

Answer 15

Arthroscopic surgery

Question 16

What technique is used depending on location of tear?

Answer 16

If the tear is in the outer third of the meniscus.
This part has a rich blood supply meaning the tear can often be sutured back together.

Inner third tear.
Tear is then often trimmed

MIddle third tears may either be repaired or trimmed.

Question 17

Complications

Answer 17

OA later in life

Knee-arthroscopy can cause DVT and damage to local structures like saphenous nerve and vein, peroneal nerve and popliteal vessels.