McMurray Test

For Medical Students

What It Tests

The McMurray test attempts to trap a torn meniscal fragment between the femoral condyle and the tibial plateau, and then to move it so the patient feels it.

It tests the meniscal body and the posterior horn, which is why the manoeuvre takes the knee through flexion.

It is a provocative test rather than a palpation finding, which is why it comes after joint line tenderness in the sequence. 4.9.2 covers that.

How It Is Performed

With the patient supine, flex the knee fully, holding the heel in one hand and the knee with the other so that a finger rests on each joint line.

For the medial meniscus, externally rotate the tibia and apply a valgus force, then extend the knee while maintaining both.

For the lateral meniscus, internally rotate the tibia and apply a varus force, then extend.

Feel for a click or a clunk at the joint line under the finger, and ask whether that reproduced their pain.

Repeat on the other knee for comparison, and expect the test to be uncomfortable, which is why it is performed late. 4.9.1 covers the sequence.

What a Positive Means

A palpable click or clunk at the joint line during the manoeuvre, with pain the patient recognises, is the classic positive.

Pain alone without a click is a weaker positive and is commonly recorded as positive, which is one reason the test's reported performance varies.

A click without pain is weaker still and is frequent in normal knees.

A positive on the medial manoeuvre points to the medial meniscus and a positive on the lateral manoeuvre to the lateral.

A negative test excludes very little, because the test is specific rather than sensitive.

MRCS Level

How It Is Performed

In a viva the expected description names the hand positions, the rotation, the stress and the extension, in that order, for each meniscus.

The candidate should also say what they are feeling for and where their fingers are, because the finger on the joint line is what makes the click a finding rather than a sensation.

Say that the test is uncomfortable and that you would warn the patient.

Say what you would accept as positive, because the definition varies between examiners and stating yours is better than assuming theirs.

What a Positive Means

The definition of a positive is the main source of variability in this test, and that is worth understanding rather than memorising.

A strict definition, requiring a palpable click with reproduction of pain, is more specific and less sensitive.

A loose definition, accepting pain alone, is more sensitive and much less specific, because pain on a forced rotation and extension is common in any irritable knee.

The original description is stricter than common practice, which is why reported performance differs so widely between studies.

That variability is a property of the test rather than of the examiners, and it is the reason the combination of findings matters more than the single test. 4.9.1 covers the combination.

How Good It Is

The McMurray test is specific rather than sensitive when performed and defined strictly.

It performs worse than joint line tenderness as a screen and better as a confirmation, which is the general pattern of the provocative tests.

It performs poorly in an acutely swollen knee, because a guarding patient will not permit the manoeuvre and a forced attempt produces pain regardless.

It performs poorly in a degenerate knee for the same reason pain-based positives are unreliable there.

No figures appear, under decision 023. The ranking against joint line tenderness and against the other provocative tests is the claim.

FRCS Level

How Good It Is

At decision level the McMurray test contributes to a combination and should not be weighted alone.

A strict positive with matching joint line tenderness and a matching history is a coherent picture and supports the tear being symptomatic.

A positive in a degenerate knee with diffuse tenderness adds little, because the manoeuvre provokes pain in that joint regardless.

A negative test in a patient with a convincing history does not change the plan, and treating it as reassuring is the commonest misuse.

The test contributes nothing to the question of repairability, which is a history and imaging question. 4.2.9 covers onset.

Where It Misleads

The commonest error is recording a positive on pain alone and then treating it as evidence.

The second is performing the test in an acute knee, where it is both uninformative and unkind.

The third is interpreting a click as a tear when painless clicks are common. 4.2.7 covers mechanical symptoms.

And forcing the manoeuvre in a knee with a suspected displaced fragment, which can convert a reducible block into a worse one and is a reason for care rather than enthusiasm. 4.9.8 covers mechanical locking.

Fellowship Level

Where It Misleads

After meniscal surgery the McMurray test is of limited value and the reasons are specific.

After a resection the fragment that would have been trapped is gone, so a negative test is expected and uninformative, while a positive may reflect the altered mechanics of a deficient meniscus. 4.9.10 covers deficiency.

After a repair the manoeuvre loads the repair, so performing it during the healing period is a decision rather than a routine.

In a knee with a transplant or scaffold the same caution applies and for longer.

The useful test after meniscal surgery is the search for a mechanical block rather than a provocative rotation, because that finding still means something. 4.9.8 covers it.

No figure here supports these claims, under decision 023.