Suspected meniscal / ligament injury

Clinical evaluation

History of recent trauma with any of:

• Pop, tearing sound at time of injury

• True locked knee (unable to flex/extend at all)

• Clinical instability (when testing ligaments)

• Disproportionate bruising, swelling or pain

Examination

• often in acute knee injuries, patients may be too painful to examine fully. (clinical suspicion largely based from history of mechanism of injury and features) - once this acute phase has settle, the examination becomes more meaningful.

• collateral ligament injuries - may have findings of joint space opening on varus or valgus stress, with localised pain and bruising on the side of the knee

• cruicate ligament injuries - causes tibia to translate abnormally anteriorly (if ACL ruptured), or posteriorly (if PCL ruptured). These may be detected by the Lachman's test / Drawers test. Rotational instability could be detected by pivot shift test. (often these are too painful to perform acutely)

• meniscal injury - these may present with true locking of the knee (often held in flexion) due to trapped torn meniscus. patient may have tenderness on palpation of the joint line. Provocation test such as McMurry's test are often too painful to perform acutely.

XR

• look for tell-tail signs for ligament / meniscal injury, e.g.:

  • Segond fracture - ACL injury

  • Fibular head avlusion fracture "arcuate sign" - ACL, PCL, posterolateral corner injury

• look carefully to rule out other acute knee fractures! (e.g. tibial plateau, patella)

• large haemarthrosis without obvious fracture may indicate an occult undisplaced fracture. If unsure - get these reported / refer to ortho oncall for advice.

A&E management

1. offer analgesia

2. ensure patient have space in waiting area to elevate limb. (ideally above heart level, with ice-pack over the knee if available (Rest, Ice, Compression, Elevation)

3. clinical evaluation as above

4. offer cricket pad splint for comfort (beware prolong use can lead to knee stiffness, Do not use for more than 7 days, and ensure regular removal for ROM exercises)

5. offer crutches for walking

6. refer to MSK review clinic

ESP (Extended Scope Physiotherapy) Service in ED run MSK review clinics for this type of injury Mon-Fri. The ESPs aim to review the patients within 1 week of injury and if appropriate are able to request an MRI and refer directly to the acute knee clinic.