MRI Criteria
NHS Tayside RefGuide
Warning
Agreed byBarry Oliver Consultant Radiologist, Graeme Foubister, Petros Boscainos and Richard Buckley Consultant Orthopaedic Surgeons
Who to refer
Primary care requested MRI indicated if:
- A knee XR must have been obtained within 6 months of MRI request
- Suspected acute meniscal tear
- previous injury with medial joint line tenderness and pain worsened by external rotation at 90 degrees knee flexion or
- previous injury with lateral joint line tenderness and pain worsened by internal rotation at 90 degrees knee flexion
- Instability
- previous injury and subsequently, knee gives way during rotation or pivoting.
Who not to refer
Primary Care MRI NOT indicated if:
- Patients under 15 or over 60
- Locked knee
- symptoms are continuous, not momentary or intermittent.
- a locked knee lacks at least 15 degrees of extension and cannot flex to 90 degrees (such patients need urgent orthopaedic referral with a view to arthroscopy – MRI is unnecessary and delays treatment)
- Pseudolocking
- (not to be confused with locking, this is momentary stiffness following a period of immobility – typically in obese people with patellofemoral OA)
- Knee dislocation or other severe acute injury (such patients are orthopaedic emergencies and should be dealt with by secondary care)
- Any osteoarthritis (OA) on an x-ray
- Obese patients with any clinical or radiographic evidence of OA (OA is very common in obese people – MRI in knees with OA often shows meniscal damage that is not treatable by arthroscopy)
- Any previous meniscal surgery (post-operative menisci simulate meniscal tears on MRI – direct orthopaedic clinic referral is appropriate in such patients)
- Active knee inflammatory arthritis, unless symptoms relate to a recent injury
- Patello-femoral joint dysfunction (anterior knee pain).
How to refer
MRI can be requested on ICE via Vision subject to the above criteria.