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Early MRI in acute knee haemarthrosis not supported by published evidence

Three Part Question

In [young adults with acute knee haemarthrosis with no obvious fracture] is [early MRI better than arthroscopy] in [diagnosing intra-articular pathology]?

Clinical Scenario

A young man comes into the emergency department after sustaining a knee injury while playing football. Examination reveals a tense haemarthrosis; there is no evidence of fracture on x-ray. You wonder whether a MRI scan would be better than an arthroscopy to establish a diagnosis.

Search Strategy

Medline 1966-12/98 using the OVID interface.
[{exp magnetic resonance imaging OR magnetic resonance image$.mp OR magnetic resonance OR OR exp nuclear magnetic resonance OR} AND (exp knee OR exp knee injuries OR exp knee joint OR knee$.mp} AND {exp hemarthrosis OR OR})] LIMIT to human and english language.

Search Outcome

26 papers found of which 24 were irrelevant to the study question or of insufficient quality for inclusion.

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Lundberg M et al
69 patients with unilateral knee haemarthrosis. MRI within days vs arthroscopy at a mean of 6 daysProspective single blind diagnosticACL tearssensitivity 86%, specificity 92%Small sample size
Medial meniscal tearssensitivity 74%, specificity 66%
Lateral meniscal tearssensitivity 50%, specificity 84%
Medial collateral ligament tearssensitivity 56%, specificity 93%
Adalbert T et al
40 patients with acute traumatic intra-articular haemorrhage. MRI within 1 week vs arthroscopy within 1 weekProspective diagnosticMeniscal tearssensitivity 76%, specificity 29%
sensitivity 97%, specificity 50%
Small sample size


Arthroscopy was used as a gold standard in both selected studies. MRI lacks both the sensitivity required for a SnOut and specificity required for a SpIn on this evidence. The evidence only applies to the conditions stated (haemarthrosis and investigation within 1 week) and different results might be found at different times.

Clinical Bottom Line

The evidence does not support early use of MRI scanning in acute knee haemarthrosis.


  1. Lundberg M, Odensten M, Thuomas KA et al. The diagnostic validity of magnetic resonance imaging in acute knee injuries with hemarthrosis. A single-blinded evaluation in 69 patients using high-field MRI before arthroscopy. Int J Sports Medicine 1996;17(3):218-222.
  2. Adalberth T, Roos H, Lauren M et al. Magnetic resonance imaging, scintigraphy, and arthroscopic evaluation of traumatic hemarthrosis of the knee. Am J Sports Med 1997;25(2):231-237.