Clinical Inquiry: What's the best test for underlying osteomyelitis in patients with diabetic foot ulcers?

J Fam Pract. 2015 May;64(5):309-10, 321.


Magnetic resonance imaging (MRI) has a higher sensitivity and specificity (90% and 79%) than plain radiography (54% and 68%) for diagnosing diabetic foot osteomyelitis. MRI performs somewhat better than any of several common tests--probe to bone (PTB), erythrocyte sedimentation rate (ESR) >70 mm/hr, C-reactive protein (CRP) >14 mg/L, procalcitonin >0.3 ng/mL, and ulcer size >2 cm²--although PTB has the highest specificity of any test and is commonly used together with MRI. No studies have directly compared MRI with a combination of these tests, which may assist in diagnosis.

Publication types

  • Review

MeSH terms

  • Blood Sedimentation
  • C-Reactive Protein / analysis
  • Diabetic Foot* / complications
  • Diabetic Foot* / diagnosis
  • Foot / diagnostic imaging
  • Humans
  • Magnetic Resonance Imaging*
  • Osteomyelitis* / blood
  • Osteomyelitis* / diagnosis
  • Osteomyelitis* / etiology
  • Radiography
  • Sensitivity and Specificity


  • C-Reactive Protein