diabetic foot ulcer

We sometimes see diabetic patients in the ED for a worsening foot ulcer. Sometimes it’s the chief complaint. Other times, however, you just notice it on physical exam. So, be sure you examine the feet of your diabetic patients. Occasionally, you’ll be surprised by what you find.

Several questions come up with diabetic foot ulcers:

  • Is it a true diabetic foot ulcer, or is it an arterial or venous insufficiency ulcer?
  • Is there underlying osteomyelitis?
  • How can I best diagnostically work this foot ulcer up for osteomyelitis?
  • What is the Wagner grade of this ulcer? (I think it’d be Grade 2.)

Thanks to JAMA‘s Clinical Rational Examination series, there is a systematic review of diabetic leg ulcers and osteomyelitis. Here are the highlights:

PV Card: Diabetic Leg Ulcer and Osteomyelitis

Adapted from [1] Go to ALiEM (PV) Cards for more resources.

Below is the Fagan nomogram to help you plot out your post-test probability based on your likelihood ratios. The example given is if your pretest probability is 25% and your LR is 10. Your post-test probability would be 80%.



  1. Butalia S. Does This Patient With Diabetes Have Osteomyelitis of the Lower Extremity? JAMA. 2008;299(7):806. doi: 10.1001/jama.299.7.806
Michelle Lin, MD
ALiEM Founder and CEO
Professor and Digital Innovation Lab Director
Department of Emergency Medicine
University of California, San Francisco
Michelle Lin, MD


Professor of Emerg Med at UCSF-Zuckerberg SF General. ALiEM Founder @aliemteam #PostitPearls at https://t.co/50EapJORCa Bio: https://t.co/7v7cgJqNEn
Michelle Lin, MD