Paucis Verbis: Does this DM leg ulcer have osteomyelitis?

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:

You can download this PV card:  [MS Word] [PDF]

See other Paucis Verbis cards.

Below is the Bayes 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%.

Reference

Butalia S et al. Does This Patient With Diabetes Have Osteomyelitis of the Lower Extremity? JAMA. 2008; 299(7), 806-13. DOI: 10.1001/jama.299.7.806.
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