Is MRI Overutilized In The Diagnosis Of Diabetic Foot Osteomyelitis?

Compelling work from our colleagues Gariani and coworkers from Geneva in Current Diabetes Reviews takes a look at the utility of magnetic resonance imaging (MRI) versus X-rays in the diagnosis and treatment of diabetic foot osteomyelitis.¹

In their study, they compared epidemiology and outcomes for diabetic foot osteomyelitis diagnosed with plain film X-ray versus those with positive MRI findings. The researchers considered intraoperative bone appearance and bone cultures to be the diagnostic gold standard. In the prospective study involving 390 cases of diabetic foot osteomyelitis in 186 patients, the study authors obtained 318 X-ray studies and 47 MRIs.¹ Only 18 cases of osteomyelitis had positive MRI findings with no plain radiographic indicators. 

After evaluating the duration of antibiotics, the number of surgical debridements and remission rates, the study authors found the cases with positive MRI findings only did not influence treatment nor remission of the osteomyelitis.

I think the balance of evidence may support that we have spend a great deal of time over-diagnosing and over-treating diabetic foot osteomyelitis. Most osteomyelitis is slow growing and yet we often take drastic and ablative action when we likely don’t need to do so. The data from this study seems to support that contention. 

Additionally, a pathway similar to the one described in this study, which discourages use of MRI, uses plain film X-ray and considers bone culture gold standard, could save health-care dollars while remaining effective in diagnosis.

I think we have to take a breath and reconsider what we do when caring for diabetic foot osteomyelitis. Perhaps we should approach it as one might address a slow-growing prostate cancer. Sometimes, there may be targeted surgical intervention. Sometimes, one may opt for pharmacological therapy. Sometimes, the most prudent course involves watchful waiting.

Dr. Armstrong is Professor of Surgery at the Keck School of Medicine at the University of Southern California. He is the Director of the Southwestern Academic Limb Salvage Alliance (SALSA). 

Editor’s Note: This blog originally appeared at: 

https://diabeticfootonline.com/2020/08/02/why-must-we-mri-x-ray-versus-magnetic-resonance-imaging-in-diabetic-foot-osteomyelitis-a-clinical-comparison/ . It is adapted with permission from the author.

Reference

1. Gariani K, Lebowitz D, Kressman B, Gariani J, Uckay I. X-ray versus magnetic resonance imaging in diabetic foot osteomyelitis: a clinical comparison. Curr Diabetes Rev. 2020. doi: 10.2174/1573399816999200729124134. Published July 29, 2020. Accessed August 7, 2020.