Screening for Osteomyelitis Using Thermography in Patients with Diabetic Foot

One of the most serious complications of diabetic foot (DF) is osteomyelitis, and early detection is important. To assess the validity of thermography to screen for osteomyelitis, we investigated thermographic findings in patients with both DF and osteomyelitis. The subjects were 18 diabetic patients with 20 occurrences of DF who visited a dermatology department at a hospital in Tokyo and underwent evaluation by magnetic resonance imaging (MRI) and thermography between June 2010 and July 2012. Osteomyelitis was identified by MRI. Thermographs were taken of the wounds and legs after bed rest of more than 15minutes. Two wound management researchers evaluated the range of increased skin temperature. There were three types of distribution of increased skin temperature: the periwound, ankle, and knee patterns. Fisher’s exact test revealed that the ankle pattern was significantly more common in the group with osteomyelitis than in the group without osteomyelitis (P = 0.011). The positive predictive value was 100%, and the negative predictive value was 71.4%. Our results suggest that an area of increased skin temperature extending to the ankle can be a sign of osteomyelitis. Thermography might therefore be useful for screening for osteomyelitis in patients with DF.