Diagnostic performance of ultrasonography for diabetic foot osteomyelitis.

OBJECTIVE: This study aims to analyze the potential diagnostic capability of ultrasonography in detecting diabetic foot osteomyelitis (DFO) in patients with diabetic foot ulcers (DFUs).

APPROACH: A 1-year prospective study was conducted on 47 consecutive patients with active DFUs and suspicion of DFO at a specialized diabetic foot unit. The following ultrasonographic (US) features were evaluated at baseline: 1) periosteal reaction; 2) periosteal elevation; 3) cortical disruption; 4) sequestrum; and 5) positive power Doppler. Primary outcome measure aimed to establish the effectiveness of ultrasonographic features compared to aseptic bone culture for diagnosing DFO. Receiver operating characteristic (ROC) curves were utilized to evaluate the diagnostic performance of the ultrasonographic features. Sample size could not be performed as it becomes the first study to assess US features for the diagnosis of DFO. The research adhered to the guidelines for diagnostic accuracy studies (STARD 2015).

RESULTS: All patients (n=24) diagnosed with DFO exhibited positive power Doppler, resulting in a sensitivity (S) and specificity (SP) of 1 and an area under the curve (AUC) of 1 (P <0.001 [1-1]). Cortical disruption was present in 23 patients (95.8%) with DFO, yielding an S of 0.93, SP of 1, and an AUC of 0.96 (P <0.001 [0.88-1]).

INNOVATION: It validates the diagnostic value of US for DFO, as it is the first and largest study of its kind to establish a clear reference standard to guide clinician decision-making.

CONCLUSION: This study demonstrates the effectiveness of cortical disruption and positive power Doppler in assessing DFO through ultrasonography.