Diagnostic Accuracy of Probe to Bone to Detect Osteomyelitis in the Diabetic Foot: A Systematic Review

The probe-to-bone (PTB) test is a commonly used clinical test for osteomyelitis (OM), but its utility has been questioned in clinical settings where the prevalence of OM is low. This article aims to systematically review the accuracy of the PTB test to diagnose diabetic foot OM. We searched Ovid Medline and Scopus databases for studies using the keywords "probe to bone," "osteomyelitis," and "diabetic foot" from 1946 to May 2015. We summarized characteristics of the included studies and pooled the accuracy numbers using a bivariate random-effects model. Seven studies met our inclusion criteria. Pooled sensitivity and specificity for the PTB test was 0.87 (95% confidence interval [CI], .75-.93) and 0.83 (95% CI, .65-.93), respectively. We conclude that the PTB test can accurately rule in diabetic foot OM in the high-risk patients and rule out OM in low-risk patients.