Diagnostic 'Divining Rod' for diagnosing limb-threatening bone infection — reliable or relic?

An often-used tool to diagnose very common and sometimes limb-threatening bone infections in persons with diabetes may not be as reliable as many once believed, based on a recent study by a transatlantic team of researchers. The study, published to the Web ahead of print in February's edition of the journal Diabetes Care, longitudinally evaluated a large sample of persons with diabetes with wounds, and tested the commonly performed “probe to bone” test. The test, which uses a sterile instrument to feel for bone inside a wound, has been thought by many to be highly predictive of bone infection.

“It certainly makes sense that if you can feel bone, then it must be infected,” noted David G. Armstrong, DPM, PhD, Professor of Surgery at Scholl's Center for Lower Extremity Ambulatory Research (CLEAR) at Rosalind Franklin University of Medicine and Science, and a co-investigator on the study. “Unfortunately, though, this doesn't always seem to be the case. The test, if used by itself in a normal clinical setting, isn't much better than flipping a coin. We therefore recommend it be used with other aids, such as biopsy or appropriate imaging tools.”