Welcome to the Podiatry Arena forums, for communication between foot health professionals about podiatry and related topics.
You are currently viewing our podiatry forum as a guest which gives you limited access to view all podiatry discussions and access our other features. By joining our free global community of Podiatrists and other interested foot health care professionals you will have access to post podiatry topics (answer and ask questions), communicate privately with other members (PM), upload content, view attachments, receive a weekly email update of new discussions, earn CPD points and access many other special features. Registered users do not get displayed the advertisments in posted messages. Registration is fast, simple and absolutely free so please, join our global Podiatry community today!
If you have any problems with the registration process or your account login, please contact contact us.
Probe-to-Bone Test for Diagnosing Diabetic Foot Osteomyelitis
Reliable or relic?
Lawrence A. Lavery, David G. Armstrong, Edgar J.G. Peters and Benjamin A. Lipsky Diabetes Care 30:270-274, 2007
Quote:
OBJECTIVE—We sought to assess the accuracy of the probe-to-bone (PTB) test in diagnosing foot osteomyelitis in a cohort of diabetic patients with bone culture proven disease.
RESEARCH DESIGN AND METHODS—In this 2-year longitudinal cohort study, we enrolled 1,666 consecutive diabetic individuals who underwent an initial standardized detailed foot assessment, followed by examinations at regular intervals. Patients were instructed to immediately come to the foot clinic if they developed a lower-extremity complication. For all patients with a lower-extremity wound, we compared the results of the PTB test with those of a culture of the affected bone. We called PTB positive if the bone or joint was palpable and defined osteomyelitis as a positive bone culture.
RESULTS—Over a mean of 27.2 months of follow-up, 247 patients developed a foot wound and 151 developed 199 foot infections. Osteomyelitis was found in 30 patients: 12% of those with a foot wound and 20% in those with a foot infection. When all wounds were considered, the PTB test was highly sensitive (0.87) and specific (0.91); the positive predictive value was only 0.57, but the negative predictive value was 0.98.
CONCLUSIONS—The PTB test, when used in a population of diabetic patients with a foot wound among whom the prevalence of osteomyelitis was 12%, had a relatively low positive predictive value, but a negative test may exclude the diagnosis.
Re: Probe-to-Bone Test for Diagnosing Diabetic Foot Osteomyelitis
The initial probe to bone data was based on a population group that had extremely high likelihood of having osteomyelitis - it was not meant to suggest that if you can probe to bone it is osteomyelitis. However, if you think that there is a high index suspicion that osteomyelitis is present and you can probe to bone, then there is a greater chance that you are right. Higher index of suspician = longer duration of wound, previous history of infection etc...
The interpretation of the initial study results has changed over the years - deviating from the original authors conclusion, simply because other authors citing this work have interpreted the results in different ways - I know that a lot of practitioners think that osteomyelitis is present as soon as bone is exposed, when it may not be the case. It makes you think about checking where people got their initial information from to make sure their interpretation is appropriate.....just a thought....
Probe-to-Bone Test for Diagnosing Diabetic Foot Osteomyelitis
Linear Mode
