Clinical Diagnosis Versus Plain Radiography for Diabetic Foot Osteomyelitis: A Prospective Study of Diagnostic Agreement in a Resource‐Limited Settings

ABSTRACT

Diabetic foot osteomyelitis (DFO) is a serious complication of diabetic foot ulcers, particularly in advanced infections. In low‐resource settings, access to medical imaging may be limited. This study evaluated the diagnostic agreement between a composite clinical approach (clinical assessment plus probe‐to‐bone test) compared with plain radiography for diagnosing DFO, including performance across ulcer categories. A prospective cohort study was conducted from December 2021 to January 2025 among patients with suspected DFO. Participants underwent clinical evaluation, risk factor assessment, ulcer history, SINBAD classification, probe‐to‐bone testing and plain radiography. Diagnostic performance measures were calculated. Given the absence of a gold standard reference test (bone biopsy) in this low‐resource setting, performance measures represent comparative diagnostic agreement with plain radiography rather than absolute diagnostic accuracy. A total of 166 patients with deep foot ulcers were enrolled. Composite clinical diagnosis identified osteomyelitis in 117 patients and excluded it in 49. Plain radiography was positive in 96 of 117 composite positive cases, while 21 were discordant; all 49 composite negative cases were radiographically negative. The composite approach showed 100% sensitivity, 70% specificity and 87.3% overall agreement. Sensitivity remained 100% across ulcer categories, while specificity increased significantly from 63.8% in SINBAD‐4 ulcers to 77.8% in SINBAD‐5 ulcers, improving agreement from 86.1% to 89.7%. In conclusion, composite clinical diagnosis demonstrates substantial agreement with plain radiography in this cohort of patients with suspected DFO. This can provide a practical adjunct for clinical assessment in resource‐limited settings where imaging is unavailable or difficult to interpret but should not be considered a definitive diagnostic test in the absence of an independent reference standard.