BACKGROUND: This study aimed to demonstrate how much examination findings and laboratory values can be helpful in the diagnosis of osteomyelitis in patients with diabetic foot infections. MATERIAL/METHODS: Data of 46 consecutive inpatients prospectively followed up according to a specially designed "Diabetic Foot Follow-up Form" were analyzed. Following diagnostic interventions, clinical and laboratory findings of patients with and without a diagnosis of osteomyelitis were compared. In these patients with and without osteomyelitis confirmed by histopathology and/or microbiology and/or MRI the sensitivity and specificity of ESR (erythrocyte sedimentation rate) and wound size were also determined. RESULTS: There was no significant differences in the duration of diabetes or the existence of nephropathy or vascular disease, while the other findings (ESR, C-reactive protein, wound size, history of diabetic foot ulcer, and retinopathy) were significantly different. It is found that ESR > or =65 mm/h together with a wound size > or =2 cm2 had a sensitivity of 83%, specificity of 77%, positive predictive value of 80%, and negative predictive value of 81% in the diagnosis of osteomyelitis. CONCLUSIONS: This study demonstrated that simple clinical evaluation and laboratory findings without using expensive imaging methods may be important indicators of osteomyelitis.