Imaging of Fracture-related Infections (IFI)

Rationale: Infections after traumatic injuries and subsequent fracture treatment have major impact on the patient’s personal life in terms of multiple re-operations, long-term antibiotic treatment, immobilization, inability to work and restrictions to participate in social activities. Unfortunately, there is no consensus about which diagnostic technique (WBC-scintigraphy, FDG-PET/CT or MRI) is most accurate in detecting or ruling out fracture-related infections. Accurate diagnosis of an infection is important for the clinical decision making in order to determine the optimal surgical strategy.

Primary objective: Determining the overall diagnostic performances of WBC scintigraphy, FDG-PET/CT and MRI in patients with suspected fracture-related infections and establish the most accurate imaging strategy for diagnosing (or excluding) fracture-related infections.

Study population: Patients who need additional diagnostic imaging, according to the standard of care, based on a clinical suspicion of an infection (e.g. infected non-union or chronic posttraumatic osteomyelitis) following surgical fracture treatment.

Study design: All patients included in this prospective cohort study will undergo three imaging techniques, namely a WBC scintigraphy, an FDG-PET/CT, and an MRI, to determine the most accurate imaging strategy for diagnosing fracture-related infections. This study won’t influence the standard of care for these patients.

Main study parameters/endpoints: The diagnostic accuracy of all different imaging modalities (sensitivity, specificity, positive predictive value and negative predictive value) will be calculated.

Determining the overall diagnostic performances of WBC scintigraphy, FDG-PET/CT and MRI in trauma patients with suspected fracture-related infections and establish the most accurate imaging strategy for diagnosing (or excluding) fracture related infections.

Diagnostics:

T=0: WBC scintigraphy, FDG-PET/CT, MRI

The golden standard for the final diagnosis whether there is a fracture-related infection or not will be based on the result of at least 5 intra-operative sampled microbiology cultures or (in case of no surgery) the clinical presence or absence of infection as judged by a trauma or orthopaedic surgeon (treating physician) at 1 year follow-up.

Functional outcome:

- T=0, 3, 6, 12 months, 1.5, 2 years: EQ-5D, SMFA

Cost analysis:

- T=0, 3, 6, 12 months, 1.5, 2 years: iMTA PCQ and iMTA MCQ questionnaires

All patients, who will be enrolled in the IFI trial, will undergo three imaging techniques, namely a WBC scintigraphy, an FDG-PET/CT and an MRI, in order to determine the most accurate imaging strategy for diagnosing fracture-related infections. The diagnostic accuracy of all three imaging modalities (WBC scintigraphy, FDG-PET/CT, and MRI) will be determined with as reference the golden standard for the final diagnosis of a fracture-related infection.The golden standard for the final diagnosis whether there is a fracture-related infection or not will be based on the result of at least 5 intra-operative sampled microbiology cultures or (in case of no surgery) the clinical presence or absence of infection as judged by a trauma or orthopaedic surgeon (treating physician) at 1 year follow-up.