DOI: 10.1007/s00259-016-3528-9Pages: 432-440

[18F]FDG PET accurately differentiates infected and non-infected non-unions after fracture fixation

1. University of Munich, Department of Nuclear Medicine

2. University of Munich, Institute for Clinical Radiology

3. BG Trauma Center Murnau, Department of Reconstructive Arthroplasty

4. PMU Salzburg, Paracelsus Medical University

5. University of Vienna, Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Therapy

Correspondence to:
Marcus Hacker
Email: marcus.hacker@meduniwien.ac.at

Close

Abstract

Purpose

Complete fracture healing is crucial for good patient outcomes. A major complication in the treatment of fractures is non-union. The pathogenesis of non-unions is not always clear, although implant-associated infections play a significant role, especially after surgical treatment of open fractures. We aimed to evaluate the value of [18F]FDG PET in suspected infections of non-union fractures.

Methods

We retrospectively evaluated 35 consecutive patients seen between 2000 and 2015 with suspected infection of non-union fractures, treated at a level I trauma center. The patients underwent either [18F]FDG PET/CT (N = 24), [18F]FDG PET (N = 11) plus additional CT (N = 8), or conventional X-ray (N = 3). Imaging findings were correlated with final diagnosis based on intraoperative culture or follow-up.

Results

In 13 of 35 patients (37 %), infection was proven by either positive intraoperative tissue culture (N = 12) or positive follow-up (N = 1). [18F]FDG PET revealed 11 true-positive, 19 true-negative, three false-positive, and two false-negative results, indicating sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 85 %, 86 %, 79 %, 90 %, and 86 %, respectively. The SUVmax was 6.4 ± 2.7 in the clinically infected group and 3.0 ± 1.7 in the clinically non-infected group (p <0.01). The SUVratio was 5.3 ± 3.3 in the clinically infected group and 2.6 ± 1.5 in the clinically non-infected group (p <0.01).

Conclusion

[18F]FDG PET differentiates infected from non-infected non-unions with high accuracy in patients with suspected infections of non-union fractures, for whom other clinical findings were inconclusive for a local infection. [18F]FDG PET should be considered for therapeutic management of non-unions.

This article is freely available, click here to access the full text/PDF

  • Accepted: Sep 13, 2016
  • Online: Oct 5, 2016

Article Tools

eanm
EJNMMI Ad