Accuracy of diagnostic imaging modalities for peripheral post-traumatic osteomyelitis - a systematic review of the recent literature

Abstract

Aims: Post-traumatic osteomyelitis (PTO) is difficult to diagnose and there is no consensus on the best imaging strategy. The aim of this study is to present a systematic review of the recent literature on diagnostic imaging of PTO.

Methods: A literature search of the EMBASE and PubMed databases of the last 16 years (2000-2016) was performed. Studies that evaluated the accuracy of magnetic resonance imaging (MRI), three-phase bone scintigraphy (TPBS), white blood cell (WBC) or antigranulocyte antibody (AGA) scintigraphy, fluorodeoxyglucose positron emission tomography (FDG-PET) and plain computed tomography (CT) in diagnosing PTO were considered for inclusion. The review was conducted using the PRISMA statement and QUADAS-2 criteria.

Results: The literature search identified 3358 original records, of which 10 articles could be included in this review. Four of these studies had a comparative design which made it possible to report the results of, in total, 17 patient series. WBC (or AGA) scintigraphy and FDG-PET exhibit good accuracy for diagnosing PTO (sensitivity ranged from 50-100%, specificity ranged from 40-97% versus 83-100% and 51%-100%, respectively). The accuracy of both modalities improved when a hybrid imaging technique (SPECT/CT & FDG-PET/CT) was performed. For FDG-PET/CT, sensitivity ranged between 86 and 94% and specificity between 76 and 100%. For WBC scintigraphy + SPECT/CT, this is 100% and 89-97%, respectively.

Conclusions: Based on the best available evidence of the last 16 years, both WBC (or AGA) scintigraphy combined with SPECT/CT or FDG-PET combined with CT have the best diagnostic accuracy for diagnosing peripheral PTO.

Keywords: Antigranulocyte antibody scintigraphy; CT scan; Diagnostic imaging; FDG-PET; Fracture; Fracture related infection; MRI; Open reduction and internal fixation (ORIF); Osteosynthetic material; Ostheosynthesis; Post-traumatic osteomyelitis; White blood cell scintigraphy.

Fig. 1

PRISMA Flow diagram

Fig. 2

Clinical example of WBC scintigraphy + SPECT/CT. A 37-year-old man with a grade 3A complicated distal humeral fracture of the left elbow, initially treated with an external fixator and subsequently by plate osteosynthesis of the distal humerus. c X-ray: situation after recent fixation of the fracture with plate osteosynthesis, no signs of loosening or infection. After 4 months, he presented with a fistula and a clinical suspicion of osteomyelitis of the distal humerus. a–b, d–e: WBC scintigraphy (a image at 4 hours, b image at 24 hours, d–e fusion SPECT/CT images) after the injection of 220 MBq 99 m-Tc-labeled leucocytes demonstrated an infection around the implant at the lateral side of the elbow/distal screw. The low uptake points to only a low-grade appearance and the location to soft tissue involvement; this was confirmed at operation (f clinical pre-operative picture, g perioperative clinical picture)

Fig. 3

Clinical example of FDG-PET/CT. A 77-year-old woman who had a proximal femur fracture for which she underwent open reduction and internal fixation with a femur plate which had to be removed at a later stage due to infection. a X-ray, AP view: no consolidation, severe angulation, heterogeneous sclerotic aspect around the fracture. She was referred to our hospital with a fistula in the lateral thigh and a clinical suspicion of osteomyelitis of the proximal femur. Further imaging demonstrated an infection of the proximal femur, a medial abscess and a fistula coursing to the lateral aspect of the thigh which correlated with the clinical findings during surgery. b–f ¹⁸F FDG-PET/CT (b coronal FDG-PET image, c coronal fused FDG-PET/CT image, d–f transaxial fused FDG-PET/CT images). g clinical pre-operative picture, h perioperative clinical picture

Fig. 4

Clinical example of MRI. A 54-year-old man with a history of an open fracture treated with a plate many years ago. The fracture healed slowly and then the plate was removed because of continued skin breakdown over the front of the tibia. a Frontal and lateral radiograph demonstrating sclerosis and chronic periosteal reaction around the previous fracture site. b Sagittal fat-suppressed images of the calf demonstrating bone and soft tissue oedema. c & d Axial fat-suppressed images demonstrating sequestra (blue arrow), cortical abscesses (yellow arrows) and periostitis and soft tissue oedema (red arrow)