Bone and Joint Infections: The Role of Imaging in Tailoring Diagnosis to Improve Patients' Care

Abstract

Imaging is needed for the diagnosis of bone and joint infections, determining the severity and extent of disease, planning biopsy, and monitoring the response to treatment. Some radiological features are pathognomonic of bone and joint infections for each modality used. However, imaging diagnosis of these infections is challenging because of several overlaps with non-infectious etiologies. Interventional radiology is generally needed to verify the diagnosis and to identify the microorganism involved in the infectious process through imaging-guided biopsy. This narrative review aims to summarize the radiological features of the commonest orthopedic infections, the indications and the limits of different modalities in the diagnostic strategy as well as to outline recent findings that may facilitate diagnosis.

Keywords: bone infections; diagnosis; imaging; prosthesis infections.

Figure 1

Staphylococcus aureus Osteomyelitis in a 20-year-old man. A conventional radiograph (A). MRI coronal T1w (B) and axial T2w fat-saturated (C) show a permeative lesion of the left femoral shaft. CT-guided biopsy permitted to identify the responsible microorganism (D). Conventional radiograph after surgical treatment showed antibiotic microspheres placed into the bone (E).

Figure 2

Septic arthritis of the right hip in a 78 years old woman with studied with x-rays (A), CT (B,F), and MRI (C,D,E). CT showed bone intramedullary air coefficients (broken arrows) and involvement of the homolateral ileo-psoas muscle (arrows).

Figure 3

Chronic osteomyelitis of the tibia in a 16-year-old female. Periosteal reaction and sclerotic intramedullary focus are detectable on conventional radiography (A) and CT scan (B). MRI showed ill-defined bone edema among the sclerotic intramedullary changes on STIR coronal (C) and T1w sagittal (D).

Figure 4

Brodie’s abscess in a 30-year-old man. Computed tomography of the pelvis showed a small (1.5 cm) radiolucent lesion with thick and irregular sclerotic margins (arrow).

Figure 5

Pyogenic bifocal spondylodiscitis (T8-T9 and L1-L2) in a 70-year-old woman. FDG PET-CT showed increased SUV on both vertebral levels (arrows).

Figure 6

Tuberculous spondylodiscitis (T12-L2) in an 84-year-old woman. MRI detects bone and disks involvement together with several voluminous paravertebral abscesses (arrows).

Figure 7

Chronic recurrent multifocal osteomyelitis (CRMO) in an 11-year-old boy. MRI shows several areas of bone edema in thoracic, lumbar, and sacral vertebral bodies (arrows). After a CT-guided bone biopsy of S1, the diagnosis of exclusion was CRMO.