The impact of magnetic resonance imaging in the diagnostic and classification process of osteoporotic vertebral fractures.

Introduction: Standard radiographs are still considered as the gold standard for the early assessment of thoraco-lumbar osteoporotic vertebral fractures (OVFs), although several studies demonstrated superior accuracy of magnetic resonance imaging (MRI) in the diagnostic process of OVFs. The aim of this study was to quantify the misdiagnosis rate of OVFs and analyse the impact of MRI on early diagnosis and classification, compared to standard radiographs alone.

Materials And Methods: A total of 173 patients were enrolled in this study. All participants were 55 years of age or older (60 years for men) and complained acute back pain with suspected thoracolumbar OVFs without history of high-energy trauma. Diagnosis of OVF was initially performed on standard radiographs obtained in the emergency room. Then, all the patients underwent MRI scan with short-tau inversion recovery (STIR) sequencing within 7 days. We compared the level and number of fractures identified on standard radiographs with the MRI scan results. The discordance between radiographic and MRI diagnosis was quantified. Fractures were classified according to AO Spine Classification.

Results: Mean age of the study participant was 74.2 years (range 55-92). They were 100 males and 73 females. MRI modified initial diagnosis in 52% (90/173) of our patients: in 43.9% of patients MRI identified one or more new thoracolumbar fracture. In 14 cases (8.1%) MRI disproved the evidence of any thoracolumbar fracture, even those recognized at plain X-rays. Bone bruise was detected by MRI in 19 vertebral bodies in 8 patients (4.6%) at levels that were classified as unremarkable on X-ray alone. In addition, 63 patients (36.4%) presented a total of 93 old fractures. The classification of fracture pattern after MRI changed in 28.90% of the patients (changes mostly involved AO type A1 patterns).

Conclusions: Underdiagnosis of osteoporotic vertebral fractures is a common problem due to a lack of radiographic detection. Our results showed that the extensive use of MRI imaging allows better accuracy in the diagnostic process and in the classification assessment, compared to conventional radiographs. Further investigation should provide additional information about the impact of early MRI on treatment and management of elderly patients with suspected OVFs, including the decision to hospitalize or not, and how it could affect clinical outcome and social costs.