Continuing Education Column Imaging Diagnosis of Osteoporotic Fracture Seoung -Oh Yang, MD Department of Radiology, Eulji University College of Medicine E - mail : soyang@eulji.ac.kr Sungjun Kim, MD Department of Radiology, Yonsei University College of Medicine Seon-Kwan Juhng, MD Department of Radiology, Wonkwang University College of Medicine J Korean Med Assoc 2010; 53(1): 67-75 Abstract Osteoporotic vertebral fractures suspected at clinical evaluation require radiological confirmation. Most radiologists make the diagnosis of vertebral fracture on the basis of a qualitative impression. However, unlike other fractures, vertebral fractures are commonly found on radiographs obtained for other reasons in patients who do not show signs or symptoms suggestive of fractures. Radiologists qualitatively analyze radiographs of the thoracolumbar spine to identify vertebral fractures in patients whose clinical indications suggest trauma, osteoporosis, malignancy, or acute back pain. The accuracy of decision-making process can be enhanced by additional radiographic projections or by complementary examinations including DXA (Dual Energy X-ray Absorptiometry) morphometry, bone scan, CT, or MRI. The importance of imaging is highlighted by the fact that only about one in four vertebral fractures is recognized on the basis of clinical evaluations without radiographs. Radiographs may include lateral and AP (anterior/posterior) X-rays of the affected spinal segments. The physician may request bone scan and/or CT to help identify the location of the fracture, its status (stable versus unstable). Furthermore, an MRI scan may be performed if neurologic deficit, soft tissue trauma or hematoma are suspected. Keywords: Osteoporosis; Vertebral fracture; Imaging diagnosis 67
Yang SO Kim SJ Juhng SK Table 1. Osteopenia score for vertebrae by Saville index 1 3 2 4 Figure 1. Diagram of Saville index (Insurance covered from Grade 3). Radiographic appearance of vertebra 0 Normal bone density 1 Minimal loss of density: endplates begin to stand out, giving a stencilled effect 2 Vertical striation is more obvious; endplates are thinner 3 More severe loss of bone density than grade 2; endplates becoming less visible 4 Ghost-like vertebral bodies; density is no greater than soft tissue; no trabecular pattern is visible Figure 2. Various type of vertebral compression fractures: From left, wedge type, biconcave type, and pancake -like crushed vertebral fracture. 68
Imaging Diagnosis of Osteoporotic Fracture Figure 3. Semiquantitative method to assess vertebral fractures. (Genant HK, et al. J Bone Mineral Res 1993; 8(9):1137-1148). Figure 4. AP and lateral images of DXA vertebral morphometry. 69
Yang SO Kim SJ Juhng SK Figure 5. Compression fracture of the 1st lumbar vertebral body by bone scan (left) and sacral insufficiency fracture by bone SPECT (right). Figure 6. CT sagittal reconstructed image and 3 D reformation of L2 vertebral fracture in 62 year-old male. 70
Imaging Diagnosis of Osteoporotic Fracture Figure 7. MRI finding of benign vertebral fracture: T2 WI, T1 WI, T1 contrast enhanced image (from left). Figure 8. MRI finding of malignant vertebral fracture: T2 WI, T1 WI, T1 contrast enhanced image (from left). Note the exophytic soft tissue mass and signal changes in the whole spine. 71
Yang SO Kim SJ Juhng SK Figure 9. MRI finding of sacral insufficiency fracture: Fat suppressed sagittal T2 WI, axial T1 WI, axial fat suppressed T1 WI (from left). 72
Imaging Diagnosis of Osteoporotic Fracture Figure 10. Simple radiographs of two cases with multiple myeloma: Heterogenous osteolytic bone loss and biconcave fractures. Figure 11. Simple radiographs of osteomalacia: See the apparent vertebral end-plates with fuzzy appearance. 73
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