Pott′s spine: Diagnostic imaging modalities and technology advancements

Spinal tuberculosis (TB) or Pott's spine is the commonest extrapulmonary manifestation of TB. It spreads through hematogenous route. Clinically, it presents with constitutional symptoms, back pain, tenderness, paraplegia or paraparesis, and kyphotic or scoliotic deformities. Pott's spine accounts for 2% of all cases of TB, 15% of extrapulmonary, and 50% of skeletal TB. The paradiscal, central, anterior subligamentous, and neural arch are the common vertebral lesions. Thoracic vertebrae are commonly affected followed by lumbar and cervical vertebrae. Plain radiographs are usually the initial investigation in spinal TB. For a radiolucent lesion to be apparent on a plain radiograph there should be 30% of bone mineral loss. Computed tomographic scanning provides much better bony detail of irregular lytic lesions, sclerosis, disc collapse, and disruption of bone circumference than plain radiograph. Magnetic resonance imaging (MRI) is the best diagnostic modality for Pott's spine and is more sensitive than other modalities. MRI frequently demonstrates disc collapse/destruction, cold abscess, vertebral wedging/collapse, marrow edema, and spinal deformities. Ultrasound and computed tomographic guided needle aspiration or biopsy is the technique for early histopathological diagnosis. Recently, the coexistence of human immunodeficiency virus infections and TB has been increased globally. In recent years, diffusion-weighted MRI (DW-MRI) and apparent diffusion coefficient values in combination with MRI are used to some extent in the diagnosis of spinal TB. We have reviewed related literature through internet. The terms searched on Google scholar and PubMed are TB, extrapulmonary TB, skeletal TB, spinal TB, Pott's spine, Pott's paraplegia, MRI, and computed tomography (CT).