Commonest presenting symptom of Pott's spine is: March 2007

Ans. B: Back Pain Tuberculosis (TB) of the spine (Pott's disease) is the most common site of bone infection in TB. The lower thoracic and upper lumbar veebrae are the areas of the spine most often affected. Pott's disease results from haematogenous spread of tuberculosis from other sites, often pulmonary. The infection then spreads from two adjacent veebrae into the adjoining disc space. If only one veebra is affected, the disc is normal, but if two are involved the interveebral disc, which is avascular, cannot receive nutrients and collapses (seen as narrowing of interveebral space on X-rays) The disease progresses slowly. Signs and symptoms include: Localised back pain is the earliest and commonest complaint Paraveebral swelling may be seen Neurological signs may occur, leading to paraplegia. Stiffness Deformity Constitutional symptoms Spinal X-ray may not show early disease as 50% of bone mass must be lost for changes to be visible on x-ray. However, plain radiographs can show veebral destruction and narrowed disc space. MRI is useful to demonstrate the extent of spinal compression and can show changes at an earlier stage than plain radiographs. Bone elements visible within the swelling, or abscesses, are strongly indicative of Pott's disease as opposed to malignancy. CT scans and nuclear bone scans can also be used.