Most common area involved in tubercular spine is:

Ans. (a) Para-discal AreaRef: Maheshwari 8th ed. /185* Most common site of skeletal tuberculosis: TB Spine (50% of cases)* Most common site in spine: Thoraco Lumbar vertebra followed by cervical vertebra (Thoracic vertebra > Lumbar)* The spinal TB is always secondary to a primary lesion (ex: in lungs) and occurs due to hematogenous spread.* IOC for TB spine: MRIClinically there are four types of Pott's Spine* Para discal lesion(most common) begins in the metaphysis, erodes the cartilage and destroys the disc, resulting in narrowing of the disc space.* Central type begins in the midsection of the body which further gets softened under gravity and muscle action, leading to compression, collapse and bony deformation.* Anterior lesions lead to cortical bone destruction beneath the anterior longitudinal ligament. Spread of the infection is in the subperiosteal and sub ligamentous planes resulting in the loss of periosteal blood supply to the body with resultant collapse.* In appendide type, the infection settles in the pedicles, the laminae, the articular processes or the spinous processes and causes initial ballooning of the structure followed by destruction.