<prompt> Potts spine is commonest in spine -CevicalThoracicLumbarSacral  <response>: Potts Spine Tubercular spondylitis has been documented in ancient mummies from Egypt and Peru and is one of the oldest demonstrated disease.Percival Pott presented the classic description of spinal TB in 1779. Spinal TB constitutes about 50 of all cases of osteoaicular TB. MC site: Lower thoracic and lumber region followed by middle thoracic and cervical veebrae. Paradiscal Commonest type Spread through aerial supply Bacteria lodge in the contiguous areas of two adjacent veebrae 4 granulomatous inflammation leading to erosion of veebral margins -loss of nutrition of interveebral disc -Disc degeneration When the interveebral discs have been completely destroyed,the adjacent bodies fuse with each other. Central Lesions Body of single veebra is affected. Stas in the centre of the veebral body. Infection at this site probably reaches through Batson;s venous or branches of post.veebral ary. Lytic area develops in the centre of veebral body leading to balooning of veebral body mimicking tumour Later stages-concentric collapse resembling Verebra Plana. Disc space is notminimally affected Clinical Features Constitutional symptoms,such as fever, night sweats,loss of weight and appetite may occur before symptoms related to spine. 1. Pain-can be -Localised to the siteMC early symptoms - Radicular -worsen with activity and at nightnight cries 2. Stiffness -Protective mechanism of body where paraveebral muscle go into spasm to prevent movement at the affected veebra. 3. Cold abcess - Patient may present the first time with swellingcold abcess or due to its compression effects:- Retropharyngeal abscess --Dysphagia,dyspnea, Hoarseness of voice Mediastinal abscess --Dysphagia Psoas abscess -- Flexion deformity of hip -No usual signs of inflammation like heat ,redness etc. -Follows paths of least resistance along facial planes,blood vassels nerves. REF :MAHESWARI 9TH ED 