Spinal tuberculosis is a destructive form of tuberculosis. Musculoskeletal affection is observed in 4% of all cases with tuberculosis; 50% of which involve the spine. Spinal tuberculosis is more common in children and young adults. The incidence of spinal tuberculosis is increasing in developed nations. Genetic susceptibility to spinal tuberculosis has recently been demonstrated. Characteristically, there is destruction of the intervertebral disc space and the adjacent vertebral bodies, collapse of the spinal elements, and anterior wedging leading to kyphosis and gibbus formation.

Pott’s paraplegia is caused by a bacteria called Mycobacterium tuberculosis.

The Thoracic region of vertebral column is most frequently affected. Formation of a ‘cold’ abscess around the lesion is another characteristic feature. The incidence of multi-level noncontiguous vertebral tuberculosis occurs more frequently than previously recognized.

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Common clinical manifestations include constitutional symptoms like fever, weight loss etc. Neurological features include back pain, spinal tenderness, paraplegia, and spinal deformities. A typical presentation of tuberculosis of the spine consists of pain during movement with a localized deformity in the back that is tender following percussion as well as other typical systemic symptoms of active tuberculosis (i.e., night cries, malaise, weight loss, loss of appetite, night sweats, and a rise in temperature in the evening). Moreover, patients may or may not have a neurological deficit, which can be the first symptom in rare cases.

Mycobacterium tuberculosis culture is the gold standard method for the diagnosis of tuberculosis, but it also has various limitations, including a required 6–8 week period of growth because of the slow replication rate of the bacteria; these results are often negative as it requires 10–100 bacilli/mL (live bacilli) in clinical specimens to achieve culture positive results.

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Magnetic Resonance Imaging (MRI) is a better diagnostic method than radiography. Marrow edema, endplate disruption, paravertebral soft tissue formation, subligamentous collections, and a high signal of the intervertebral disc on T2-weighted are typical MRI features with good to excellent sensitivity for spinal tuberculosis. For the diagnosis of Spinal tuberculosis Magnetic Resonance Imaging is more sensitive imaging technique than x-ray and more specific than Computed Tomography. Magnetic Resonance imaging frequently demonstrates involvement of the vertebral bodies on either side of the disk, disc destruction, cold abscess, vertebral collapse, and presence of vertebral column deformities.

An accurate clinical diagnosis of tuberculosis of the spine requires an extremely high degree of clinical suspicion as one in every three patient can exhibit an atypical clinical presentation. Atypical presentation primarily includes discrete foci of spinal involvement with intervening normal vertebrae and no evidence of a connecting soft tissue abscess or any other MRI features typical of tuberculosis as discussed above (i.e., the involvement of only the posterior column of the spine without end plate involvement and multiple skip lesions without a soft tissue shadow). Neuroimaging-guided needle biopsy from the affected site in the center of the vertebral body is the gold standard technique for early histopathological diagnosis.

A culture of acid-fast bacilli in Osteoarticular tuberculous lesions remains the gold standard diagnostic test, but it is far from being an ideal screening tool to diagnose Spinal tuberculosis because of its low sensitivity.

Recent techniques, such as Polymerase Chain Reaction (PCR) and GeneXpert provide improved accuracy over microscopy and are more rapid than bacterial cultures. The GeneXpert test has a sensitivity of 95.6% and a specificity of 96.2% for diagnosis of Spinal tuberculosis. GeneXpert is also more likely to detect Mycobacterium tuberculosis DNA than traditional PCR, with the added advantage of also determining Rifampicin resistance. Rifampicin is a first line antitubercular drug.

Antituberculous treatment remains the cornerstone of treatment. Surgery may be required in selected cases, e.g. large abscess formation, severe kyphosis, an evolving neurological deficit, or lack of response to medical treatment.

With early diagnosis and early treatment, prognosis is generally good. Medical management results in clinical improvement in a majority of the patients of spinal tuberculosis. Disability in Potts paraplegia is evaluated with modified Barthel index (MBI) at six months of follow up.

Outcome is defined as good (MBI > 12) and poor (MBI ≤ 12). On univariate analysis, duration of illness more than 6 months, bladder involvement, spinal deformity, spastic paraparesis, and flexor spasms are important clinical predictors of poor outcome. Involvement of more than two vertebrae, complete collapse, cord compression, spinal extension of the abscess, and thick/septate abscess wall are the neuroimaging parameters associated with poor prognosis.