Skeletal Tuberculosis

Thoracolumbar REF: Apley 387-389, S M Tuli 3^rd edition page 192

• Most common site of skeletal tuberculosis is spine followed by hip and knee

SPINE (50%) > HIP > KNEE

• Commonest spine involved in spine TB is Thoracolumbar/Dorsolumbar T12-L1 (Lower thoracic to be precise)

LOWER THORACIC > LUMBAR > UPPER THORACIC

• Paraplegia due to pott’s spine most commonly involves upper thoracic vertebrae as in upper thoracic vertebrae there is more acute kyphosis, spinal canal is narrow and spinal cord is relatively large.
• First symptom of TB spine is “Pain on movement”
• Commonest symptom of TB spine is “Back pain”

Prognostic factors in Pott’s paraplegia

• Age of the patient: Children respond to the treatment better than adults
• Duration of the paraplegia: Long standing paraplegia has a worse prognosis
• Severity: Motor paralysis alone has a better prognosis. Sphincter involvement i.e urinary or bowel incontinence are bad prognostic indicators.
• Onset of paraplegia: Acute onset paraplegia has a better prognosis
• Sudden onset of paraplegia: has a bad prognosis

• Complete cord involvement
• Late onset
• Longer duration > 12 months
• Older age
• Healed vertebral lesion
• Kyphotic deformity > 60 degree
• MRI finding: Myelomalacia syringomyelia

Ans. is ‘a’ i.e., Pott’s spine

• T-spine swelling causes paravertebral abscess which may further lead to Pott’s paraplegia, mediastinal abscess, Lumbar abscess.

• Chronic retropharyngeal abscess is associated with caries of cervical spine or tuberculous infection of retropharyngeal lymph nodes secondary to tuberculosis of deep cervical nodes (i.e. suppuration of Rouviere nodes)
• It leads to discomfort in throat, dysphagia, fluctuant swelling of postpharyngeal wall.
• Retropharyngeal abscess does not lead to psoas spasm.

Treatment

• Incison and drainage of abscess
• Full course of ATT 

Ans. A i.e. Tuberculosis

• MC site of skeletal TB: Vertebrae
• In Spine, TB starts in: Vertebral body
• MC region involved in spinal TB: T9-L1
• Earliest symptom of spinal TB: Pain
• Earliest X-ray sign in Pott’s disease: Narrowing of disc space

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 vertebrae 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 vertebrae into the adjoining disc space.

If only one vertebra is affected, the disc is normal, but if two are involved the intervertebral disc, which is avascular, cannot receive nutrients and collapses (seen as narrowing of intervertebral space on X-rays)

The disease progresses slowly. Signs and symptoms include:

• Localised back pain is the earliest and commonest complaint
• Paravertebral 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 vertebral 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.

Ans. B: Blood

Ans. C: Spine

It is named after Percivall Pott.

The lower thoracic and upper lumbar vertebrae are the areas of the spine most often affected.

Scientifically, it is called tuberculous spondylitis and it is most commonly localized in the thoracic portion of the spine.

Pott’s disease results from haematogenous spread of tuberculosis from other sites, often pulmonary. The infection then spreads from two adjacent vertebrae into the adjoining intervertebral disc space.

Ans. B: Narrowing of disc space

Reduction of the disc space is the earliest sign in the commoner, paradiscal type of tuberculosis

Skeletal TB:

• Earliest symptom of spinal TB: Back pain
• Earliest sign in Pott’s disease: Narrowing of disc space
• MC vertebrae to be involved in TB spine: T9-T12
• TB spine starts in: Vertebral body (paradiscal)
• Spina ventosa: TB dactylitis

Ans. Marked osteoblastic response

Ans. is ‘d’ i.e., Progression to kyphosis deformity is least with lumbar lesions

Tuberculosis in children

Extra-pulmonary tuberculosis accounts for 5 – 10% of total cases of tuberculosis in children o About 1/3 of children with tuberculosis have extrapulmonary tuberculosis

The most common mode of presentation in a child less than 2 years is development of a gibbusof the dorsal area. o Under the age of four, backache in children should be regarded as pathological unless and until proved otherwise. o MRI cannot differentiate between pyogenic or tuberculous infection.

Vertebral tuberculosis is the most common form of skeletal tuberculosis in children, accounting for 50% of all cases in reported series. Approximate distribution in the skeleton are spine (50%), hip (20%), knee (10%), ankle and foot (5%), hand and wrist (3%), elbow (2%), shoulder (1 %), bursal sheaths and other bones (8%)

The thoracic spine is most commonly affected; the radiological features include bone marrow oedema and enhancement, posterior element involvement, canal stenosis, and spinal cord or nerve root compression. Inter-vertebral disc enhancement, vertebral collapse and kyphosis deformity are particularly suggestive of tuberculosis.

Those with dorsal lesions have maximal deformity at the time of presentation, partly due to the additive effect of the normal thoracic kyphosis. However, the rib cage offers protection against additional collapse. Patients with dorsolumbar lesions have the worst prognosis as they tend to collapse more during the active phase of the disease and even more during the growth period. Those with lumbar lesions have the best prognosis with the least deformity at presentation, a lesser increase during the active phase, and also a tendency for substantial decrease during the growth period.

Ans. is `c’ i.e., Exagrated lumbar lordosis

Clinical features of TB of spine

• The disease is commonest in young adults.
• The presenting complains are : –

1. Back pain : Commonest and earliest symptom. Initially pain occurs on sudden movement of spine.
2. Stiffness of back : Is also an early symptom and occur along with pain.
3. Visible deformity : Gibbus or Kyphosis
4. Localized swelling : Due to cold abscess
5. Paraplagia : In neglected cases
6. Constitutional symptoms : Evening fever, loss of appetite, night sweat, loss of weight.

• On examination, following findings may be seen : –

1. Decreased range of motion.
2. Local tenderness : Over the spinous process of affected vertebra.
3. Deformity : –

• Cervical spine : – Straight neck with loss of cervical lordosis.
• Thoracic : – Gibbus/kyphosis
• Lumbar : – Loss of lumbar lordosis
• Para-vertebral swelling : – Cold abscess

Ans. is ‘c’ i.e., MRI

Ans. is ‘a’ i.e., Spine