Bone TB

What is Bone Tuberculosis?

When tuberculosis involves the skeleton, the following joints are affected-(in the order of frequency as shown below)-

Spine

Hips

Knees

Feet

Elbows

Wrists

Shoulders

Sometimes other joints also

Spinal TB is the most known and common form of bone TB.
It is also known as TB Spondylitis or Pott ‘s disease.

What are the causes of Bone Tuberculosis?

Bacilli reach the joints from some focus elsewhere, from lesions in lungs, travel by blood stream

Spread from infected lymph nodes.

From other visceral organs

What is Synovial joint TB?

The disease starts in synovium,grows slowly over cartilage.

Then extends via the cartilage into underlying bone, which then decalcifies.

Symptoms of Bone TB?

Spinal tuberculosis (Pott’s disease) usually affects the thoracic part of the spine.
- Causes constant back pain as the virus degrades the discs cushioning the vertebrae.
- In spine, disease starts in the disc-
- If treated before cartilage destroyed, joint recovers fully.
- Treated late stops disease but joint develops ankylosis.
- Sometimes-abscesses and sinuses lead to secondarily infection.

Patient is usually a young adult or a child above 6 years.

(Although even a year old child & older people can get infected

Progressively painful one or more joints.

Stiffness in joints during previous weeks.

If leg is involved, limping is the first complaint.

A constant pain in the bone can cause complications carpal tunnel syndrome (wrist).

The infected joint gets filled with fluid, and there is wasting of muscles round it.

There is mild to moderate pain, but more on forced movement.

Skin over infected joint is same temperature as normal skin.(‘cold’)

In septic arthritis it is ”hot’, temperature is more than surrounding skin.

Sometimes there can be mild fever, night sweats, or loss of weight or appetite.

Pain and fever may be quite marked.

He may also have signs of tuberculosis in his chest, or a family history of it.

The affected bone may also be weakened and may fracture easily

Treatment of Bone TB

CHEMOTHERAPY

Ideally a 4-drug regimen is advised which can be adjusted as per susceptibility reports.
Isoniazid and Rifampin to be given during the whole course of therapy.
Additional drugs administered during first 2 months of therapy –chosen from streptomycin, pyrazinamide and ethambutol.
A 3-drug regimen usually includes isoniazid, rifampin, and pyrazinamide.
When there is drug resistance, then second-line medications used.

Duration of Treatment-

Somewhat controversial.
Most favour a 6-9 months course.
Traditional courses are from 9 months to one year or even longer.
Usually individualized, based on resolution of symptoms and clinical status.
Resting the joint by sling or otherwise
To admit if required.
Application of traction
Major surgical operations to drain or remove lesion.

The prognosis of Bone TB-
Tuberculous joints can be successfully and cheaply treated if diagnosed early enough, within first few weeks.

How to confirm diagnosis?

Be suspicious as there are no certain diagnostic signs.
- Seeing any chronic bone or joint disease, ask: ”If this Might be tuberculous?” If so, it can be treated

Biopsying a node or synovium confirms diagnosis in 50% cases.
- When joint swollen aspirate and examine fluid.
- When lymph nodes enlarged, get biopsy done.
- Biopsy from spine is difficult, take same from hip joint.
- Biopsies are fallible-accept them with caution.

In Tubercular arthritis, the X-rays show –
- Generalized rarefaction
- Lack of sharpness of joint
- Some Localized areas of erosion or decreased density/erosion.
- Joint space abnormally narrow or wide or irregular.

(CAUTION! Joint destruction in TB always more severe than seen in X-ray.)

Get X-ray of lungs to know extent of infection

Get X-ray of lungs to know extent of infection

CT scan gives very favourable clarity on the quality of bone/joint destruction

Many diagnostic specialists make use of MRI scan for sharp assessment.

Differential Diagnosis of Bone TB

to distinguish from Septic arthritis

Septic Arthritis	Quality	Bone TB
History of Hours and days	ONSET	History of Weeks
Acutely painful in any direction	PAIN	Progressively painful
‘hot joint’	TEMPERATURE OF JOINT	‘cold’ joint
High fever and leucocytosis	FEVER	Mild fever
Severely affected	MOVEMENT	Limitedly affected
High fever and leucocytosis	FEVER	Mild fever
Severely affected	MOVEMENT	Limitedly affected

History of Trauma/injury.
Haemarthrosis
Other forms of arthritis with history of infections like gonorrhoea/dysentery
Rheumatoid arthritis
If child and hip involved- could be – Perthes’ disease/ slipped epiphysis

If old, with history of previous injury, consider osteoarthritis.

History of Trauma/injury.
Haemarthrosis
Other forms of arthritis with history of infections like gonorrhoea/dysentery
Rheumatoid arthritis
If child and hip involved- could be – Perthes’ disease/ slipped epiphysis
If old, with history of previous injury, consider osteoarthritis.

Bone TB

Bone TB

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