Presenter: Dr. Harshavardhan U. Chandane

Guide: Dr. J.B.Panse

Tuberculosis of Spine

Tuberculosis of the spine is one of the oldest demonstrated diseases of humankind.

Evidences of spinal tuberculosis have been found in Egyptian mummies dating back to 3,400 BC.

The descriptions in the Rigveda, Atharvaveda, and Charak Samhita are the oldest known texts in the world literature relating to this disease.

Hippocrates described the clinical condition of spinal infection believed to be tuberculosis.

Epidemiology

1779, Percival Pott gave the first complete report of tuberculosis infection of the spine.

Skeletal tuberculosis accounts for 2- 20% of all extrapulmonary cases in various studies

Vertebral TB constitutes 50% of skeletal TB. 30 million people infected and 2.5 million death

annually. Infects a third of population worldwide. 88% chronic infections of spine accounts for tubercular

infection. Incidence in Indian sub continental origin > whites.

Since the advent of ATT and improved public health measures, spinal tuberculosis has become rare in industrialised countries; although it is still a significant cause of disease in developing countries.

Tuberculous involvement of the spine has the potential for serious morbidity, including permanent neurologic deficits and severe deformity.

Medical treatment alone, or combined medical and surgical strategies, can control the disease in most patients.

Spinal tuberculosis is predominantly a disease of the young, the usual age of presentation being the first three decades of life, while reports from developed countries indicate a much older patient population.

Incidence of skipped lesions is around 7% and incidence of involvement of other bones and joints is around 12%.

The prevalence of spinal tuberculosis is likely to rise as the numbers of those infected with HIV rises in the population.

Children>young adult, but no age bar. Male=Female.Primary infection < 1 yrs.Family history of tuberculosis.Close contact with smear positive.Chest x-ray – evidence of healed TB.Immuno -compromised - HIV ,steroid, DM, CRF,

Malnutrition.Malignancy-lymphoma, leukemia.

Risk factors

Paradiscal/metaphyseal type: Commonest, paradiscal margin of vertebra, spreads through arteries.

Central type: Body of vertebra , spreads along with batson’s plexus of veins – is diffuse osteomyelitis.

Anterior type: results from the extension of the abscess beneath the anterior longitudinal ligament and periosteum.

Posterior type: Rare, involvement of vertebral arch. Sometimes pure tuberculous arthritis of occipito-

atlanto-axial joints can occur.

Mode of spread of Infection :

Pathological Types : • Caseous exudative- increase destruction and

exudation and abscess formation, symptoms & signs of TB more marked.

• Granular- less destructive, rare abscess formation.

Two distinct patterns are identified, the classic SPONDYLODISCITIS, and an increasingly common atypical form SPONDYLITIS without disc involvement.

The basic lesion is a combination of osteomyelitis and arthritis.

Initial insult is of tuberculous endartertitis leading to necrosis and granuloma formation (hallmark)

This increases in size and results in destruction of lamellar structure of verterbral body.

Increased fragility leads to deformities, compression, collapse.

Common during 1st three decades. Occurrence: Thoracic(42%) >

lumbar(26)>thoraco-lumbar(12%)>cervical(12%)>cervico-thoracic(5%)sacrum(3%).

Presentation depends upon the stage of the disease, site of the disease, and presence of complications such as neurologic deficit, abscesses, or sinus tracts.

Presentation

Active stage:Localized painful movement (tender on palpation) or

referred pain depending upon the nerve root involvement.

Cold abscess.Constitutional symptoms.Evidences of associated extra-skeletal tuberculosis

like cough, expectoration, lymphadenopathy, diarrhoea, and abdominal distension.

95% cases commonly have kyphotic deformity.

• Back pain (spinal or radicular) is the earliest and most common symptom .This pain may worsen with activity.

• Relaxation of muscles during sleep permits movements which are very painful and wake-up the patient (night cries).

• As the infection progresses, pain increases, and paraspinal muscle spasm occurs.

• Muscle spasm obliterates the normal spinal curves, and all spinal movements become restricted and painful.

• Neurological deficits may occur early or late. Early- epidural extension of an abscess. Late- significant kyphosis, vertebral collapse with retropulsion of bone and debris, or late abscess formation.

• Neurological symptoms become more frequent at higher spinal levels.

• Clumsiness in walking, and spontaneous twitching of muscles are early signs of neurological involvement which can progress to a single nerve palsy, to hemiplegia, or paraplegia with spasticity, sensory impairment, bladder/bowel involvement.

• Paraplegia is very rarely a presenting manifestation.

Healed Stage:• All signs and symptoms subsides except the

deformity that occurs in active stage persists.• Radiologically signs of bone healing.• However patient rarely presents with neurological

deficits initially.

Cold abscess is formed by collection of liquefied products and reactive exudates, consists of serum, leucocytes, caseous material, bone debris and tubercle bacilli.

Present far away from vertebral column along fascial plane or course of neurovascular bundles.

Anterior and posterior cervical triangles, paraspinal region at back, along brachial plexus in axilla, intercostal space in chest wall, dorsolumbar abscess along psoas sheath to be palpable in iliac fossa, in upper part of thigh or even downward up to knee.

Cold abscess

Anemia, lymphocytosis, raised ESR. Mantoux Test may be positive but not diagnostic. It demonstrates a positive finding in 84 - 95% of

patients who are non-HIV-positive 1 to 3 months after infection.

Coexistent infection by HIV and other immune deficiency conditions can give a false negative skin test.

ELISA for antibody to mycobacterial antigen-6 showed sensitivity of 94% and specificity 100% (stroebel et al. 1982).

Chest X-ray and sputum for AFB Stain & c/s. PCR -100% specificity, is not readily available.

APPROACH TO DIAGNOSIS

Important diagnostic test, first line of imaging.

Early-

narrow disc space,

osteopenia ,

indistinct paradiscal margin.

Late-

ant. wedge compression,

concertina collapse ,

destruction of post. element.Knuckle, angular kyphosis, round kyphosis.

X ray imaging

Paravertebral abscess- In thoracic spine - fusiform or globular

radiodense shadow called the bird nest appearance.

Tracheal shadow > 8 mm and/or change in normalcontour in C7 to T4 area.

Long standing abscesses may produce concave erosions around the anterior margins of the vertebral bodies producing scalloped appearance called aneurysmal phenomenon.

Difficult in diagnosing early lesion. Lesion less than 1.5 cm not demonstrable in conventional x ray. Must have 30-40% of calcium removed from particular area to show radiolucent region on x-ray.

Average vertebra involved at diagnosis – 3(in children) and 2.5 (adult).

7% may show skipped lesions in vertebral column.

Radiological sites of Tuberculosis involvement:

Paradiscal, Central, Anterior, Appendicial.

• Paradiscal commonest variety. narrowing of disc space at earliest findings. Any reduction in disc space associated with a loss of

definition of paradiscal margin must invite suspicion.• Central Infection starts from the centre of vertebral body. Diseased vertebra ballooned out like a tumor. Later stage-vertebra shows concentric collapse

resembling vertebral plana. Minimal diminution of disc space and Paravertebral

shadow .

• Anterior Type Lesion starts beneath anterior longitudinal ligament and

periosteum. Peripheral portion of vertebral body in front and side

shows erosions Collapse of vertebral body and diminution of disc space

is minimal and occurs late. More common in thoracic region and children. Appendicial Uncommon type Isolated infection of lamina, spine, pedicle, transverse

process. Shows erosive lesion, paravertebral shadow and intact

disc space. 30% of typical paradiscal type show concomitant

involvement of posterior element.

Ultra sonography : diagnose the presence of TB abscess in lumbar region

and abscess composition and quantity.

CT scanning For a radiolucent lesion to be seen on a plain radiograph, 30% of

mineral loss must be there. CT and MRI detect lesions at an earlier stage.

CT scanning provides much better bony detail of irregular lytic lesions, sclerosis, disc collapse, and disruption of bone circumference.

Specially helpful in detecting posterior spinal disease, craniovertebral and cervicodorsal region , SI joints and of sacrum.

More effective for defining the shape and calcification of soft tissue abscesses.

Useful in assessing bone destruction, but is less accurate in defining the epidural extension of the disease, and therefore, its effect on neural structures.

MRIGold standard for evaluating disc space infection and

osteomyelitis of the spine. It effective for demonstrating the extension of disease

into soft tissues and the spread of tuberculous debris under the anterior and posterior longitudinal ligaments.

MRI is most effective for demonstrating neural compression.

MRI with contrast is helpful in differentiating from non-infectious causes and delineating the extent of disease.

Serial MRI can be used to assess the response to treatment and regression of the disease.

Bone scanBone scan with Tc-99m is considered to be highly

sensitive, but nonspecific. It may only aid to localise the site of active disease and to detect multilevel involvement.

Patients with active disease have an increased uptake, whereas in avascular segments and abscesses it may show decreased uptake

Even lesions of 5 mm size can be localized as hot spot.

Histopathology and microbiology Because of high prevalence, microbiological diagnosis

is not mandatory to start chemotherapy in our country. However, a biopsy/aspiration may be needed in cases

of doubtful clinic radiological findings, lack of proper response to drug therapy, and suspicion of drug-resistant strains.

Biopsy study findings may be positive in only about 50% of the cases.

CT-guided needle biopsy and/ or aspiration is widely done.

Percutaneous needle aspiration and/or biopsy is a newer method with comparable yields as for surgical biopsy.

Definitive diagnosis is dependent on culture of the organism and requires biopsy of the lesion.

Clinicoradiological classification of typical tubercular spondylitis

Stage Clinico-radiological features Usual duration

I) pre-destructive Straightening of curvatures, spasm of perivertebral muscles, bone scan would show hyperemia, MRI shows marrow edema

< 3 mths

II) Early-destructive

Diminished disc space with paradiscal erosions (knuckle) MRI: marrow edema and break of osseous margins, CT scan: marginal erosions or cavitations

2 – 4mths

Stage III, IV ,V have vertebral bodies destruction

and collapse and appreciable kyphos

III)Mild angular kyphos

2-3 vertebrae involved (K: 10 to 300 ) 3 – 9 mths

IV)Moderate angular kyphos

>3vertebrae involved (K: 30 to 600 ) 6 – 24 mths

V) Severe kyphos ( humpback)

>3vertebrae involved (K: > 600 ) > 2 yrs

Measurement of k angle

Forward wedge of 2 vertebral bodies- knuckle.Wedge collapse of 3 or more vertebra- angular. Wedging of large no of adjacent vertebra- round

kyphosis.

Tall vertebra-occurs only during growth period increase in height of lumbar vertebral bodies

( up to 1\3 rd) in healed thoracic pott’s disease.

Angulation of spine: posterior convexity

Age: confused with Young child calve”s disease, congenital defect and adults with Scheuermann”s disease.

PYOGENIC SPONDYLITIS: sudden onset, severe localized pain, spasm, fever. initially rapid bone destruction which is replaced

rapidly by bone sclerosis and new bone formation (Radiologically after 8th wks)

usually follows recent surgery or infection examination of biopsy useful MRI shows inflammatory changes heals with marked sclerosis, proliferative bone

formation, even with ankylosis.

Differential Diagnosis

Benign

Hemangioma- most common (10.7%) . Asymptomatic usually and found incidentally , D12 to L4 most commonly involved. Involved vertebra radiologically shows characteristic coarsening of vertebral trabaculations more prominent in vertical than horizontal.

GCT and ABC- typical osteoytic, expansile and usually eccentric growth on radiological examination. disc space is not involved in early stage. Final diagnosis made histologically.

Malignant

Primary malignant are rare ,but Ewing's and Osteogenic sarcoma occasionally occur. Tumors have rapid course of disease with progressive paraplegia and radiological evidence of bony trabecular destruction. Diagnosis confirmed by biopsy.

Tumour like conditions

Multiple myeloma

may resemble Pott’s TB with involvement of only 1 or 2 vertebra and if there is collapse and eccentric destruction. Involvement of multiple joints ,high ESR, anemia , Bence Jones protein, reversal of albumin globulin ratio, electrophoresis helpful in diagnosis. Confirmed by biopsy shows myeloma cells.

Lymphomas-(Hodgkin’s disease, Leukaemias)

may rarely involve spine, diffuse sclerosis of bone and trabecular destruction. Enlargement of spleen , liver, and lymph node with characteristic haematological changes.

Secondary neoplastic deposits -largest percentage of neoplasm of spine. onset more acute, progress more rapidly and local sign more widespread. Secondary deposit nearly always involve vertebral body with no disc involvement.

Traumatic condition-usually traumatic fracture is wedge shaped with intact disc space. There may be marginal spurring and spondylitis changes.

Eosinophilic granuloma- self limiting. Develop in vertebral body which undergoes an extensive degree of concentric collapse. The disc above and below are not involved . Usually disease occur between 6 and 12 years of age and patient complains of localized pain without constitutional symptom.

Osteoporosis- may lead to collapse of vertebral column. In pre-collapse stage vertical bony trabeculae are more prominent but there is no evidence of osteolytic destruction. Nucleus pulposus of disc expands and attain a biconvex appearance and biconcave vertebral bodies.

Mycotic spondylitis-. In blastomycosis, paravetebral abscess formation and in actinomycosis sclerosis and destruction of bone occur. Anterior and lateral surface of several vertebral body may be involved and may show an irregular saw tooth appearance by periosteal new bone formation.

Syphilis- Rare. Thoraco-lumbar and lumbar spine are common

Three types-arthralgic type, gummatous type and charcots diseases.

. Radiological- gross disorganization and destruction of involved vertebra along with proliferative new bone formation.

Serological test, biopsy.Local developmental abnormalities.

Due to Tubercular Infection Potts Paraplegia Cold Abscess Sinuses Fatality Secondary infection Amyloid Disease.

Complications

Neurological complications

Most dreaded and crippling complications. Overall incidence 10 to 30 %. More common in first 3 decades of life.Tuberculous pathology remains commonest

pathology for paraplegia in developing countries.

Classification of tuberculous paraplegia/tetraplegia(predominantly based on motor weakness)

I : negligible – pt unaware of neural deficit , physician detects plantar extensor and /or ankle clonus.

II : mild- pat aware of deficit but manages to walk with support. All signs of spastic paresis present.

III : moderate- non ambulatory because of paralysis in extension, sensory deficit less than 50%.

IV : severe – stage III + flexor spasms/paralysis in flexion/ flaccid / sensory deficit more than 50%/ sphincters involved.

HIGHER THE STAGE OF PARALYSIS , MORE SEVERE IS THE CORD COMPESSION AND POORER IS THE PROGNOSIS.

Pathology of tuberculous paraplegiaInflammatory edema – cause of early cases of neuro

deficitsExtradural mass – commonest mechanismBony disorders- sequstra, angulation of the diseased

spine, pathological dislocation leading to mechanical instability

Meningeal changes- peridural fibrosisInfraction of spinal cord- rare but important cause

since paralysis caused is irreparable.

MyelographyIndications- paraplegia without evidence

radiologically, as in cases of “spinal tumor syndrome”, or when multiple vertebrae are involved.

Also when there is no recovery after surgical decompression to demonstrate inadequate decompression.

Medical treatment Medical treatment is in the form of ATT. There is a lot of discordance among experts on the

duration of anti tuberculous treatment.British Medical Research Council and US Centres

for Disease Control and Prevention indicate that tuberculous spondylitis of the thoraco-lumbar spine should be treated with combination chemotherapy for 6 - 9 months.

However, British Medical Research Council studies did not include patients with multiple vertebral involvement (which is commoner in our country), cervical lesions, or major neurologic involvement.

WHO/RNTCP guidelines consider spinal tuberculosis with neurological deficit to be severe extra pulmonary (category 1 ) and should receive treatment for 6 months.

In relapse or treatment failure, it should be given treatment according to category 2, i.e., for 9 months

The currently recommended regime is four-drug therapy include isoniazid, rifampicin, pyrazinamide, ethambutol . In children, ethambutol is replaced by streptomycin.

In view of multiple vertebrae involvement, extensive disease, neurological involvement; most of the authorities in India prefer to give ATT for 18 months – HRZE 4 + HR14 .

Treatment protocol of HIV positive patients is same as of HIV negative. Patients with lower CD4 counts have poor prognosis

Surgical treatment Opinion varies regarding the operative

indication for Pott’s spine. A large group of surgeons perform

debridement and decompression in all cases, irrespective of neurological involvement.

Others perform operative decompression only in those patients who do not respond to chemotherapy.

Resources and experience are key factors in the decision to use a surgical approach.

• Indications for surgery are neurologic deficit, spinal deformity with instability, severe or progressive kyphosis, retropulsed bone fragments in the canal, large abscess causing respiratory embarrassment, and no response to medical therapy.

• Post-operatively the patient is advised absolute bed rest for three months, and then gradually mobilised in a spinal brace.

• A lower threshold for surgery is recommended in case of cervical spine involvement as it is more commonly associated with higher incidence and severity of neurological deficits and abscess compression.

treated on non operative basis, anti TB chemotherapy, rest and spinal braces.

Hospitalization for those who require surgical evacuation of abscess or debridement of vertebral lesions or those who agree for fusion of spine for extensive dorsal lesion in children or for an unstable and painful spinal lesion or paraplegics who are unable to walk.

PROTOCOLS:

I ) Rest: in hard bed or plaster of Paris bed to put the disease part in rest.

Middle path regime of SM Tuli

II ) Anti-tubercular Drugs: intensive phase of 5 to 6 m: H-300 to 400 mg , R –

450 to 600 mg and ofloxacin – 400 to 600 mg continuation phase of 7 to 8 m : H and Z 1500 mg,

for 3 to 4 m followed by H and E 1200 mg for 4 to 5 m prophylactic phase – for 4 to 5 m: Z and E Pyridoxine 10mg prevent peripheral neuropathy due

to INH. Supportive therapy with haematinics, analgesics,

multivitamins and high protein diet.

90% Bony healing, 10% Fibro-osseous.early stage of healing shows disease foci surrounded

by sclerotic bones (ivory vertebra).early radiological signs of healing: sharpening of the

fuzzy paradiscal margins, & reappearance and mineralization of bone which had earlier been absorbed.

III ) Radiographs and ESR are taken at 3 to 6 months interval for 2 years.

IV ) Gradual mobilization

is encouraged in the absence of neural deficit with help of suitable spinal braces after the comfort at the diseased site permits. At 8 to 9 weeks of treatment back extension exercise. Spinal brace continued for 18 months to 2 years.

V ) Sinuses

usually heals within 2 to 3 months. Few may require excision of tract.

VI ) Abscesses

are aspirated when its near the surface and one gram of streptomycin with or without INH instilled at each aspiration. Sufficient to heal about 95%. 5% requires surgery

Open drainage or suction drainage for 72 hours of abscess is performed if aspiration fails to clear.

Clinical factors influencing prognosis of cord involvement

Cord involvement Better prognosis Relatively poor prognosis

Degree Partial – stage 1 and 2 Complete – stage 3 and 4

Duration Shorter Longer > 12 months

Type Early onset Late onset

Speed of onset Slow Rapid

Age Younger Older

GC Good poor

Vertebral disease Active Healed

Kyphotic deformity < 600 > 600

Cord on MRI Normal Myelomalacia / syrinx

Per operative Wet lesion Dry lesion

VII ) Neural complication- If the patient shows progressive neurological recovery

with in 3 to 4 wks surgical debridement is not necessary.

Indication of surgical decompression If progressive recovery to satisfactory level after of fair

trial of conservative therapy do not start. Neurological complication develops during the

conservative treatment. Neurological complication become worse or there is

recurrence. Para vertebral cervical abscess with difficulty in

deglutition or respiration. Advance case with Motor, Sensory and Sphincter

involvement. Doubtful diagnosis

VIII) Operative debridement advised for cases who don’t show arrest of the activity of the spinal lesion after 3 to 6 months of chemotherapy or the cases with recurrence. Posterior spinal arthrodesis recommended for unstable spinal lesions in which the disease otherwise seems to be arrested.

IX ) Post-operative- Patient are nursed on hard bed for 2 to 3 weeks, in case of neural complications 3 to 5 months, the patient is gradually mobilized with the help of spinal braces.

C1-C2:Anterior, Transoral/ TransthyroidCervical Region: Anterior, Through Anterior/ Posterior triangle.C7-D1:Transpleural (3rd rib), Anterior Cervical, Low Ant. Cervical.Dorsal: Anterolateral or Transpleural, Ant. Transpleural D5-

D12, Trans-sternal D3-D4.Dorso-lumbar: Anterolateral ,11th rib Extra pleural/ Extra

peritoneal or 9th rib Left Transpleural.Lumbar: Retroperitoneal, or Ureter or Sympathectomy

Approach, Antero-lateral, Renal ApproachL5-S1:Transperitoneal in Trendelenburg position with

paramedian or low midline Incision, Retroperitoneal through oblique renal or hemisection incision, Retropsoas transverse vertebrotomy.

Surgical Approaches: Described by Various Authors

Decompression ± fusion for neurological complications which failed to respond to conservative treatment or are very advanced.

Decompression ± fusion in failure of response in 3 to 6 months of non-operative treatment.

Doubtful diagnosis.Fusion of symptomatic mechanical instability after

healing.Debridement ± Decompression ± fusion in

recurrence of disease or of neural complications.

Main indications for various operations for vertebral tuberculosis

Prevention of severe kyphosis by debridement + fusion by panvertebral operation in children with extensive dorsal lesions.

Anterior transposition of cord through extrapleural anterolateral approach for neural complications due to severe kyphosis.

Laminectomy has no role, except for extradural granuloma/tuberculoma presenting as spinal tumor syndrome, or a case of healed disease presenting with secondary canal stenosis.

• Due to efficacy of modern ATT absolute indications for surgery are reduced to nearly 5% of uncomplicated cases and to about 60% of cases with neurological complications.

• All pts who recover are able to return to full activity within 6 to 12 months of treatment.

• Active life is permitted with suitable braces which are gradually discarded within about 2 years.

Poor prognostic factors include neurological deficit of more than one year duration, myelopathic changes in the cord, and increased pre-treatment kyphotic angle, poor compliance, drug resistance.

Newer techniques such as sensory and motor evoked potentials are being studied as a prognostic marker of outcomes of Pott’s paraplegia.

Current treatment modalities are highly effective and if not complicated by severe deformity or established neurologic deficit results, are usually good.

Prognosis