A Glimpse on Osteo-articular Tuberculosis

Dr Khushwant Singh Rathore Senior Resident AIIMS, Jodhpur

The tubercle bacillus has co-existed with Homo sapiens since time immemorial.

The Vedas and Samhita of Charaka & Sushruta recognized the disease as “Yakshma” Tuberculous lesions have been found even in Egyptian mummies.

Prevalence

The prevalence of the disease is around 30 million globally and approximately 30% or 10 million cases exist in India, 21-3% of the 10 million have involvement of bones & joints.

The predisposing factors 1). Malnutrition 2). Environmental conditions and living standards such as poor sanitation, over crowded housing and slum dwelling. 3). A diabetic status is an important pre-disposing factor. 4). Acquired immune-deficiency syndrome has certainly led to a resurgence of tuberculosis.

Osteo-articular disease is always secondary to a primary lesion in the lung or other viscera.

Aetio-pathogenesis Osteo-articular tuberculosis occurs in the following order:-

Spine>hip>knee>foot>elbow>wrist>hand>shoulder>bursal sheaths>others.

The major method of spread is haematogenous.

The most common method of spread to the vertebral body is through Batson's pre-vertebral venous plexus.

Primary focus in viscera

Haematogenous seeding in skeletal tissue

Ingested by mononuclear cells

Coalesce to form epitheloid cells

Lymphocytes form a ring around epitheloid cells to form a tubercle.

casseation in centre of tubercle

Abscess tracks along paths of least resistance to present over skin as swelling which may rupture to form sinus

Disease Presentations

Spine – Pott’s disease & Pott’s paraplegia

Joints - Tubercular arthritis

Long and flat bones - Tubercular osteomyelitis

Short bones – Tubercular dactylitis(spina ventosa)

Tendon sheath & bursae- TB bursitis & tenosynovitis

Tuberculosis of the Spine

Most frequent site of osseous involvement by TB

the disease was first described by Sir Percival Pott in 1779, hence the name Pott's disease

There has been a resurgence of the disease in the developed countries following the HIV pandemic.

Defined - as an infection by Mycobacterium tuberculosis of one or more of the extradural components of the spine namely the vertebra, intervertebral disks, paraspinal soft tissues and epidural space

Introduction

Usually by hematogenous route

Peri-vertebral arterial or venous plexus is still in debate, but arterial route considered more important.

Primary focus in the lung or other extra-osseous foci such as lymph nodes, GIT or any other viscera

Lower thoracic and lumbar vertebrae are most often affected Usually two continuous vertebrae are involved but several

vertebrae may be affected, skip lesions and solitary vertebral involvement may occur

The so-called skip lesions or a second lesion not contiguous with the more obvious lesion is seen in 4 -10 % of cases.

Pathophysiology

CLINICAL FEATURES

PRESENTATION VARIES FROM NON SPECIFIC BACK ACHE TO CATASTROPHIC PARAPLEGIA

COMPLAINTS: PAIN

STIFFNESSCOLD ABSCESS ( IF EVIDENT EXTERNALLY)PARAPLEGIADEFORMITYCONSTITUTIONAL SYMPTOMS (20-30% patients only)

EXAMINATION

SHOULD HAVE A HIGH INDEX OF SUSPICION AIMS : LOOK FOR FINDINGS OF TB SPINE

LOCALISE SITE OF LESION DETECT COMPLICATIONS- COLD ABSCESS /

PARAPLEGIA GAIT : SHORT STEPS ATTITUDE & DEFORMITY PARAVERTEBRAL SWELLING TENDERNESS ON THE AFFECTED SPINE REDUCED MOBILITY

DEFORMITY : GIBBUS

NEUROLOGICAL EXAMINATION

AIMS: DETECT ANY COMPRESSIONLEVEL OF COMPRESSIONSEVERITY OF COMPRESSION

LIMBS – UPPER OR LOWER BASED ON SITE MOTOR , SENSORY , REFLEXES , BOWEL AND BLADDER

FUNCTIONS

GENERAL EXAMINATION PHYSICAL EXAMINATION SYSTEMIC ILLNESS : DM , HYPERTENSION

GENERAL INVESTIGATIONS

ESR MANTOUX ELISA : ANTI TB ANTIBODY CHEST X RAY : FOR PULMONARY TB

Conventional Radiographs – Initial investigation

often negative in early disease

More than 30 to 50 % of mineral must be lost before a radiolucent lesion becomes conspicuous on the plain films and this takes about 2 to 5 months

Imaging modalities

Abscess formation – Paravertebral soft tissue opacity Usually out of proportion to the degree of osseous

destruction commonly bilateral and uniform may be globular indicating pus under tension may be minimal in the central variety of tubercular lesion

cervical region - widening of the pre-vertebral soft tissues dorsal spine - the posteromedial pleural line is displaced

laterally & the abscess produces as typical fusiform shape called the "birds nest" appearance

RETROPHARYNGEAL ABSCESS MEDISTINAL WIDENING

Birds nest abscess Psoas Abscess

Advantages – early detection of bone and soft tissue changes when plain films

are normal better anatomic localization and characterization of lesions evaluation of areas difficult to evaluate on plain films such as

cranio-vertebral junction, cervico-dorsal junction, sacrum providing guidance for biopsy and surgical approach

Computed Tomography

modality of choice advantages –

multiplanar capability the direct demonstration of early bone marrow involvement or

edema unsurpassable assessment of spinal canal and neural

involvement Soft tissue and Intraosseous abscesses are also well

demonstrated on MR imaging

Higher sensitivity for early infiltrative disease including endplate changes and marrow infiltration than bone scan and plain films

Magnetic Resonance Imaging

MRI Scores over CT in-

Detection of early disease (marrow edema) Skip lesions more easily and more often detected. Incidence of

multilevel noncontiguous vertebral tuberculosis is generally reported to be between 1.1 and 16 %

Detection of epidural, meningeal and cord involvement Planning the surgical approach

• COMPLICATIONS

COLD ABSCESSNEUROLOGICAL COMPLICATIONS : PARAPLEGIA

Types of paraplegia

EARLY ONSET – during active phase, < 2 years INFLAMMATORY EDEMA EXTRADURAL PUS & GRANULATION TISSUE – COMMOMN SEQUESTRA INFARCTION OF SPINAL CORD EXTRADURAL GRANULOMA

LATE ONSET – during healed phase, > 2 years internal gibbus recurrence

TREATMENTWhat is Middle path regime?(why called middle path)

Rest in bed

Chemotherapy (ATT 4HRZE + 8 HRE)(ATT?)

X-ray & ESR once in 3 months

MRI/ CT at 6 months interval for 2 years

Gradual mobilization is encouraged in absence of neural deficits with spinal braces & back extension exercises at 3 – 9 weeks.

Abscesses – aspirate when near surface & instil 1gm Streptomycin +/- INH in solution

RX of COLD ABSCESS

SMALLER ONES SUBSIDE WITH TB THERAPY

IN SUPERFICIAL ABSCESSES : ASPIRATION : USING THICK NEEDLE EVACUATION PSOAS ABSCESS : drain retroperitoneally

Rx of paraplegia CONSERVATIVE : ANTI TB RX , REST TO SPINE , SURGICAL :

INDICATIONS : PARAPLEGIA IN CONSERVATIVE Rx SUDDEN ONSET SEVERE PARAPLEGIA SEVERE PARAPLEGIA : IN FLEXION, MOTOR /

SENSORY LOSS > 6 MONTHS OR COMPLETE MOTOR LOSS ONE MONTH DESPITE CONSERVATIVE Rx

PARAPLEGIA WITH UNCONTROLLED SPASTICITY

PROCEDURES

1. COSTO TRANSVERSECTOMY

2. ANTEROLATERAL DECOMPRESSION

3. RADICAL DEBRIDEMENT AND ARTHRODESIS ( HONKONG OPERATION)

4. LAMINECTOMY

Involvement in about 15 % cases of osteo-articular TB

Lesions can arise in acetabulum, synovium, femoral epiphysis or metaphysis or spread to the hip from foci in the greater trochanter or ischium.

If upper end of femur involved(being entirely intracapsular), the joint is involved early in disease

Erosion or lytic lesions may also occur in the greater trochanter or the overlying bursa, without involvement of the hip joint for a long period of time

Tuberculosis of Hip

Clinical - Irritable hip, FABER with APPARENT LENTHENING

Radiography –

Plain radiograph usually normal

Displacement of fat planes (effusion)

Soft tissue swelling and deossification

Radiologically significant osteoporosis appears 12 to 18 weeks after onset of symptoms

Stage of synovitis

Ultrasound, CT and MRI more sensitive in this stage to detect increased joint space

and accumulation of fluid.

Clinical – FADIR + Stage of apparent shortening Peri-articular erosions Reduction of joint space (destruction of articular

cartilage) Lesions can usually be picked up on CT before they are

apparent on plain radiographs

Stage of early arthritis

Clinical – FADIR + stage of true shortening Destruction of articular cartilage, acetabulum, femoral head,

capsule and ligaments

Capsule may get thickened and contracted

Upper end of femur may displace upwards and dorsally breaking the Shenton’s line

Lower part of acetabulum empty (Wandering acetabulum)

If femoral head, neck are grossly destroyed and collapsed in on enlarged acetabulum, this appearance is called "mortar and pestle" appearance

Stage of advanced arthritis

Stage of advanced arthritis - Complete destruction, deformity & subluxation Wandering acetabulum

Mortar & pestle appearance• Gross destruction of head• Enlarged acetabulum

• Management1. Synovitis + early arthritis

rest+ traction+ ATT

2. advanced arthritis

joint debridement & achieve favourable ankylosis by traction if painful ankylosis

excision arthroplasty arthrodesis corrective osteotomy THR(After 2 years)

THANKS