Ankylosing Spondylitis

Ankylosing Spondylitis

1. Definition
   Ankylosing spondylitis (AS) is a chronic inflammatory arthritis that mainly involves the spine and sacro‑iliac joints, leading eventually to fusion of the vertebrae and loss of spinal mobility.

2. Causes / Etiology
   The exact cause is unknown. A strong genetic predisposition is seen with the HLA‑B27 antigen. Environmental factors such as infections may trigger the disease in genetically susceptible individuals.

3. Types or Classification

• Classical AS – inflammation of sacro‑iliac joints and spine with typical radiographic changes.
• Peripheral AS – predominant involvement of peripheral joints (knees, hips) with or without spinal disease.
• Undifferentiated spondyloarthritis – does not fulfil full criteria for AS but shows similar features of enthesitis and axial pain.

4. Pathology (step‑wise)
   step 1 → Inflammation begins at the entheses (sites where tendons/ligaments attach to bone).
   step 2 → Inflammatory cells release cytokines (TNF‑α, IL‑17) that activate osteoclasts (bone‑resorbing cells).
   step 3 → Bone resorption is followed by activation of osteoblasts (bone‑forming cells) producing new bone at the inflamed sites.
   step 4 → Repeated cycles cause fibrosis and eventual ankylosis (fusion) of the vertebrae, giving the characteristic “bamboo spine”.

5. Clinical Features
   General – persistent low‑back pain, early morning stiffness lasting > 30 min, improvement with exercise, fatigue, reduced chest expansion.
   Specific – pain over sacro‑iliac region, peripheral joint swelling (especially hips and knees), enthesitis (heel pain), anterior uveitis (red eye), possible inflammatory bowel symptoms.

6. Complications
   Acute – vertebral fractures due to osteoporosis, spinal cord or nerve root compression, acute anterior uveitis.
   Chronic – severe spinal rigidity, restrictive lung disease from limited chest expansion, osteoporosis with risk of fractures, cardiovascular involvement (aortitis).

7. Diagnosis / Investigations
   Routine – ESR and CRP usually raised; plain X‑ray of sacro‑iliac joints and spine shows sacroiliitis and “bamboo spine”.
   Special – MRI of sacro‑iliac joints and spine detects early inflammatory changes before X‑ray; HLA‑B27 typing supports diagnosis; bone scan may show increased uptake at entheses.

8. Management
   General – regular supervised exercise, physiotherapy focusing on posture and chest expansion, smoking cessation.
   Modern treatment – NSAIDs as first line for pain and stiffness; if inadequate, disease‑modifying agents such as sulfasalazine for peripheral disease and biologics (TNF‑α inhibitors, IL‑17 inhibitors) for axial disease.
   Dietary advice – balanced diet rich in calcium and vitamin D, maintain healthy weight, avoid excessive alcohol, include omega‑3 fatty acids (fish oil) for anti‑inflammatory effect.

9. Homeopathic Therapeutics (keynotes)

Rhus toxicodendron

• Pain and stiffness in the back that improve with movement.
• Worse in cold, damp weather.
• Burning sensation over sacro‑iliac region.
• Restlessness, desire to keep moving.
• Useful in early stages with marked stiffness.
• Good for patients who feel better after warm applications.

Bryonia

• Severe, stitching pain aggravated by any movement, relieved by rest.
• Pain worsens in cold, dry weather.
• Tendency to hold the body in a rigid, curled position.
• Thirst for large quantities of cold water.
• Beneficial when stiffness lasts for hours after waking.

Kali mur (Kali muriaticum)

• Progressive rigidity of the spine with a feeling of “hardening”.
• Pain in the lower back radiating to the thighs.
• Marked loss of chest expansion.
• Tendency to develop osteoporosis.
• Helpful in chronic, fibrotic stages.

Causticum

• Stiffness of the neck and back with a sensation of “tight band”.
• Weakness of the muscles, especially in the upper limbs.
• Difficulty in breathing due to restricted chest wall.
• Better on warm applications, worse in cold.

Natrum muriaticum

• Chronic low‑back pain with emotional stress component.
• Tendency to be introverted, prone to grief.
• Pain improves with warmth and fresh air.
• Useful when there is a family history of similar rheumatic disease.