ANKYLOSING SPONDYLITIS

• Ankylosing spondylitis, a type of seronegative spondyloarthropathy, is a chronic inflammatory disease of the axial skeleton that leads to partial or even complete fusion and rigidity of the spine.
• Males are disproportionately affected and the histocompatibility antigen type HLA B27 is positive in over 90% of patients and 53% of their first degree relatives
• The predominant clinical feature is inflammatory back ache followed by stiffness of spine. The pain typically improves with activity and is especially prominent at night
• Ankylosing spondylitis typically affects the structures of the spine and enthuses. Ascending progression of the disease leads to typical bamboo spine appearance
• Synonyms – Marie-Strumpell disease, Bamboo spine, Poker back

• Ankylosing spondylitis has no known specific cause, though genetic factors seem to be involved
• Genetic predisposition: 90–95% of patients are HLA-B27 positive

Risk factors

• Sex-Men are more likely to develop Ankylosing spondylitis than are women
• Age- Onset generally occurs in late adolescence or early adulthood

Articular symptoms

• AS develops insidiously with chronic low back pain associated with morning stiffness, which is the presenting feature in 85% cases. The back pain is due to sacroilitis and inflammation of the several enthesal sites where the spinal ligaments attach with the vertebral bodies
• The inflammation of sacroiliac joint is felt as deep sacral pain, or buttock pain
• Over the years inflammation progress with involvement of dorsal and cervical spine. With the involvement of dorsal spine patients complain of chest pain and tightness of chest
• Arthritis of the hip and joints and asymmetric arthritis of the peripheral joints occur
• Enthesitis – pain and tenderness of Achilles tendon, plantar fascial insertion sites at the calcaneous bone, costochondral junction, anterior posterior superior iliac spine , iliac crest etc
• Obliterated lumbar lordosis, buttock atrophy and accentuated thoracic kyphosis. A forward stoop of the neck and flexion contractures at the hip, compensated by flexion at the knees occurs
• Severe spinal restriction occurs and majority of the patients are severely restricted within 10 year of onset
• Patient complains of night pain and sleep disturbances

Extra-articular manifestations

• Most common extra articular manifestation is acute, unilateral anterior uveitis (in 25- 40 % of cases) 
• Cauda equine syndrome due to chronic adhesive arachnoiditis
• Aortitis may occur leading to aortic regurgitation
• Fatigue, weakness, fever, weight loss
• Heart block, pericarditis and fibrosis of the upper lobes of the lung
• Restrictive pulmonary disease due to decreased mobility of the spine and thorax
• Gastrointestinal symptoms: associated with chronic inflammatory bowel disease ( 5–10% of cases) 
• Kidney: IgA-nephropathy

Differential diagnosis

• Mechanical low back pain : early morning stiffness and raised ESR or CRP is absent
• Diffuse idiopathic skeletal hyperostosis (DISH): flowing osteophytes bridge adjacent vertebrae
• Fibromyalgia
• Disc prolapse
• Vertebral osteomyelitis
• Other spondylo arthritis (e.g., reactive arthritis, psoriatic arthritis)

Clinical tests

Chest expansion measurement

• measure chest circumference in full expiration and inspiration, Pathological difference < 2 cm is suggestive of AS

Spine mobility tests

Schober’s test

• Two points, one 10 cm above and 5 cm below the lumboscaral junction is marked in upright position and then the patient is asked to fully flex forward and the expansion is noted. It is considered abnormal if the expansion is less than 5 cm

Examination of the hip

Mennell sign

• Tenderness to percussion and pain on displacement of the sacroiliac joints 

FABERtest

• FABER (Flexion, Abduction, and External Rotation) provokes pain in the ipsilateral hip

Laboratory findings

• ↑ CRP and ↑ESR
• Auto-antibodies (e.g. RF, ANA) are negative
• HLA-B27 positive in 90 % of cases 

X-ray

• Pelvis : Bilateral sacroiliitis, including ankylosis (fusion of the articular surfaces) , Pseudo widening and erosion of sacroiliac joints
• Spine : Loss of lordosis with increasing abnormal straightening of the spine , Sclerosis of the vertebral ligamentous apparatus, Syndesmophytes resulting in a so-called 'bamboo spine' , Signs of spondyloarthritis, including ankylosis of intervertebral joints
• Thorax: Ankylosis of costosternal and costovertebral joints 

MRI

• Sacroilitis with high intensity bone marrow oedema

CT

• Sacroilitis , hip arthritis

New York criteria for diagnosis

• Limitation of spine in all plains
• Pain in lumbar spine or dorsolumbar junction
• Chest expansion less than 2.5 cm

• Physical therapy: Consistent and rigorous physical therapy, Back extension excercises, swimming ensures adequate spinal movement
• Medical therapy: NSAIDs (e.g. indomethacin), Tumor necrosis factor-α inhibitors ,glucocorticoids
• Surgery: in severe cases to improve quality of life. Indicated when there is severe deformity of the spinal column, Instability of the spine and Neurologic deficits. Total hip arthroplasty , corrective osteotomy may be of use

Management is aimed at controlling inflammation and increasing mobility

Internal medications

• Amruthothara kashaya
• Dasamoolarasnadi kashaya
• Rasna erandadi kashaya
• Amrutarishta
• Punarnavasava
• Shaddharana choorna
• Kaisora guggulu
• Rasna guggulu
• Guggulutiktaka ghrita
• Madhuyashtyadi taila – samana matra
• Nimbamrita eranda – samana matra
• Vardhamana pippali prayoga

Procedures

• Lepana – Kottamchukkadi in Dhanyamla
• Rooksha sweda
• Dhara – Dashamoola ksheera dhara / Dhanyamla dhara
• Virechana - Nirgundi eranda
• Vasti – Ksheera vasti, Ardha matrika vasti