Patient Assessment: Ankylosing Spondylitis (AS)

1. History

Chief Complaint Pattern - Inflammatory Back Pain (IBP)

• Insidious onset, typically before age 40 years
• Morning stiffness lasting >30 minutes
• Pain improves with exercise, not rest
• Pain worse in the second half of the night (wakes the patient)
• Alternating buttock pain (reflecting sacroiliac involvement)
• Prevalence 3-6% of the population; only a minority progress to AS

Red Flags to Distinguish from Mechanical Back Pain

Extra-Articular History - Ask About:

• Eyes: Anterior uveitis (acute, unilateral, photophobia, eye pain) - occurs in up to 40% of AS patients
• Skin: Psoriasis (scalp, gluteal fold, umbilical area)
• Bowel: Inflammatory bowel disease (~10% of AS patients)
• Peripheral joints: Hip, knee, ankle pain; heel pain (enthesitis)
• Cardiac: Symptoms of aortic insufficiency, palpitations (conduction defects)
• Pulmonary: Dyspnea (apical pulmonary fibrosis - upper lobe bilateral reticulonodular infiltrates)

2. Physical Examination

Axial Skeleton Assessment

Sacroiliac Joint Tests

• FABERE test (Patrick's sign): Patient supine; hip flexed, abducted, and externally rotated; pain in SI joint region is positive
• Gaenslen maneuver: Hip extended off edge of table; stress on SI joint reproduces buttock/back pain
• Note: SI joint tenderness tests lack sensitivity and specificity and are not recommended as standalone criteria (Rheumatology 2022, Elsevier)

Peripheral Joint and Soft Tissue Exam

• Inspect/palpate for synovitis (swelling, warmth, effusion) - lower extremities predominate; hip involvement especially important (can lead to destructive arthropathy)
• Enthesitis sites: Achilles tendon, plantar fascia, elbow epicondyles, iliac crests, tibial tuberosities
• Dactylitis ("sausage digit") - uncommon in AS vs. psoriatic arthritis
• 44-joint count for peripheral joint assessment (per ASAS core set)

Extra-Articular Examination

• Eyes: Slit-lamp referral if uveitis suspected (urgent ophthalmology)
• Skin/nails: Check scalp, gluteal folds, umbilicus for psoriasis
• Cardiovascular: Aortic regurgitation murmur, bradycardia/heart block
• Respiratory: Reduced chest expansion, apical crackles

3. Laboratory Investigations

4. Imaging

• Grade 0: Normal
• Grade I: Suspicious
• Grade II: Minimal - sclerosis/erosion
• Grade III: Moderate - erosion, sclerosis, widening/narrowing
• Grade IV: Ankylosis (fusion)

5. Classification Criteria

ASAS Criteria for Axial SpA

6. Disease Activity Assessment Tools (ASAS Core Set)

ASDAS Cutoffs (most clinically used)

• <1.3: Inactive disease
• 1.3-2.1: Low disease activity
• 2.1-3.5: High disease activity
• >3.5: Very high disease activity
• Clinically important worsening = increase ≥0.9 points

ASAS Response Criteria

• ASAS-20: ≥20% improvement in 3 of 4 domains (function, pain, global, inflammation) with no worsening in the 4th
• ASAS-40: ≥40% improvement
• ASAS Partial Remission: Score <20/100 in all 4 domains

7. Differential Diagnosis

• Mechanical low back pain
• Diffuse idiopathic skeletal hyperostosis (DISH)
• Psoriatic arthritis (axial pattern)
• Reactive arthritis
• IBD-associated arthritis
• Osteitis condensans ilii
• Infectious sacroiliitis

8. Summary: Key Assessment Points

1. History: Insidious IBP before age 40, morning stiffness >30 min, nocturnal pain, alternating buttock pain, improvement with exercise
2. Physical exam: Modified Schober's, chest expansion, occiput-to-wall, lateral spinal flexion, FABERE/Gaenslen; peripheral joints and enthesis tenderness
3. Labs: HLA-B27, CRP/ESR, CBC; ANA/RF negative
4. Imaging: Plain X-ray pelvis first; MRI if early disease suspected or X-rays equivocal
5. Scoring: ASDAS and BASDAI for disease activity; BASFI for function; BASMI for mobility
6. Screen extra-articular features: Eyes, skin, bowel, heart, lungs

Physiotherapy Assessment: Ankylosing Spondylitis

1. Subjective Assessment (History)

Pain Assessment

• Location: Lumbar spine, sacroiliac joints, thoracic spine, cervical spine, peripheral joints, entheseal sites (heel, Achilles, plantar fascia, elbow)
• Character: Deep, aching - inflammatory pattern vs. mechanical
• Severity: NRS/VAS (0-10) for general spinal pain and spinal pain at night
• Timing: Morning stiffness - note duration (>30 min is significant), nocturnal pain, improvement with activity
• Aggravating/easing factors: Rest worsens (inflammatory pattern), exercise eases
• Alternating buttock pain: Flag as SI joint indicator

Stiffness

• Duration of morning spine stiffness (recorded in minutes) - this is a formal ASAS outcome measure
• Evening stiffness after prolonged sitting

Functional History

• Activities of daily living: dressing (socks/shoes), bathing, grooming (arms overhead), turning in bed
• Work demands: prolonged sitting/standing, manual handling, computer work
• Leisure/sport: impact on hobbies, swimming, walking
• Ask with the BASFI framework: reaching, picking up objects from floor, stairs, prolonged standing, rising from floor

Fatigue

• Use VAS from the BASDAI - fatigue is a major patient-reported concern in AS
• Timing and relationship to activity and sleep quality

Respiratory History

• Breathlessness on exertion
• History of chest infections or reduced respiratory reserve
• Smoking history (worsens apical fibrosis)

Psychosocial Screen

• Impact on employment, mood, social participation
• Sleep disturbance, depression, anxiety (common co-morbidities)
• Illness beliefs and self-efficacy for exercise

Current and Previous Treatments

• Current medications (NSAIDs, biologics, DMARDs) and response - note: NSAIDs reduce pain/stiffness and facilitate physiotherapy (Rheumatology 2022, Elsevier)
• Previous physiotherapy, hydrotherapy, or spa-exercise therapy and response
• Home exercise compliance

2. Objective Assessment

2a. Postural Observation

• Hyperkyphosis of thoracic spine (increased thoracic kyphosis is the classic late deformity)
• Loss of lumbar lordosis
• Forward head posture / protruding chin
• Occiput-to-wall distance as a postural measure (normal = 0 cm; heels and back flat on wall)
• "Bamboo spine" posture in advanced disease - rigid, fixed kyphotic posture
• Shoulder and hip flexion contractures
• Gait: forward stooped posture, reduced arm swing, antalgic pattern

2b. Spinal Mobility Measures (ASAS Core Set)

1. Lateral lumbar flexion
2. Tragus-to-wall distance
3. Cervical rotation
4. Modified Schober's test
5. Intermalleolar distance

2c. Hip Assessment

• Hip range of motion (flexion, extension, internal/external rotation, abduction) - hip involvement occurs in up to 30% and can progress to destruction
• FABERE test (Patrick's test): hip flexion + abduction + external rotation reproduces SI joint or hip pain
• Thomas test for hip flexion contracture
• Hip flexion contracture contributes to increasing stoop - may be misattributed to spinal involvement alone (Goldman-Cecil Medicine)

2d. Peripheral Joint Assessment

• Swollen joint count (44-joint count per ASAS core set)
• Inspection/palpation: swelling, warmth, effusion, range of motion
• Common peripheral joints in AS: hips, knees, ankles, shoulders

2e. Enthesitis Assessment

• Achilles tendon insertions (bilateral)
• Plantar fascia (calcaneal attachment)
• Iliac crests
• Tibial tuberosities
• Elbow epicondyles
• Greater trochanters

2f. Respiratory Assessment

• Chest expansion is the most clinically accessible measure (target >5 cm)
• Breathing pattern observation: Use of accessory muscles, diaphragmatic breathing pattern, ribcage vs. abdominal movement
• Auscultation: Apical crackles (fibrobullous disease in advanced AS)
• Dyspnea on exertion: 6-Minute Walk Test (6MWT) - excellent physiotherapy-specific outcome

2g. Muscle Strength and Endurance

• Trunk extensor and flexor strength - back extensor weakness contributes to flexed posture
• Hip extensor and abductor strength - important for gait and posture
• Shoulder and upper limb strength if cervical/thoracic involvement
• Hand grip dynamometry if peripheral involvement
• Core stability testing

2h. Aerobic Capacity and Exercise Tolerance

• 6-Minute Walk Test (6MWT): measures functional exercise capacity; a key outcome in exercise therapy trials
• VO2 peak (cardiopulmonary exercise testing if available): aerobic capacity is reduced in AS due to chest wall restriction and physical deconditioning (Fishman's Pulmonary Diseases)
• Evidence: A 2025 systematic review and meta-analysis (Zhang et al., Arch Phys Med Rehabil, PMID 38942347) of 20 RCTs (n=1,670) showed exercise therapy significantly improved VO2 peak (WMD +3.16 mL/kg/min) and 6MWT distance (WMD +27.64 m) compared to controls

2i. Balance and Falls Risk

• Increased falls risk due to rigid spine, impaired rotation, and head/neck position
• Single-leg stance test
• Functional reach test
• Note: inability to rotate or extend to see behind - relevant to road safety (driving assessment)

3. Patient-Reported Outcome Measures (PROMs) for Physiotherapy

4. Goal Setting for Physiotherapy (Informed by Assessment)

5. Key Evidence for Exercise Therapy

• BASFI: WMD -0.49 (95% CI -0.65 to -0.32) - function
• BASMI: WMD -0.49 (95% CI -0.87 to -0.11) - mobility
• BASDAI: WMD -0.78 (95% CI -1.08 to -0.47) - disease activity
• ASDAS: WMD -0.44 - composite activity
• Pain: SMD -0.47 and fatigue: SMD -0.49
• VO2 peak and 6MWT also significantly improved
• No significant effect on chest expansion, CRP, or ESR

6. Red Flags / Referral Indicators During Physiotherapy Assessment

Physiotherapy Management: Ankylosing Spondylitis

Overarching Principles (ASAS/EULAR Guidelines)

• "Patients should be educated about axial SpA and encouraged to exercise on a regular basis and stop smoking; physical therapy should be considered" - Level of Evidence 2/1A, Grade B/A, mean agreement 9.8/10 (Firestein & Kelley's Textbook of Rheumatology)
• "The optimal management requires a combination of nonpharmacological and pharmacological treatment modalities" - agreement 9.8/10
• "The goals of physical therapy are to restore and maintain posture and movement as nearly normal as possible. Self-management with exercises must be continued on a lifelong basis" (Rheumatology 2022, Elsevier)
• Physiotherapy is not an adjunct - it is first-line, lifelong treatment that runs in parallel with pharmacotherapy

1. Exercise Therapy - The Core Intervention

Hierarchy of Delivery (Evidence-Based)

Exercise Categories and Specific Recommendations

A. Flexibility and Stretching Exercises

• Daily spinal extension and lateral flexion stretches
• Cervical rotation and lateral flexion mobilisations
• Hip flexor stretching (Thomas test stretch position) - essential given hip flexion contracture risk
• Thoracic rotation exercises
• Shoulder girdle mobilisation
• Can be performed daily - low risk, highly beneficial

B. Strengthening Exercises

• Back extensor muscle strengthening - most important; directly opposes the forward-flexion deformity progression. "Physical therapy focusing on strengthening of back extensor muscles might improve functional status and, at the very least, help maintain an erect position if spinal ossification occurs" (Textbook of Family Medicine 9e)
• Hip extensor and abductor strengthening
• Scapular retractor and posterior shoulder strengthening
• Core stability and transversus abdominis activation
• Quadricep and lower limb strengthening for functional capacity
• Perform 2-3 times per week, with progressive loading

C. Aerobic/Endurance Exercises

• Swimming is the preferred sport/exercise in AS - buoyancy offloads the spine, allows full range of motion, and the prone position encourages spinal extension. "Patients should be encouraged to swim for exercise" (Textbook of Family Medicine 9e)
• Cycling (stationary or road)
• Walking programmes - graduated intensity
• Aim for 30 minutes, several times weekly
• Aerobic exercise improves VO2 peak, 6MWT distance, and fatigue

D. Aquatic Exercise (Hydrotherapy)

• Warm water reduces pain and stiffness, facilitating greater range of motion
• Buoyancy enables exercises that would be painful on land
• Combines aerobic, stretching, and strengthening in one session

• Aquatic Stretching Exercise (ASE) ranked #1 for:
  • BASDAI (SUCRA 85.5%) - disease activity
  • BASFI (SUCRA 99.6%) - function
  • ASQoL (SUCRA 88.4%) - quality of life
• Land Aerobic Exercise ranked #2 across most outcomes
• ASE is the most effective single exercise modality for symptom relief, functional enhancement, and quality of life improvement in AS

E. Mind-Body and Specialty Exercises

• Pilates: Aerobic exercise + Pilates ranked highest for BASDAI and BASMI in a 2025 network meta-analysis (PMID 41640843, 32 RCTs)
• Tai Chi / Yoga: Evidence supports benefits for pain, function, and fatigue - systematic reviews confirm efficacy for mind-body exercise in axSpA (PMID 39342350)
• China Health Campaign (Qigong/Wushu-type): Ranked highest for BASMI improvement (SUCRA 78.7%) in the 2025 NMA
• Hippotherapy simulation: Most effective for BASFI improvement in the 2025 NMA

Exercise Dosage Principles

2. Postural Training

• Loss of lumbar lordosis → lumbar kyphosis
• Increased thoracic kyphosis (hyperkyphosis)
• Forward head posture / cervical protrusion
• Hip and knee flexion contractures (compensatory)
• "Bullet belly" in severe late-stage disease (Firestein & Kelley's)

Postural Correction Strategies

• Extension-biased positioning: Exercises and daily habits favouring spinal extension
• Prone lying: 20-30 minutes per day to counteract flexion deformity (on firm surface)
• Wall standing: Heels, buttocks, shoulders, and occiput against wall - passive extension stretch
• Sleeping advice: Firm mattress; minimal pillow use or no pillow; avoid cervical flexion
• "Patients should be encouraged to walk erect and to keep the spine erect as much as possible, sleep on a firm mattress with the spine extended" (Textbook of Family Medicine 9e)
• Ergonomic advice: Workstation setup to avoid prolonged flexed posture; avoid deep soft armchairs; car seat positioning
• Cervical extension exercises: To counteract chin-to-chest deformity tendency

3. Breathing Exercises and Respiratory Physiotherapy

• Chest expansion is directly reduced (target >5 cm, often significantly reduced in AS)
• Diaphragmatic breathing and limited chest excursion are typical findings
• Aerobic capacity limited by chest wall rigidity (Goldman-Cecil Medicine)

Respiratory Physiotherapy Interventions

• Diaphragmatic (abdominal) breathing training: Compensates for reduced rib cage movement
• Lateral costal breathing exercises: Expand the upper and lower rib cage
• Deep breathing exercises: Timed inspiratory holds (3-5 seconds), slow exhalation
• Incentive spirometry if chest expansion is severely reduced
• Inspiratory muscle training (IMT): Threshold loading devices to strengthen diaphragm and intercostals
• Segmental breathing: Directed at specific restricted areas of the chest wall
• Smoking cessation support: Smoking independently accelerates lung damage in AS; "patients should stop smoking" (Grade A recommendation)
• Breathing exercises are performed daily, integrated into morning and evening exercise sessions

4. Patient Education and Self-Management

Core Education Topics

Self-Management Skills

• Independent daily home exercise programme
• Self-monitoring with BASDAI/BASFI (patient-completed) to detect flares
• Gradual progression of exercise load
• Long-term integration into community-based exercise groups (Rheumatology 2022)

5. Hydrotherapy / Spa-Exercise Therapy

• Inpatient spa programme (group exercises, walking, hydrotherapy, sports, sauna) followed by supervised outpatient weekly group physiotherapy = best results vs. weekly physiotherapy alone (Textbook of Family Medicine; van Tubergen et al. RCT)
• Warm water (34-36°C) reduces muscle spasm and joint stiffness, allowing maximal mobility work
• Cost-effectiveness data also support combined spa-exercise therapy

6. Exercise Delivery Models

Progression Framework

Phase 1 (Acute/Active Inflammation)
  - Gentle range-of-motion exercises within pain tolerance
  - Breathing exercises
  - Postural advice
  - Hydrotherapy preferred over land-based
  - Avoid high-impact or forceful loading

Phase 2 (Stable Disease - Building Phase)
  - Progressive strengthening (back extensors, hips, core)
  - Aerobic conditioning (graded walking, cycling, swimming)
  - Supervised group exercise or hydrotherapy
  - Daily flexibility programme continued

Phase 3 (Maintenance - Lifelong)
  - Independent home programme + community group exercise
  - Regular review and progression
  - Monitor with BASMI, BASFI, chest expansion
  - Reassess goals at each review

Group vs. Individual Exercise

• Supervised group exercise outperforms individual home exercise
• Group provides: peer support, adherence motivation, supervision for technique
• Goal: transition from supervised to independent home/community programme (Rheumatology 2022)

7. Special Considerations

Fracture Risk

• Ankylosed spine has brittle, rigid segments - vulnerable to fracture from minor trauma
• Avoid high-impact, contact sports or activities involving rapid uncontrolled spine rotation
• Avoid cervical hyperextension during exercise
• Patient must understand that a fall or minor trauma warrants urgent imaging

Hip Involvement

• Hip physiotherapy: range-of-motion exercises, hydrotherapy, gait retraining
• If hip arthroplasty considered - pre- and post-operative physiotherapy is essential

Psychological Co-morbidity

• Depression and anxiety are common in AS - address as part of holistic management
• Exercise itself has proven antidepressant and anti-fatigue effects
• Consider referral to pain psychology or cognitive-behavioural approaches if indicated

Driving and Safety

• Restricted cervical and thoracic rotation significantly impairs the ability to check blind spots
• Occupational therapy and driving assessment may be required in advanced disease

8. Outcome Monitoring in Physiotherapy

Evidence Summary Table

Physiotherapy Management: Ankylosing Spondylitis (Quick Reference)

Core Principle

1. Exercise (Priority Order)

2. Postural Training

• Prone lying 20-30 min/day
• Wall standing - extension stretch
• Sleep: Firm mattress, minimal pillow, supine/prone
• Avoid: Prolonged flexed postures, deep soft chairs
• Teach erect gait and spinal extension habits

3. Breathing Exercises

• Diaphragmatic breathing training (daily)
• Lateral costal expansion exercises
• Deep breathing with inspiratory hold
• Inspiratory muscle training if chest expansion severely reduced
• Smoking cessation - Grade A recommendation

4. Patient Education

• Exercise is essential, lifelong - explain WHY
• Flare management: reduce intensity, don't stop
• Fracture risk awareness (minor trauma = urgent imaging)
• Ergonomic workstation advice
• Swimming as preferred recreation

5. Outcome Measures (Monitor Every 3-6 Months)

Key Evidence (2025)

• Aquatic stretching = #1 modality for disease activity, function, QoL (Kong et al. NMA, 48 RCTs)
• Flexibility + strength = largest effect on spinal mobility (Boudjani et al. MA)
• Exercise improves BASFI, BASMI, BASDAI, pain, fatigue, VO2 peak (Zhang et al. MA, 20 RCTs)