How do you examine a patient for enthesitis?

How to Examine for Enthesitis

Examine enthesitis by systematically palpating specific anatomical sites where tendons, ligaments, and joint capsules insert into bone, assessing for tenderness, swelling, or pain at these locations using a standardized scoring system.

Anatomical Sites to Examine

The examination should focus on easily accessible entheses using validated scoring systems. The most commonly used indices include:

Maastricht Ankylosing Spondylitis Enthesitis Score (MASES) Sites 1

• First costochondral joints (bilateral)
• Seventh costochondral joints (bilateral)
• Posterior superior iliac spines (bilateral)
• Anterior superior iliac spines (bilateral)
• Iliac crests (bilateral)
• Proximal insertion of Achilles tendon (bilateral)
• Fifth lumbar spinous process

Additional Sites for Comprehensive Assessment 2, 3

• Lateral epicondyles of humerus (bilateral)
• Medial epicondyles of humerus (bilateral)
• Greater trochanters (bilateral)
• Quadriceps insertions at superior patellar pole (bilateral)
• Patellar ligament insertions at inferior patellar pole (bilateral)
• Plantar fascia insertions at calcaneus (bilateral)

Examination Technique

Palpation Method 2, 3

• Apply firm, direct pressure over each enthesis site
• Assess the patient's response to palpation (verbal or facial expression indicating pain)
• Document presence of tenderness, swelling, or warmth at each site
• Score each site as either present (1 point) or absent (0 points) for tenderness 2, 4

Clinical Definition of Active Enthesitis 1, 5

• Tenderness at the enthesis site on palpation
• Swelling of the enthesis (visible or palpable)
• Patient-reported symptoms requiring medical treatment per provider judgment 1

Scoring and Documentation

Calculate Total Enthesitis Score 1, 2, 4

• Sum the number of tender entheses from all examined sites
• Higher scores indicate more severe enthesitis
• The enthesitis score correlates with pain (r = 0.67) and stiffness (r = 0.46) in ankylosing spondylitis 2

Associated Clinical Findings 1, 3

• Document inflammatory back pain if present (pain with direct palpation of sacroiliac joints)
• Assess for dactylitis (sausage digits) in hands or feet
• Evaluate for peripheral arthritis in adjacent joints
• Record impact on function and quality of life 3

Imaging Confirmation When Needed

Ultrasound Assessment 1, 5

• Power Doppler ultrasound can detect active inflammation with sensitivity 0.76-0.98 and specificity 0.48-0.94 1
• Useful when clinical examination is equivocal or to confirm diagnosis 1, 5

MRI Assessment 1, 6

• MRI is sensitive for detecting early enthesitis and intraosseous abnormalities 6
• Particularly valuable for heel enthesitis (specificity 0.94, though sensitivity only 0.22) 1
• Can evaluate both soft-tissue changes and bone marrow edema 6

Common Pitfalls to Avoid

Distinguishing from Other Conditions 3, 4

• Fibromyalgia coexists in ≤20% of patients and may cause widespread tenderness that mimics enthesitis 3
• Degenerative enthesopathy must be distinguished from inflammatory enthesitis—MRI can help differentiate 6
• Enthesitis severity does not correlate with laboratory markers (ESR, CRP), so normal inflammatory markers do not exclude active enthesitis 4

Assessment Considerations 2, 3, 4

• Enthesitis assessment is subjective and relies on patient-reported pain response 4
• Should be combined with objective spinal measurements when assessing overall disease activity 4
• The examination is reliable and reproducible when performed systematically 2, 3