🩹 Psoriatic Arthritis Joint Involvement Simulator

Dactylitis: The Psoriatic "Sausage Digit"

Whole-digit swelling is a hallmark feature distinguishing PsA from rheumatoid arthritis.

• ~40%: Prevalence in PsA (placeholder statistic)
• Toes: Most affected digit (placeholder statistic)
• Asymmetric: Onset pattern (placeholder statistic)
• Flexor tenosynovitis: Imaging finding (placeholder statistic)

What drives sausage digit swelling

Placeholder: combined joint and tendon sheath inflammation causes diffuse digit swelling.

Enthesitis: Inflammation at Tendon Insertions

Entheseal inflammation is a core feature linking PsA to the spondyloarthritis family.

• Achilles: Common site (placeholder statistic)
• ~35%: Prevalence (placeholder statistic)
• Ultrasound: Detection tool (placeholder statistic)
• Insertional: Pain pattern (placeholder statistic)

Why entheses become inflamed

Placeholder: mechanical stress plus immune activation targets tendon-bone junctions.

Axial Spondylitis in Psoriatic Arthritis

Spinal and sacroiliac joint inflammation causes inflammatory back pain in a subset of patients.

• ~25%: Axial PsA prevalence (placeholder statistic)
• Sacroiliac: Key joint (placeholder statistic)
• Syndesmophytes: Imaging sign (placeholder statistic)
• Morning stiffness: Symptom pattern (placeholder statistic)

How axial disease progresses

Placeholder: chronic inflammation drives new bone formation along the spine.

Conventional DMARD Therapy Effects

Conventional synthetic DMARDs reduce peripheral joint inflammation with partial efficacy.

• Methotrexate: Common agent (placeholder statistic)
• ~40-50%: Response rate (placeholder statistic)
• Limited: Axial efficacy (placeholder statistic)
• 6-12 weeks: Onset of effect (placeholder statistic)

What DMARDs do and do not treat

Placeholder: effective for peripheral synovitis, weak for axial and entheseal disease.

Biologic Therapy and Structural Joint Protection

Targeted biologics such as TNF and IL-17 inhibitors slow joint damage progression.

• TNF / IL-17: Target pathway (placeholder statistic)
• ~60-70%: Response rate (placeholder statistic)
• Slows erosion: Radiographic effect (placeholder statistic)
• Strong: Axial efficacy (placeholder statistic)

Why biologics protect joint structure

Placeholder: blocking key cytokines reduces inflammation and limits bone/cartilage damage.

Placeholder: early biologic treatment improves long-term joint outcomes.