Psoriatic Arthritis

Psoriatic Arthritis

1. Aetiology

   • Exact cause unknown, research suggests something (infection?) acts as a trigger in people who are susceptible to this arthritis

2. Pathology

   • PsA is an inflammatory arthritis associated with psoriasis. symptoms range from mild to severe - the typical rheumatic symptoms being joint stiffness, pain and swelling, and tenderness of ligament and tendon insertions. Although traditionally perceived as a mild disorder, about 2/3rds of people with PsA have progressive, damaging arthritis.

3. Diagnostic criteria (> 6 for PsA)

   • Back pain at night or stiffness in the morning (1)
     • Asymmetric oligoarthritis (2)
       • Gluteal pain without other details (1) or Alternating gluteal pain (2)
         • Sausage digit or toe (2)
           • Heel pain or other enthesopathy (2)
             • Iritis (2)
               • Diarrhoea within 1 month onset of arthritis (1)
                 • Sacroiliitis (3)
                   • Presence of HLA-B27 antigen and/or positive family Hx of AS, ReA, psoriasis, uveitis or chronic bowel disease (2)

4. Treatment

   • Medical management Control Inflammation
     • Pain management
       • Analgesics
     • NSAIDS
     • DMARDS (Sulfasalazine & Methotrexate) if not responding to 2 either in combination or alone use cheapest biologic
       • Biologic therapy
         • Review in 12 weeks for improvement of: Atleast 2/4 PsARC criteria(1 of which has to be joint tenderness and swelling score) & no worsening in any of 4 criteria.
           • If Pt has no response to PASI (Psoriasis Area and Severity Index) Discontinue Anti-TNF inhibitor used
   • Surgery
   • Podiatric management
     • Foot orthoses
       • Active enthesitis (Offload areas)
       • Tenosynovitis particularly Tib post (Medial heel wedge)
       • Poor rear foot alignment, low MLA, residual foot impairments even when disease activity has been suppressed (offload/realign accordingly)
     • Skin/Nail/ Lesion care/ Self management, Hygiene advice
     • Footwear advice
     • Excercises
       • Strengthening muscles eg Tib post
       • Stretches
     • IA Steroids
       • Tx for Dactlyitis/ Enthesitis
     • Long term Mx
       • Decrease foot pain, increase physical function, increase Health related QoL

5. Differential diagnosis

   • MSK conditions
     • PF
     • AT
     • Tib Post
   • Nails
     • Fungal
     • O/X
   • Other seronegative spondylarthropathy (AS)

6. Referralls

   • Orthotist
     • Assessment of biomechanical deficits (Functional problems)
     • Design, manufacture, delivery & review of orthotses (orthopaedia aids) and footwear
   • General practitioner
     • First contact
     • Diagnosis/referral
     • Initiate treatment
     • Long-term condition/co-morbidities management
   • Occupational therapist
     • Maintaining activities of daily living
     • Education, with provision of aids and coping skills
   • Physiotherapist
     • maintaining functional ability
     • musculoskeletal assessment
     • pain management and patient education

7. Assessment

   • Peripheral joint assessment
     • 66/68 tender/swollen joint count
     • DAS
     • PSARC
     • ACR response criteria
   • Enthesitis assessment
     • Leeds enthesitis Index (LEI)
       • 6 sites: Bilateral AT insertions, Bilateral medial femoral condyles, Bilateral lateral epicondyles of the humerus
   • Dactylitis assessment
     • Leeds dactylitis index (LDI)
       • 0-3Scale. 0=no tenderness. 1= tender. 2= tender + wince. 3= tender + withdraw