🧠 Memory Hook
RA = Relentless Autoimmune Synovitis
The Five S's of RA:
Symmetrical
Small joints
Synovium
Stiffness
Systemic
Section 13 marksDefinition
Section 24 marksAetiology
Section 36 marksClinical
Section 43 marksInvestigations
Section 52 marksManagement
Osteo + RF2 marksSafety
Section 1: Definition 3 marks
Rheumatoid Arthritis (RA) is a progressive chronic inflammatory disorder of unknown aetiology, primarily affecting the synovium of diarthrodial joints.
- Prevalence: ~1% of the population
- Peak onset: 35–55 years
- Sex ratio: Female > Male, 3:1
- Genetic associations: HLA-DR4 and HLA-DR3
- Characterised by symmetrical polyarthritis with systemic extra-articular features
📚 Ref: ICOM Rheumatology and Orthopaedics Overview, Year 4 notes
Section 2: Aetiology & Pathology 4 marks
Four aetiological theories:
Hormonal
Infective
Genetic
Immunological
Rheumatoid Factor (RF): IgM antibody — not specific to RA. Patient is seropositive if RF present. High RF levels correlate with severe disease including: nodules, vasculitis, Sjögren's, neuropathy, lung involvement, and Felty's syndrome.
Pathological Cascade:
Immune complexes
→
↓ T-suppressor activity
→
Macrophage activation
→
Neutrophil phagocytes
→
Proteolytic enzymes
→
Prostaglandins
→
Pannus formation
→
Cartilage destruction
→
Joint subluxation
📚 Ref: ICOM Rheumatology notes; Kumar & Clark Clinical Medicine 10th ed, Elsevier 2021
Section 3: Clinical Presentation 6 marks
Core features: Morning stiffness lasting 20–30 minutes after inactivity; symmetrical polyarthritis affecting small joints of hands and feet (PIPJ, DIPJ, MTPJ, wrist — 80% of cases).
Hand Deformities:
| Deformity | Description |
|---|
| MCP subluxation | Metacarpophalangeal joint subluxation |
| Ulnar deviation | Fingers deviate ulnarly at MCP joints |
| Swan neck | PIP hyperextension + DIP flexion |
| Boutonnière | PIP flexion + DIP hyperextension |
| Z-thumb | IP hyperextension + MCP flexion |
| Extensor tendon rupture | Loss of active extension |
| Ulnar styloid erosion | Prominent ulnar styloid, piano key sign |
Foot Deformities:
- MTPJ subluxation with callus formation
- Prominent metatarsal heads — "walking on marbles" sensation
- Hallux valgus
- Valgus midfoot deformity
Extra-articular Features:
| System | Features |
|---|
| Skin | Rheumatoid nodules (extensor surfaces), vasculitis, palmar erythema |
| Eyes | Sjögren's syndrome (dry eyes/mouth), scleritis, episcleritis |
| Lungs | Pleural effusion, fibrosing alveolitis, Caplan's syndrome |
| Heart | Pericarditis, pericardial effusion |
| Haematology | Felty's syndrome (RA + splenomegaly + neutropenia), anaemia of chronic disease |
| Neurology | Peripheral neuropathy, carpal tunnel syndrome, cervical myelopathy |
📚 Ref: ICOM Rheumatology and Orthopaedics Overview, Year 4 notes
Section 4: Investigations 3 marks
| Investigation | Finding / Significance |
|---|
| RF (latex agglutination) | Positive in ~80%; not specific to RA |
| Anti-CCP antibodies | More specific than RF; early marker |
| FBC | Normochromic normocytic anaemia; raised WBC in flare |
| ESR / CRP | Raised — markers of inflammation and disease activity |
| Synovial fluid | Raised WBC; turbid; low viscosity |
| X-ray (early) | Soft tissue swelling, periarticular osteoporosis, marginal erosions |
| X-ray (late) | Reduced joint space, erosions, subluxation, ankylosis, secondary OA |
📚 Ref: ICOM Rheumatology notes; NICE NG100 Rheumatoid Arthritis in Adults 2018 (updated 2023)
Section 5: Management & Prognosis 2 marks
Conservative: Patient education, physiotherapy, occupational therapy, splints/appliances, hydrotherapy
Pharmacological:
- NSAIDs — symptom control
- Steroid injections — local flare management
- DMARDs — Methotrexate first-line; sulfasalazine, hydroxychloroquine
- Biologics — Anti-TNF agents (etanercept, adalimumab) if DMARDs fail
- Immunosuppressants — azathioprine, ciclosporin
Surgical: Joint replacement, synovectomy, tendon repair
Prognosis: Persistent disease 75%; intermittent 25%. ~50% have little disability; ~10% develop severe disability.
📚 Ref: NICE NG100; Kumar & Clark Clinical Medicine 10th ed
⚠️ Osteopathic Safety — Cervical Spine in RA
- RA affects the cervical spine in 30–40% of patients
- Atlantoaxial instability — transverse ligament erosion allows C1 to slide on C2
- Odontoid peg erosion — risk of cord compression
- Mid-cervical facet erosion — subaxial instability
- Cervical HVLA is absolutely contraindicated unless instability has been excluded by imaging (flexion/extension X-ray or MRI)
Screen for myelopathy before ANY cervical treatment:
- Bilateral hand tingling / numbness
- Hyperreflexia (brisk DTRs)
- Gait disturbance / unsteadiness
- Positive Babinski sign
- Positive Hoffmann sign
- Bladder / bowel dysfunction
📚 Ref: ICOM Cervical and Thoracic Spine Assessment Year 4; ICOM Manipulation Notes Summary Scenario 3
🚩 Red Flags — Refer / Do Not Manipulate
- Bilateral hand tingling or weakness in an RA patient
- Any signs of myelopathy (hyperreflexia, Babinski, Hoffmann, gait disturbance)
- Sudden or severe neck pain in a known RA patient
- Bladder or bowel dysfunction
- Acute systemic flare with fever, raised inflammatory markers
- Progressive neurological deficit
📖 References
- ICOM Rheumatology and Orthopaedics Overview — Year 4 Google Classroom notes
- ICOM Cervical and Thoracic Spine Assessment — Year 4 notes
- ICOM Manipulation Notes Summary — Scenario 3
- NICE NG100. Rheumatoid Arthritis in Adults. 2018, updated 2023. nice.org.uk/guidance/ng100
- Kumar P & Clark M. Kumar & Clark's Clinical Medicine. 10th ed. Elsevier; 2021.
- DiGiovanna EL, Schiowitz S, Dowling DJ. An Osteopathic Approach to Diagnosis and Treatment. 3rd ed. Lippincott; 2005.