Rheumatology

Low-dose radiotherapy for painful osteoarthritis (especially hand and knee) is used in parts of Europe, particularly Germany, on the rationale of an anti-inflammatory effect.

Teriparatide is reserved for severe established osteoporosis. The PBS criteria capture the idea: BMD T-score of −3.0 or less, plus fracture despite at least 12 months of continuous antiresorptive therapy (bisphosphonate or denosumab).

• Trauma — including seemingly minor mechanisms.
• Autoimmune disease — rheumatoid arthritis, SLE, ankylosing spondylitis.
• Sexual history — disseminated gonococcal infection causes a migratory arthritis, tenosynovitis and pustular rash in young, sexually active patients.
• Recent viral or gastrointestinal/genitourinary illness — reactive arthritis classically follows infection by days to weeks.
• In children and adolescents: juvenile idiopathic arthritis — systemic JIA (Still's disease, with quotidian fevers and salmon-pink rash), oligoarticular and polyarticular subtypes.

• The atraumatic painful limb — no injury to explain the pain.
• The patient who cannot weight-bear.
• Neurovascular compromise.
• Crepitus beneath the skin — subcutaneous gas from gas-forming bacteria until proven otherwise (necrotising infection: urgent surgical review).

• Felty syndrome ("few cells") — RA + splenomegaly + neutropenia.
• Caplan syndrome ("coal") — RA + pneumoconiosis (classically coal workers) + intrapulmonary rheumatoid nodules.
• In the spine, RA most commonly affects the cervical spine — especially the atlanto-axial joint (C1–C2). Atlanto-axial subluxation risks cord compression: think of it before intubation or any procedure involving neck extension, and have a low threshold for imaging.

Think of Paget's in the older patient with localised bone pain, tibial bowing and an isolated raised ALP (with normal calcium and phosphate). Hearing loss occurs through bony expansion of the temporal bone compressing CN VIII.

A relatively newly described autoinflammatory condition (Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic) caused by a somatic mutation in UBA1 — occurs almost exclusively in older men. Think of it with recurrent fevers, chondritis (ear/nose), skin lesions, pulmonary infiltrates and unexplained cytopenias/macrocytic anaemia that doesn't fit a single rheumatological diagnosis — bone marrow biopsy shows characteristic cytoplasmic vacuoles in myeloid and erythroid precursors. Often mimics relapsing polychondritis or a myelodysplastic syndrome; management is largely supportive/immunosuppressive.

In a patient with a history of cocaine use presenting with purpura over the earlobes and limbs ± sinusitis or nasal septal destruction, think levamisole-induced vasculitis. Cocaine is commonly adulterated ("laced") with levamisole to enhance its stimulant effect.

• Work-up: ANCA (often strongly positive — classically p-ANCA/MPO, though dual MPO + PR3 positivity is a clue to levamisole), ANA and CRP.
• Skin findings favour cartilage-rich sites: earlobes, nose, cheeks.

Luxatio erecta is the inferior glenohumeral dislocation — rare (<1% of shoulder dislocations) and dramatic: the arm is locked in fixed, extreme abduction, as if the patient is asking a question. Check axillary nerve and vascular status; neurovascular injury is more common than in anterior dislocations.

A tear of the ulnar collateral ligament of the thumb MCP joint, classically from forced abduction (ski pole injury). Test pinch grip and valgus stability — a complete tear (Stener lesion) needs surgical referral.

Suspect with sudden anterior thigh pain, a palpable suprapatellar gap and inability to straight-leg raise. Ultrasound confirms the diagnosis when examination is equivocal.

• X-ray of the affected limb to look for a fracture.
• Bloods (FBC, CRP, ESR, blood culture) if septic arthritis or another infective cause is on the differential.
• Ultrasound of the joint — useful for detecting a joint effusion/collection or abscess, and can guide aspiration if septic arthritis is suspected.