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FOCUSED SHIFT VIEW

Acute Joint Pain

The hot swollen joint is septic until drained otherwise.

Open full pathway
Educational first-pass aid. Reassess the patient, confirm doses and use local protocols.

1 · First minutes

  1. A single hot joint is septic until the tap says otherwise.
  2. Aspirate before antibiotics when safe: Gram stain, culture, crystals, cell count.
  3. Crystals do not exclude infection.

2 · Escalate now if

  • Fever with a hot swollen joint
  • Prosthetic joint involved
  • Immunosuppression, diabetes, or IVDU
  • Inability to bear weight or move the joint
  • Overlying skin breaks or pustules
  • Synovial fluid that is purulent or Gram-stain positive (WBC >50,000/µL supports but does not prove infection)

3 · Immediate workup

  • Joint aspiration before antibiotics when possible: Gram stain, culture, crystals, cell count with differential
  • POCUS to confirm effusion and guide the tap

4 · Don’t miss

  • Septic arthritis
    Fever + hot joint (or an immunosuppressed/diabetic patient without fever) — aspirate before antibiotics when safe; IV therapy + washout. Synovial WBC >50,000/µL is suggestive, not diagnostic; gonococcal and immunocompromised septic joints are often well below that.
  • Prosthetic joint infection
    Any prosthesis + joint symptoms — urgent orthopedics. They perform the aspiration; do not tap through overlying cellulitis.
  • Fracture / osteomyelitis
    Trauma, diabetic foot, sickle cell — X-ray first; MRI for deep infection.

5 · Disposition lane

Admit

Septic arthritis on IV antibiotics + washout plan, polyarticular systemic disease, uncertain diagnosis needing serial exams.

Emergency aspiration/washout + ortho

Purulent joint, prosthetic infection, hemarthrosis with coagulopathy.