Arthrocentesis (Joint Aspiration): Indications, Technique, and Risks

Arthrocentesis = needle puncture of a joint space for diagnostic or therapeutic purposes.

Diagnostic Indications

• Septic arthritis (cell count, Gram stain, culture)
• Crystal arthropathy (gout – MSU crystals; pseudogout – CPP crystals)
• Inflammatory arthritis (RA, spondyloarthropathy)
• Hemarthrosis (trauma, coagulopathy)
• Unexplained monoarthritis

Therapeutic Indications

• Drain large effusion (pain relief, improved ROM)
• Intra‑articular corticosteroid (inflammation)
• Hyaluronic acid (OA viscosupplementation)
• Antibiotics (septic joint)
• Emerging: PRP, stem cells

Procedure Outline

1. Informed consent; identify landmarks.
2. Sterile prep; local anesthetic (1% lidocaine).
3. Needle insertion (approach varies by joint).
4. Aspirate fluid → send for analysis.
5. Inject medication if indicated.
6. Bandage; brief observation.

Risks (Low)

• Infection (septic arthritis) ~1/10,000–1/50,000
• Bleeding, nerve injury, cartilage damage
• Post‑injection flare (crystals/steroid)