II. Indication
- Aspiration
- Knee Effusion of unclear etiology
- Evaluation for Septic Knee
- Injection (Synvisc or Corticosteroid)
- Knee Osteoarthritis
- Gouty Arthritis affecting the knee
- Pseudogout affecting the knee
III. Preparation
- Needle
- Gauge: 25-27 (injection), 18-20 (aspiration)
- Length: 1.5 inches
- Syringe: 10 ml (injection) or 30-60 ml (aspiration)
-
Corticosteroid options
- Betamethasone (Celestone) 2 ml of 6 mg/ml
- Methylprednisolone (Depo-Medrol): 2 ml of 40 mg/ml
- Anesthetic
- Lidocaine 1%: 5 to 7 ml or
- Bupivacaine 0.25% or 0.5%: 5 to 7 ml
IV. Technique
- Images
- Patient position
- Patient supine with knee in slight flexion
- Prop up knee on towel roll in popliteal space
- Sterilize local skin with Betadine or Hibiclens
- Mark needle insertion site based on approach
- Lateral Suprapatellar Approach
- Medial Suprapatellar Approach
- Knee flexed 60-90 degrees
- Insert needle medial to Patellar tendon
- Stay parallel to tibial plateau
- Risk of Meniscus Injury
- Medial Approach
- Risk of hitting medial meniscus (uncommon)
- Aspirate first, then inject
- Inferior Approach
- Patient sits with knee at 90 degrees
- Allows fluid to settle into dependent position
- May localize small effusion to allow aspiration
- Insert needle just medial to inferior Patellar pole
- Patient sits with knee at 90 degrees
- Aspirate first and then inject
- Use first syringe to aspirate joint contents
- Use hemostat to detach syringe from needle
- Attach syringe with Corticosteroid
- Inject Corticosteroid mix into joint
V. References
- Pfenninger (1994) Procedures, p. 1036-54
- Cardone (2003) Am Fam Physician 67(10):2147-52 [PubMed]
- Zuber (2002) Am Fam Physician 66(8):1497-1500 [PubMed]
