Arthrocentesis

Indications

Diagnosis

• suspicion of septic arthritis, crystal induced arthritis
• evaluation of therapeutic response for septic arthritis
• unexplained arthritis with synovial effusion

Relative Indications

Therapeutic (decrease intra-articular pressure, injection of anesthetics/steroids)

Contraindications

1. No absolute contraindications for diagnostic arthrocentesis
2. do not inject steroids into a joint that you suspect or know to be infected
3. Relative Contraindications:
   1. coagulopathy
   2. local or systemic infection
   3. Joint prosthesis (refer to ortho)

Equipment Needed

1. Betadine or Chlorhexadine
2. Sterile Gloves/drape
3. sterile gauze
4. Lidocaine
5. Syringes
   1. small syringe (6-12cc) for injection of local anesthetic
   2. Large (one 60cc or 2 30cc) syringe for aspiration
6. Needles
   1. 18 gauges
   2. 27 gauge
7. Collection tubes (red tops)
8. Culture bottles
9. adhesive bandage

Procedure

1. Position the patient in a way so that they are comfortable and so you have easy access to the joint that you are going to tap (see below for positioning pearls)
2. Prep the area with betadine or chlorhexadine using circular motion moving away from the joint x 3. Drape the joint in a sterile fashion
3. Inject lidocaine superficially and then into the deeper tissues
4. Confirm landmarks and then insert the needle into the joint space while you are simultaneously pulling back on the plunger of the syringe. Stop once you aspirate fluid and aspirate as much fluid as possible (you may need to replace the syringe multiple times to get larger volumes)
5. Once fluid is removed, remove the needle and apply adhesive bandage

Approach

Shoulder

1. anterior approach: have patient sitting with should in external rotation. Insert needle anteriorly below the tip of the coracoid medial to the humeral head directing it posterolaterally
2. posterior approach: same as anterior approach except needle is inserted on the posterior side of the shoulder

Elbow

1. Have patient sitting with elbow in 90 degrees of flexion, forearm pronated, palm facing downward
2. insert needle within triangle bounded by radial head, lateral humeral epicondyle, and olecranon directing it toward the medial epicondyle

Wrist

1. 3-4 portal approach: have wrist in slight flexion and ulnar deviation. Insert needle dorsally just distal to Lister's tubercle (bony prominence over the dorsum of the distal radius) and ulnar to the extensor pollicus longus

Metacarpophalangeal

1. have palm facing down and apply gentle traction to the affected digit
2. insert needle dorsally just medial or lateral to midline and proximal to the base of the proximal phalanx

Interphalangeal

1. have palm facing down and apply gentle traction to the affected digit
2. insert needle dorsally medial or lateral to midline and proximal to base of middle or distal phalanx

Knee

1. Inferior-medial approach: knee flexed at 90 degrees and needle inserted between patella tendon, medial femoral condyle, and medial tibial plateau
2. Medial approach: knee extended and needle inserted 1-2cm medial to patella just distal to proximal edge of the patella directing it posteriorly beneath the patella

Ankle

1. plantarflex the ankle and locate the medial malleolus and anterior tibialis tendon
2. Insert needle 1/2 inch above medial malleolus, 1/2 inch lateral to anterior edge of medial malleolus, and medial to the anterior tibialis tendon advancing it posteriorly

Metatarsophalangeal

1. patient supine with flexion of the MTP joint 15-20 degrees and apply gentle traction
2. insert needle dorsally just medial or lateral to midline between the metatarsal head and base of proximal phalanx

Interphalangeal

1. patient supine with joint flexed 15-20 degrees with gentle traction
2. insert needle dorsally, medial or lateral to midline between head of proximal phalanx and base of more distal phalanx

Complications

1. pain
2. infection
3. reaccumulation of effusion
4. damage to tendons, nerves, or blood vessels

See Also

Septic Arthritis (General)

Monoarticular Arthritis

Septic Arthritis (Hip)

Septic Arthritis (Peds)

Source

http://emprocedures.com/arthrocentesis/introduction.htm