Wrist arthrocentesis (ultrasound-guided)

Wrist arthrocentesis refers to the aspiration of an effusion in the radiocarpal joint. It serves primarily as a diagnostic modality to determine fluid composition, and may function secondarily to reduce pain associated with capsular stretch. The dynamic, ultrasound-guided technique will be described.

Indications

• diagnostic
  • identification of infectious or inflammatory etiologies in the presence of a joint effusion
  • hemarthrosis
• therapeutic
  • intra-articular administration of corticosteroids
  • diminished pain after drainage of tense effusion

Contraindications

• overlying cellulitis
• bacteremia

Procedure

The procedural steps are largely generalizable, and should be sought in detail in the arthrocentesis article. Specific points important in the wrist are discussed here.

Technique

Scanning typically begins over the dorsal, distal radius for pre-procedural anatomical landmark identification with the patient's hand typically pronated and wrist in slight passive flexion.

Sliding the transducer distally will reveal an effusion, if present, overlying the scaphoid and/or lunate in the proximal carpal row. Identification of Lister's tubercle and the immediately radial second extensor compartment are important sonographic landmarks for the commonly described out-of-plane approach ⁴; aligning one's sonographic window parallel (and immediately superficial) to the course of the extensor carpi radialis brevis (ECRB), which will appear as a fibrillar structue spanning across the near field, allows puncture between Lister's tubercle and the ECRB, following the needle tip dynamically to the targeted effusion. An in-plane approach may also be used ⁵.

Complications

• infection
• bleeding
• nerve injury