Skip to content banner

Arthrocentesis Of The Wrist Joint


Morgan Potter, MD
Emergency Medicine Resident
Icahn School of Medicine at Mount Sinai

Amie Kim, MD
Associate Professor – Emergency Medicine
Associate Professor – Physical Medicine & Rehabilitation
Associate Professor – Department of Medical Education
Icahn School of Medicine at Mount Sinai
Mount Sinai Beth Israel


  • Radiocarpal arthrocentesis should be considered in the next step evaluation of wrist effusion. 
  • Diagnostic and therapeutic aspiration and medication delivery can be concomitantly performed. 
  • Radiocarpal joint space can be approached from two common entry points at the radiolunate joint –  between EPL and EDC or between EDC and EDM tendons. 
  • One should be familiar with the technique at both entry points and prepared for long and short axis approaches.
Basic anatomy and positioning of wrist arthrocentesis. Note the ulnar deviation and traction.[1]Image courtesy of, “Wrist Arthrocentesis”
Ultrasound guided wrist arthrocentesis in long axis.
Ultrasound guided wrist arthrocentesis in short axis.


  • Radiocarpal arthrocentesis should be highly considered in patients presenting with unexplained wrist effusion with synovial fluid analysis being the gold standard to diagnose septic arthritis and gout.
  • Small volume diagnostic arthrocentesis or therapeutic large volume drainage are common indications.
  • Under a single procedure, the same needle can also deliver therapeutic medications into the joint space.
  • Ultrasound visualization is often incorporated for improved safety and precision[2]Balint PV, Kane D, Hunter J, McInnes IB, Field M, Sturrock RD. Ultrasound guided versus conventional joint and soft tissue fluid aspiration in rheumatology practice: a pilot study. J Rheumatol. … Continue reading[3]Reichman EF. Arthrocentesis. In: Reichman’s Emergency Medicine Procedures, 3rd Edition. 3rd ed. McGraw-Hill Education/Medical; 2018.


  • The wrist joint is composed of the distal radius, ulnar and proximal carpal role.
    • The proximal carpal bones include the scaphoid, lunate and triquetrum which articulate with the radius and ulna
    • The radius and ulna form the distal radioulnar joint, which is a separate discrete joint.
    • The ulna is technically separated from the carpal role by an articular disc which prevents it from directly articulating with the proximal carpus
  • The joint is composed of a complex series of radiocarpal and collateral ligaments and the neurovascular supply comes from branches of the radial and ulnar arteries
  • The flexor tendons cross within the carpal tunnel (not pictured), while the dorsal extensor tendons cross in a series of discrete extensor compartments (see below).
llustrated surface anatomy of the dorsal wrist. (1) The first dorsal compartment (abductor pollicis longus and extensor pollicis brevis). (2) The second dorsal compartment (the extensor carpi radialis longus [ECRL] and the extensor carpi radialis brevis [ECRB]) and the location of intersection syndrome. (3) The third dorsal compartment (extensor pollicis longus). The fourth and fifth compartments have been omitted for clarity. (4) The sixth dorsal compartment (extensor carpi ulnaris). (5) Lunate, (6) triquetrum. (7) Insertion of the ECRL and ECRB and the location of carpal boss. (*) Lister’s tubercle. (#) Scapholunate interval.[4]Image courtesy of, “Hand and Wrist Diagnosis and Decision Making”
Bony anatomy of the wrist including the radiocarpal joint.[5]Image courtesy of, “Anatomy 101: Wrist Joints”
Dorsal compartments of the wrist (click to enlarge)[6]Case courtesy of Assoc Prof Craig Hacking,, rID: 47014

Ultrasound Evaluation

  • General
    • The patient is seated or supine
    • A linear transducer is used
    • Identify relevant landmarks on the dorsal wrist.
    • Familiarize yourself with the patient’s surface anatomy and sono-anatomy before preparing your sterile field.
    • In the presence of a large wrist effusion, the dorsal recess will be distended with an anechoic fluid collection superficial to the carpal bone.
Ultrasound example of wrist effusion (yellow arrow).[7]Jacobson JA. Wrist and Hand Ultrasound. In: Fundamentals of Musculoskeletal Ultrasound. Elsevier; 2018.
Wrist ultrasound demonstrating joint effusion in long axis.
Wrist ultrasound demonstrating joint effusion in short axis.
  • Sonographic landmarks
    • Anatomic snuff box
      • Radial border: extensor pollicis brevis (EPB)
      • Ulnar border: extensor pollicis longus (EPL)
      • Note: tendon surface anatomy is better palpated with active thumb abduction and extension
    • Lister’s tubercle
      • Palpate EPL proximally to land on the tubercle of the distal radius
    • Scaphoid
    • Lunate
      • Ovoid structure palpable between proximal edge of 3rd metacarpal base and distal and immediately ulnar to Lister’s tubercle
  • Radiocarpal joint space (short axis)
    • Place the probe over Lister’s tubercle. Identify the bony protrusion in the center of your screen
    • Radial to Lister’s tubercle, identify the second extensor compartment containing extensor carpi radialis brevis (ECRB), extensor carpi radialis longus (ECRL)
    • Ulnar to Lister’s tubercle, identify EPL. Ulnar to EPL, identify extensor digitorum
    • Sweep distally and identify EPL begin to transition radially towards the thumb and the space between the third and fourth extensor compartments widens. As you pass through the hypoechoic radiocarpal joint space, the hyperechoic radius drops off the screen and the scaphoid comes into view.
    • Slide the probe ulnarly to identify the lunate ulnar to the scaphoid. Sweep across the scapholunate intercarpal joint. In this view you can also view the scapholunate ligament.
    • Return the probe proximally toward the radius across the radiolunate joint space.
Listers tubercle in short axis (arrows). The radius, ulna and 2nd, 3rd and 4th dorsal extensor compartments are also marked.[8]Case courtesy of Dr Maulik S Patel,, rID: 35116
Short axis view of the wrist showing the radiolunate joint space. Note radioligament is marked (arrows).[9]Gitto S, Draghi F. Normal sonographic anatomy of the wrist with emphasis on assessment of tendons, nerves, and ligaments. J Ultrasound Med. 2016;35(5):1081-1094.
  • Radiocarpal joint space (long axis)
    • Place the probe in long axis over Lister’s tubercle.
    • Slide the probe distally until the hyperechoic contours of the radius are interrupted by the hypoechoic dorsal recesses of the radiocarpal joint. Continue sliding the probe distally until the hyperechoic scaphoid bone enters into view.
    • Align the joint space at the center of the screen, with the bony edges of the radius and scaphoid on opposite sides of the screen.
    • Translate the probe ulnarly until the lunate enters view. Your probe will lie ulnar to EPL and radial to extensor digitorum.
      • This is the most common location for aspiration (entry point 1)[10]Jacobson JA. Wrist and Hand Ultrasound. In: Fundamentals of Musculoskeletal Ultrasound. Elsevier; 2018.[11]Reichman EF. Arthrocentesis. In: Reichman’s Emergency Medicine Procedures, 3rd Edition. 3rd ed. McGraw-Hill Education/Medical; 2018.[12]Sanford SO. Arthrocentesis. In: Roberts and Hedges’ Clinical Procedures in Emergency Medicine and Acute Care. 7th ed. Elsevier – Health Sciences Division; 2018.
    • Continue translating your probe ulnarly, passing over the longitudinal 4 tendons of extensor digitorum. Extensor digiti minimi will come into view.
      • From here, return the probe radially 1-2 mm. In line with the base of the 4th metacarpal, the radiolunate joint space between the EDC and EDM tendons is Entry Point 2
      • This is an alternative approach for aspiration (entry point 2)[13]Sanford SO. Arthrocentesis. In: Roberts and Hedges’ Clinical Procedures in Emergency Medicine and Acute Care. 7th ed. Elsevier – Health Sciences Division; 2018.
Lister’s tubercle in long axis.
Radioscaphoid joint space ultrasound long axis
Transducer and needle position for arthrocentesis in short axis.
Wrist Arthrocentesis Long Axis Position
Transducer and needle position for arthrocentesis in long axis.


  • Landmark vs. Ultrasound Guided Approach
    • Performing wrist arthrocentesis under ultrasound guidance is the preferred method relative to landmark-guided technique or ultrasound mapping followed by blind needle insertion.
    • Location of the distal needle tip is confirmed throughout the procedure, while both the target and the structures to be avoided (i.e. vessels, nerves, tendons) remain visualized.[14]Reichman EF. Arthrocentesis. In: Reichman’s Emergency Medicine Procedures, 3rd Edition. 3rd ed. McGraw-Hill Education/Medical; 2018.
    • Higher accuracy and precision, decreased time to target, and lower complication rates have been demonstrated with ultrasound guidance relative to blind technique.[15]Gilliland CA, Salazar LD, Borchers JR. Ultrasound versus anatomic guidance for intra-articular and periarticular injection: A systematic review. Phys Sportsmed. 2011;39(3):121-131.[16]Gordon RD, LaRavia L, Eric Z, Lyon M. A comparison of ultrasound-guided to landmark-guided arthrocentesis of ankle, elbow, and wrist. Ann Emerg Med. 2013;62(4):S34.
  • Materials
    • 18 gauge draw needle
    • 1.0 – 1.5 inch, 25 gauge needle for aspiration and injection
    • Note: small joint but may require larger gauge for aspiration
    • 3 – 5 cc syringe
    • Local anesthetic
    • Sterile equipment (gauze, skin prep, gloves, probe cover, etc)
  • General
    • There are multiple approaches including long axis and short axis, and in-plane and out-of-plane
    • The authors recommend long axis, in-plane technique which is described below
    • This allows avoidance and transection of extensor tendons and radial radial nerve
    • Can be performed without assistance, although an assistant is recommended
    • Procedure should be done with strict sterile technique
    • Arrange supplies for easy access and minimal movement once starting the procedure.
  • Position patient
    • The patient is supine or seated
    • Rest the patient’s wrist on an adjustable height stand.
    • Place the volar aspect of the wrist onto a towel roll to position the wrist into passive flexion in approximately 20-30 degrees
    • Have your assistant apply axial traction, ulnar deviation to the wrist to maximally open joint space.
Demonstration of patient positioning[17]Image courtesy of, “Wrist Arthrocentesis”
  • Procedure
    • Identify the distal radius, the radio-lunate joint space, and the lunate in view.
      • Confirm your position at one of two entry points without overlying tendons
    • Anesthetic
      • Inject a superficial wheel of the anesthetic over the intended injection site with a 25-30 gauge needle.
      • If using vapor coolant, an assistant can anesthetize the injection site before needle insertion.
    • Position the needle at the marked position.
      • Maintain visualization of needle during entire procedure
    • Insert the needle several millimeters distal to the probe edge and adjust the angle of insertion.
      • Alternatively, lift the probe off the skin, penetrate the skin several millimeters, and then return the probe to position
      • Consider creating a ‘step off’ with ultrasound gel
    • As the needle is advanced, the shaft and distal tip should remain visible as a hyperechoic structure.
      • To improve needle image, slowly tilt the probe back and forth (about 1mm in each direction), maintain firm contact with the skin, and orient the probe face parallel with the needle shaft.
    • Optional: once the needle penetrates the joint space, turn the probe 90° to confirm location in both planes.
    • Aspiration is easier performed with an assistant to exchange syringes as you continue to operate the probe and needle.


  • Sterile gel ‘stand off’ or ‘step off’
    • Also known as an oblique stand-off technique. 
    • Lift the probe off the skin, applying ample sterile gel (at least 1-2cm deep). 
    • Gently rest the probe over the gel, being careful not to displace the gel around the probe. 
    • This allows needle identification within the gel, before puncturing the skin, and more space for needle adjustment while maintaining target visualization.[18]acobson JA. Interventional Techniques. In: Fundamentals of Musculoskeletal Ultrasound. Elsevier; 2018.[19]Sanford SO. Arthrocentesis. In: Roberts and Hedges’ Clinical Procedures in Emergency Medicine and Acute Care. 7th ed. Elsevier – Health Sciences Division; 2018.
Demonstration of an ultrasound ‘step off’ or ‘stand off’.
  • If the needle tip is within the joint capsule, injectate should flow freely with minimal resistance and joint space expansion should be seen under ultrasound.[20]De Maeseneer M, Marcelis S, Jager T, Girard C, Gest T, Jamadar D. Spectrum of normal and pathologic findings in the region of the first extensor compartment of the wrist: sonographic findings and … Continue reading[21]Lohman M, Vasenius J, Nieminen O. Ultrasound guidance for puncture and injection in the radiocarpal joint. Acta Radiol. 2007;48(7):744-747.
    • If high resistance is encountered, confirm the needle tip is in the desired location. 
    • Retract the needle from the joint space, re-orient and attempt again. 
  • Short axis approach
    • An in-plane or out-of-plane approach with the US probe in short axis position has not been formally described for the radiocarpal joint
    • It could be considered as a possible backup if the sagittal approach proves difficult.  

Intercarpal Joint Arthrocentesis

  • Patient position
    • Supine or seated
    • Hand pronated, wrist in slight flexion (20-50°) and ulnar deviation.[22]Reichman EF. Arthrocentesis. In: Reichman’s Emergency Medicine Procedures, 3rd Edition. 3rd ed. McGraw-Hill Education/Medical; 2018.
  • Setup
    • Injection site distal to lunate and proximal to 3rd metacarpal
    • US probe placed over indentation distal to lunate bone
  • Procedure
    • Identify optimal view should show a hypoechoic joint space
    • Insert a 22-gauge needle perpendicular to the skin, advance 0.5 to 1.0 cm
  • Note: all carpal joints are connected
(A) Ultrasound long-axis scan of a normal wrist joint using a high frequency linear transducer. Intercarpal recess marked (asterisk), the IV extensor tendon compartment. (B) Short axis ultrasound scan of a normal right wrist. White arrows show the two most common needle paths between extensor tendons compartments.[23]Lazarou I, Kelly SG, Meric de Bellefon L. Ultrasound-guided synovial biopsies of wrists, metacarpophalangeal, metatarsophalangeal, interphalangeal joints, and tendon sheaths. Front Med (Lausanne). … Continue reading

Pearls & Pitfalls

  • Position the patient to maximally open the joint space. The operator, the orientation of the screen, and the line of needle entry and advancement should all be aligned on the same axis.
  • Do not advance the needle against resistance, as it may be synovium or articular cartilage.
  • Do not move the needle once it begins draining synovial fluid
  • If the needle needs to be repositioned, withdraw almost to the skin surface before adjusting angle of entry.
  • Align the bevel side of the needle parallel with neighboring tendons to support “splitting” tendon fibers instead of transection
  • Do not confuse a ganglion cyst of the wrist for a joint effusion