What is the recommended technique for a mid radiocarpal (wrist) joint injection?

Mid Radiocarpal Joint Injection Technique

For mid radiocarpal joint injection, use ultrasound or fluoroscopic guidance with a dorsal approach, positioning the needle between the radius and scaphoid, as imaging guidance ensures 100% success rates compared to only 72% with palpation-guided techniques. 1

Pre-Procedure Preparation

• Obtain informed consent explaining the procedure nature, potential benefits, side effects, and post-injection care 2
• Position the patient on an adjustable examination table in a comfortable position with the wrist accessible 2
• Ensure resuscitation equipment is readily available, as vasovagal reactions occur in approximately 2.6% of joint injections 2
• Maintain strict aseptic technique using surgical gloves, skin preparation with alcohol or chlorhexidine, and consider changing needles between drawing medication and injecting 2, 3

Imaging Guidance Selection

Ultrasound guidance is the preferred method for radiocarpal injection as it provides:

• 100% success rate versus 72% with palpation 1
• Shortest procedure time (6.5 ± 1.6 minutes) compared to fluoroscopy (12.5 ± 1.9 minutes) or palpation (8 minutes) 1
• Least painful technique at all post-injection time points 1
• No radiation exposure 1
• Fewer puncture attempts (1.1 ± 0.24) compared to palpation (1.6 ± 0.8) 1

Fluoroscopy guidance is an acceptable alternative with 100% success rate, though more time-consuming and involving radiation exposure 1

Injection Technique

Needle Positioning

• Use a dorsal approach to the radiocarpal joint 4, 1
• Position the needle tip at the medial part of the proximal scaphoid, directed obliquely at a 45-degree angle to reach the radiocarpal joint space 4
• This technique allows access to both midcarpal and radiocarpal compartments from a single puncture site if needed 4

Equipment Selection

• Use a 20-24 gauge needle for radiocarpal injection 5
• Attach to a dry syringe initially for joint entry confirmation 5
• Aspirate a few drops of synovial fluid to confirm intra-articular placement before injecting 5

Medication and Volume

• Inject 20-80 mg of corticosteroid (e.g., methylprednisolone acetate) for large joints like the wrist 5
• Limit injection volume to avoid extravasation, as palpation-guided techniques show 56% extravasation rates 1
• Consider adding local anesthetic (e.g., lidocaine) to reduce procedural discomfort 2, 3

Post-Injection Care

• Move the joint gently a few times after injection to aid mixing of synovial fluid and medication 5
• Apply a small sterile dressing to the injection site 5
• Inform patients about potential side effects including injection-site soreness (most common), pain exacerbations, facial flushing/sweating, and vasovagal reactions 2, 3
• Monitor diabetic patients for transient hyperglycemia, particularly those with suboptimal glucose control 3

Common Pitfalls to Avoid

• Avoid palpation-guided injections as they have significantly lower success rates (72%), require more attempts, and result in frequent extravasation (56%) 1
• Do not inject into surrounding tissue rather than the joint space, as this is the most common cause of treatment failure 5
• Avoid injecting at least 3 months before planned joint replacement surgery 3
• Do not discontinue anticoagulation, as bleeding risk is low with joint injections 2, 3

Re-injection Considerations

• Repeat injections may be appropriate if there was 75% or more relief from initial injection, or at least 50% relief lasting 2 months 2, 3
• Interval between injections typically ranges from 1-5 weeks depending on degree of relief obtained 5