Sternoclavicular joint injection (technique)
Sternoclavicular joint (SCJ) injections under image guidance ensure precise delivery of an injectate into the joint and importantly that needle depth is under direct visualization.
Indications
- pain
- arthropathy, e.g. osteoarthritis
- diagnostic injection
Contra-indications
Absolute
- anaphylaxis to contrast/injectates
- active local/systemic infection
Relative
- bleeding diathesis
- recent musculoskeletal steroid injection
- unable to remain still for the procedure
- young age
Procedure
The general principles of SCJ injections are to:
- cannulate the joint
- confirm an intra-articular position with imaging
- administer intra-articular injectate, usually a corticosteroid and a small amount of longer-acting local anesthetic, e.g. ropivacaine; he SCJ is a small joint, therefore, the injectate volume should reflect this
Pre-procedural evaluation
Relevant imaging should be reviewed, and the details of the patient confirmed. The patient should have an opportunity to discuss the risks and benefits and consent obtained. Focused ultrasound is usually performed.
Risks include:
- infection
- bleeding
- allergy
- focal fat necrosis/ skin discolouration at the injection site
- steroid flare
Equipment
- ultrasound machine, sterile probe cover and a skin marker
- skin cleaning product
- sterile drape
- sterile field and tray for sharps
- syringe selection i.e. 5 mL and 3 mL
- larger bore drawing up needle
- needle to administer local anesthetic i.e. 30 or 25-gauge needle
- needle to cannulate the joint i.e. 25 or 27-gauge needle
- injectants i.e. local anesthetics, iodinated contrast, corticosteroid preparation
- sterile gauze
- adhesive dressing
Syringe selection
Using a Luer lock syringe for the injectate will mean the needle and syringe will not disconnect as the joint is often under pressure.
A suggested syringe and injectate selection for an ultrasound-guided SCJ anesthetic arthrogram injection:
- 5 mL syringe: 3 mL of local anesthetic, e.g. 1% lidocaine
- 3 mL syringe (Luer lock), e.g. 40 mg triamcinolone acetonide (40 mg/1 mL) and 1 mL 0.5% ropivacaine
Needle selection
Smaller gauge needles can be less painful but are less stiff and can bend when trying to cannulate a joint.
- SCJ: 25 or 27-gauge needles
Technique
Ultrasound
- check for allergies and if on blood thinners
- consent
- optimize patient positioning by laying them supine on the bed at 45 degrees for anterior access
- identify the joint in a transverse plane; perpendicular to the clavicle, optimize imaging and mark skin entry point
- clean skin and draw up appropriate medications
- consider local anesthesia along the proposed needle path
- under careful ultrasound guidance using anterior access, insert the needle in-plane with the probe into the SCJ, taking extreme care not to insert the needle too deep by keeping the tip in constant view
- administer arthrogram injectate under direct visualization
- remove the needle and apply dressing/ band-aid as required
Complications
Steroid flare is a relatively common side effect which will settle after 1 -2 days. The most serious complication is an infection causing septic arthritis. Steroid containing injections should be postponed if there are signs and/or symptoms of local and/ or systemic infection. Possible fat necrosis causing skin dimpling and skin discolouration can occur due to steroid leaking into the surrounding soft tissues, and this should be included in the consent, for this procedure especially in this visible area .