Name of Procedure
- TFESI – Lumbar or thoracic transforaminal (TF) epidural steroid injection (ESI) (diagnostic or therapeutic)
- Selective nerve root block (SNRB)
The Quick Guide
To access and then administer medication (such as local anesthetic or steroid) to the epidural space via a transforaminal approach to target specific nerve roots.
Usually to treat degenerative disc disease or neural foraminal stenosis that is causing radicular symptoms into the torso or legs.
See our disposables/equipment article for “core” supplies that are common to all procedures. Highlights below:
- Core Equipment
- c-arm, c-arm compatible bed
- Core Disposables
- Procedure tray. As outlined in the above link, core supplies include a pointer, syringes for subcutaneous local, syringe for injectate, drape.
- Core Skills
Special items and suggested setup for this procedure (see quick guide video above for example tray prep):
- 22g x 3.5″ (or 5″) quincke needle
- 3cc 0.125% bupivicaine with steroid in 3cc syringe (about 1.5cc injectate per nerve root) (dexamethasone is low particulate and usually a good choice)
- 3cc contrast in 3cc syringe
- 5cc 1% lidocaine in 5cc syringe with 25g x 1.5″ hypodermic needle for subcutaneous local anesthesia
Landmarks and Patient Positioning
Position the patient in a basic prone position so that the bottom of the c-arm can go under the table below the area of the spine that is being treated.
- Get a basic scotty dog view of the target level (An AP view can also work).
- Line up and anesthetize an entry point about 2cm lateral and 2cm inferior to the infero-lateral tip of the transverse process.
- This gives you a trajectory that aims superior/medial/posterior, which helps get into the transforaminal space nicely.
- Insert a bent quincke needle targeting a landing at the inferior border of the transverse process, just lateral to where it joins the pedicle.
- From here, aim inferior and medial, and “walk” the needle off the bone.
- As soon as it walks off you should be medial and posterior enough to be in the transforaminal space.
- Sometimes it will need to be advanced slightly, but be careful to advance in very slight increments to avoid a paresthesia.
- Inject a small amount of contrast to confirm spread:
- Note the spread rounded under the pedicle, outlining the nerve root. This is typical spread but sometimes it doesn’t outline perfectly and instead you’ll just see medial spread over a wide area like with an interlaminar injection
- Injection under live fluoro or use of digital subtraction can help to make sure that you don’t see contrast uptake
- Inject the desired injectate based on the specific procedure (ie, local anesthetic only, or steroid, or both).
- A combination of experience, patient size and trajectory help you to determine depth. With the approaches mentioned above you usually don’t need a lateral to determine depth.
- While several steering techniques can usually be used, a sharp needle bend is useful here:
- As noted above, after contacting the TP initially, you’ll walk off and under the TP to get into the transforaminal space.
- This is often a short travel distance and so you want the needle to be easily steerable and to steer a lot over a short distance.
With the above technique you could pass under the transverse process and might hit the vertebral body. Always watch for cues that don’t look right and check other views to confirm.