Nerve Blocks: What is it?
Under fluoroscopy or ultrasound, local anaesthetic, with a corticosteroid when appropriate, is placed around the nerve or nerve root carrying the pain. A diagnostic block shows whether the pain comes from that nerve; a therapeutic block reduces inflammation and pain.
Who it’s for
- Epidural (interlaminar, transforaminal, caudal)
- Facet joint / medial branch block
- Selective nerve root block
- Occipital nerve block
- Genicular (knee) nerve block
- Suprascapular (shoulder) block
- Stellate ganglion block
Before the procedure
Bring MRI or CT scans from the past year (disc and report).
Always tell us if you take them. Your doctor decides whether to pause them; do not stop on your own.
If sedation is planned, do not eat for the time you are told.
Come with someone who can take you home; do not drive.
Wear loose clothes that give easy access to the treatment area.
Tell us in advance about possible pregnancy, diabetes, allergies or a pacemaker.
How it’s done
- 1Target
The nerve to block is chosen from the exam and MRI.
- 2Guidance
The needle is guided to the target by fluoroscopy or ultrasound.
- 3Confirmation
Contrast confirms the medication spreads to the right place.
- 4Injection
Medication is given; you go home after a short observation.
After the procedure
First hours
Temporary numbness from the local anaesthetic is common.
Onset
The steroid effect usually starts within 2–7 days.
Pain diary
After a diagnostic block you note how your pain changes in the first hours.
Next step
If the diagnostic block is positive, RF may be planned for longer relief.
Risks and side effects
Like any medical procedure, this treatment has possible side effects. Most are mild and temporary; you receive detailed information and give written consent beforehand.
Pain at the injection site, numbness for a few hours, or brief weakness in the arm or leg.
Facial flushing, raised blood sugar for a few days, or disturbed sleep.
Infection, bleeding, headache from a dural puncture, or an allergic reaction.
Questions
How long does it last?
It varies by patient and block, from days to several months. Diagnostic blocks are short-acting; their purpose is to identify the source.
Is the steroid harmful?
A low dose is given to one area. If you have diabetes you will be asked to monitor your blood sugar for a few days.
Information on this site is for general guidance and does not replace a medical examination.