The Ajax Pain Clinic
Magdi Gaid MD ChB FRCPC
Kirit Patel MD FRCPC
Kevin Smith MD FRCPC
95 Bayly Street West, # 402
Ajax, ON L1S 7K8
T 905 427-3900
F 905 427-7090
Epidural Steroid Injections (ESIs)
Overview
Epidural steroid injection (ESI) is a non-surgical
treatment that can help relieve pain in the neck, arm, low
back and leg (sciatica) caused by irritation of the spinal
nerves. ESIs are performed to relieve pain caused by
spinal stenosis, spondylosis or disc herniation. The
epidural injection delivers a long-lasting steroid and often
an anesthetic agent to the irritated and inflamed spinal
nerve(s). Medicines are delivered to the nerve through
the epidural space - that is the area between the
protective covering of the spinal cord and backbones.
The effects of ESIs are usually temporary and vary.
Pain relief may last for 1 week or up to 1 year. The goal
is to reduce pain so that patients may resume their
normal activities and, in some cases, continue a physical
therapy program.
What is an epidural steroid injection?
This injection includes both a long-lasting steroid
cortisone called a corticosteroid (e.g. depomedrol,
triamcinolone) and an anesthetic (e.g. bupivicaine,
lidocaine). The drugs are delivered into the epidural
space of the spine, which is the area between the
protective covering (dura) of the spinal cord and
vertebrae (back bones). ESIs can relieve symptoms
caused by inflammation and pressure on the spinal
nerves. Corticosteroids can reduce inflammation and
can be effective when delivered directly into the site of
the painful part of the neck or back.
Who is a candidate for ESI?
Patients with pain in the neck, arm, low back or leg
(sciatica) may benefit from ESI. Specifically, those with
the following conditions:
 Spinal stenosis: a narrowing of the spinal canal
and nerve root canal that causes back and leg
pain.
 Spondylosis: a weakness or fracture between
the upper and lower facets of a vertebra. If the
damaged vertebra slips forward
(spondylolisthesis), it can compress the nerve
roots, causing pain.
 Herniated disc: the gel-like center of an
intervertebral disc ruptures and releases
inflammatory proteins. Pain results when the
proteins contact a nearby nerve causing
inflammation.
ESIs have proven helpful for some patients in the
treatment of the above painful inflammatory conditions.
ESIs can also help to determine whether surgery might
be beneficial for pain associated with a herniated disc.
When symptoms interfere with rehabilitative exercises,
epidurals can ease the pain enough so that patients can
continue their rehabilitation.
ESIs should not be performed on people who have an
infection or those with bleeding problems. Extra care
should be taken in performing ESIs on people with
pregnancy, diabetes, hypertension, heart disease or
renal failure due to the possibility of short-term
aggravation of these conditions. ESIs may not be
performed on patients whose pain is from a tumour or
infection, and if suspected, an MRI scan should be done
prior to the injection to rule out these conditions.
Who performs ESIs?
In Canada, the vast majority of ESIs are performed by
Anesthesiologists.
What happens before treatment?
If you are taking aspirin you may need to stop taking it 7
days before the ESI. Other blood thinners such as
Plavix and Ticlid need to be stopped for 14 days before
injection. Coumadin (warfarin) needs to be stopped 10
days before injection. Discuss any medications with one
of the Pain Clinic doctors.
Make arrangements to have someone drive you
home from your ESI appointment.
What happens during treatment?
The goal is to inject the medication as close to the pain
site as possible. The right type of injection for you
depends on your condition and which procedure will
likely produce the best results and the least discomfort
or side effects. The entire procedure usually takes less
than 15 minutes.
The injection is usually performed in the outpatient
Ambulatory Care Unit (ACU) on the ground floor of the
Ajax Hospital. You will be awake for the injection.
Sedatives to lessen anxiety may be available for
exceptional circumstances; this must be arranged at the
time of booking the injection and will lengthen your stay
in hospital. You will either be sitting or lying on your side
for the injection. Your blood pressure and pulse will be
taken before and after the procedure. After the initial
temporary burning sensation from local anesthetic
applied in the skin, the injection is usually not painful.
Some mild discomfort, often described as deep
pressure, may occur during injection of the medication.
Occasionally your leg pain may temporarily be
reproduced during the injection.
What happens after treatment?
Most patients may walk within 10 minutes after the
procedure. After being monitored for a short time, you
can usually leave the hospital. Although you may feel
better the same day, take it easy for 24 to 36 hours after
the injection to allow the anti-inflammatory benefits to
take effect. You may find your pain is aggravated for 1
or 2 days after the injection, followed by a gradual
improvement, especially in the leg pain if present. Most
patients can resume normal activities and/or participate
in their physical therapy program within a few days after
the ESI.
Localized soreness is usually relieved within 24 hours by
using ice, reducing strenuous activities and taking a mild
analgesic and/or anti-inflammatory such as ibuprofen.
Patients are advised to reduce work schedule and
activities for 48 hours following the procedure to help
healing.
Call the Ajax Pain Clinic if any of the following occur:
fever > 38.5 celsius, shortness of breath, bowel or
bladder incontinence, severe headache, increased pain
lasting over 1 week, increased weakness or numbness,
sign of infection at the needle site (red, warm, tender,
swollen, drainage). If you cannot contact us, see your
family doctor immediately, GO TO THE NEAREST
EMERGENCY ROOM or dial 911.
however, there are few risks associated with ESIs and
they tend to be rare. Risks may include:

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Infection. Minor infections occur in 1% to 2%
of all injections. Severe injections are rare,
occurring on 0.1% to 0.01% of injections.
Bleeding. Bleeding is a rare complication and
is more common for patients with underlying
bleeding disorders.
Nerve damage. While extremely rare, nerve
damage can occur from direct trauma from the
needle, or secondarily from infection or
bleeding. Arachnoiditis, or inflammation of the
lining if the dural sac, may rarely cause worse
pain.
Dural puncture (“wet tap”). A dural puncture
occurs in 0.5% of injections. It may cause a
post-dural puncture headache, also called a
spinal headache, that usually gets better within
a week. If this occurs, leave us a message at
the office, drink plenty of caffeinated fluids
(coffee, tea, colas) and use pain killers as
required. Although uncommon, if you are
unable to manage at home an epidural blood
patch may be necessary to alleviate the
headache.
What are the results?
About 50% of patients experience significant pain relief.
If you don’t notice any such benefit, discuss additional
injections with the doctor. You will be booked for 3
consecutive injections, each 3 to 6 weeks apart. The
need for each subsequent injection will be reassessed at
the time of the booked appointment. You will be given a
follow-up appointment for approximately 3 months after
the final injection to determine overall effectiveness of
the treatments and to plan the next steps. The benefits
of ESIs tend to be temporary. Some patients experience
pain relief for as little as 1 week and others for up to 1
year. Most importantly, patients may experience enough
relief to get moving again, resuming normal activities
and/or continuing a physical therapy program.
What are the side effects?
In addition to risks from the injection, there are also
potential risks and side effects from the medication
injected. These side effects tend to be uncommon and
temporary unless injections are repeated often for
several months. Patients who are being treated for
chronic conditions (e.g. heart disease, poorly controlled
diabetes, rheumatoid arthritis, or those who cannot
temporarily discontinue anti-clotting medications) should
consult their personal physician for a risk assessment.
Risks and side effects may include:
 High blood sugar
 High blood pressure
 Transient flushing
 A transient decrease in immunity
 Water retention, swelling and weight gain
 Rarely stomach ulcers, severe arthritis of the
hips (avascular necrosis), cataracts, increased
appetite
 Transient numbness and mild muscle weakness
usually resolve within 8 hours in the affected
extremity (similar to the facial numbness
experienced after dental work)
What are the risks?
As with all invasive medical procedures, there are
potential risks associated with ESIs. Generally,
Links for further information
www.spine-health.com
www.reddinganesthesia.com/ESB.htm
Avoid lifting objects more than 20 pounds or active
sports until advised otherwise. Swimming tends to help
you feel better and strengthens core muscle groups.