Patient Education 

 An unpleasant sensory and emotional experience associated with, or resembling that associated with actual or potential tissue damage.

The definition of “PAIN” by the International Association for the Study of Pain (IASP)

What is the role of interventional pain?

Although some pains can be treated with physiotherapy, chiropractics, medicines, or surgery, not all pain responds to these modalities and sometimes pain procedures need to be performed. Procedures (or interventions) are done for 1 of 2 reasons:

  1. To treat the site of pain (example: joint injections)
  2. To modify the nerve signal connected to the site of pain. This is called Radiofrequency Ablation (RFA) or rhizotomy and has been around in clinical use since 1973.

For example: if your back hurts because you have arthritis, one option would be to inject the arthritic joints to treat inflammation as a cause of your pain, while another is called Radiofrequency Ablation (RFA). RFA is a procedure during which small nerve endings are heated and melted down so that there is a loss of feeling to the painful area. This is a long-lasting and safe therapy used to decrease the volume or intensity of the signal going through the nerves that plug into painful arthritic joints (to unplug them), so they stop sending signals of pain from the arthritic joints to the brain. For example, if an Interventional Pain Specialist stops a nerve from firing, patients don’t have to feel their arthritic knee, shoulder, neck, or back pain, among other pains, and can live their lives more normally with improved function and quality of life. RFA will typically give a patient months of pain relief until the small nerve endings grow back and it can be repeated safely multiple times (sort of like a nerve branch haircut).

What Kinds of Pain Problems Can RFA Treat?
  • Herniated discs
  • Sciatica
  • Low back pain
  • Sacroiliac joint (SIJ) pain
  • Upper back pain
  • Neck pain
  • Rib pain
  • Chest wall pain (aka non-cardiac chest pain)
  • Abdominal wall pain
  • Sacral pain
  • Chronic headaches /Migraines
  • Whiplash injuries
  • Tailbone pain
  • Pinched Nerves
  • Spinal Stenosis
  • Compression Fractures
  • Shingles Pain
  • Large joint arthritic pain (knees, hips, shoulders)
  • Complex Regional Pain Syndrome (CRPS) / Reflex Sympathetic Dystrophy (RSD)
  • Ischemic (Vascular) Pain (aka vascular claudication)
Where are these procedures done, and are they covered by OHIP?

Yes. All procedures are covered by OHIP. Only a few clinics/hospitals are approved to perform these procedures, with Bloor Pain Specialists being one of them. Check with your GP, neurologist, chronic pain doctor, or another specialist. You will need a referral from your Family Doctor or specialist before scheduling an appointment. Please bring all MRI/CT/X-ray/EMG reports when you go for your consultation.

What is X-Ray or Ultrasound-Guidance (aka Image-Guidance) and Why is it Often Considered a Standard of Care?

Your doctor can use an x-ray (aka fluoroscopy) or ultrasound during any non-superficial procedure to visualize or watch his or her needle move between tissues accurately to the correct anatomical location (joint, nerve, disc, tendon, bursa). That’s what x-ray guidance or ultrasound guidance refers to.

Quite simply, a low dose of X-ray or ultrasound let’s the doctor see and, if you don’t look (with x-ray or ultrasound) where the needle is going, how do you know where it is going? It has been known for decades that needles deviate from their intended path inside the body and that without image guidance, their path cannot be steered, changed, or guided accurately to the anatomically correct tissue being targeted. This has been studied time and again, with multiple studies showing more accurate delivery of medication or injection with the use of technology to guide and visualize a needle’s path. Some hip injection studies, for example, show a 23% to 35% failure rate of orthopedic surgeons for injecting the hip when done blindly by touch without image-guidance (also known as the older “landmark” technique), which increased to a 42% failure rate in orthopedic residents.

Resources regarding image-guidance advocating for its use as a Standard-of-Care in Interventional Pain Management:

American Society of Anesthesiologists’ Practice Guideline for Chronic Pain Management:

Spine Intervention Society:

USRA: (this is a Canadian Society based out of Toronto Western Hospital at part of UHN, the University of Toronto’s University Health Network)

Ontario Association of Radiologists:



So why is this image guidance discussion so important? Because image-guidance is often considered a standard-of-care that Specialists throughout Ontario practice with, but not all physicians are trained or practice in this manner, which has been publicly discussed in media on multiple occasions. Patients can ask their physicians about their training and request a referral to Bloor Pain Specialists if they feel a standard-of-care has not been met elsewhere.

What are epidural steroid injections (ESIs)?

The epidural space is a location that surrounds the nerves of the spine. “Epi” means outside and “dura” is the name of the membrane that holds the spinal fluid and the nerves. Hence, the epidural space is by definition the space outside the nerves of the spine.

The epidural space can have a number of different things injected or inserted into it. In labor, women often get an epidural catheter (tube) placed, but this cannot be done with x-ray guidance because x-rays can be bad for developing fetuses and babies.

In the outpatient setting, for the management of pain, corticosteroids are sometimes put into the epidural space with x-ray guidance. This x-ray guidance allows for more precise placement of the needle and magnification of the needle, which allows for a smaller needle to be used.

These injected corticosteroids are medications that act as antidotes to inflammation, very potently improving any inflammation around a nerve root or herniated disc for conditions like sciatica.

Unless the patient is pregnant, these procedures should always be performed with a mobile C-Arm X-ray machine (fluoroscopy) in a specially-built procedure suite in a clinic, or an operating room, as a standard of care, to watch the needle go accurately to the correct layer of the spine. The x-ray is used to take pictures as the needle is moved into the correct position to target each nerve root or herniated disc. Bloor Pain Specialists has 4 of these procedure suites and C-Arm machines.

What kind of doctor can perform epidural steroid injections?

Although several specialties perform epidural steroid injections, the most experienced specialists are anesthesiologists. Typically, these will undergo additional sub-specialty training called a “fellowship” or another form of additional education to sub-specialize in doing this form of procedure. In each province, the regulatory body will inspect the physician’s credentials prior to approving the physician to perform these procedures in his or her province. In Ontario, the College of Physicians and Surgeons of Ontario (CPSO) would be the organization to make that decision for each individual case.

What Kinds of Pain Problems Can Epidural Steroid Injections Treat?
  • Herniated discs
  • Sciatica
  • Low back pain
  • Upper back pain
  • Neck pain
  • Arm Pain
  • Rib or chest wall pain (aka non-cardiac chest pain)
  • Abdominal Wall Pain
  • Sacral/Tailbone pain
  • Pinched Nerves
  • Spinal Stenosis
  • Shingles Pain
  • Surgical planning (typically referred by a surgeon or Rapid Access Clinic for diagnostic Selective Nerve Root Blocks (SNRBs))
Where are these procedures done, and are they covered by OHIP?

Yes. All procedures are covered by OHIP. Only a few clinics/hospitals are approved to perform these procedures, with Bloor Pain Specialists being one of them. Check with your GP, neurologist, chronic pain doctor, or other specialists. You will need a referral from your Family Doctor or specialist before scheduling an appointment. Please bring all MRI/CT/X-ray/EMG reports when you go for your consultation.

What is a Nerve Block?

A nerve block is simple. Nerves conduct electrical impulses to send all kinds of sensory signals (hot, cold, itchy, pressure, dry, wet, etc), including signals of pain. Local anesthetics numb nerves and prevent them from sending their signals.


Hence, a nerve block is quite simply an injection of a local anesthetic around a nerve to make it numb. This is not expected to last very long because local anesthetics do not last very long. That’s why nerve blocks are intended to primarily be used for diagnostic purposes (to figure out which nerve is causing/transmitting the pain by numbing it up and asking the patient if they feel better) and if the patient’s response to the nerve block, this is usually followed by radiofrequency ablation (RFA) of the nerve(s).


Joint Injections: 4 choices of injectate, pros, and cons


  1. Local anesthetic: This is done for diagnostic reasons only. For example, a back surgeon might send patients to Bloor Pain Specialists if they have herniated discs and hip pain. Sometimes hip pain comes from the hip, but sometimes it comes from the herniated discs, and the MRI or CT scan cannot feel for the patient so the scan cannot say which structure is really causing the pain. Hence, surgeons will refer patients for an injection of a local anesthetic to “diagnose” the source of the pain. This injection of local anesthetic freezes locally, meaning that if the hip is injected and frozen, but the patient gets up and he or she still has pain, then his or her pain is diagnosed as coming from the herniated discs and that patient knows he or she should not have hip surgery. If the pain disappears for a few hours with the injection of local anesthetic as the hip is frozen, then the diagnosis is made and this patient should have hip surgery.


  1. Corticosteroids (aka “cortison”): These are anti-inflammatory medications that can reduce swelling and inflammation to improve function in a tendon, bursa, disc, or joint, but they have some negative side effects for bone density and connective tissue. In 2017, the Journal of the American Medical Association published a major article examining cartilage volume loss with repeat injections into patients’ knees and found significant decay of cartilage with an injection of corticosteroids, but no difference in pain when compared to saline.


  1. Hyaluronic Acid: This is a substance used to supplement joint fluid to cushion the two boney sides of any joint from touching each other and causing pain. Although there is ample evidence of its efficacy, this is not an OHIP covered service per the Ministry of Health and Long-Term Care.


  1. Platelet Rich Plasma (PRP) and Stem Cell Injections: This is an evolving field and there are differences between PRP and stem cell injections. These are also not OHIP covered services.


Platelet Rich Plasma (PRP) injections have several steps. First, the patient is screened for appropriateness, with bloodwork/lab testing if needed. If appropriate, the patient presents on the day of the procedure, has blood drawn and prepared for the separation of the blood layers in a centrifuge and isolation of the PRP from the rest of the blood. Then, after centrifugation and separation, the patient’s own PRP is re-injected into a different part of the body (i.e. in a joint or disc, around a ligament or tendon sheath). There are many nuances to PRP technology and techniques and the medical literature is still evolving. It is safe, but more efficacy data are still being studied, so firm conclusions should not be drawn as of yet.


Stem Cell Injections are not advisable per Health Canada.

Are there other ways to treat my pain, other than injections?