What is a Transforaminal Epidural Steroid Injection?

A Transforminal Epidural Steroid Injection (TFESI) is a targeted treatment used to relieve pain caused by inflammation or irritation of spinal nerves. The procedure involves delivering a combination of steroid (anti-inflammatory) and local anaesthetic precisely into the area where the nerve exits the spine, known as the neural foramen.
This injection can help reduce nerve swelling, relieve pain, and improve mobility, especially
in conditions such as:

  • Herniated ("slipped") discs
  • Acute Sciatica
  • Spinal stenosis
  • Degenerative disc disease
  • Nerve root irritation following injury or surgery

How Does it Work?

The steroid medication helps to decrease inflammation and swelling around the affected nerve root. The local anaesthetic provides temporary pain relief and helps confirm the source of pain.
By calming the irritated nerve, symptoms such as leg pain, numbness, or weakness often improve.

What Happens During the Procedure?

  • Positioning: You will lie on an X-ray table, usually on your front.
  • Cleaning and Numbing: The skin over your back will be cleaned with antiseptic, and a small amount of local anaesthetic will numb the area.
  • Guidance: Using live X-ray (fluoroscopy), the doctor will carefully guide a fine needle into the foramen near the affected nerve.
  • Injection: A mixture of steroid and local anaesthetic is slowly injected.
  • Monitoring: You will be observed briefly after the procedure to ensure you are well enough to go home.

The whole process typically takes about 20–30 minutes.

What Should I Expect After the Injection?

  • You may feel some numbness or heaviness in the leg for a few hours — this is temporary.
  • Pain relief may begin within a few days but can take up to two weeks.
  • Some people experience a brief increase in pain before improvement occurs.


Activity: You should rest for the remainder of the day and gradually resume normal activities as tolerated.
Follow-up: A review appointment may be arranged to assess your response to the injection.

Benefits

  • Targeted pain relief
  • Improvement in nerve-related symptoms (e.g., leg pain, numbness)
  • Helps reduce the need for stronger medications
  • May delay or avoid the need for surgery

Risks and Side Effects

While complications are rare, they can include:

  • Temporary increase in pain
  • Infection at the injection site
  • Bleeding or bruising
  • Nerve irritation
  • Allergic reaction to the medications
  • Very rarely, nerve injury or paralysis (extremely rare when performed by an experienced doctor under imaging guidance)

Steroid-related effects (usually mild and temporary):

  • Flushing of the face
  • Temporary rise in blood sugar (especially in diabetic patients)
  • Sleep disturbance
  • Mood changes

Important Information

Before the procedure:

  • Inform us if you are on blood thinners (e.g., warfarin, clopidogrel, apixaban) — you may need to stop them temporarily.

  • Inform us about any allergies or infections.

  • Continue taking your usual medications unless advised otherwise.

On the day:

  • Arrange for someone to drive you home after the procedure.
  • Avoid heavy lifting or strenuous activities for 24 hours.

When to Seek Helps

Contact your healthcare provider if you experience:

  • Severe or increasing pain
  • Signs of infection (fever, redness, swelling at the injection site)
  • New weakness or numbness in the legs
  • Difficulty passing urine