Trigger point injections

You have been referred to the hospital for trigger or tender point injections for your chronic pain. This leaflet will explain:

• what a trigger point injection is

• what happens during the procedure

• what the possible side effects are; and

• what happens after your injection.

If you have any questions, please speak to your GP or other relevant health professional.

What is a trigger point injection?

Trigger points are painful “knots” in your muscles. These "knots" can be very sensitive to touch or pressure.

Usually, muscles contract and relax. At trigger points, the muscle might fail to relax, forming a knot or tight band of muscle. Sometimes you can feel these "knots" when you rub your muscle.

• Trigger point injections contain local anaesthetic with a small amount of steroid. 

• The injection is usually given into the muscles at the shoulders, neck, or back.

• Several injections are usually given during one session.

• The injection may be given alongside other treatments, such as physiotherapy.

How will this injection help?

A trigger point injection can help relieve myofascial pain. Myofascial pain affects your muscles and the fascia (thin connective tissue) around them.

Trigger point injections can also help improve your range of movement. This may depend on which muscle is affected.

What happens during the procedure?

The procedure is carried out as a day case, so you can go home on the same day. It is performed either in Day Surgery or Outpatients, to minimise your risk of getting an infection.

• Shortly before your procedure we may ask you to change into a theatre gown. 

• We will help you get into a comfortable position. This allows your doctor easy access to your trigger point(s).

• Your doctor will clean the area with an antiseptic solution. This can feel cold.

• The doctor may apply slight pressure to the area, to confirm the exact location.

• The doctor injects a local anaesthetic combined with a small amount of steroid into the trigger point. This may sting to start with, but this should ease very quickly.

• The number of injections you have will depend on your number of trigger points. The consultant will examine you and identify the trigger points.

What are the possible side effects?

• There may be some pain, bruising, and / or bleeding at the needle site.

• You may feel a little unsteady when you first stand.

• The procedure may make your pain worse. This should settle within a month.

• There is a small risk of infection at the site of your injections, which may need antibiotic treatment. If your injection site is warm, red, or tender, or you feel hot and unwell, contact your GP or call NHS 111.

• Very rarely, there is a risk of temporary or permanent nerve damage.

If steroids are used:

• Female patients may have temporary irregular periods.

• Diabetic patients may have unstable blood sugar levels.

• Rarely, patients have mood changes.

What will happen after my injections?

• Most patients go home 1 to 2 hours after their procedure, sometimes much sooner.

• You may notice an immediate improvement, but this improvement can take a few days.

• Sometimes there is a slight increase in pain for 24 to 48 hours.

• Steroids work slowly. Even if your procedure has worked well, nothing may seem to happen for a week or two.

Will I need a follow-up appointment?

The Pain Clinic will arrange for a nurse to call you around 6 to 8 weeks after your procedure. We will send you a letter with the date and time of this appointment. 

During this telephone appointment, the nurse will review the outcome of your procedure. They will plan what happens next and discuss this with you. 

If you continue to have good pain relief from the procedure, you may be discharged from the Pain Clinic.

Further information

If you have any concerns about the information in this leaflet or your procedure, please phone the Pain Clinic.

Kent Centre for Pain Medicine and Neuromodulation (direct lines)

• Kent and Canterbury Hospital, Canterbury
  Telephone: 01227 783049

• Queen Elizabeth the Queen Mother (QEQM) Hospital, Margate
  Telephone: 01843 235094

• William Harvey Hospital, Ashford
  Telephone: 01233 616691

Useful information

• East Kent Hospitals. Chronic pain patient information

• Faculty of Pain Medicine of the Royal College of Anaesthetists. Information for adult patients undergoing Trigger Point Injections for the Treatment of Pain.