This site complies with the HONcode standard for trustworthy health information:
verify here.

Trigger zone injection

If you are considering having a trigger zone injection or have a procedure planned, it is important to know all you can about it. This includes:

why you need this procedure
what it will be like
how it will affect you
what risks are involved
any alternatives.

The information here is a guide to common medical practice. Each hospital and doctor will have slightly different ways of doing things, so you should follow their guidance where it is different from the information given here. Because all patients, conditions and treatments vary it cannot cover everything. Use this information when making your treatment choices with your doctors. You should mention any worries you have. Remember that you can ask for more information at any time.

What is the problem?

You have a painful condition affecting one or more muscular areas. This is usually due to a tender spot in a muscle, which has a small ‘knot’ in it. This muscle knot may be the result of an injury. It may also be an effect from underlying inflammation or wear and tear (degeneration). Inflamed joints are one example, where the overlying muscles become stiff and painful.

What is a trigger zone?

A trigger zone is where there is a particular tender point in a muscle. Pressure on this tender point will ‘trigger’ your pain. For example, a trigger zone on top of the shoulder, when pressed, may send pain shooting up the neck or down the arm. The particular spot that produces the pain may be referred to as a ‘trigger point’.

What is a trigger zone injection?

Trigger zone injections are used to treat a number of different painful conditions. As the name suggests, the injections are usually given into a particular point in a muscle that ‘triggers’ or starts off your pain. The needle is inserted through the skin and underlying tissues, and then pushed into the trigger point.

Local anaesthetic and anti-inflammatory steroid drugs can be injected into the trigger point. Painful conditions affecting one or more areas can be treated in this way. Only a small amount of steroid is needed and it will not cause any of the side effects sometimes associated with taking steroid tablets. They are not the same kind of steroids that athletes may take.

What has gone wrong?

It is not always clear why trigger zones develop. They can be associated with various illnesses, such as fibromyalgia, myofascial pain and chronic fatigue states. Trigger zones may be related to underlying inflammation. Often they occur because of lack of use of a muscle, when pain of whatever cause has been present for a long time.

The aims

The aim of the procedure is to reduce the spasm and ‘unknot’ the muscle. This lowers the sensitivity of the trigger zone, which reduces the pain messages. It is hoped that this will produce long lasting relief from your pain.

The benefits

Your pain should be reduced and you should be able to move around more easily. This will make it easier to perform your daily activities. You will be able to reduce the number of painkilling tablets that you take.

Are there any alternatives?

By the time that you consider having the trigger zone injection you should have already tried other more simple treatments. These include rest, both pain-killing and anti-inflammatory tablets, and physiotherapy.

You may also have tried a transcutaneous electrical nerve stimulation (TENS) machine for your pain. This works by sending soothing pulses across the surface of your skin and along the nerve fibres. The pulses prevent pain signals from reaching the brain. They also stimulate your body to produce higher levels of its own natural painkillers, called endorphins.

What if you do nothing?

If you do nothing there are several things that may happen:

With time and rest the pain may settle on its own
The pain and difficulty in moving may remain the same
The pain may increase

Who should have it done?

The following patients should have the procedure done:

Patients with easily identified, painful trigger zones

Who should not have it done?

Each patient must make the final decision on whether to proceed or not. If you are unhappy about the procedure for any reason you should not continue.

There are specific medical situations when trigger zone injections should not be done and they are as follows:

When a patient is on medication that prevents blood from clotting, such as warfarin. This would lead to more bleeding than normal. It may be possible to stop the medication a few days before the procedure. This will need to be discussed with your doctor
When a patient is suffering from an illness that prevents blood from clotting, such as haemophilia. This would also lead to more bleeding than normal
When there is infection of the skin over the site where the needle needs to be put in. This could lead to deeper infection

Author: Dr Sean White FRCA. Consultant in pain and anaesthesia