Patient Information Sheet - Trigger Point Injections

24th December 2006 at 18:33 GMT by Dr C.A.Jenner MB BS, FRCA. Permalink.

Patient Information Sheet on Trigger Point Injections, including indications, methods and adverse effects

What is a Trigger Point Injection?

A Trigger Point Injection (TPI) is a form of treatment for the extremely painful areas of the muscle.

In its active state, a normal muscle is supposed to contract and relax. A trigger point is formed when the muscle fails to relax and knot or tight, ropy band of muscle is formed.

The most common places for a trigger point to occur include the trapezzi muscles of the shoulders, the rhomboids between the shoulder blades and the lower back.

Such a knot or a trigger point can often be felt under the skin and may twitch involuntarily when touched. This is also known as a jump sign.

When is a Trigger Point Injection required?

A TPI is administered to provide relief from painful symptoms associated with the trigger points. The trigger point can trap or irritate the surrounding nerves and cause referred pain .i.e. pain felt in the other part of the body. Over time, such causes may also lead to scar tissue, loss of range of motion and weakness.

Here we list a few of the most common reasons for a trigger point injection to be used:

• Pain in the muscle groups, especially those in the arms, legs, lower back and neck is effectively treated by the TPI.
• TPI is effective in alleviating the myofascial pain syndrome (chronic pain involving the tissue that surrounds muscle), that does not respond to any other form of treatment.
• TPIs are also often used to treat Fibromyalgia and tension headaches.

What is the procedure?

A TPI should only be administered by medical specialists such as an orthopedist, physiatrist, pain specialist or a neurologist. The entire procedure is takes around 30 minutes in all.

The procedure for a TPI generally follows the below steps:

1. Depending on the individual case, the physician may give the patient a nerve block, to prevent pain from needle insertion.
2. The skin over the area to be injected is cleansed with a sterile scrub.
3. Once done, a small needle is inserted into the trigger point and a local anesthetic (e.g. lidocaine, procaine) is injected, with or without a corticosteroid.

Will I experience any side effects?

The most prominent after-effect of a TPI is numbness from the anesthetic, which may last for about an hour. A bruise may also form at the injection site.

It is important that you contact the physician if redness or swelling develops. In some cases where a muscle near the ribcage receives a trigger point injection, there is a risk for puncturing a lung or the membrane that surrounds the lung (the pleura).

It is normally advised to alternatively apply moist heat and ice for one or two days for pain relief. Most often, stretching exercises and physical therapy are performed after the TPI has been administered.