Last updated: Oct 11, 2021

What Are Trigger Point Injections?

Trigger points are small painful focal areas of muscle contractions, or “knots,” that are in spasm and do not relax. These trigger points sometimes can be felt under the skin and may irritate the surrounding nerve tissues causing referred pain to another part of the body.

Trigger point injections help treat chronic muscle pain and other conditions affecting the musculoskeletal system. Muscle pain can occur for a variety of reasons, ranging from mild to severe. It can happen while sleeping in the wrong position and tear large muscle groups during a heavy weightlifting session. Muscle pain usually goes away on its own after a few days of rest, but some types of pain can become chronic and thus require medical attention. Chronic muscle pain can significantly impact a person’s ability to function and carry out their daily responsibilities. Trigger point injections aim at providing immediate relief to those suffering from such pain.

A trigger point injection treats myofascial trigger points, which cause chronic muscle pain. Myofascial trigger points are highly sensitive bundles of fibers in tight bands of muscle. When using an injectable medication, the effect is delivered directly to the myofascial trigger point. The severity and cause of the pain determine the type of medicine used.

Trigger point injections come in various forms, including local anesthetics, corticosteroids, and botulinum toxin A. (Botox). Local anesthetics block pain receptors in muscles, whereas corticosteroids reduce inflammation in muscles and the connective tissues surrounding a nerve. Botulinum toxin A (Botox) inhibits muscle contractions by interfering with nerve signaling pathways. Your doctor injects the medication through a small needle inserted into the myofascial trigger point. Those who have tense muscles may feel a crunching sensation as the doctor inserts the needle. This sensation usually goes away as soon as the muscle relaxes.

Which Conditions Can Trigger Point Injections Help With?

A trigger point injection can aid in the treatment of a variety of conditions, including:

Myofascial pain syndrome. Trigger point injections can help myofascial pain syndrome patients manage their pain better by stimulating responses in unrelated parts of the body that result in referred pain. The affected muscles are then relaxed while pain signaling is disrupted. Poor posture, psychological stress, repetitive motions or injury, and muscle trauma are all potential causes of myofascial trigger points.

Those suffering from myofascial pain may also experience pain in specific parts of a muscle, muscle stiffness or weakness, a limited range of motion, muscle knots that they can only feel by touch, or pain that becomes more intense when they stretch or move the affected muscle.

Fibromyalgia. This condition has symptoms similar to arthritis, but it affects the soft tissue rather than the joints. Although the cause of fibromyalgia is unknown, certain risk factors can contribute to it. These factors include a history of autoimmune disorders such as lupus or rheumatoid arthritis, infections, physical or psychological trauma, being female, a family history of fibromyalgia, and others.

Some fibromyalgia symptoms include headaches, digestive problems, numbness in the hands and feet, tingling, difficulty concentrating, poor sleep, daytime fatigue, symptoms of depression or anxiety, and pain and stiffness throughout the body. Contrarily to myofascial pain syndrome, which leads to localized muscle pain, fibromyalgia leads to widespread or systematic pain.

Headache. According to recent research, trigger point injections can also help patients suffering from headaches.

Trigger point injections do not have the same effect on everyone. Some people experience immediate pain relief after the injection, while others must wait several days or weeks before noticing a difference and improvement in their pain. In some cases, people do not benefit from trigger point injections at all.

Some researchers are looking into how trigger point injections can help people who have abdominal muscle pain. The study’s participants detected a pain reduction in such cases, but only two years after their trigger point injection. Other participants experienced no significant change. Trigger point injections can provide various benefits, but there are many cases where the treatment has no effect.

Do Trigger Point Injections Lead to Side Effects?

Trigger point injections can also cause the following long-term and immediate side effects:

  • Bleeding, dizziness, and lightheadedness;
  • Pain or temporary numbness around the injection site;
  • Discoloration and dimpling of the skin near the injection site;
  • Severe muscle damage, also known as myonecrosis.

It may take three to four weeks for such injections to heal. Pain, swelling, and tenderness near the injection site usually subside after a few hours. If a side effect does not go away after a few weeks, you should consult your doctor.

What Are the Risks of Trigger Point Injections?

Though rarely, trigger point injections can cause severe complications, including:

  • Bruising and infection at the injection site;
  • Nerve and muscle damage;
  • Collapsed lung due to buildup of gas or air between the lungs and the chest wall.

An ultrasound imaging technique can help reduce the risk of a severe complication following trigger point injections.

Trigger point injections are a wise and beneficial treatment for various chronic pain conditions, including fibromyalgia, myofascial pain syndrome, and tension-type headaches. Your doctor or another healthcare provider can administer the trigger point injection directly into the affected muscle. Trigger point injections work differently for each individual. Speak with your doctor about the benefits, risks, and complications of a trigger point injection, as well as whether it is the best option for you.

This page was published on Jul 20, 2017, modified on Oct 11, 2021 by Dr. Freeman (Pain Management Specialist) of Redefine Healthcare
Dr. Eric D. Freeman, a highly regarded pain specialist

Dr. Eric D. Freeman, a highly regarded pain specialist in New Jersey, is board-certified and fellowship-trained in Interventional Spine and Pain Management and Physical Medicine and Rehabilitation. He is an expert in minimally invasive spinal procedures and non-surgical orthopedic care.

Dr. Freeman is a member of the American Academy of Physical Medicine and Rehabilitation and the Interventional Pain Practice Society. In addition, he serves as the Immediate Past President of the New Jersey Society of Interventional Pain Physicians. Dr. Freeman is well-known in the field of pain management as a leading pain management doctor, having been named one of "America's Top Physicians."