TESTS AND PROCEDURES

Trigger Point Injection

January 17, 2020

Trigger Point Injection

Male torso showing superficial muscles of back on right side and deep muscles of back on left. Inflammed trigger points are shown.

What is a trigger point?

A trigger point is a tight, painful “knot” of muscle fiber. It can form where a muscle is strained or injured. The knot can sometimes be felt under the skin. A trigger point is very tender to the touch. Pain may also spread to other parts of the affected muscle. Muscles around a knee, shoulder blade, or other bones are prone to trigger points. This is because these muscles are more likely to be injured.

The cause of your muscle pain or spasms may be one or more trigger points. Your healthcare provider may decide to inject the painful spots to relax the muscle. This can help relieve your pain. Relaxing the muscle can also make movement easier. You may then be able to exercise to strengthen the muscle and help it heal.

Cross section of skin and muscle with two fingers compressing muscle for needle insertion.

About the injections

Any muscle in the body can have one or more trigger points. Several injections may be needed in each trigger point to best relieve pain. These injections may be given in sessions about 2 weeks apart, depending on the preference of your healthcare provider. In some cases, you may not feel much change in your symptoms until after the third injection.

Risks and possible complications

Risks and complications are very rare, but may include:

  • Infection

  • Bleeding

  • Lung puncture (pneumothorax)

  • Nerve damage

Updated:  

January 17, 2020

Sources:  

Subacute and chronic low back pain: Nonsurgical interventional treatment, Up To Date, Wong, CSM. A New Look at Trigger Point Injections. Anesthesiology Research and Practice (2012); pp. s1-s5

Reviewed By:  

Fetterman, Anne, RN, BSN,Moe, Jimmy, MD