Chronic Pelvic Pain: Trigger Point Injections

What are trigger points?

What causes trigger points?

How are trigger points treated?

Do trigger point injections hurt?

What is the benefit to me?

What are the risks of trigger point injections?

Can trigger point injections make the pain worse?

What is "rebound pain"?

     Also See:

                   Chronic Pelvic Pain: Bladder Pain Treatment

                   Chronic Pelvic Pain: EFUDEX (5FU) for Vulvadynia

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What are trigger points?

Trigger points are painful tissues in and around muscles and fascia. (Fascia is a type of tissue that separates and supports most structures within the body.) For women with pelvic pain, these tender areas are often found in the lower abdomen. The abdomen may be tender to pressure with one finger and feel achy or sharply painful. The pain may radiate to the low back or groin and legs. It may also become worse when the woman is experiencing a full bladder, ovulating, or having her period.
 

What causes trigger points?

There are many theories as to what causes this kind of pain. However, the exact reason is not well understood. It is believed that this abdominal wall pain is referred from the pelvic organs (uterus and bladder). That means that the pain is really in the pelvic organs but is felt in the wall of the abdomen. (This is similar to a pain from a heart attack that may be referred, or felt, in the left arm.) Treating the abdominal wall pain may be an important part of making the patient feel better.

Trigger point abdominal wall pain may start or become worse after abdominal or pelvic surgery, pregnancy, or having your period. It may also be associated with such disease as endometriosis, interstitial cystitis (chronic bladder pain) or pelvic infections. Removing the pelvic organs does not necessarily get rid of the pain. (Even without the organs, the nerves still seem to react and cause pain.)
 

How are trigger points treated?

Trigger points can be blocked by a local anesthetic injection. This helps determine if that tissue is a major source of the pelvic pain. Often this produces prolonged relief from the pain (weeks to months).

Other treatments may need to be tried if the painful tissues don’t respond to the local anesthetic in 3-5 treatments. These may include such things as central epidural blocks, neurologic or pain medications or further assessment of pelvic organ disease. Physical therapy and stress reduction exercises may also be helpful.
 

Do trigger point injections hurt?

Actually, if the injection is to work, giving an injection into a tender trigger point (in the abdominal wall) should produce the same pain that the patient usually feels. Injection into nontrigger point tissue causes very little discomfort at all. Most patients can tolerate the pain because it only lasts for a few seconds or minutes. Then the local anesthetic actually blocks the pain of injection as well as the trigger points. A few patients require pre-injection pain medications to help deal with the severity of their pain. Cold spray-chlorohydrate.
 

What is the benefit to me?

Blocking trigger points should ease your pain. The relief you get lets us know we are treating you in the most effective way. With the first treatment you may get a few days of relief or you may get weeks to months of relief. You need to let the health care team know how you feel.
 

What are the risks of trigger point injections?

Besides reproducing your pain for a few minutes, you may also have bruising or aching in the area of the injection. (This is caused by the needle used for the injection.) This is not dangerous and is usually helped with mild pain medications like Tylenol and placing heat on the spot.

For a short time (1-2 hours) you may have numbness and muscle weakness in your leg. This is caused by the local anesthetic blocking the nerves to the thigh. There are no long-term effects from this. The “numbed nerves” return to their normal function when the medication used in the block wears off.

Other rare complications include infection at the site of the injection, possible injury to the bowels or bladder from the needle, or bleeding from injured blood vessels. These complications are very rare and we take extreme precautions to avoid them.
 

Can trigger point injections make the pain worse?

It is necessary to find and reproduce your pain in order to tell where it is coming from. However, most of the time the pain from the injection and the pain in the abdominal walls are blocked by the local anesthetic. This pain is not only blocked until the medication wears off (2-4 hours), but also for an extended period of time-days to months. This indicates we have blocked a nerve feedback cycle.

Occasionally patients note that after 1-2 days their pain has returned and may be worse. This “rebound pain” is from trigger points that are next to those blocked and were not as dominant at the time of the exam. Reinjecting these areas is often all that is needed. This also explains why the abdominal wall needs to be blocked from 3-5 times in order to get all the points and produce the best result.
 

What is "rebound pain"?

Some patients may experience what is known as “rebound pain” following their trigger point injections. Besides reproducing your pain for a few minutes, you may also have bruising or aching in the area of the injection. The needle used for the injection causes this. This is not dangerous and is usually helped with mild pain medications such as Tylenol, Ibuprofen and by placing ice then heat on the spot. Occasionally patients note that for 2-3 days after injections their pain has returned and may be worse. This is rebound pain, which results either from bruising, or from trigger points that are next to those blocked. Trigger points that were not blocked, or were not as dominant at the time of exam may flare up after others are treated. Re-injecting these areas during your next visit is usually all that is needed. This also explains why the abdominal wall needs to be blocked from 3-5 times to produce the best results.

If you experience any of these symptoms, you should proceed with the self-treatment options that are available to you. Alternating ice and heat, taking Tylenol, Aleve, or Motrin and a day of decreased activity should help resolve your rebound pain. It is acceptable for this pain to last for up to a week.

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