Trigger Point Injections

A trigger point injection (TrPs) is a procedure that involves injecting a local anesthetic into a specific area of muscle or tissue where a trigger point is located. The injection is intended to relieve pain associated with the trigger point.

Trigger Point - pain in a skeletal muscle that is associated with at least two of the following: a hyperirritable spot, taut band and referred pain, a knot of pain.

Trigger Point Injection (TrPs)- an invasive procedure where medication is injected directly into a trigger point.

The exact mechanism of TP injection benefit is still unknown.

Anesthetics used:

- Bupivacaine (Marcaine) Long-last anesthetic (used for blocks) has an onset of 5 min and lasts for 4 to 8 hours

- Lidocaine (Xylocaine) has an onset of just a few minutes lasts for 30 minutes to 3 hours

- Some medical providers use a steroid as well.

Trigger point injections are associated with some risks:

pain
bleeding
allergic reaction to the anesthetic
formation of a hematoma, or a severe bruise
infection

All patients should be starting or continuing Pelvic Floor Physical Therapy (PFPT), the gold standard to heal hypertonic pelvic floor muscles and Botox, in conjunction with TrPs to reach the goal of returning pelvic floor muscles to normal therefore ending pudendal nerve pressure and pain.

Procedure - WOMEN

This procedure is done in an office and takes 15-30 minutes.

The patient is awake.

The patient is placed face-up in the lithotomy position (arms to the

sides, but the legs are separated, raised, and supported by stirrups).

TP injections should be performed by a urogynecologist

experienced in the technique.

Each TP was identified vaginally by palpation using a finger. A flexible 6 inch, 25 gauge needle is put into the vagina and into the trigger points (knot) as confirmed by palpation.

After a trigger point injection, you can go home and can actively

use the affected muscle. However, you should avoid strenuous activity for the first few days.

Some studies report people experience pain relief starting between 24 and 72 hours after the trigger point injection procedure. Other studies report some people experience no pain releif. The results are mixed.

NOTE: PNE spoke to one experienced urogynecologist who offers sedation if she and the patient feels they need it. This urogynecologist said in her opinion that inserting needles several times into the vagina is painful.

Procedure - MEN

Just as with women, this procedure is done in an office. The patient is awake.

The patient is placed face-up in the lithotomy position (arms to the sides, but the legs are separated, raised, and supported by stirrups).

TP injections should be performed by a urologist and

sometimes a urogynecologist if there is no urologist in

the area. The doctor should be experienced in the technique.

Each TP was identified transrectally by palpation using a finger.

A flexible 6 inch, 25 gauge needle is put through perineum

and into the trigger point (knot) as confirmed by palpation.

After a treatment trigger point injections, you can go home

and can actively use the affected muscle. However, you should avoid strenuous activity for the first few days.

Some studies report people experience pain relief starting between 24 and 72 hours after the trigger point injection

procedure. Other studies report some people experience no pain relief. The results are mixed.

NOTE Warning: You should first be diagnosed for pudendal neuralgia and hypertonic pelvic floor muscles through the five Nantes Criteria before seeking out trigger point injection treatments.

Based on reading the PN Facebook pages since 2018 and roughly eight Zoom calls with members, it is clear that some doctors and medical providers perform too many TPIs too often, actually putting patients at risk. Some medical providers give the injections once a week, without a diagnosis. TPI are covered by insurance so profit can trump the welfare of people. You will read different timelines, but not are short than 30 days. Most doctors recommend three months and that's if they help your pain. We must be the guardians of our bodies and pocket books. Anyone who treats pudendal neuralgia knows that patients are desperate.

The literature that is available on Trigger Point Injections (TrPs) for pelvic floor pain reports that the duration of effect after a trigger point injection is variable. There is wide variability in protocols ranging from repeating injections monthly verses every 3-4 months.

“A 2023 review of the literature concludes that while randomized trials have found statistically significant improvement related to TPI, the studies are limited by the low number of participants, lack of blinding, potential for placebo effect.

The studies are inconclusive regarding a single pharmacological agent (anesthetic) proving superiority to another. Evidence rating B is inconsistent or limited quality patient-orientated evidence. The following received an evidence score of B: placebo effect may be the underlying source of pain of relief from TPI.

Pelvic Floor Physical Therapy and massage should be considered first as TPI is more invasive.

"Due to the paucity of well-designed studies, it remains difficult to draw definitive conclusions regarding the

additive benefit of corticosteroids for TrP injections. Due to the rare but potentially severe side-effects of corticosteroids, practitioners should consider injection of a local anesthetic alone for the initial treatment of myofascial TrPs. Furthermore, the frequent dosing of corticosteroids of unclear benefit may greatly increase the cumulative exogenous corticosteroid burden on our patients, and limit their candidacy for other interventional pain

management injections."

There is some evidence that the benefit may be due to the primarily to the insertion of the needle into the

muscle (“dry needling”) and not necessarily the substance injected. A large double-blind study is needed as soon as possible.

Though many practitioners can attest to improvement in pain levels of hypertonic pelvic floor muscles, it is measured using self-reports of pain levels pre- and post-treatment. To date, the number of randomized, placebo-controlled trials is few, and most of them have small numbers of participants. Additionally, because they rely exclusively on self-reports, there remains uncertainty about the validity of the findings. Thus, while a variety of pharmacological and nonpharmacological treatments have shown efficacy, studies of proper size and quantitative outcome measures need to be performed.

_____

Pudendal Neuralgia Alliance

contact@pudendalneuralgiaalliance.org