published in TOGS September 2006
point injections in chronic pelvic pain
Dr.Shobhana Mohandas.MD.DGO. FICOG.Dip.Endoscopy: Chief Gynaecologist & Endoscopic
Sun Medical Centre, Unit of Trichur
Chronic pelvic pain is a
common vexing problem faced by the gynaecologic
patient the world over. Aetiological factors for this problem are varied. Pelvic
pain could be caused by pelvic inflammatory disease, pelvic adhesions, pelvic venous
congestion, endometriosis, ectopic pregnancy,
fibroids, ovarian cysts, or neoplasms. In the acute phase, medical or surgical
treatment may be required for any of these aetiologic
factors. Once the acute phase
treatment is over, the patient, sometimes, may be left with a nagging pain
which she may describe as: “I get pain when I strain to bend, or turn”,or. “
I get pain when I press on my abdomen”. This type of pain may ensue commonly
after abdominal surgery, like LSCS or abdominal hysterectomy, but may also
follow treatment for acute pelvic inflammatory disease.
examination, pelvic examination will reveal non-tender uterus and ovaries.
On examining the abdomen, on pressing the abdomen, tenderness will be
elicited in specific spots in the abdomen, anywhere from the umbilical area
to the pubic symphysis. These are patients with pain in the
abdominal wall, produced by fibrotic bands in the
abdominal wall, which could be called, “Trigger Points”. The pain is
usually mild, but irritating to the patient and may cause physical and
mental agony. The treating
physician, quite often, for want of finding sufficient physical findings,
may refer to it, as “functional”.
Such “Trigger Points” could be managed successfully with local
injections of anaesthetic into the specific
points. What follows is a
description of this less researched modality of treatment for chronic pelvic
The first medical textbook that took the
position that muscles cause pain was published by J. Travell
and D.G. Simons in 1983. As
discussed in this text, the hallmark of myofascial
pain is the
presence of one or more trigger points in muscles. Trigger points are hyperirritable bundles of fibers within a muscle
which become "knotted" and inelastic, unable to contract or
relax, due to an injury. A focus of
hyper-irritability in a tissue that, when compressed, is locally tender
and, if sufficiently hypersensitive, gives rise to referred pain and
tenderness, and sometimes to referred autonomic phenomena and distortion of
oxidative-dysoxygenative dysfunction (ODD) was
proposed by Majid Ali as the systemic molecular
pathogenetic model of fibromyalgia
for all of its symptom-complexes.
The three primary molecular phenomena in ODD are oxidosis, dysoxygenosis
(abnormal oxygen metabolism), and acidosis.
Trigger point sites show accumulation of fat droplets designated
"fat dusting"; variations in width and intensity of staining of
muscle fibers; nuclear enlargement and endomysial
as well as perimysial nuclear clustering; fiber
degeneration, contracture knots (club-like enlargement of myofibrils in
vicinity of empty sarcolemmic tubes); and
interstitial infiltration of metachromatic mucopolysaccharides. Ultrastructural
abnormalities in TP tissues include the following: mitochondrial swelling,
moth-eaten appearance of myofibrils, giant (double length) sarcomeres, disrupted sarcomeres,
and excess collagen in advanced cases on histopathology. The ODTP hypothesis (Oxidative dysoxygenative trigger point hypothesis) proposes that
tender points develop as a result of accumulation of pools of oxidized and
stagnant lymph (as well as oxidized and denatured blood components) within
muscles, tendons and ligaments. Removal of such oxidized lymph clears the
way for healing.
Selecting a patient with
chronic pelvic pain for Trigger point injections:
When abdominal pain is chronic and unremitting,
with minimal or no relationship to eating or bowel function but often a
relationship to posture (i.e., lying, sitting, standing), the abdominal
wall should be suspected as the source of pain.
Pain that is the same or
increased when the abdominal wall is tensed generally indicates an origin
in the abdominal wall. Pain caused
by intra-abdominal causes should be ruled out by noting the absence of
associated symptoms like nausea, vomiting, diarrhea, physical findings like
tender masses in the pelvis, etc.
Abdominal wall pain is chronic, nagging and non-progressive. Tenderness originating from inside the
abdominal cavity usually decreases when a supine patient tenses the
abdominal wall by lifting head and shoulders off the examining table. In
contrast, pain originating from the abdominal wall is unchanged or
increased by this maneuver (positive Carnett's
sign). A tender trigger point in the
abdominal wall is frequently no more than 1 or 2 cm in diameter. However,
it is not unusual for the pain to spread over a wide area or to be referred.
In a gynaecologic
practice, this sort of pain usually follows abdominal surgery.
100 cases for whom Trigger point injections were
tried at Elite
by the author, most of the cases were patients who had undergone previous
surgery. Trigger point injections
can also be used as a diagnostic test in ruling out other causes of pelvic
pain. If the pain totally subsides
with TPI(Trigger point injections) no subsequent
treatment need be given. If not, a
diagnostic/therapeutic laparoscopy may be needed in indicated cases.
How do Trigger point injections work?
Trigger point injections
act by the following mechanisms:
1) Mechanical disruption of the abnormal
contractile elements, which may result in the relief of muscle tautness and
2) Fluid injections, which may dilute
nerve-sensitized substances that may be present
3) Muscle fiber damage, which may release
intracellular potassium, causing a depolarization block of nerve fibers
4) Feedback mechanisms
between the central nervous system and the trigger point, which may be
5) Focal necrosis caused
by the anesthetic agent, which could contribute to the destruction of the
trigger point injections given?
There are not very
many research articles on Trigger point injections and many workers use
various methods in giving these injections.
The method used by the author in treating about 100 patients in the
past 5 years is described below. The
patient is selected carefully, making sure there is no acute abdominal
cause of pain. She is given
realistic expectation of how much pain relief to expect after trigger point
injections. On palpation of abdomen, there should be tender areas on touch
and pelvic examination should not reveal any areas of tenderness. All the fornices
should be palpated deeply and bimanually in a careful manner to look for
deep seated areas of tenderness. If
there are areas of tenderness, it is caused by pelvic infection/endometriosis/pelvic
venous congestion. They should be
treated as such.
The selected patient
is asked to lie supine. A 20 cc
syringe is filled with 2cc containing 100mg hydrocortisone (1 vial of Primacort) , 3-4 cc 2% Lignocaine, and about 15cc distilled water. Steroids
presumably reduce inflammation or result in the thinning of connective
tissue around painful nerve roots. A lignocaine
sensitivity test should be done for patients who have not previously
undergone testing for hypersensitivity.
The patient is asked to show where her pain usually comes. The tender area is localized, if possible
with a finger. It is not always possible to localize with a finger. The area is swabbed with methylated alcohol and a 21 guage
needle attached to the 20 cc syringe is then inserted in the abdominal
wall. The patient is asked to report
pain , when a painful point is reached. For example, the needle is inserted in
one point and the patient is asked, “Do you have pain?” She may say
no. The needle is withdrawn a little
bit, and re-inserted in another direction.
When a trigger point is reached, she would wince with pain and say,
“ Oh yes, it is painful”
1-1.5cc of the
solution in the syringe is injected at that point and the injection is
usually very painful. The needle is
again withdrawn a little without taking it out of the skin and reinserted
in other areas to look for other trigger points. In this manner, all the trigger points in
this area are injected with 1cc of diluted lignocain-cum-hydrocortisone.
The needle is now
taken out of the skin and other tender areas sought on the skin. The procedure is repeated there. The depth of the needle is not fixed and
may depend on the thickness of the abdominal wall.
Apart from 2-3
patients, treated by the author, all patients have been cured of pain. The patient continues to have pain at the
points where the needle was inserted for 3-4 days, but after that she stays totally
pain free. No patient has been given
repeat injections under the author’s care, although many other workers have
mentioned repeat injections in studies involving trigger point injections
in many sites in the body.
3 elderly patients had vaso-vagal
syncope after the treatment. It
subsided with rest and IV- fluids. There
was no need for hospital admission.
injection therapy is a very effective therapy for abdominal pain of myofascial origin.
It should be tried in all patients with pelvic pathologiesbefore
going in for surgical remedies, if the pain seems to have a myofascial component to it in addition to the abdominal
pathology. This will lead to the
patient being more satisfied post-surgically. It should be tried in all post surgical
patients complaining of chronic nagging pain. Immediataely
after surgery, a reasonable time should be given for the post-surgical
inflammatory response to subside.
But if it persists for a long time, instead of asking the patient to
put up with the pain or labeling her functional, a trial of trigger-point
therapy would go a long way in alleviating the suffering of the
Saud Suleiman: The Abdominal wall :
an overlooked cause of pain:
Laurie Barclay: ACOG Issues New
Guidelines for Chronic Pelvic Pain : Obstet Gynecol.
Paper on Trigger Point Injections [Fibromyalgia
and Myofascial Pain News: www.immunesupport.com
James Carter,John Slocumb: OBGYN.net Conference Coverage From IPPS - Simsbury, Connecticut
- April/May, 1999: www.obgyn.net.
Shobhana Mohandas: Chronic Pelvic Pain: Desk top Reference
in Gynaecology: 2000: PUbl:
Majid Ali: Oxidative-Dysoxygenative Trigger Points in Fibromyalgia Pathogenesis, Diagnosis, and
Resolution : J of Integrative Med 1999;3:38-47.