Pelvic Abnormalities: Endometriosis: Pelvic Pain

Endometriosis may cause pain. Classically, the pain of endometriosis is most intense during the menstrual flow (dysmenorrhea) and it may involve a wide range of pelvic and abdominal regions. The pain may also be associated with intercourse (dyspareunia) that lasts for several hours after the conclusion of relations (since vaginal penetration commonly results in the movement of pelvic structures most often affected by endometriosis). The cyclic nature of the pain is based on the extraordinary responsiveness of endometrial tissue (wherever located) to the sex steroids, estrogen and progesterone.

During the menstrual cycle, the ovary produces a tremendous amount of estrogen and progesterone in a sequence that promotes an orderly growth of endometrium. If a pregnancy does not occur, then the uterine lining sheds predominantly through the uterine cervix and out the vagina as menstrual flow. If the patient has endometriosis, the endometrial cells that are ìshedî in the pelvis have no escape from the body and often cause a dramatic local inflammatory reaction. This inflammation is the most widely accepted cause for the pelvic pain associated with endometriosis.

The pain of endometriosis can range widely from a dull ache to a severe piercing sharp pain. Typically the pain lasts for days starting 1-2 days prior to the onset of the menstrual flow. The pain may be greater in certain locations, but often involves the

… midline pelvis (around and behind the uterus)

… adnexal region (around the ovaries and tubes immediately lateral to the uterus)

… lower back deep in the pelvis (around the rectosigmoid colon or uterosacral ligaments behind the uterus) where it is often thought to be gastrointestinal

… pelvis with radiation down one or both legs or into the groin

Endometriosis and Pain: treatment

Management of the pain associated with endometriosis using medications is reported to be frequently (in up to 85% of women) effective. Medical management often takes 3-4 months to become effective and many of these medications can only be given safely for up to 6 months. Therefore, the woman suffering from the endometriosis will often request more immediately effective treatment. Surgery is clearly an alternative with a typically rewarding outcome. I have generally recommended consideration of surgical intervention (operative laparoscopy) at the point when the woman's pelvic pain interferes with her daily activities to such an extent that she would rather have a surgical procedure to try to remove the source of the pain than continue with the pain.

All the medical management options for treating endometriosis include medications that temporarily prevent pregnancy by disrupting ovulation. To be perfectly safe, one should consider contraception after initiating these medications until a state of anovulation is achieved. Clinical reports comparing the various medications in terms of effectiveness in pain management suggest that they are generally comparable to one another. Many of these medications have significant side effects that the patient may find disagreeable. The medications in use today include

(1) GnRH agonists,
GnRH agonists essentially turn off the ovary in terms of egg maturation. The dramatic decrease in circulating estrogen is thought to be the primary mechanism of action for GnRH agonists in the treatment of endometriosis.

One should be certain that the patient is not pregnant or able to become pregnant before the ovary is suppressed with a GnRH agonist. The effect of agonist treatment on pregnancy is not known. There is a report in the literature describing an uneventful pregnancy and delivery of a normal baby despite GnRH agonist therapy effectively for the first 3 months of pregnancy (injections at 4 and 8 weeks).

The effectiveness of the GnRH agonists is comparable to Provera and Danazol with respect to treatment of the pain associated with endometriosis. Excellent large studies (prospective, randomized, controlled clinical trials) have demonstrated that GnRH agonists and Danazol have comparable effects on endometriosis in terms of pain and reduction of visible disease (determined by comparing pre and post treatment findings at laparoscopy).

There have been no reports demonstrating a benefit in the treatment of stage I or II endometriosis with GnRH agonists in terms of fertility.

(2) Progestagens,
Progesterone counteracts the effect of estrogen on the endometrium. The mechanism for this includes a progesterone stimulated reduction in estrogen receptor number (so estrogen in the circulation has fewer cellular receptors to bind resulting in less effect), an accelerated metabolism of estrogen to less active and inactive forms that are rapidly excreted, and an inhibition of some of the molecules formed as a result of estrogen that help in creating the ìestrogen effect.î

The effectiveness of Provera in providing relief for the pain associated with endometriosis is reported to be comparable to that of Danazol and the GnRH agonists.

There is no apparent benefit of Provera or other medical management in the treatment of stage I or II endometriosis with respect to fertility. In a solid research study (prospective, randomized, placebo controlled clinical trial) there was no significant difference in the pregnancy rates following Provera treatment (100 mg per day) of stage I or II endometriosis compared to placebo (inert tablets without medication).

(3) Danazol,
Danazol was widely used when introduced into clinical practice in 1972 because it was the only medication available. It is consistently effective in treating pain associated with endometriosis. At this time, Danazol is not used much since equally effective medications are available and the side effects of Danazol can be undesirable.

Side effects of Danazol include weight gain and fluid retention, decreased breast size, acne and oily skin, excessive male pattern hair growth (facial, chest, back), mood swings, muscle cramps, fatigue, irreversible deepening of the voice, hot flashes, and atrophic vaginitis (with decreased elasticity of the wall of the vagina). Side effects occur in about 80% of women but only 10% of those who take the medication actually discontinue the medication because of the side effects. Most young reproductive age women find these sorts of side effects to be highly unattractive and prefer to use one of the other available medications if medical management is chosen for treatment.

Danazol is effective in relief of pain due to endometriosis about 90% of the time, has similar efficacy to GnRH agonists and Progestagens, and the pain will reportedly return in about a third of patients within a year.

There is no known benefit for the treatment of infertility associated with stage I or II endometriosis.

(4) Surgery
Surgical considerations in treating the pain associated with endometriosis should incorporate what is known about the nerve supply to the affected pelvic structures. The primary goal is generally to remove (ablate) all visible endometriosis. Wide margins in the areas of known pain can be considered (for treatment of microscopic foci of endometriosis) when using a tool like the ultrapulse laser since it has little lateral thermal damage and postoperative adhesion formation appears to be minimal.

Sensory nerves help to carry the signal of pain to the brain. If there are no sensory nerves functioning in an area of the body then this area is incapable of feeling pain. For example, if the sensory nerves to a person's hand have been destroyed then that person will not be able to ìfeelî with the hand. If the hand is accidentally hurt (pinched, burned, cut) the affected person may not notice the damage until the damage is sensed via vision.

The sensory nerve supply to the pelvis can differ in amount between different women. This is most commonly believed to be the reason why some women have incapacitating pain with minimal endometriosis (lots of nerve endings in the areas of endometriosis) while other women have no pain at all despite massive endometriosis (few nerve endings in the areas of endometriosis).

Pelvic organs receive their sensory nerve supply from the autonomic (sympathetic and parasympathetic) nervous system. The sensory innervation of the fallopian tubes, uterus and upper vagina is predominantly via sympathetic fibers at the spinal cord level of T-10 to L-1 (area of the lower back).

To reach the spinal cord, nerves from the uterus generally travel through ligaments behind the cervix (the uterosacral ligaments) to a ìuterine plexus.î Other uterine nerves join other sensory nerves from the pelvis and follow the uterine arteries to an ìinferior hypogastric plexus = pelvic plexusî which is at the level of the vagina and rectum. Sensory nerves from the upper vagina, cervix and lower uterus may also travel through parasympathetic nerves to the sacral spine (at S-2 to S-4) via the paracervical ìFrankenhauser's plexus.î Ovarian sensory nerves travel independently with the ovarian arteries to an ìovarian plexus.î Importantly, converging nerve fibers from these networks (that supply the pelvic structures most commonly associated with endometriosis) pass through a common ìsuperior hypogastric plexus = presacral nerveî

Surgical transection or removal of the nerves that carry pain sensation from the pelvic structures most commonly associated with endometriosis has been performed for some time. For midline pain, the uterosacral ligament transection (also called ìLUNAî = laparoscopic uterine nerve ablation) is occasionally beneficial. For recurring severe pain throughout the pelvis, a presacral nerve ablation (neurectomy) can be considered.

I have generally had good results with the aggressive removal of all visible foci of endometriosis. For women with little relief or recurrent endometriosis, the uterosacral ligament transection and presacral nerve ablation can be considered. The serious potential complications with the presacral nerve ablation (neurectomy) have limited the use of this treatment.

Chronic Pelvic Pain

Chronic pelvic pain (CPP), pelvic pain lasting longer than 6 months, is one of the most common gynecologic complaints. This pain may be episodic or continuous, with variations in intensity but never or rarely completely absent. Episodic pain may be associated with intercourse (dyspareunia), menstruation (dysmenorrhea), or ovulation (mittelschmerz).

Neuronal Pathways in the Pelvis

A review of the neuronal pathways is necessary in order to understand the pathophysiology of pelvic pain.

The pelvic viscera receive their innervation via the autonomic nervous system. The sympathetic portion originates from the thoracolumbar area of the spinal cord. The parasympathetic supply follows the distribution of the vagal nerve in combination with parasympathetic fibers from S-1, S-2, and S-3. The autonomic nerve fibers enter the pelvis by following several routes. Most of them contribute to the formation of the superior hypogastric plexus.

The fact that most of the pelvic viscera share their sensory innervation explains why pelvic pain is a nonspecific symptom for the dysmenorrhea.

The perception of pelvic pain, however, does not involve only the transmission of painful stimuli from the periphery to the center of the nervous system (brain). The gate-control theory was developed to explain the interaction between painful stimuli and the emotional and motivational state of the individual.

Table 1. Causes of Chronic Pelvic Pain

Reproductive system Mittelschmerz Primary dysmenorrhea Endometriosis Adenomyosis Leiomyomata Mullerian malformations Uterine retroversion Uterine prolapse Chronic pelvic inflammatory disease Adnexal tumors Pelvic congestion syndrome Cervical stenosis Pelvic adhesions	Urinary system Nephrolithiasis Urinary tract infection Interstitial cystitis Urethral syndrome Cystocele Pelvic kidney
Gastrointestinal system Constipation Irritable bowel syndrome Inflammatory bowel disease	Musculoskeletal system Obturator syndrome Disorders of the lumbo-sacral spine Disorders of the hip joint Pyriformis syndrome Rheumatic polymyalgia Pelvic floor tension myalgia
Diverticulosis Diverticulitis Neoplasms	Neurologic disorders Diabetic neuropathy Multiple sclerosis
Pelvic pain of unknown etiology	Psychiatric disorders Affective disorders Munchausenís syndrome

Etiology of Chronic Pelvic Pain

Chronic pelvic pain may be associated with gynecologic disorders or with other conditions not related to the reproductive organs. For practical purposes we group the different causes of pelvic pain according to the functional system that they affect (Table 1). The most common pathologic conditions diagnosed laparoscopically in patients with pelvic pain are listed in Table 2.

Table 2. Laparoscopic Findings in Women with Chronic Pelvic Pain*

Endometriosis 31%

Adhesions 23%

Chronic PID 7%

Ovarian cyst 4%

Myomas <1%

Pelvic varicosities <1%

Other 4%

Negative laparoscopy 36%

Number of patients 1386

*Modified from Porpora MG, Gomel V. The role of laparoscopy in the management of pelvic pain in women of reproductive age. Fertile Sterile 2002;68:675-79.

The most common reproductive disorder responsible for CPP is endometriosis. In several studies the incidence of endometriosis in women who have undergone laparoscopic evaluation of CPP was in the range of 38%.

Adenomyosis can also cause continuous pelvic pain. Adenomyosis frequently presents with only dysmenorrhea.

Uterine leiomyomas are found in approximately 30% of women of reproductive age.

Pelvic adhesions have been found in up to 23% of asymptomatic patients who underwent laparoscopic tubal sterilization. In several reports the incidence of adhesions in patients evaluated for pelvic pain varies.

Adnexal pathology (neoplasms, endometriomas, adnexal torsion) are more responsible for acute pelvic pain.

Chronic PID can be responsible for CPP, which is probably secondary to adhesion formation. The incidence of chronic PID.

Uterine prolapse and uterine retroversion have been described in patients with pelvic pain. The diagnosis of uterine prolapse is clinically obvious. A retroverted uterus can be associated with CPP, low back pain.

Pelvic congestion syndrome, in the absence of other pelvic pathology, may be responsible for dull pelvic pain with positional exacerbation. The pain may increase during menstruation and after intercourse.

Nongynecologic conditions frequently related to CPP include gastrointestinal disorders. Constipation and irritable bowel syndrome are the most common conditions encountered. Irritable bowel syndrome.

Urologic problems may also be responsible for CPP. Interstitial cystitis can present with pelvic pain associated with urgency, frequency, and urge incontinence. The diagnosis is established by cystoscopy during an intravenous pyelography.

Musculoskeletal disorders may contribute to pelvic pain. Spasm of the levator plate may represent a primary.

Diagnosis

In the evaluation of patients with CPP the history is of paramount importance.

Treatment

Treating patients with CPP represents a major challenge for the managing physician, especially when an extensive workup fails to yield a diagnosis. The development of good patient-physician rapport is of paramount.

Successfully used agents include oral contraceptives, danazol, progestational agents, and recently, gonadotropin-releasing hormone analogs (GnRHa). All these agents act by suppressing the development of ectopically positioned endometrial tissue. Progestational agents suppress the release of luteinizing hormone and thereby prevent ovulation and ovarian steroidogenesis. They also exert a direct effect on the endometriotic implants, inducing decidualization and atrophy. Medroxyprogesterone and megestrol acetate have been used with symptomatic relief in 80% of patients.

Danazol is a 17a-ethinyltestosterone derivative. Its mode of action includes (1) suppression of pituitary gonadotropin secretion, (2) direct binding to endometrial cell receptors, (3) suppression of ovarian and adrenal steroidogenesis.

The GnRHa have been used successfully for several years in the treatment of endometriosis. Reversible suppression of gonadotropin production by the GnRHa eliminates ovarian steroid production. Ectopic endometrial tissue deprived of estrogen.

Serotoninergic antidepressants (trazodone and fluoxetine) as well as tricyclic antidepressants have been used successfully in combination with nonnarcotic medication in the management of these patients.

Alprazolam, a benzodiazepine derivative with mixed anxiolytic and antidepressive effects.

Chronic Pelvic Pain

Background: Chronic pelvic pain (CPP) is a common problem and presents a major challenge to health care providers because of its unclear etiology, complex natural history, and poor response to therapy.

CPP is poorly understood and, consequently, poorly managed. This condition is best managed using a multidisciplinary approach. Management requires good integration and knowledge of all pelvic organ systems and other systems including musculoskeletal, neurologic, and psychiatric systems.

A significant number of these patients may have various associated problems, including bladder or bowel dysfunction, sexual dysfunction, and other systemic or constitutional symptoms. Other associated problems, such as depression, anxiety, and drug addiction, also may coexist.

In the United States, estimated direct medical costs for outpatient visits for CPP (women aged 18-50 y) is approximately $881.5 million per year (Mathias, 1996).

Pathophysiology: The pathophysiology of CPP is complex and multifactorial. It remains unclear.

Frequency:

… In the US: CPP is a common problem. It affects approximately 1 in 7 women (Mathias, 1996). In one study of reproductive-aged women in primary care practices, the reported prevalence rate of pelvic pain was 39% (Jamieson, 1996). Of all referrals to gynecologists, 10% are for pelvic pain (Reiter, 1990).

… Internationally: A similar prevalence of CPP has been described in other countries (Zondervan, 1999).

Mortality/Morbidity: As with other chronic pain, CPP may lead to prolonged suffering, marital and family problems, loss of employment or disability, and various adverse medical reactions from lifelong therapy.

Race: In one study, being African American was found to be a risk factor for pelvic pain (Jamieson, 1996).

Sex: CPP is most common among reproductive-aged women. Common causes of CPP in men include chronic (nonbacterial) prostatitis, chronic orchalgia, and prostatodynia.

Age: CPP is most common among reproductive-aged women, especially those aged 26-30 years (Jamieson, 1996).

History: The proposed definition of CPP is nonmenstrual pain of 3 months duration or longer that localizes to the anatomic pelvis and is severe enough to cause functional disability and require medical or surgical treatment. Most authorities agree that patients should be diagnosed with CPP if they have pain primarily located in the pelvis for more than 3 or 6 months duration.

Patient history is important in cases of CPP. Because of the complex etiology and, often, the presence of associated disorders, a general approach with a thorough history that directs further evaluation and appropriate consultations is needed. Perform a detailed review of systems, including reproductive, gastrointestinal, musculoskeletal, urologic, and neuro-psychiatric. As needed, ask specific questions, especially if the patient has an associated disorder. A thorough past history also is important to avoid repeating invasive and expensive procedures.

… Focus history on characterizing the patientís pain, which can lead to appropriate diagnostic and therapeutic plans.

° Location of pain: The location of pain is an important part of the history. Ask the patient to describe the pain location and type on a pain diagram (anteroposterior and lateral view of human picture).

° Precipitating factors: Ask questions about factors that provoke or intensify pain. This may provide clues for possible etiologies or associated disorders. For example, in pelvic congestion syndrome, pain is related to posture and is worse at the end of day. In endometriosis, pain commonly is reported during or after intercourse.

° Alleviating factors: Alleviating factors may exist. For example, rest may decrease pain of musculoskeletal or adnexal origin.

° Quality of pain: Various terms can be used to describe the quality of pain. Such terms include throbbing, pounding, shooting, pricking, boring, stabbing, lancinating, sharp cutting, lacerating, pressing, cramping, crushing, pulling, pinching, stinging, burning, splitting, penetrating, piercing, squeezing, and dull aching.

° Pain distribution: Spreading or radiation of pain also is important in the evaluation of neuropathic pain.

° Severity or intensity of pain: Use some type of rating system to evaluate pain severity or intensity with a degree of objectivity and reproducibility. Different types of pain scales may be used. Numerical scales are more useful and reliable. The visual analog scale is one of the commonly used numerical scales.

… Obtain a history specific to different systems and disorders.

° Gynecologic and obstetric: For example, excessive bleeding with menses suggests uterine leiomyomas or adenomyosis. History of previous surgery may suggest intra-abdominal or pelvic adhesions. Patients with cervical stenosis usually have a history of chronic cervical infection or treatment with cryosurgery/laser surgery/loop excision or endometrial resection. Having multiple sexual partners is a risk factor for pelvic inflammatory disease.

° Urologic: A detailed history to evaluate the urological system is important. For example, as compared to patients with pelvic pain, patients with interstitial cystitis report urgency and increased frequency of urination as the most distressing features.

° Gastrointestinal: For example, deflecting sigmoid adhesions are common in women with CPP and frequently are associated with gastrointestinal symptoms.

° Musculoskeletal: History of vaginal delivery with prolonged second-stage episiotomies or tears may suggest pelvic floor relaxation disorder.

° Neurologic: Constant burning pain is a common complaint in patients with pudendal neuralgia. Patients may report dysesthesia and vulvodynia but usually not dyspareunia.

° Psychologic: A good psychosocial or psychosexual history is needed when organic diseases are excluded or coexisting psychiatric disorders are suggested. Obtain sufficient history to evaluate depression, anxiety disorder, somatization, physical or sexual abuse, drug abuse or dependence, and family problems, marital problems, or sexual problems. Sexual abuse occurring before age 15 years is associated with later development of CPP (Lampe, 2000). Somatization is a common associated psychologic disorder in women with CPP. Somatization scales can be used for evaluation.

Physical: Good rapport, tolerance, and an open-minded approach are important in the evaluation of any patient with chronic pain. A thorough systematic examination usually suggests an appropriate diagnosis and therapy.

… Obstetric-gynecologic and other system examinations could be long and stressful. Detailed examination of obstetric-gynecologic and other systems can be performed in different positions. Usually, this includes standing, sitting, supine, and lithotomy positions.

… Lithotomy examination usually includes the following:

° Visual inspection of the external genitalia

° Basic sensory testing and evaluation for trigger points

ß A cotton-tipped swab can be used for precise sensory and tender-point evaluation of the vestibule, vaginal cuff, cervical os, paracervical region, and cervical region.

ß Single-digit examinations of the vulva, pubic arch, levator ani coccyx, introitus, urethral, trigonal, cervix, paracervical areas, vaginal fornices, uterus, and adnexa are indicated.

° Colposcopic evaluation of the vulva and vestibule

° Sims retractor or single-blade speculum examination of the vagina and pelvic muscles

° Bimanual pelvic examination

° Rectovaginal examination

… Perform detailed examinations for other systems (e.g., gastrointestinal, urologic, neurologic, musculoskeletal) as required. For example, gait and posture evaluation, spine examination, and sensory and motor examination often are useful.

° Betty maneuver (for piriformis syndrome): When abduction of the thigh against resistance is requested, the patient will report pain.

° Obturator sign (dysfunction of the obturator muscles or fascia)

° Straight-leg raising test (possible herniated disc, radiculopathy)

° Psoas sign: If pain is elicited during flexion of hip against resistance, this may suggest dysfunction of the psoas muscles or fascia.

° Patrick or faber (flexion in abduction and external rotation) test for hip evaluation

Causes: Various reproductive, gastrointestinal, urologic, and neuromuscular disorders may cause or contribute to CPP. Sometimes, multiple contributing factors may exist in a single patient.

… Extrauterine reproductive disorders

° Endometriosis

° Adhesions

° Adnexal cysts

° Chronic ectopic pregnancy

° Chlamydial endometritis or salpingitis

° Endosalpingiosis

° Ovarian retention syndrome (residual ovary syndrome)

° Ovarian remnant syndrome

° Ovarian dystrophy or ovulatory pain

° Pelvic congestion syndrome

° Postoperative peritoneal cysts

° Residual accessory ovary

° Subacute salpingo-oophoritis

° Tuberculous salpingitis

… Uterine reproductive disorders

° Adenomyosis

° Chronic endometritis

° Atypical dysmenorrhea or ovulatory pain

° Cervical stenosis

° Endometrial or cervical polyps

° Leiomyomata

° Symptomatic pelvic relaxation (genital prolapse)

° Intrauterine contraceptive device

… Urologic disorders

° Bladder neoplasm

° Chronic urinary tract infection

° Interstitial cystitis

° Radiation cystitis

° Recurrent cystitis

° Recurrent urethritis

° Urolithiasis

° Uninhibited bladder contractions (detrusor-sphincter dyssynergia)

° Urethral diverticulum

° Chronic urethral syndrome

° Urethral caruncle

… Musculoskeletal disorders

° Abdominal wall myofascial pain (trigger points)

° Compression fracture of lumbar vertebrae

° Faulty or poor posture

° Fibromyalgia

° Mechanical low back pain

° Chronic coccygeal pain

° Muscular strains and sprains

° Pelvic floor myalgia (levator ani spasm)

° Piriformis syndrome

° Rectus tendon strain

° Hernias (e.g., obturator, sciatic, inguinal, femoral, spigelian, perineal, umbilical)

… Gastrointestinal disorders

° Carcinoma of the colon

° Chronic intermittent bowel obstruction

° Colitis

° Chronic constipation

° Diverticular disease

° Inflammatory bowel disease

° Irritable bowel syndrome

… Neurologic disorders

° Neuralgia/cutaneous nerve entrapment (surgical scar in the lower part of the abdomen; usually iliohypogastric, ilioinguinal, genitofemoral, and lateral femoral cutaneous nerves)

° Shingles (herpes zoster infection)

° Degenerative joint disease

° Disk herniation

° Spondylosis

° Abdominal epilepsy

° Abdominal migraine

° Neoplasia of spinal cord or sacral nerve

… Psychologic and other disorders

° Personality disorders

° Depression

° Sleep disorders

° Sexual and/or physical abuse

… Common causes of CPP in men

° Chronic (nonbacterial) prostatitis

° Chronic orchalgia

° Prostatodynia

Other Problems to be considered:

Reproductive system
Adenomyosis
Adhesions
Adnexal tumors
Cervical stenosis
Dyspareunia
Endocervical and endometrial polyps
Endometriosis and endosalpingiosis
Uterine leiomyomas
Ovarian retention syndrome
Ovarian remnant syndrome
Pelvic varicosities and pelvic congestion syndrome
Vulvodynia
Pelvic floor relaxation disorders
Accessory and supernumerary ovaries

Urinary system
Chronic and recurrent urinary tract infections
Urolithiasis
Pelvic floor dysfunction
Urethral diverticula
Chronic urethral syndrome

Gastrointestinal system
Chronic intermittent bowel obstruction
Colitis
Chronic constipation
Diverticular disease
Inflammatory bowel disease
Irritable bowel syndrome
Peritoneal abscess

Other diseases
Hernias (e.g., obturator, sciatic, inguinal, femoral, perineal, spigelian, umbilical)
Neoplasia of the spinal cord or sacral nerves
Mononeuropathy and nerve entrapment
Abdominal epilepsy
Abdominal migraines
Pelvic floor pain syndrome
Rectus abdominis pain
Faulty posture
Bipolar affective disorder and depression
Chronic visceral pain syndrome
Chronic fatigue syndrome
Substance abuse

Lab Studies:

… The decision to perform laboratory or imaging evaluations is based on the need for confirmation of the diagnosis and to help rule out other potentially life-threatening illnesses. Certain investigations sometimes are needed to provide appropriate and safe medical or surgical treatment.

… Complete blood cell count and sedimentation rate: These tests provide nonspecific findings, but the results can be sensitive indicators of inflammation or infection and, occasionally, malignancy.

… Serum drug screen: Perform this if any suggestion of prescription or street drug abuse is present.

… Urine test

° Urinalysis and urine culture are relatively inexpensive and noninvasive and should be performed when necessary.

° If hematuria is present, carefully evaluate the condition with a history, physical examination, urine culture, urine cytology, cystourethroscopy, and intravenous pyelography or CT scan.

° If malignancy is suggested, perform urine cytology in addition to urinalysis and culture, especially if the patient smokes.

… Sexually transmitted disease testing

° Testing for sexually transmitted diseases in women with CPP includes cervical cultures or smears, syphilis serology (rapid plasma reagent, microhemagglutination - Treponema pallidum), hepatitis B screening, chlamydial polymerase chain reaction, and HIV testing.

° Other tests used to help rule out specific infections may include vaginal cultures, vaginal wet preparations, vaginal pH, and urine analysis and culture.

… Hormone assays: Follicle-stimulating hormone level, estradiol level, and gonadotropin-releasing hormone agonist stimulation testing can be helpful in cases of ovarian remnant syndrome.

… Thyroid-stimulating hormone testing

° This is used for evaluation of hypothyroidism, especially in a patient with depression.

° Perform stool guaiac testing in patients with gastrointestinal symptoms and in patients older than 50 years. Testing stool specimens for ova and parasites also may be helpful in selected cases.

Imaging Studies:

… Magnetic resonance imaging

° MRI is a noninvasive tool that can provide excellent structural information without any radiation harm.

° Intravenous contrast can be used when inflammation, infection, or malignancy is suggested.

… CT scan: This is useful in patients with pelvic masses and sometimes is helpful in differentiating an ovarian mass from a uterine mass, but it is more expensive than sonography.

… Ultrasonography

° This is a noninvasive diagnostic tool and could be helpful in many patients with CPP.

° It commonly is used to help identify pelvic masses or cysts and their origin, pelvic varicosities, and hernias (spigelian hernias).

… Plain film radiography

° Obtaining chest and spine x-ray films may be useful in fractures, infections, tumors, and other structural abnormalities.

° Flat and upright abdominal radiographs may be obtained to help rule out intestinal obstruction and pelvic infection (e.g., tuberculosis).

… Herniography (perineal hernia herniography)

… Bone scan

… Hysterosalpingography

° Hysterosalpingography (HSG) is not a first-choice diagnostic tool for endometriosis; however, it may be useful in patients with infiltrative endometriosis of the uterosacral ligaments. Adolescents with endometriosis also can be evaluated for obstructive anomalies.

° HSG may be useful in cases suggestive of endometrial polyps, Asherman syndrome, and adenomyosis.

… Barium enema radiography, colonoscopy, sigmoidoscopy, upper gastrointestinal series, and anorectal manometry

° These can be used to evaluate a gastrointestinal etiology of chronic pain.

° Anorectal balloon manometry can be used to assess colonic transit time.

… Vaginal sonography

° This is useful in patients with possible pelvic congestion syndrome.

° Transuterine venography commonly is recommended.

… Voiding cystourethrography: When interstitial cystitis is suggested, consider cystoscopy with hydrodistention.

… Double-balloon cystourethrography: This is a more sensitive diagnostic test than voiding cystourethrography for diagnosing urethral diverticula in women (Jacoby, 1999).

Other Tests:

… Endoscopic procedures used commonly in the evaluation and treatment of patients with CPP include laparoscopy, cystourethroscopy, hysteroscopy, sigmoidoscopy, and colonoscopy.

… Laparoscopy can be used as a diagnostic tool in patients with CPP, as follows:

° More than 40% of laparoscopies are performed for the diagnosis of CPP.

° More then 60% of women with CPP have at least one condition detectable by laparoscopy.

° Most commonly, diagnoses made via laparoscopy include endometriosis, pelvic adhesions, and chronic pelvic inflammatory disease. Other diagnoses include ovarian cysts, hernias, pelvic congestion syndrome, ovarian remnant syndrome, ovarian retention syndrome, postoperative peritoneal cysts, and endosalpingiosis.

… Urodynamic testing can be performed if chronic urethral syndrome or interstitial cystitis is suggested in a patient with CPP.

… Nerve-conducting velocities and needle-electromyographic studies are used to help evaluate compression or entrapment neuropathy and pelvic floor function.

… Cancer antigen 125 (CA125), used as a diagnostic test, has low sensitivity and specificity.

° CA125 may be elevated with diseases associated with pelvic pain, such as endometriosis or leiomyomata.

° CA125 levels also are elevated with malignancy (e.g., ovarian, endometrial, colon, or breast cancer), pelvic inflammatory disease, pregnancy, and menses (Howard and Perry, 2000).

° Perform electroencephalography if the rare disorder of abdominal epilepsy is suggested.

Medical Care: Treatment of pelvic pain is complex in patients with multiple problems. It usually requires specific treatment and simultaneous psychological and physical therapy. A good relationship should be established between the physician and the patient. Treatment of CPP must be tailored for the individual patient.

The goals of treatment must be realistic. They should be focused toward restoration of normal function (minimal disability), better quality of life, and prevention of relapse of chronic symptoms.

… Pharmacotherapy

° Pharmacotherapy consists of symptomatic abortive therapy to stop or reduce the severity of the acute exacerbations and long-term therapy for chronic pain.

° Initially, pain may respond to simple over-the-counter (OTC) analgesics such as paracetamol, ibuprofen, aspirin, or naproxen. If treatment results are unsatisfactory, the addition of other modalities or the use of prescription drugs is recommended.

° If possible, avoid use of barbiturate or opiate agonists. Also discourage long-term use and overuse of all symptomatic analgesics because of the risk of dependence and abuse.

° Tizanidine may improve the inhibitory function in the central nervous system and can provide pain relief. Therapy with tizanidine is not considered the standard of care

° Amitriptyline (Elavil) and nortriptyline (Pamelor) are the tricyclic antidepressants (TCAs) used most frequently for chronic pain.

° The selective serotonin reuptake inhibitors (SSRIs) fluoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft) also are prescribed commonly by many physicians. Other antidepressants such as doxepin, desipramine protriptyline, and buspirone also can be used.

… Physical therapy

° Physical therapy techniques include hot or cold applications, positioning, stretching exercises, traction, massage, ultrasound therapy, transcutaneous electrical nerve stimulation (TENS), and manipulations. Heat, massage, and stretching can be used to alleviate excess muscle contraction and pain.

° Pelvic floor training also may be recommended.

… Psychophysiological therapy

° Psychophysiological therapy includes reassurance, counseling, relaxation therapy, a stress management program, and biofeedback techniques. With these modalities of treatment, both frequency and severity of chronic pain may be reduced.

° Biofeedback may be helpful in some patients when combined with medications.

Surgical Care:

… Various minimally invasive techniques may provide pain relief. These techniques include the following:

° Trigger point injections: These injections are used mostly for localized trigger points (myofascial pain or neuroma).

° Peripheral nerve blocks: Specific peripheral nerve block with local anesthetic and steroids may be helpful in selected cases.

… Neuroablation of selected nerves can be performed by using different techniques, including thermocoagulation (radiofrequency ablation), cryoablation, or injection of chemical agents (alcohol, hypertonic saline, phenol).

° An intrathecal morphine pump may be used, but careful selection for appropriate patients is very important.

° Sacral nerve stimulation may be effective in the treatment of therapy-resistant pelvic pain syndromes linked to pelvic floor dysfunction (Everaert, 2001).

… Various surgical procedures may be considered to treat CPP. Surgical procedures include presacral neurectomy (superior hypogastric plexus excision), paracervical denervation (laparoscopic uterine nerve ablation), and uterovaginal ganglion excision (inferior hypogastric plexus excision).

Consultations: Consultation with a psychologist, urologist, neurologist, and gastrointestinal specialist or other appropriate specialists is very important, especially before considering invasive or aggressive management.

Further Inpatient Care:

… Hospitalization usually is not required for patients with CPP; however, the need for hospitalization depends on the invasiveness of the treatment choice for pain control and on the severity of the case.

Further Outpatient Care:

… Patients with CPP generally are treated in an outpatient setting and require a variety of health care professionals to optimally manage their condition.

Complications:

… Like other chronic pain, CPP may lead to prolonged suffering, marital or family problems, loss of employment, disability, and various adverse medical reactions from lifelong therapy.

Patient Education:

… The patient and the patientís family should have a good understanding about the multifactorial nature of chronic pain. They need multidisciplinary and comprehensive management plans.

… Instruct the patient to avoid uncomfortable stressful positions and bad posture. Also recommend regular exercise, good sleeping habits, and balanced meals.

… Try biofeedback and relaxation techniques.

Medical/Legal Pitfalls:

… Good rapport, tolerance, and an open-minded approach are important in the evaluation of any patient with chronic pain.

… Patients with CPP may exhibit exaggerated pain behavior or sensations that seem to be hysterical or appear nonanatomic or nonphysiologic; however, these patients always must be taken seriously and appropriate conservative steps should be taken.

… Obtaining a thorough past history is important to avoid repeating invasive and expensive procedures.

… Consultation with a psychologist, urologist, neurologist, and gastrointestinal specialist or other appropriate specialists is very important, especially before considering invasive or aggressive management.

Special Concerns:

… Appropriate caution must be taken during treatment of patients with the following characteristics:

° Poor response to prior appropriate treatment

° Unusual unexpected response to prior specific treatment

° Avoidance of school, work, or other social responsibilities

° Severe depression

° Severe anxiety disorder

° Excessive pain behavior

° Frequent physician changes

° Noncompliance with past treatment

° Drug abuse or dependence

° Family, marital, or sexual problems

° History of physical or sexual abuse

… Pregnancy

° The use of medication during pregnancy is not contraindicated, but it should be limited and carefully justified.

° Initially, pain should be managed with nonpharmacologic measures such as reassurance, rest, hot or cold applications, positioning, stretching exercises, massage, ultrasound therapy, TENS, relaxation therapy, and biofeedback. If pain does not respond to a nonpharmacologic approach, symptomatic drugs may be used carefully.

° Acetaminophen and codeine (alone or in combination) can be used during pregnancy.

° Nonsteroidal anti-inflammatory drugs such as ibuprofen and aspirin may be considered during the first trimester of pregnancy, but they should be avoided especially during the last trimester. They may constrict or close the fetal ductus arteriosus and may cause maternal and fetal bleeding.

° Limit benzodiazepine and barbiturate use. Do not use ergotamine, dihydroergotamine, and sumatriptan.

… CPP in men: Chronic (nonbacterial) prostatitis, chronic orchalgia, and prostatodynia are common causes of CPP in men of any age.

NEUROGENIC PELVIC PAIN

Chronic pelvic pain is more common in women but has also been reported in men. Overall, a woman has about a 5% risk of having chronic pelvic pain in her lifetime. In women with a previous diagnosis of pelvic inflammatory disease, this risk is increased fourfold. Recent epidemiologic data from the United States showed that 14.7% of women in their reproductive ages reported chronic pelvic pain. An estimated 9.2 million people suffer from chronic pelvic pain in the United States alone, and estimated medical costs for outpatient treatments in the United States are $881.5 million per year. The personal cost to the affected patient in terms of years of suffering, disability, marital discord, loss of employment, and unsuccessful medical intervention can be calculated less easily. Patients with chronic pelvic pain are usually evaluated by several physicians from different subspecialties, including gynecologists, gastroenterologists, urologists, and internists. Neurologists are consulted to help rule out neurogenic causes of chronic pelvic pain and to assist with pain management. When patients present with chronic pelvic pain, the main focus is typically on identifying and possibly treating the underlying pelvic disease. Despite many diagnostic tests and procedures, the diagnostic workup often remains unrevealing and no specific cause of the pain can be identified. At this point, patients are frequently told that no cause for their chronic pain syndrome can be found and that nothing can be done. Some patients are referred for evaluation of an underlying psychologic reason because no ëëorganic causeíí of the disease has been identified. Although these patients are often depressed, rarely are these chronic pelvic pain syndromes the only manifestation of a psychiatric disease. In these cases, pain is not only a symptom of pelvic disease, but the patient is suffering from a chronic pelvic pain syndromeóëëa state of pelvic hypersensitivityíí in which pain is the prominent symptom of the chronic visceral pain syndrome. Once the diagnosis of chronic pelvic pain is made, treatment should be directed toward symptomatic pain management. This conceptualization of chronic pelvic pain is very important because chronic pelvic pain is a treatable condition. Despite the challenge inherent in the management of chronic pelvic pain, many patients can be treated successfully using a multidisciplinary pain management approach, whereby the neurologist can play an important role.

DEFINITION

At present, one of the major problems in the field of chronic pelvic pain (and chronic visceral pain in general) is the lack of agreed-on definitions, which would allow comparisons

between clinical case reports and clinical studies. In the gynecologic literature, a definition of chronic pelvic pain as ëënoncyclic pelvic pain of greater than 6 monthsí duration which is not relieved by nonnarcotic analgesicsíí had been proposed. The definition of chronic pelvic pain in relation to the response to analgesic treatment is, however, very problematic: Would a patient with chronic pelvic pain who responds to opioids be diagnosed with chronic pelvic pain, but the patient who responds to tricyclic antidepressants, not? The International Association for the Study of Pain defines chronic pelvic pain without obvious pathologic factors as chronic or recurrent pelvic pain that apparently has a gynecologic origin but for which no definitive lesion or cause is found. This definition is problematic because (1) it implies absence of pathologic source, which is not necessarily the case, and (2) it also excludes cases in which a pathologic factor is present but not necessarily the cause of pain. In fact, the relationship of pain to the presence of pathologic findings is often unclear in patients with chronic pelvic pain, and this definition has not been widely used in the literature. In this chapter, chronic pelvic pain refers to pelvic pain in the same location for at least 6 months (ACOG Technical Bulletin, Int J Gynecol Obstet, 1996). This broad definition acknowledges that many chronic pain states may begin with a nociceptive process although that event might go unrecognized or unremembered.

NEUROBIOLOGIC ASPECTS OF CHRONIC PELVIC PAIN: A CHRONIC VISCERAL PAIN SYNDROME

In the clinical context, neurologists must have a basic understanding of the key features of the neurobiology of chronic pelvic pain to shed some light on these often confusing clinical presentations, to make a diagnosis of chronic pelvic pain, and to look at the global picture of pelvic dysfunction, rather than ëëchasingíí one aspect of the chronic pain syndrome out of context. The visceral structures that may give rise to pain in the pelvic region belong to the genitourinary system, the gastrointestinal system, and the associated pelvic vasculature and lymphatic structures. The pelvis is innervated by both divisions of the autonomic nervous system, the sympathetic and parasympathetic divisions, as well as by the somatic and sensory nervous systems. Dual projections from the thoracolumbar and sacral segments of the spinal cord carry this innervation, converging primarily into discrete peripheral neuronal plexuses before distributing nerve fibers throughout the pelvis. The visceral afferents traveling in the sympathetic trunk have cell bodies in the thoracolumbar distribution, and those that travel with the parasympathetic fibers have cell bodies in the sacral dorsal root ganglia. Both visceral sensory pathways play a role in pelvic sensations and reflexes. The inferior hypogastric plexus is the major autonomic neuronal relay center in the pelvic cavity, integrating the sympathetic and parasympathetic outflow. The dorsal root ganglion cells at the thoracolumbar and sacral level are the first of numerous relays of sensory neurons that transmit painful sensations from the pelvic cavity to the brain. Ascending visceral spinal pathways include the spinothalamic Pain and spinoreticular tract and the dorsal column pathway. Somatic neuronal outflow to the pelvis is represented by the sacral nerve roots, which form the sacral plexus, through which the pudendal nerves diverge, carrying efferent and afferent innervation and postganglionic axons from the caudal sympathetic chain. Sensations from the pelvic viscera are mainly conveyed within the sacral parasympathetic sys- tem, with the sympathetic thoracolumbar system contributing far less. Pelvic pain is a subgroup of visceral pain (other examples are cardiac pain, abdominal pain, etc.). For the neurologist assessing a patient with chronic pelvic pain, it is important to recall the typical features of visceral pain, because this will help to elucidate the otherwise quite confusing clinical presentation: visceral pain is a diffuse sensation that cannot be precisely localized. Pain in one viscus cannot be easily differentiated from pain originating in another viscus, which often makes the differential diagnosis very complicated. Some patients present with ëëmore than one pelvic pain (i.e., dysmenorrhea and irritable bowel syndrome).íí Given the extensive convergence of visceral afferent input on the level of the spinal cord and in the periphery (plexuses), it would not be surprising if a chronic pain syndrome in one area of the pelvis would trigger the development of pain and dysfunction in another area of the pelvic cavity. In addition, visceral pain presents with two componentsótrue visceral pain, which is pain deep in the pelvic cavity, and referred visceral pain to somatic structures (muscle and skin) and other visceral structures with overlapping spinal cord representation. Secondary hyperalgesia usually develops at the referred site. When examining and treating a patient with pelvic pain, consideration must be given to all these aspects of visceral pain. The muscular component (referred pain) of pelvic pain can be so striking that the chronic pelvic pain syndrome may be confused with back pain. The patient should be asked about all components of the pain. A treatment strategy might have a positive effect on one component of the pain, while the other component persists, requiring additional treatment.

PSYCHOLOGIC ASPECTS OF CHRONIC PELVIC PAIN

Although psychologic research on aspects such as depression, anxiety, and a history of physical or sexual abuse has been conducted on chronic pelvic pain, several results are hampered by lack of appropriate control groups using pain patients, small sample size, and samples without significant self-selection factors. Many studies have neglected to examine whether the psychologic findings were likely to be preexisting or reactive; therefore it is not possible to draw conclusions about the role of these factors in the cause of the complaint. Although the traditional psychosocial view of pain disorders specifically of the pelvic and urogenital region has focused on sexual and marital issues, conflicts, and experiences and has tried to dichotomize the cause between psychologic and physiologic factors, a pain-centered approach focusing on the major symptom of these problems, the pain, has been suggested in the recent psychologic literature.

CLINICAL CHARACTERISTICS AND DIFFERENTIAL DIAGNOSIS

Patients with chronic pelvic pain complain about deep pain in the pelvis that is unilateral, bilateral, or in the midline and often radiating to the low back, anterior abdominal wall, buttocks, hips, perineal area, and anterior thighs. Associated symptoms may include changes in bowel and urinary habits, changes in sexual function, and pain in the urogenital and pelvic area associated with sexual activity. The pain syndrome can be exacerbated by postural changes, such as walking. Pelvic pain can be cyclic (related to the menstrual cycle in women), intermittent, or continuous. Although chronic pelvic pain is usually thought to be primarily of gynecologic origin, all other structures in the pelvic cavity, including the urinary tract, the lower gastrointestinal tract, and pelvic blood vessels, the musculoskeletal system, and neurologic and psychiatric causes have to beincluded in the differential diagnosis. Recurrent severe pelvic pain with pain-free intervals in between is often due to metabolic causes, familial Mediterranean fever, porphyria, or C1 esterase deficiency associated with angioneurotic edema. A rare cause of severe chronic recurrent pelvic pain is tabes dorsalis. Thus the differential diagnosis is complex and requires the concerted effort of health care providers of several medical subspecialties (Table 1). Localization of the source of pain is often inaccurate or difficult to determine both for the patient and for the physician because of the overlapping innervation pattern of the pelvic organs. Given the extensive convergence of visceral afferent input on the spinal cord level and in the neuronal plexuses in the pelvis demonstrated in animal studies, it is not surprising that some patients initially have chronic pain that seems to be related to one pelvic organ and then have pain and dysfunction extending to other pelvic areas. Even a thorough history and physical examination often do not allow a cause for the chronic pain syndrome to be identified. Fewer than 50% of patients are helped by diagnostic or therapeutic laparoscopy, suggesting that laparoscopy is not the ultimate investigation. The relationship of pelvic pain to pathologic source is not clear. A patient may have significant adhesions or endometriosis with little or no pain; in contrast, another patient might have severe pain but minimal or no pelvic pathologic findings that can be assessed with currently available diagnostic techniques. The workup of the patient with chronic pelvic pain starts with a thorough medical history focusing on the intensity, character, temporal pattern, duration, location, and radiation of the pain, as well as precipitating and relieving factors. Specific attention is paid to associated changes in bowel, urinary, and sexual function. A review of systems should also include neurologic and musculoskeletal functions and the influence of the chronic pelvic pain syndrome on mood and on functions in various aspects of the patientís life (personal life, family life, workplace, sexual life). The physical evaluation is focused on the area of pain and includes a general physical, neurologic, musculoskeletal, and pelvic examination. Procedures during the physical examination that provoke or exacerbate the pelvic pain are carefully noted. Areas of hyperalgesia and trigger points are documented. Consultations with other specialists in gynecology, gastroenterology, urology, and orthopedics and further diagnostic evaluations might be indicated. A difficult decision is determining when to stop looking further for a macroscopic abnormality that could account for the chronic pelvic pain syndrome and when to stop treating a pelvic pathologic condition if the treatment is not resulting in pain relief (implying that the pathologic condition identified is not related to the chronic pelvic pain problem). This decision is often avoided by health care providers and patients for fear of overlooking something. It is important to call a halt to investigation once it is clearly negative. This caveat must be raised especially for invasive diagnostic procedures in which the risk to the patient might be greater than the likelihood of discovering something new.

Table 1 Differential Diagnosis of Chronic Pelvic Pain

Gynecologic (extrauterine, uterine)

Urologic

Gastrointestinal

Musculoskeletal

Neurologic

Psychiatric

Referred pain to the pelvis (from thorax, spine, or pelvic floor)

Familial Mediterranean fever

Porphyria

C1 esterase deficiency (associated with angioneurotic edema)

Neurosyphilis

TREATMENT

After a thorough diagnostic workup has been completed, the first step is to determine if any underlying causes of chronic pelvic pain can be treated directly. Typically there are three scenarios: (1) the cause of the chronic pelvic pain is identified and treated, with resolution; (2) the cause of the chronic pelvic pain is identified and treated, but the pain does not resolve, which implies that the pain is unrelated to the identified pathologic condition or that the pathologic finding initiated a chronic pain syndrome that persists despite ëëcureíí of the initial noxious stimulus that triggered it; or (3) no ëëpathologic conditioníí that could explain the symptoms can be identified with current diagnostic techniques. In the latter two cases a symptomatic pain treatment plan is established. Outcome measures for the treatment of chronic pelvic pain include a reduction of pain intensity in the pelvic cavity and in the referred zone; improvement of associated changes in bowel, urinary, and sexual function; improved mood; and improvement of the functional status of the patient in his/her personal life, family life, workplace, and sexual life. Different outcome measures have different importance for individual patients, and this aspect is important to discuss as a treatment plan is established. Treatment has to be tailored to the individual patient. For example, a patient with chronic pelvic pain characterized by severe referred pain to the back and the urogenital floor might benefit from physical therapy early on in the treatment plan. In a woman with chronic pelvic pain who is of reproductive age and who is planning to become pregnant, pharmacologic treatments for chronic pain have to be carefully considered because some might be contraindicated during pregnancy. In such a patient, nonpharmacologic treatment avenues such as transcutaneous electrical nerve stimulation (TENS) or acupuncture might be considered first. In the following text, treatments for chronic pelvic pain that can be applied or prescribed by the neurologist and treatments that require the expertise of other medical specialties are discussed. A multidisciplinary approach is often required, in which neurologists can play an important role, and a basic understanding of the expertise that other medical subspecialties can offer for the treatment of chronic pelvic pain is important for a successful multidisciplinary collaboration as well.

Surgery for Chronic Pelvic Pain

In the past, surgical approaches toward the treatment of chronic pelvic pain have been very common. Failure of achieving pain relief after surgical procedures has often resulted in more aggressive surgical efforts, driven by the hypothesis that the surgically curable lesion might have been missed earlier. However, the gynecologic literature has shown that long term success after surgical procedures is often disappointing when pelvic pain is the only indication for surgery. In these cases, patients probably suffer from a ëëpelvic hypersensitivity,íí and surgery is unlikely to improve the pain, especially when ëëwhat should be operated oníí is unclear. The physician and the patient must have realistic expectations and understand that the chronic pain syndrome may be improved or cured but also may be unchanged or worsened by the procedure.

Pharmacologic Therapy

Very little is known about effective pharmacologic treatment for chronic pelvic pain. Further research on the mechanisms of chronic pelvic painówith the aim of identifying drug targetsóand controlled clinical trials are desperately needed to design improved pharmacologic treatment strategies. Currently available treatment strategies, which have been used for other chronic pain syndromes, can be successfully applied to patients with chronic pelvic pain (Table 2). Several pharmacologic classes of medications have been

shown to decrease pain in patients with chronic pain syndromes, such as nonsteroidal antiinflammatory drugs, anti-depressants, anticonvulsants, local anesthetic antiarrhythmics, and opioids. These medications can also be used to successfully treat patients suffering from chronic pelvic pain. Although clinical trials and case reports on the pharmacologic management of chronic pain syndromes provide general guidelines regarding which drug to choose, no algorithm can predict which drug is most likely to alleviate pain in a given patient. The goal of pharmacotherapy is to find one drug or a combination of drugs that provides significant pain relief with minimal side effects. It is important that the patient is aware of the limitations of this ëëtrial-and-erroríí method of prescribing drugs and has realistic expectations. Adequate trials should be performed for each drug prescribed, and only one drug should be titrated at a time (otherwise the effects of a certain drug on pain scores cannot be assessed). Different medications can have different and selective effects on certain aspects of pain (deep pain in the pelvis, referred pain, hyperalgesia in the referred zone), and the effects on each aspect of pain must be carefully monitored. The starting dose should always be the smallest dose available, and titration should occur at frequent intervals guided by pain scores and side effects. This approach requires frequent contact between the patient and health care provider during the titration period. Some side effects might improve over time. If these side effects are not intolerable, the patient should be guided through this period. Common reasons for failure are inadequate titration to an adequate dose of medication and early termination of treatment as a result of side effects produced by increasing the dose too rapidly; starting at a high initial dose, resulting in severe side effects; or starting more than one drug at the same time.

Table 2 Pharmacologic Treatment of Chronic Pelvic Pain

ANTIDEPRESSANTS

Tricyclics

Mixed reuptake inhibitors

Selective serotonin reuptake inhibitors

ANTICONVULSANTS AND ANTIARRHYTHMICS

Sodium channel blockers

Other mechanisms of action

OPIOIDS

Oral long-acting opioids (slow-release opioids, opioids with a long half-life)

Transdermal

Epidural or intrathecal

OTHER AGENTS

Nonsteroidal antiinflammatory drugs

Regional Anesthesia Techniques

Over the last 8 years there has been a renewed interest in neurolytic superior hypogastric plexus blocks for the treatment of chronic pelvic pain associated with cancer. These regional anesthesia techniques have now also been suggested as diagnostic tools and therapeutic interventions for women with chronic nonmalignant pelvic pain. The superior hypogastric plexus innervates the pelvic viscera via the hypogastric nerves. Pain relief following neurolytic blockade of the superior hypogastric plexus might be due to interruption of the afferent pathways from the pelvic organs or interruption of the sympathetic outflow to the pelvic organs, similar to sympathetically maintained pain syndromes. Chronic pelvic pain might be due to entrapment of the ilioinguinal, iliohypogastric, genitofemoral, or pudendal nerves. In these patients the chronic pelvic pain typically developed after previous pelvic surgery, and the pain is described as very focal, radiating to the abdominal wall, groin, or perineal area. These pain syndromes can often be managed by repeated local anesthetic nerve blocks to these nerves, spaced out over time.

Transcutaneous Electrical Nerve Stimulation

TENS has been shown to be effective in some patients with primary dysmenorrhea and also in patients with noncyclic chronic pelvic pain. In contrast to many other pain treatment strategies, TENS has no side effects.

Acupuncture

Acupuncture has been used for many centuries to control pain. Treatment is empirical in that the exact mechanism of the analgesic effect of acupuncture has not been elucidated yet. Anecdotal reports of acupuncture being used as part of a multidisciplinary treatment approach indicate an effective role for the management of chronic pelvic pain.

Trigger Point Injections

Myofascial pain of the extremities or of the upper trunk has been shown to respond to trigger point injections. Patients with chronic pelvic pain often present with referred pain to somatic structures, including the abdominal wall, back, urogenital floor, and legs. If the referred muscular pain is very focal (ëëtrigger pointsíí), injections of local anesthetics into these trigger points have been reported to result in pain relief.

Physical Therapy Approaches

Because visceral pain is referred to somatic structures, muscle pain in the referred zone is a typical component of chronic pelvic pain. Physical therapy serves two aspects: it helps to decrease musculoskeletal pain, and it improves mobility. Physical therapy is an important aspect of a multidisciplinary approach to the treatment of chronic pelvic pain and usually requires a physical therapist with special expertise of the pelvis and pelvic floor.

Vascular Approaches

As reported in the gynecologic literature, venous congestion can be visualized on imaging studies in some patients with chronic pelvic pain and might be the origin of their pain. Recently transcatheter embolization of lumboovarian varices has been described as a safe technique offering symptomatic relief in selected patients with chronic pelvic pain caused by pelvic congestion.

Neurosurgical Approaches

Pelvic Denervation

Pelvic denervation was often advocated for treating chronic pelvic pain, including dysmenorrhea. These surgical techniques became less popular as medical therapy for pelvic diseases was advancing; however, with the recent widespread use of laparascopic surgery, there has been a new interest in pelvic denervation. The procedures include presacral neurectomy and amputation of the uterosacral ligaments for chronic pelvic pain. The literature is controversial regarding the success of this surgical procedure to relieve chronic pelvic pain. Some suggest that a diagnostic superior hypogastric plexus block might predict the response to a surgical presacral neurectomy. Careful attention to pelvic function (including sensation; motility, such as colonic motility; and sexual function) is necessary to evaluate for possible side effects of surgical pelvic denervation. Impairment of neurologic function of the pelvis resulting from surgical denervation might not be as obvious as in the somatic domain, where transection of a peripheral nerve results in motor and sensory deficits that can easily be observed and quantified. Other alternatives to surgery may include the use of neurolytic superior hypogastric plexus blocks, in patients that responded well to the diagnostic superior hypogastric plexus block, and spinal cord stimulator implants.

Neurogenic Pelvic Pain

Decompression of Entrapped Nerves

If the clinical picture suggests entrapment of a nerve (pudendal nerve, perineal pain; ilioinguinal or iliohypogastric nerve, groin pain; genitofemoral nerve, lower abdominal and perineal pain), surgical neurolysis of entrapped nerves might be indicated. Diagnostic nerve blocks with local anesthetic and electromyographic or nerve conduction velocity studies help to confirm the diagnosis. The determining factor in achieving pain relief with neurolysis seems to be early diagnosis of nerve entrapment. With prolonged nerve entrapment, central changes might take place, so the later release of the entrapment may not result in marked pain relief.

Myelotomy

Recently punctate midline myelotomy has been advocated for the relief of malignant pelvic pain based on promising results in a limited number of cancer patients. The aim of this procedure is to disrupt ascending nociceptive signals from the pelvic organs traveling in the medial part of the posterior columns. The preliminary data indicate that significant pain relief can be obtained following punctuate midline myelotomy with minimal neurologic morbidity. As discussed earlier for pelvic denervation, careful evaluation of patients who have undergone this procedure is necessary to assess which other functions this pathway might have, in addition to mediating nociceptive signals from the pelvis, before this irreversible procedure can be considered as one of the treatment options for patients with chronic nonmalignant pelvic pain.

Psychologic Approaches

As in other chronic pain syndromes, psychologic treatment should be part of the treatment plan early on, rather than as a last resort after everything else has failed. Psychologic factors, if not addressed, may influence the success of any treatment modality. Patients who have experienced chronic pelvic pain for years often are impatient and anxious and have unrealistic expectations about a ëëquick cure.íí Frequently used psychologic techniques include relaxation techniques, biofeedback, psychotherapy, and group therapy.

FUTURE DIRECTIONS

Both the patient and the physician must recognize that chronic pelvic pain syndromes, a subgroup of chronic visceral pain, do exist and are quite common. The neurologist can play an important role in the multidisciplinary management of these patients. There seem to be multiple barriers to the treatment for patients with chronic neurogenic pelvic pain, perhaps more than in any other area of neurology and chronic pain. These barriers must be recognized to overcome them. First, the subjective symptom of pain in patients with chronic pelvic pain, in a clinical presentation where a cause often cannot be identified, is commonly viewed with skepticism: there is no ëëlegitimateíí reason for the pain. Recognizing that chronic pelvic pain presents with the typical features of chronic visceral pain, and thus placing this chronic pain syndrome into context with other chronic visceral pain syndromes, will hopefully have an important impact. Second, the differential diagnosis of chronic pelvic pain is usually quite complex because the symptoms are often diffuse and not specific. When treating patients with chronic pelvic pain, the physician requires more intellectual and emotional resources, both to consider other treatment options and to overcome emotional reactions that could block more lateral or creative thinking. Further education at the graduate and postgraduate level is urgently needed to overcome this barrier, which is due to a lack of knowledge. Finally, chronic pelvic pain has a direct impact on the sexual life of the patient. In addition, the area of the body where the pain is experienced is often considered taboo. Both the patient and the health care provider may feel uncomfortable discussing pain of the pelvis.