Chapter 35. Pelvic Pain

Pelvic pain is a complicated topic and a clinical challenge, because the very definition of this pain can vary. The pelvis has a formal anatomic description; however, pelvic pain can refer to pain experienced in the general pelvic cavity or pain that is synonymous with gynecologic pain. In addition, gynecologic pelvic pain, although potentially acute or chronic, can refer to chronic pain with or without an anatomic lesion. Under these circumstances the parameters for describing pelvic pain also fluctuate. In the most general context, pelvic pain can be visceral, somatic, and neuropathic. Causal categories are traumatic, mechanical, and psychological. Organ systems include the genitourinary, gastrointestinal, neurologic, and musculoskeletal. The treatment of pelvic pain encompasses not only discoveries in clinical physiology and pharmacology, but also the social and intellectual assumptions behind the clinical practice.

It is estimated that 9.2 million women in United States have pelvic pain. Ten percent of all gynecologic office visits are for pelvic pain; 44% of all laparoscopies and 10% to 15% of hysterectomies are for chronic pelvic pain; and 30% of women presenting to a pain clinic have already undergone hysterectomy. The male pelvic pain syndrome comprises of 8% of all urologic visits and 1% of all visits to primary care physicians. The economic impact is enormous, with medical costs of $1.2 billion per year and missed work and productivity totalling $15 billion per year.

Any discussion of pelvic pain requires an appreciation of the spatial relations of the pelvic viscera, along with their vascular supply and innervation. The pelvis has as its walls the bony pelvis and as its floor the pelvic diaphragm. It is lined by a complex vascular structure and traversed by sympathetic and parasympathetic afferent, visceral afferent, and efferent nerves from the lumbar and sacral plexes. The pelvis is divided into a major pelvis and a minor pelvis, separated by the pelvic brim, which also is the boundary between the abdominal and pelvic cavities. The pelvis contains the bladder and the paravesical fossae in front, the rectum and the pararectal fossae in back, and the internal genital organs in the middle.

The bony pelvis includes two hip bones formed from the fusion of the ischium, ilium and pubis, the sacrum, and coccyx. The two innominate bones form the sides of the pelvis. They are joined in front at the symphysis pubis and articulate with the sacrum and coccyx in back.

The pelvic diaphragm, or floor of the pelvis, arises in front from the body of the pubis and continues behind to the coccyx. It includes the levator ani muscles and the coccygeus muscles. The diaphragm holds the lower part of the rectum and supports the bladder, vagina, and prostate by maintaining sufficient intraabdominal pressure. Beneath the diaphragm is the perineum, with the external genitalia.

Although the bony pelvis can be compared to a basin, the pelvic vasculature resembles a woven lining composed of large, thin-walled veins through which the arteries thread their way. The veins are divided into vesicle, uterine and vaginal or prostatic, and rectal venous plexes, which drain into the internal iliac vein and into the inferior mesenteric veins via the superior rectal (hemorrhoidal) vein, eventually reaching the portal vein. The middle rectal vein emerges from the lower part of the side of the rectum, passes to the internal iliac vein, and anastomoses with the superior and inferior rectal veins and with the other plexes of pelvic veins.

The arteries of the pelvis arise from the internal iliac artery, which runs retroperitoneally, is posterior to the ureter, and is divided into anterior and posterior divisions. The anterior division has seven branches, and the posterior division, three. Collateral circulation is abundant.

The major afferent pathways for nociception from the female pelvic organs travel with the sympathetic nerve bundles and have cell bodies in the thoracolumbar distribution. The suprapubic area is innervated by the iliohypogastric nerve (L1, L2). The inguinal area and the base of scrotum or labia are supplied by the ilioinguinal nerve (L1, L2). The skin of the penis is supplied by the two dorsal nerves of the penis, which are branches of pudendal nerves. The skin of the scrotum and perineal skin are supplied by the posterior scrotal nerves (S2, S3, and S4). The skin between the anus and coccyx is innervated by the lower sacral and coccygeal plexus. The lower third of the vagina is supplied by the pudendal nerve. The genital branch of the genitofemoral nerve supplies the lateral side of the scrotum, the vulva, and the cremasteric muscles.

There are sympathetic, parasympathetic, and visceral somatic afferent nerves to the pelvic viscera. The sympathetic nerves cause muscular contraction and vasoconstriction, whereas the parasympathetic nerves relate to relaxation and vasodilation. Most of the autonomic fibers enter the pelvis through the superior hypogastric plexus, which is located bilaterally at the lower third of the fifth vertebral body and the upper third of the first sacral vertebra at the sacral promontory. This plexus is primarily sympathetic and is formed by the confluence of lumbar sympathetic chains and branches of the aortic plexus containing fibers that traverse the celiac and inferior mesenteric plexus (Fig. 35-1). The superior hypogastric plexus divides into the right and the left hypogastric nerves, which descend laterally to the sigmoid colon to reach the inferior hypogastric plexus.

The inferior hypogastric plexus is located against the inside of the pelvis, lateral to the uterovaginal junction and the rectum. It is the major neuronal integrative center in the pelvis. It innervates multiple pelvic organs, including the urinary bladder, proximal urethra, distal ureter, rectum, and internal anal sphincter, as well as genital and reproductive structures via communication through the uterovaginal plexus and the vesical and the inferior rectal plexus. The parasympathetic nerves, which are branches of anterior rami of the S2, S3, and S4 nerve roots, traverse the inferior hypogastric plexus. In contrast to the superior hypogastric plexus, which is situated predominantly in the longitudinal plane, the inferior hypogastric plexus is oriented more transversely, extending posteroanteriorly and parallel to the pelvic floor. The location and configuration of the inferior hypogastric plexus does not lend itself to surgical or chemical extirpation.

The sensory nerves from the uterus accompany the sympathetic nerves and enter the spinal cord at the T11 and T12 level, and refer pain to the abdomen. The S2, S3, and S4 afferents from the cervix are referred to the lower back and lumbosacral area.1,2

The ganglion impar (also known as ganglion of Walther) is a solitary retroperitoneal structure located at the level of the sacrococcygeal junction that marks the termination of the paired paravertebral chains. This structure receives fibers from the lumbar and sacral portions of the sympathetic and parasympathetic nervous system. It provides sympathetic innervation to portions of the perineum, rectum, and genitalia.

Pelvic pain is often considered synonymous with gynecologic pain. Such pain can be acute or chronic. Acute pain is caused by structural disruption or physiologic dysfunction, whereas chronic pain may be the result of persistent pressure on nerves, inflammation of arteries, diseases of the female reproductive organs, and factors not demonstrable by present-day imaging techniques.

Acute Pain

The differential diagnosis of acute pelvic pain includes ectopic pregnancy and complications of pregnancy, ruptured cysts, ovarian and adnexal torsion, uterine fibroids, and pelvic inflammatory diseases. Ninety-eight percent of women with ectopic pregnancy experience unilateral pain, which may be accompanied by light or missed menses. Symptoms of pregnancy, such as nausea and breast tenderness, also may be present.3

The pain of ovarian cysts may be dull and aching, localized to the side of the abscess, and accompanied by pelvic tenderness. An ovarian cyst with a twisted pedicle can cause acute pain, which becomes intermittent when the pedicle untwists. Other symptoms include nausea and vomiting, diarrhea or constipation, and leukocytosis.

Symptoms of a palpable mass, delayed menses, and pelvic tenderness also occur with corpus luteum cysts, which can bleed into the peritoneum and mimic pelvic inflammatory disease (PID). PID is defined as a spectrum of upper genital tract inflammatory disorders that may include endometritis, salpingitis, tubo-overian abscess, and pelvic peritonitis. The diagnosis should not be considered conclusive without additional findings, such as a positive cervical culture. The primary pathogens are Neisseria gonorrhea and Chlamydia trachomatis. Cervical cultures for Chlamydia can detect up to 80% of cervical infections; antibody testing, enzyme-linked immunosorbent assay, and DNA probe testing can detect 60% to 90% of infections. Because of this wide range in positive findings, culturing of specimens from the urethra and anus also should be considered. Tubo-ovarian abscess may occur as a complication of PID as well as in postpartum and postoperative patients and in women who use intrauterine devices. The bacteria present in tubo-ovarian access occur in the lower genital tract and may not be the same agents involved in PID.4

Chronic Pain

Chronic pain may begin as an acute episode, change into episodic pain, and then persist for 6 months or longer. From a clinical perspective, chronic pelvic pain can be a symptom of a disease or part of a syndrome. Endometriosis and malignancies are examples of primary illnesses, whereas syndromes include dysmenorrhea, premenstrual syndrome, and chronic pelvic pain disorders.

Endometriosis is the presence of ectopic endometrial glands and stroma outside the uterine cavity. Patients with endometriosis may have dysmenorrhea, dyspareunia, back pain, and rectal discomfort in addition to persistent pelvic pain. The symptoms are related to the site of the endometrial implant. However, the intensity of the pain may not correlate with the size of the implant.5 The incidence is 1% to 2% of the general female population and 15% to 25% in infertile women. Patients may remain asymptomatic until they are being evaluated for infertility. Definitive diagnosis can only be made by laparoscopy, although elevated serum CA-125 levels correlate with severity and reflect the course of the disease. Treatment includes medical and surgical options. The medical treatment for endometriosis includes oral contraceptives, medroxyprogesterone acetate, danazol, and gonadotrophin-releasing analogues. The goals of surgery are to restore normal pelvic anatomy and to resect, coagulate, or vaporize all endometriotic implants.

Adenomyosis is a benign invasion of the wall of the uterus by endometrial tissue. Most patients are 35 to 50 years of age and have had children. Presenting complaints usually dysmenorrhea and menorrhagia.

Uterine leiomyomas (fibroids) are painful when they press on or become entangled in other structures, and cause discomfort when they grow. Dyspareunia, dysmenorrhea, and pelvic pressure are frequent symptoms, along with intermenstrual, postmenstrual, and heavy menstrual bleeding. A degenerating leiomyoma may cause only episodic pain at first and then fever, increased pain, and leukocytosis with a left shift later. Leaking purulent material can cause peritonitis. Leiomyomas undergo malignant transformation in 2 to 3 per 100,000 women, but grow slowly. Surgery used in the treatment of women with heavy bleeding, growths of large size, and additional symptoms.6

Cervical cancer may cause pelvic pain as it metastasizes. Ovarian cancer may be asymptomatic until late stages, when it causes symptoms that are vague and nonspecific. Endometrial cancer in 90% of cases presents with vaginal bleeding or discharge. Pelvic pressure or discomfort occurs from uterine enlargement and then spread of the tumor into extrauterine structures. Any tumor that compresses the bladder or rectum can cause pressure, pain, or dyspareunia.7

Women with ovarian remnant syndrome present with unilateral consent or cyclical pain, as well as postcoital ache, and post-micturition or post-defecation pain. They may have a history of the removal of one or both residual ovaries for pain associated with pelvic adhesions or endometriosis. Although localized abdominal pain is a constant feature of the syndrome, often no mass can be found on pelvic examination. Ultrasound examination is usually diagnostic, revealing a mass that must be distinguished from accessory ovaries, an embrylogic variant of normal development. Treatment is surgical removal of the remnant.8

Women with major gynecologic diseases can have pelvic pain in the form of dysmenorrhea. This term is applied to severe cramping in the lower abdomen, lower back, and upper thighs that occurs during menstruation. Primary dysmenorrhea is the most prevalent source of chronic episodic pain in premenopausal women. It is caused primarily by prostaglandin release from the endometrium at menses, in particular prostaglandins F2 alpha and E2. The cramping pain is often accompanied by nausea, vomiting, headache, diarrhea, and fatigue. Secondary dysmenorrhea and atypical cyclic pain are caused by underlying intrauterine or extrauterine pathology, such as endometriosis, adenomyosis, and other pathology that alters blood flow, increases pressure, or causes irritation of the pelvic organs.

The treatment of primary dysmenorrhea includes nonsteroidal anti-inflammatory drugs (NSAIDs) and oral contraceptive pills. NSAIDs are effective in up to 80% of cases. Other modes of menstrual hormonal suppression are recommended for patients who obtain no relief with NSAIDs and oral contraceptives. Secondary dysmenorrhea requires a thorough evaluation and then treatment of the underlying cause.

Premenstrual syndrome (PMS) includes mood, behavioral, and physical changes that occur during the luteal phase of most menstrual cycles. Studies suggest that about one third of premenopausal women experience some degree of PMS. As in the treatment of dysmenorrhea, underlying illnesses, such as endometriosis and leiomyomas, should be ruled out. Treatment includes NSAIDs for pain, diuretics such as spironolactone for fluid retention, and antidepressants for dysphoria.

Pelvic congestion syndrome is usually seen in premenopausal women, thus suggesting that there is a hormonal factor involved in the venous dilation.9 The capacity of pelvic veins to increase 60-fold by the end of pregnancy makes them, in the nonpregnant state, vulnerable to chronic dilation and stasis. Weakened fascial supports during parturition and the vasodilating effects of cyclically fluctuating hormones aggravate the tendency to dilation.10 The common symptom is a dull, aching pain in the pelvic area that worsens on standing, walking, and lifting and is relieved by lying down. Deep dyspareunia is one of the most consistent symptoms of pelvic congestion syndrome, with an incidence ranging from 71% to 78%. The severity of the pain is determined by the extent of the venous stasis, which leads to hypoxemia and local tissue damage followed by the release of pain-producing substances. The presence of dilated veins in the infundibulopelvic ligament, ovarian hilum, or broad ligament, combined with polycystic changes in the ovary (which may be apparent only on close inspection), is diagnostic of pelvic congestion. Ultrasound and computed tomography (CT) scans are important for revealing polycystic changes in the ovaries and dilated veins in the broad ligament and uterus. Surgical treatment includes hysterectomy and ligation of the ovarian vein. Medical therapy consists of oral contraceptives to suppress ovarian function and intermittent courses of anti-inflammatory agents and antibiotics when inflammation occurs secondary to local infection.11 Radiologic transcatheter embolization of the ovarian veins has been used with varying success.

Sympathetic pelvic syndrome is a chronic pelvic pain disorder that has been recognized because of developments in the study of chronic pain. It is assumed that visceral illness occurs, with pain transmitted to cutaneous areas. The area of innervation includes the cervix and vagina (with innervation from the pudendal nerves, having derivation from S2 through S4), along with the uterus, fallopian tubes, and ovaries (with innervation from the sympathetic pelvic branches of T10 through T12). Repeated local anesthetic nerve blocks are recommended in addition to the medications used in patients with chronic pain.

Another chronic pelvic pain syndrome is focal vulvitis, characterized by burning vulvar pain and superficial dyspareunia. One study found that a majority of patients continued to have symptoms of vulvitis after Woodruff perineoplasty. The authors concluded that surgery was not the best treatment. They noted that these women often had insufficient lubrication or hypertonia of the pelvic floor, or both, during sexual intercourse. Thus, an integrated approach was recommended, including protection of the vulvar skin, relaxation of pelvic muscles, and treatment of psychosexual and relational aspects of the disorder.12

These treatment recommendations are similar to those for patients with chronic pain for whom no pathologic findings have been found. Some studies of chronic pelvic pain in women report that 10% to 50% experience pelvic pain without pathology; other studies cite 15% as the percentage of women who have chronic pelvic pain. The studies citing these statistics then tend to look into symptom clusters for this group of patients. The wide incidence range cited suggests there may be some ambiguity in the definition of chronic pain and in the procedures used to evaluate patients with pelvic symptoms.

The initial patient group can be modified after further study and treatment. Nevertheless, there remains a group for whom no physiologic mechanisms have been elucidated.13,14 These patients have a chronic pelvic pain syndrome that is considered a somatoform disorder similar to irritable bowel syndrome. The prevalence of this syndrome in primary care patients (38%) is comparable to that of asthma and back pain.15 A syndrome of chronic pelvic pain without obvious pathology (CPPWOP) has also been described, but is unclear in these cases whether pathology has been overlooked or limited to findings for specific diseases, such as endometriosis, thus possibly excluding damage to ligaments and smooth and striated muscle. Patients with CPPWOP have a group of symptoms that includes intermittent pain that can vary with the menstrual cycle and is localized to the low abdomen and back. Dyspareunia may be present. Patients tend to be in their 20s and 30s and have a history of childhood sexual abuse, rape, or incest. Present relationships are marked by abuse, divorce, and prostitution.16

Treatment of chronic pelvic pain syndrome or CPPWOP is similar to that of other chronic pelvic pain syndromes and includes NSAIDs and antidepressants. Psychological interventions also have played a role in the treatment of patients with these syndromes. The treatment strategies resemble those for patients with chronic pain with a specific pathology and include methods that help women distract themselves from the pain and encourage them to cope despite the pain.

Women with negative investigations that do not result in an organic diagnosis may then be referred for psychiatric treatment. Despite the apparent presence of anxiety, depression, and possible history of sexual trauma, referral for psychiatric treatment may be resisted. This response is not surprising, given the role psychobiological factors have played in the treatment of women with chronic pelvic pain. Studies of women with chronic pelvic pain syndrome and chronic vulvar pain syndrome have shown a significantly higher incidence of sexual abuse in the two chronic pain groups compared with women who do not have these symptoms. In addition to physical and emotional trauma, there is a significant association between sexual victimization before age 15 years and chronic pelvic pain. Sexual abuse and somatization are highly predictive factors for chronic pain. There also is a higher incidence of depressive symptoms in this group of patients.

The association of sexual abuse, affect and pelvic pain was the basis for psychoanalytic studies of personal development throughout the past century. The first case studies were women with the diagnosis of hysteria, whose symptoms had psychological meaning. The term hysterus is Greek for uterus, and the concept of hysteria (derived from a theory of a “wandering” womb as the basis for inexplicable symptoms in women) historically was the basis for treatments that reflected sociocultural values about the status of women. Hysteria is no longer considered a valid diagnosis; it has been replaced by in current practice by the diagnoses of conversion and somatoform disorders, which may affect both men and women. Nevertheless, the legacy of hysteria as a medical condition persists.

Hysterical conversion has been defined as a special type of somatization in which physical symptoms express a psychological conflict (often sexual) that includes affects that were not sufficiently expressed at the time of the incident, and now represented symbolically. In classical psychotherapy, after elucidating the traumatic precipitant, the next step was to clarify how affects were not expressed directly and were converted into physical symptoms. Patients were said to be using the defenses of repression, denial, and somatization to deal with their feelings. Because of social pressure to limit their direct expression of aggression and their vulnerability to sexual abuse, women were more likely to have chronic pain and to express themselves somatically. Eventually, such women came to be identified with their symptoms; the so-called painful woman who resisted the interpretations put forth for her benefit.17,18

Even today pelvic pain may be considered psychogenic when there is no explicit organic finding because of the persistence of the triad of affect, sexual abuse, and somatization in clinical and psychometric testing studies. Because not all women with chronic pelvic pain have been abused, an alternative explanation has been sought for pelvic pain that occurs without confirming laparoscopic and imaging findings. The biopsychosocial model attempts to integrate physiologic and psychological causes of pain, suggesting the existence of a mind-body dualism in which psychological factors are secondary to physical symptoms. Keeping in mind that physical symptoms in at least one third of cases have no demonstrable organic findings, this model can lead to clinical situations that are difficult to distinguish from early models of hysteria and thus are subject to patient skepticism. This approach is being replaced by theories of central pain mechanisms focusing on neurotransmitters and neural networks that also express affective and cognitive functions. However, a major deconstruction of the studies for chronic pelvic pain needs to be carried out before the diagnosis of hysteria can be considered obsolete.

Whereas women with chronic pain have been referred to multidisciplinary treatment centers to treat complex chronic pain, evaluation and treatment for men has included attempts to establish objective criteria for diagnosis of chronic pelvic pain syndrome. Chronic prostatitis is a poorly understood form of chronic pelvic pain syndrome in men. The diagnosis is based on symptoms, and no measurable parameter can help in defining the presence of the disease, its severity, or cause. A National Institutes of Health (NIH) classification system showed that 38% of men with chronic prostatis had chronic bacterial prostatitis; with 7% of cases resulting from inflammatory chronic pain syndrome, and 55% from noninflammatory chronic pelvic pain syndrome.19

The objectives of current studies include refining and standardizing the evaluation of men with symptoms of chronic prostatitis. Some men have elevated levels of tumor necrosis factor-α and interleukin-1β proinflammatory cytokines. Seminal cytokine levels may provide an objective measure of disease in these patients and suggest specific therapeutic strategies.20 Patients with prostatitis report more perineal, lower abdominal, testicular, penile, and ejaculatory pain than patients with benign prostatic hypertrophy and sexual dysfunction.

Another attempt at determining objective criteria for chronic pelvic pain syndrome is to look for evidence of T-cell reactivity with normal prostatic proteins in autoimmune prostatitis. In one study, the CD4 T-cell proliferative response to seminal plasma was found to be statistically significant when compared with medium alone in men with a history of chronic prostatitis and chronic pelvic pain syndrome, but it was not statistically significant in normal men. The responses of subjects in the chronic prostate/chronic pelvic pain syndrome group and normal subjects to the recall antigens tetanus toxoid and Candida extract were equivalent.21 In studies using color Doppler ultrasonography, chronic prostatitis was associated with abnormal prostate blood flow in men with and without inflammation in comparison with controls.22

In a study of men with pelvic pain, the reported locations of the pain were the prostate or perineal region, or both, in 45.6% of cases, the scrotum or bladder in 38.8% of cases, the penis in 5.8%, the bladder in 5.8%, and the lower abdomen and back in 1.9%.23 Regardless of the location, most subjects had increased urethral sensitivity, suggesting an apparent association of pelvic floor dysfunction with pelvic pain. Treatment was aimed at modulating the pelvic floor with biofeedback, medication, and sacral anterior root stimulation.24

Pelvic floor tension myalgia may contribute to the symptoms in men with chronic pelvic pain syndrome. The presence of detrusor instability, hypersensitivity to filling, or bladder-sphincter pseudodyssynergia on pretreatment urodynamic studies is not predictive of treatment results. Treatment recommendations include a formalized program of neuromuscular reeducation of the pelvic floor muscles plus interval bladder training to improve objective measures of pain, urgency, and frequency in patients with chronic pelvic pain syndrome.25

Pelvic varicocele and seminal vesicle dystrophy are other causes of pelvic pain. In men, diagnosis of varicocele is based on clinical findings (in contrast with women, in whom instrument evaluation is needed to identify causes such as incontinence of ovarian veins or development of adnexal varicosities). Treatment of male varicocele involves percutaneous sclerotization, surgical excision, or therapeutic embolization.26

One study of women with chronic pelvic pain found that more than 75% had irritable bowel syndrome. Of women referred to a gynecologic clinic for dysmenorrhea, dyspareunia, and abdominal pain, half had significantly more symptoms of irritable bowel syndrome than did those referred for symptoms other than pain. Irritable bowel syndrome is a functional bowel disorder of uncertain etiology characterized by a chronic relapsing pattern of abdominal-pelvic pain and bowel dysfunction with constipation or diarrhea, or both. It affects 15% of the population. Symptoms include abdominal pain, bloating, belching, excessive flatus, diarrhea, constipation, passage of mucus, and painful defecation with a sense of incomplete evacuation. Symptoms often are worse during stressful periods and the premenstrual phase of the cycle, and may accompany anxiety and depression.

The pathophysiology of irritable bowel syndrome is multifactorial, involving altered bowel motility, visceral hypersensitivity, and psychosocial factors. Other contributing factors include diet and prior infection. Therapeutic options include increasing dietary fiber to prevent constipation, opioid agents for diarrhea, low-dose antidepressants or infrequent use of antispasmodics for pain, psychotherapy, and hypnotherapy.27 The diagnosis of irritable bowel syndrome is made by taking a careful history and by use of colonoscopy or barium enema to exclude other conditions.

Inflammatory bowel disease may manifest the same symptoms as irritable bowel syndrome. More than 50% of patients with Crohn’s disease and ulcerative colitis present with pain. About 90% of patients with Crohn’s disease have a bloody diarrhea, whereas patients with ulcerative colitis have moderate cramping that resolves with defecation. In one study, chronic pelvic pain was reported in 35% of patients with irritable bowel syndrome and in 13.8% of those with inflammatory bowel disease.28 Women with both irritable bowel syndrome and chronic pelvic pain were more likely to have a lifetime history of dysthymic disorder, current and lifetime panic disorder, somatization disorder, childhood sexual abuse, and hysterectomy than women who had irritable bowel syndrome alone. Logistic regression has shown that the mean number of somatization symptoms was the best predictor of a history of both irritable bowel syndrome and chronic pelvic pain compared with either inflammatory bowel disease or irritable bowel syndrome alone.29

Interstitial cystitis is a chronically progressive, severely debilitating, heterogeneous syndrome that affects the urinary bladder and is characterized by urgency frequency and pain. Its etiology is poorly understood; current hypotheses focus on occult or resistant microorganisms, urothelial hyperpermeability from a defective glycosaminoglycan mucus layer, neurogenic or hormonal dysfunction, mast cell activation, and genetic susceptibility as possible causative factors. The diagnosis is made clinically, by cystoscopy with hydrodistention, and sometimes by biopsy when other pathologies have been excluded.30 This condition is underdiagnosed in women with pelvic pain. Symptoms of urinary frequency and urgency, dysuria, hematuria, and nocturia occur along with the pelvic pain. Patients have often been treated for recurrent urinary tract infections. Urinalysis results may be normal, but microscopic hematuria without white blood cells is sometimes noted. Patients must have at least two of the following symptoms: pain in the suprapubic, perineal, and urethral region; pain on bladder filling that is relieved by emptying; decreased compliance on cystsometrogram; and glomerulations on endoscopy. When these criteria are not met, patients are considered to have urgency-frequency syndrome.

Treatment approaches includes use of systemic agents, instillation therapy, and surgical management. Trials of systemic agents, including antihistamines, azathioprine, corticosteroids, heparin, pentosan polysulfate, and tricyclic compounds have shown inconsistent results. Dimethyl sulfoxide (DMSO) has been used for intravesical therapy, with varying response rates. Surgical treatments include urinary diversion procedures and augmentation cystoplasty. Denervation procedures are reserved for patients with severe, intractable disease. Hypogastric plexus block and neuromodulatory procedures have been used with some success.

Infectious cystitis manifests symptoms of suprapubic pain, dysuria, and frequency and urgency, along with pyuria and a positive urine culture. These symptoms respond to antibiotics. In about 25% of women with irritative urinary symptoms and pyuria, C. trachomatis is found in the urethra. The urethral syndrome occurs when the urinary bacterial count is low, urinalysis is negative, and the Chlamydia study is negative. The etiology of this syndrome is unclear, but it may be caused by chronic inflammation of the periurethral glands, or urethral spasticity with periurethral muscle fatigue. Treatment is similar to that of interstitial cystitis and urgency-frequency syndrome, and consists of a combination of medication, biofeedback, and re-education of voiding habits.31

Evolving lumbar disk disease and intradural neoplasms in the upper lumbar area produce symptoms that may be interpreted as pelvic pain. Symptoms consistent with radiculopathy occur late in the course of these diseases. Musculoskeletal pain can be the result of decreased abdominal and pelvic muscle strength, decreased range of motion of the hip, and unequal leg lengths. Trigger points for this pain may be near surgical incisions.

Surgical procedures can lead to serious pain that develops months to years afterward. An example is the Pfannensteil incision, a horizontal incision across the lower pelvis, which can lead to pulling along the pathway of the ilioinguinal and iliohypogastric nerves. The stretching and trauma arising from labor and delivery also can lead to pelvic pain. The pain is from the lower pelvis, although it may be experienced as visceral in origin.32 Pelvic pain during pregnancy has been associated with symphyseal distention. However, the degree of pain was not proportional to the degree of distention. Studies of pain in pregnancy have attempted to correlate pain with elevated hormones, such as serum concentrations of relaxin and propeptide of type III procollagen measured in early pregnancy.33,34

A similar disproportion occurs in adhesions, which may be responsible for pelvic pain as sequelae of past infection, chronic active inflammatory state, endometriosis, and postoperative adhesions. Celioscopy is the key diagnostic procedure after history taking and physical examination. There is no systematic relation between the clinical picture and anatomic findings. A diagnosis of chronic pelvic pain is recommended in the absence of any macroscopic, histologic, and bacteriologic lesions.35

In laparoscopic studies, about 25% of cases of acute pain and 35% of cases of chronic pain have been attributed to adhesions. The primary sources for the adhesions were in the bowel and omentum. It has been suggested that this pain develops when adhesions fix the pelvic organs in place, hampering their motility. The pain of adhesions can be aggravated by activity. Lysis of adhesions can reduce symptoms of pain, but the duration of relief cannot be predicted. There has been no scientific support for using crystalloids, macromolecular solutions, introperitoneal heparin, corticosteroids, mechanical barriers such as intercede and Gore-Tex, or biodegradable barriers to reduce adhesions.36

A study of laxity in the posterior ligament support of the uterus suggests that the concurrent pelvic pain is attributable to parasympathetic pain at the T12 to L1 level. The pain may result from gravitational pull on nerves that are not being supported by the lax uterosacral ligaments.37

The term vulvar vestibulitis refers to pain that occurs during sexual intercourse. The diagnosis is based on the presence of dyspareunia that lasts for at least 6 months and red areas in the vestibulum that are extremely sensitive to touch. The etiology is multifactorial and includes repeated use of antibiotics, local treatment of Candida and human papillomavirus infections, use of hormonal contraceptives, frequent use of local substances that may be irritative, lack of arousal, vaginismus, and tense pelvic floor muscles. There is increased intraepithelial innervation and no inflammation. Treatment includes biofeedback, tricyclic antidepressants, psychotherapy, and surgery.38

Pudendal nerve entrapment should be considered as a differential diagnosis in patients with anoperineal pain. The idea that pudendal nerve entrapment is the cause of some pelvic pain syndromes has gained momentum in the past 15 years.39,40 The pudendal nerve navigates along a tortuous path, supplying sensation to virtually the entire pelvic area including the penis, scrotum, perineum, and rectum, as well as motor function to the pelvic floor musculature and urethral sphincter. The two major areas of entrapment include the junction of the sacrotuberous and sacrospinous ligaments, and the pudendal canal of Alcock. Evaluation of this pathology includes reproduction of pain on application of intrarectal digital pressure at the ischial spine. In addition, intrarectal stimulation of the pudendal nerve trunk and a recording response in the bulbospongiosus muscle with distal motor latency longer than 5.0 msec is suggestive of pudendal neuropathy. The pain can be abolished by fluoroscopy or CT-guided local anesthetic and corticosteroid injection at the ischial spine or the canal of Alcock.41

Coccygodynia is a common problem, characterized by pain and tenderness at the tip of the spine or in the coccyx. The pain frequently radiates to the perineal, gluteal, and posterior sacral areas; worsens on sitting; and is eased on standing. Treatment consists of massage, local heat, injection of the sacococcygeal joint with local anesthetic and corticosteroid, and, if indicated, psychological therapies. Tension myalgia refers to spasm of the involved muscles, which can be the levator ani, the piriformis, or the coccygeus muscle groups. Treatment includes heat and massage, local anesthetic injection of the muscles, and follow-up exercises.42

Pelvic joint instability and persistent pelvic pain can occur in instances of precocious puberty and use of oral contraceptives prior to the age of reproduction. Diagnosis is based on a history of early onset of menarche. Osteoporotic sacral fractures are associated with pelvic pain.

Sports-related injuries and pain include pyramidal muscle hematoma, osteitis pubis, and adductor tendonitis. Pyramidal hematomas can cause impingement of the sciatic, inferior gluteal, and pudendal nerves when the nerves are compressed between the muscle and the iliac spine. Osteitis pubis, considered to be the most common inflammatory disease of the pubic symphysis, is a self-limiting inflammation secondary to trauma, pelvic surgery, childbirth, or overuse. It occurs more often in men during the third and fourth decades of life, causing pain in the pubic area, one or both groins, and in the lower rectus abdominis muscle. The pain may be exacerbated by exercise or by specific movements, such as running, kicking, or pivoting on one leg, and is relieved with rest. During the physical examination, pain can be elicited by resisted long and flexed adductor contraction. A waddling antalgic gait and symphysis tenderness also can occur. Initial therapy should focus on decreasing inflammation with active rest, ice, NSAIDs, and physical therapy. If necessary, judicious use of local corticosteroids may be attempted.43

Medical Therapy

NSAIDs have been studied extensively in the treatment of primary dysmennorrhea and have proven efficacy in various causes of pelvic pain. Combination estrogen-progestin oral contraceptives, danazol, and gonadotropin-releasing hormone agonist are used in a stepwise sequence in the management of pelvic pain secondary to endometriosis. Other adjuvant medications, such as tricyclic antidepressants, have a role in some chronic pelvic pain conditions.

Neural Blockade

Hypogastric Plexus Block

This type of block is used to modulate pain that results from a sympathetic mechanism originating in the pelvic viscera. Several techniques have been described for performing hypogastric plexus block. Needle placement with fluoroscopy from the posterior approach, using landmarks and coaxial imaging technique, is commonly used. A transdiskal approach through the L5-S1 disk using fluoroscopy or CT guidance has been reported. An anterior approach under CT guidance may be used in selected cases. Neurolytic hypogastric plexus is quite effective in relieving pelvic pain in patients with gynecologic, colorectal, or genitourinary cancer.43

Ganglion Impar Block

This block is used to evaluate and manage pain of sympathetic origin that has its root in the perineum, rectum, or genitalia. There are various techniques for performing this block. One technique uses fluoroscopic guidance and an approach via the trans-sacrococcygeal with a straight needle44 (Fig. 35-2). Another technique involves entering at the level of the anococcygeal ligament with a curved needle45 (Fig. 35-3). Neurolysis of ganglion impar is used for refractory cases of perineal pain. Neurolysis can be achieved by using chemicals such as phenol or by cryoablation or radiofrequency lesioning.

Pudendal Nerve Blockade

Pudendal neuralgia should be considered in the differential diagnosis of long-term anoperineal pain. In women, the block is performed transvaginally with the patient in the lithotomy position. The needle tip must be advanced through the sacrospinous ligament just past the ischial spine. The transperineal approach is used in men, and in women in whom anatomical constraints preclude a transvaginal approach. CT-guided pudendal nerve block has also been reported as a very effective technique in the treatment of pudendal neuralgia.46

Neuromodulation

Sacral neuromodulation, which involves insertion of sacral nerve stimulators, has been performed for patients with voiding disorders, including urinary urge continence, urgency-frequency, and nonobstructive urinary retention; for patients with intractable interstitial cystitis; and for those with chronic intractable pelvic pain.47 This technique is especially beneficial in patients with bladder sphincter dysfunction because it restores balance between the sacral reflexes. Electrical stimulation of the S3 nerve activates the pelvic floor and modulates innervations of the bladder, sphincter, and pelvic floor.

Neuraxial Drug Delivery

Delivery of an analgesic into the epidural or subarachnoid space is used most often in the management of patients with pain secondary to malignancy. Opioids remain the most commonly used drugs for this therapy; however, several other agents, such as local anesthetics and clonidine, can be used in conjunction.

Neuroablation

In patients with unilateral pelvic pain secondary to malignancy cordotomy or rhizotomy can be used in selected patients. The side effects include paresis, ataxia, and bladder dysfunction.

Surgical Therapy

Laparoscopy

In a review of 1,524 gynecologic laparoscopies performed for chronic pelvic pain, endometriosis was the most commonly diagnosed disorder (33%), followed by adhesive disease (24%), chronic PID (5%), ovarian cysts (3%), pelvic varicosities (< 1%), leiomyomata (< 1%), and a variety of other diagnoses (4%). No visible pathology was detected in 35% of patients.12 Resection and ablation of the endometriotic lesions, and lysis of adhesions are the two therapeutic approaches commonly employed laparoscopically.

Nerve Transection Procedures

Laparoscopic uterosacral nerve ablation involves the destruction of the uterine nerve fibers that exit the uterus through the uterosacral ligaments. There seems to be little evidence to support the performance of this procedure.48

Presacral neurectomy is a procedure designed to interrupt the sympathetic innervation of the uterus at the level of superior hypogastric plexus. It is performed by incising the pelvic peritoneum over the sacrum and then identifying and transecting the sacral nerve plexus. This procedure is more helpful in the management of patients with persistent midline pelvic pain.

Role of Gonadectomy and Hysterectomy

Bilateral oophorectomy with or without hysterectomy is the most effective procedure for women who have recurrent symptomatic endometriosis and who have no desire to retain reproductive function.

Multidisciplinary Treatment

Pelvic pain is the end result of disease-initiated stimuli and the interpretation of these stimuli by the central nervous system. It is a complex interaction that involves sensory, psychological, and environmental factors. Hence, applying a multidisciplinary approach, which employs an integrative approach to the psychosocial-mind-body paradigm, is sometimes the most effective strategy in the management of patients with chronic pain states. This approach integrates medical intervention with identification and management of socioenvironmental problems, cognitive behavioral pain strategies, and treatment of concurrent psychological morbidity. Available evidence suggests that outcomes, including pain severity, general health, and functional status and disability, improve more significantly after this approach than after isolated medical or surgical interventions.

Physical Therapy

Pelvic floor manual therapy, which involves decreasing the pelvic floor hypertonicity, may ameliorate the symptoms of urgency-frequency syndrome and interstitial cystitis.49 Other physical therapy modalities, including heat, electrical stimulation, deep ultrasound, and massage, may be used depending on the individual need of the patient.

Psychological Treatment

The various psychological modalities of treatment should be selected based on individual need, which can vary dramatically among patients. Behavioral therapy, progressive relaxation training, guided imagery, self-hypnosis, breathing exercises, and biofeedback are some of the techinques employed. Other options that may be more useful in the setting of chronic pelvic pain include group therapy, couples therapy, and sex therapy.

Alternative Medicine

Alternative or complementary medicine is receiving greater interest from both patients and health care providers. Yoga, meditation, chiropractic treatment, acupuncture, and magnet therapies are some of the common forms of these modalities used in the treatment of pelvic pain.

Pelvic pain remains a diagnostic and therapeutic challenge for the health care provider. It is a source of frustration to both the physician and patient. Physicians have been ill equipped through their training to confront the multifaceted nature of the complaints of patients with chronic pelvic pain. Patients presenting with these pain syndromes are best assessed and treated using a multidisciplinary approach. Close collaboration among gynecologists, urologists, proctologists, neurologists, pain specialist, gastroenterologists, psychiatrists, psychologists, physiatrists, and neurologists is needed. Special emphasis should be placed on preventive strategies, such as screening and treatment of avoidable conditions (e.g., lower genital infection) that can result in PID. Preventive measures also are needed to tackle the growing incidence of childhood and sexual abuse, which play a role in chronic pain syndromes.