37.1 Coccygodynia

Coccygodynia (coccydynia, coccyalgia) denotes pain in the coccyx, which may be functional or organic in origin. Patients complain of aching, cramping, or sharp pain that is localized in the region of the coccyx or sometimes radiates to the buttocks or down the backs of the thighs. At times, the attacks of pain can become sharp, shooting, or breathtaking. Patients with symptoms of coccygodynia usually seek the opinions of numerous orthopaedic surgeons, gynecologists, neurologists, and colon and rectal surgeons to try to seek help.

A recent review by Lirette provides an excellent summary of the overview and management of coccydynia. ¹ While the term was first coined by Simpson in 1859, the accounts of coccygeal pain date back as early as the 16th century. Treatment is often difficult because of the multifactorial nature of its etiology. Both physical and psychological factors can contribute. The condition is five times more common in women than in men, and teens and adults are more likely to present with coccygeal pain as compared to children. Significant weight loss, leading to lack of cushioning, may also be an etiologic factor. Some authors attribute female predominance to the more posterior location of the sacrum and coccyx and the characteristics of the ischial tuberosities that leave a woman’s coccyx more exposed and susceptible to trauma both in common situations (sitting position) and during childbirth. The coccyx is larger in women than in men and is therefore more susceptible to injuries. A high incidence of the disorder has also been reported in debilitated elderly patients. ²

37.1.5 Organic Coccygodynia

Organic coccygodynia may arise either from rigidity of the sacrococcygeal joint or from traumatic arthritis. Fracture and dislocation of the coccyx with displacement are usually a result of direct violence but may occur during difficult childbirth. Coccygodynia has also been attributed to so-called pericoccygeal glomus tumors. ⁵ However, an autopsy study of 20 coccyges from fetuses, infants, and adults revealed intracoccygeal glomera in 6 of 9 pediatric specimens and all 11 adult specimens. All were microscopic structures, and none appeared to cause bony destruction or erosion. Their role in the pathogenesis of coccygodynia is therefore questionable.

The symptoms of local pain during sitting and during defecation are attributed to spasm of the surrounding muscles. Pain is exquisite, and tenderness is sharply localized over the coccyx. In a patient with a recent injury, swelling and ecchymosis may be found over the lower sacral region. The diagnosis is made if abnormal mobility at the coccygeal articulation and accompanying sensitivity and tenderness are present. ⁶ Other symptoms include pelvic floor muscle spasms, referred pain from lumbar pathology, arachnoiditis of the lower sacral nerve roots, local posttraumatic lesions, and somatization. ² Marx ⁷ suggested that if the injection of a mixture of local anesthetic (4 mL 1% lidocaine and 4 mL 0.5% bupivacaine) with a depository steroid (100-mg prednisone) into the pericoccygeal soft tissue resulted in relief of pain within a few minutes, the diagnosis of coccygodynia is confirmed. Coccygeal pain resulting from acute trauma responds well to conservative management with nonsteroidal anti-inflammatory drugs (NSAIDs) and sitting aids (donut pillow).

Treatment generally consists of reduction by digital manipulation through the rectum, but that may fail because of the muscle forces continually in play. ⁶ Bed rest for approximately 1 week is usually sufficient to alleviate majority of the symptoms. Tight cross-strapping of the buttocks lessens pain in some patients, but exacerbates it in others. The patient should sit on an inflated rubber ring. Sitting on one buttock at an angle may be sufficient to eliminate the discomfort of sitting squarely on both ischial tuberosities. Some patients prefer a hard surface that allows the ischia to bear most of the body weight. ⁶ Sitz baths help relieve muscle spasm, and stool softeners should be provided so that constipation does not aggravate symptoms.

Other therapeutic possibilities include blockade of the ganglion of Walther (or ganglion impar), electrical spinal cord stimulation, and selective nerve root stimulation. ² Coccygectomy should be considered for those patients who have severe disability following a coccygeal fracture. To determine whether surgery probably will be beneficial, Steindler advised infiltrating the region of the coccyx with a local anesthetic; if temporary relief is obtained, then, according to them, coccygectomy probably will relieve the pain. ⁶ Wray et al ⁸ conducted a 5-year prospective trial involving 120 patients to investigate the etiology and treatment of coccydynia. The cause lies in some localized musculoskeletal abnormality in the coccygeal region. The condition is genuine and distressing and they found no evidence of neurosis in their patients. Physiotherapy was of little help in treatment, but 60% of the patients responded to local injections of corticosteroid and local anesthesia. Manipulation and injection was even more successful and cured about 85%. Coccygectomy was required in almost 20% and had a success rate of over 90%.

Operation is generally contraindicated for acute sacrococcygeal injuries even when the coccyx is severely anteriorly angulated. Operation is also contraindicated when the low back is painful because occasionally coccygodynia or rectal pain is an early symptom of pathologic change in the lumbosacral disc. ⁹

Operative removal of the coccyx is accomplished through a paramedian incision that extends from the sacrococcygeal junction distally. ⁶ The sacrococcygeal joint is disarticulated and dissection is continued distally along each side of the bone. The sharp distal margin of the sacrum should be beveled so that no prominence remains. The pelvic diaphragm is repaired by reanchoring the structures stripped from the coccyx, and the gluteus maximus muscle is reattached to the posterior sacral aponeurosis.

Grosso and van Dam ¹⁰ reported on nine patients who underwent total coccygectomy. There was one postoperative wound infection. With an average follow-up of 56 months, three patients reported complete relief of pain, five reported marked improvement, and one reported slight improvement.

Doursounian et al ¹¹ operated on 61 patients with instability-related coccygodynia. There were 49 women and 12 men, with a mean age of 45.3 years. Twenty-seven patients had hypermobility of the coccyx and 33 had subluxation. In all cases, the unstable portion was removed through a limited incision directly over the coccyx. Follow-up was between 12 months and more than 30 months. The outcome was rated excellent or good in 53 patients, fair in 1, and poor in 7. There were nine patients with infection requiring reoperation. Hodges et al ¹² assessed the outcomes after conservative and surgical therapy in 32 patients presenting with symptoms of coccydynia. Patients completed visual analog pain scales and the Oswestry functional capacity index. Of the 32 patients, 13% were treated with NSAIDs alone, 53% were treated with NSAIDs, followed by local injections, and 34% underwent coccygectomy after failure of NSAIDs or local injection. Patients undergoing operation had significantly greater pretreatment VAS scores (8.3 vs. 5.4). Surgical patients also had greater Oswestry Low Back Disability (OSW) scores, but not significantly (36.6 vs. 24.2). Marked improvement was reported by 82% of the surgical patients. Wound infections developed in 27% of the surgical patients and 9% developed wound dehiscence. All infections resolved following irrigation and debridement and a short course of oral antibiotics. Ramsey et al ¹³ reviewed the clinical results of the treatment of coccygodynia. Twenty-four patients were treated with local injections and 15 patients treated with coccygectomy. Local injections were successful in 78% and coccygectomy was successful in 87% of the patients. Perkins et al ¹⁴ reviewed 13 patients of a mean age of 45 years who underwent coccygectomy. Pain was assessed by the numerical rating scale and function by OSW at a mean of 43 months. There were two complications and the numerical rating scale improved from 7.3 to 3.6 and the OSW improved from 55 to 36.

A newer approach to the treatment of coccydynia involves radiofrequency ablation. A cohort of 12 patients, inclusive of 10 males and 2 females, at Johns Hopkins in Walter Reed National Military Medical Center were treated with pulsed or conventional radiofrequency treatment. This therapy was aimed at ablation of the sacrococcygeal nerves in patients who have failed more conservative measures. In this study, the average benefit was a 55% pain relief based on VAS scores. Patients who underwent prognostic neural blockade were more likely to experience a positive outcome. ¹⁵

De Andrés and Chaves ² offered the algorithm presented in ▶ Fig. 37.1 for the diagnosis and therapeutic approach to coccygodynia.

37.2 Endometriosis

Endometriosis is characterized by the presence of ectopic endometrial glands and stroma outside of the uterine cavity. This relatively common disorder may affect up to 15% of all women of reproductive age, and may be responsible for one-third of women experiencing infertility. Its manifestations can range from asymptomatic to intractable and disabling pain. The degree of symptoms does not always correspond to the extent of disease seen at surgery. Diagnosis is clinically suspected and usually confirmed at the time of laparoscopy or laparotomy.

The exact etiology of endometriosis is unknown, though it is postulated to arise from either coelomic metaplasia, in which peritoneal epithelium undergoes metaplastic change into endometrial tissue ¹⁷ or implantation of viable endometrial cells through retrograde menstruation from the fallopian tubes. Endometriosis is most commonly found in the pelvis, affecting the ovaries in 60 to 75% of cases. The next most common sites in decreasing order of frequency are the uterosacral ligaments, cul-de-sac, uterus, and rectosigmoid colon in 3 to 10% of cases. Less commonly, endometriosis may affect the appendix, ureter, bladder, surgical scars, and, rarely, via hematogenous dissemination, the lungs, resulting in catamenial pneumothorax. ▶ Table 37.1 shows the sites and incidence of endometriosis. An estimate of the incidence of endometriosis is approximately 4 to 17% of women in the reproductive age group. Although the incidence of colorectal involvement in women with endometriosis has been reported as high as 50%, involvement severe enough to necessitate bowel resection is less than 10%. ¹⁸

37.3 Proctalgia Fugax and Levator Syndrome

Proctalgia fugax may be defined as pain seemingly arising in the rectum that recurs at irregular intervals and is unrelated to organic disease. ³⁹ The term “proctalgia fugax” was first introduced by Thaysen ⁴⁰ in 1935, and Schuster ⁴¹ has provided an excellent description of the clinical presentation. The onset of pain during the day or night is abrupt, and patients may be awakened with pain several hours after falling asleep. The pain appears suddenly mostly at night without any particular warning and disappears completely without any objective traces. The pain varies in severity but often is excruciating. Symptoms last from only a few minutes to less than half an hour, and their duration, although variable from patient to patient, is constant in a given patient. The pain is described variously as gnawing, grinding, cramp-like, sharp, or tight. It is localized in the rectal region above the anus, varying in location from person to person but remaining constant in a given person. Symptoms spontaneously disappear without residue except for a weak, washed-out feeling after particularly severe attacks. There are no associated intestinal disturbances such as alteration in bowel habits, tenesmus, or paresthesias.

The etiology of proctalgia fugax is unknown, although it has been suggested that it is due to spasms of the levator ani muscles. ³⁹ A unique study was reported by Harvey, ⁴² who obtained intraluminal pressure recordings from the rectum and sigmoid colon in two patients experiencing attacks of proctalgia fugax. In each case, the pain appeared to result from contractions of the sigmoid colon and not from spasm of the levator ani muscles.

Takano ⁴³ reported his experience with 68 patients with proctalgia fugax, among whom 55 patients had tenderness along the pudendal nerve. The location, character, and degree of pain caused by digital examination were confirmed by all of them to be similar to that which they experienced at times of paroxysm. After administration of a nerve block, symptoms disappeared completely in 65% of the patients and decreased in 25%. These data suggest that the pathogenesis of proctalgia fugax is neuralgia of the pudendal nerves.

The condition occurs in approximately 14% of healthy people and is more common in women (17.3%) than in men (8.8%). ⁴⁴ Between attacks, no consistent physical abnormality is evident. The absence of any objective abnormality suggests that at least a portion, if not all, of these cases are of psychogenic origin. A study of 48 patients with proctalgia fugax by Pilling et al ⁴⁵ revealed that the majority of the patients had professional or managerial occupations. They were found to be perfectionistic, anxious, and tense; had a relatively high incidence of neurotic symptoms in childhood; and were of above-average intelligence. The authors believed that the tendency of this anxious, perfectionistic group to somatize emotional conflicts by pain in the gastrointestinal tract is strong evidence that proctalgia fugax is of psychogenic origin.

Treatment of this condition is unsatisfactory. Firm upward pressure on the anus can provide relief. Other measures that have been used include taking hot sitz baths, having a bowel movement, inserting a finger into the anus, massaging the muscles, or administering an enema. Such maneuvers probably only pass the time for patients who have a condition in which the duration of pain is self-limited. Inhalation of amyl nitrite or sublingual nitroglycerin has also been used. Eckardt et al ⁴⁶ conducted a randomized, double-blind, placebo-controlled, crossover trial of inhaled salbutamol in 18 patients with proctalgia fugax and found that salbutamol inhalation shortened the duration of severe pain. Interestingly, in the asymptomatic state, there were no changes in anal resting pressure, anal relaxation during distention, or rectal compliance. Nightly doses of quinine have been recommended for patients who have frequent repeated nocturnal attacks. ⁴⁰ Anesthetics, sedatives, and spasmolytic agents have been employed. ⁴⁶ Peleg and Shvartzman ⁴⁷ described a case where a single dose of an intravenous lidocaine infusion completely stopped pain attacks. Katsinelos et al ⁴⁸ described a case of proctalgia fugax responding to anal sphincter injection of clostridium botulinum type A toxin. Lowenstein and Cataldo ⁴⁹ reported a case of proctalgia fugax that responded to 0.3% nitroglycerin ointment. Sinaki et al ⁵⁰ reported that diazepam was helpful in 40% of their patients.

A closely allied condition, if not a variation of the same theme, is the so-called levator syndrome. Individuals with this syndrome experience a dull ache or pressure in the rectum, sometimes describing the sensation as “sitting on a ball” or “having a ball in my rectum.” The pain is worse during sitting and disappears when the patient stands or lies down. Precipitating factors have included the trauma of a long-distance ride in a car, childbirth, lumbar disk surgery, low anterior resection or abdominoperineal resection of the rectum, gynecologic operations, and occasionally sexual intercourse. ⁵¹ Often no etiologic factor can be elicited, and a large component of the condition has been attributed to a psychological overlay. The prevalence of this condition has been reported as 6.6% of the general population in the United States ⁵²

The syndrome occurs more commonly in women, usually in the fourth to sixth decades of life. The diagnosis is made by the demonstration of tenderness and spasm of the affected muscle, which are usually unilateral and on the left side.

Treatment consists of puborectalis muscle massage up to 50 times, performed in a firm manner based on the patient’s tolerance and carried out at 3- to 4-week intervals. Warm baths and short-term judicious use of diazepam also can be of value. For patients who do not respond to these measures, Sohn et al ⁵³ first described the use of electrogalvanic stimulation as a treatment. The rationale for this therapy is based on the fact that a low-frequency oscillating current applied to a muscle induces fasciculation and fatigue, which breaks the spastic cycle. The treatment is painless, and no adverse side effects are known. Success rates of 60 to 94% have been reported. ^{51 , 53 , 54 , 55} Recurrence rates are significant. In the series by Billingham et al, ⁵⁵ only 25% of the patients remained symptom free. Further improvement can be obtained through retreatment. ⁵⁴ Less favorable results were reported by Hull et al ⁵⁶ in a series of 52 patients; 50% received fewer than four 1-hour treatments, 33% received four to six treatments, and 17% received more than six treatments. The treatment was painless in 77%. With an 88% follow-up with a mean of 28 months, there was symptom relief in 19% of the patients, partial relief in 24%, and no relief in 57%. Total treatment failures may be due to a large psychological component and should be treated accordingly. ⁵¹ Hull et al ⁵⁶ found that misdiagnoses included recurrent pelvic carcinoma and fissure-in-ano. Recognition of this disorder is important to avoid unnecessary and expensive diagnostic investigations, or worse, totally needless operations.

Heah et al ⁵⁷ assessed the effects of biofeedback on pain relief in 16 consecutive patients (9 men, 7 women, mean age 50 years) with levator ani syndrome. Mean duration of pain was 32.5 months. All underwent a full course of biofeedback using a manometric balloon technique. Mean follow-up was 12.8 months. An independent observer prospectively administered pain scores. After biofeedback, the pain score was significantly improved (median 8 vs. 2). Analgesic requirements were also significantly reduced (all 16 patients needed NSAIDs before biofeedback; only 2 patients needed NSAIDs after biofeedback).

37.4 Melanosis Coli

Melanosis coli is characterized by a deep pigmentation of the mucosa of the colon and rectum caused by the presence of a melanin-like pigment (▶ Fig. 37.2). It may involve the large bowel from the rectum to the ileocecal valve, with a sharp demarcation at this point. This dramatic demarcation is seen at an ileocolic anastomosis (▶ Fig. 37.3). The color of the mucosa varies from shades of yellowish brown to black. It is seen in the appendix but not the terminal ileum. Examination reveals adenomatous polyps and adenocarcinomas rendered strikingly apparent by their lack of pigmentation against the blackish background of the surrounding mucosa (▶ Fig. 37.4). ⁵⁸ Moreover, nonpigmented areas of mucosa that are not grossly abnormal ultimately prove to be adenomatous hyperplasia. Current data suggest that adenoma detection rate may be increased in the setting of melanosis coli, likely due to enhanced identification made possible by pigmentation differences. ⁵⁹

Melanosis may be obvious to the naked eye, but the vast majority of cases are apparent only on microscopic examination. Histologically, the melanin-like pigment is found in histiocytes within the lamina propria and may be seen in the submucosa and even in the regional lymph nodes. ⁶⁰ There is a lack of inflammatory change in the colon. Walker et al ⁶¹ reported an electron microscopic study that showed apoptosis of colonic surface epithelial cells and phagocytosis of resulting apoptotic bodies by intraepithelial macrophages. The latter migrated to the lamina propria where intracellular degradation of the apoptotic bodies resulted in formation of lipofuscin, characteristic of this condition.

Ewing et al ⁶² reported the case of a patient who underwent a left hemicolectomy for colonic adenocarcinoma and was found incidentally to have melanosis coli associated with long-term use of the herbal laxative Swiss Kriss® (Modern Products, Inc., Mequon, WI) not only in his colonic mucosa, but also in the colonic submucosa and in his pericolic lymph nodes. To their knowledge, the presence of identical pigment in macrophages of pericolonic lymph nodes has been reported in only four other patients in the English literature. Use of a member of the laxative family, which consists of derivatives of anthraquinone (cascara, aloes, rhubarb, senna, and frangula), contributes to this pigmentation. ⁵⁸

In most instances, the laxative had been taken almost daily for 1 year or more. This distinct group of cathartics owes its activity to the presence of an irritating anthracene or emodin. The exact mechanism of pigment formation is uncertain. Perhaps the active ingredient of these laxatives contains a pigment or elaborates a pigment within the colon that is phagocytized by the deep mucosal cells.

Pardi et al ⁶³ reported 25 patients with inflammatory bowel disease and melanosis coli, 20% of whom had documented laxative use. Most patients had ulcerative colitis (72%) or Crohn’s colitis (24%), and the mean duration of inflammatory bowel disease was more than 7 years. These data raise the possibility that chronic colitis could cause melanosis coli even in the absence of laxative use.

Reports of the incidence of melanosis coli vary from 1 to 5%, ⁵⁸ and in unselected constipated patients it has been observed in 12 to 31%. ⁶⁴ Melanosis coli occurs in all races. In a histologic study of 200 autopsy cases, Koskela et al ⁶⁵ found a prevalence of 60% for melanosis coli, a prevalence that increased with age: 20 to 54 years, 30% and older than 75 years, 71%. Melanosis was more common in the proximal part of the colon: ascending colon, 49%; sigmoid, 18%; and rectum, 6%. Earlier writers suggested that melanosis coli is found in the older age group; however, this, probably, is related to the duration of the ingestion of these laxatives. There is a female preponderance of from 3:1 to 8:1, which probably reflects the greater incidence of constipation and habitual use of laxative agents among women.

Morgenstern et al ⁵⁸ found that pigment-bearing macrophages are absent from benign and malignant neoplasms and from surrounding normal mucosa. They postulated that the neoplastic epithelium elaborates some substance that inhibits the aggregation or function of macrophages. How this might be related to neoplasia, if at all, is unknown.

Melanosis coli cannot be held responsible for any known symptom complex. A history of constipation is almost universally present, for it is in constipated patients who ingest these laxatives. As a rule, the pigmentation disappears within a period of 4 to 12 months after discontinuation of all anthracene laxatives.

In a colonoscopic study of 2,277 patients, Nusko et al ⁶⁶ found no significant increase in colorectal carcinoma rate either in laxative users or in patients with melanosis coli.

Subsequently, Nusko et al ⁶⁷ performed a prospective case-control study to investigate the risk of anthranoid laxative use for the development of colorectal adenomas or carcinomas. A total of 202 patients with newly diagnosed colorectal carcinomas, 114 patients with adenomatous polyps, and 238 patients (controls) who had been referred for total colonoscopy were studied. The use of anthranoid preparations was assessed by standardized interviews, and endoscopically visible or microscopic melanosis coli was studied by histopathological examination. Use of neither anthranoid laxative, even in the long term, nor macroscopic or microscopic melanosis coli was associated with any significant risk for the development of colorectal adenoma or carcinoma.

The associations among colorectal carcinoma and constipation, anthranoid laxative use, and melanosis coli are controversial. Nascimbeni et al ⁶⁸ investigated the relationship between sigmoid carcinoma and constipation, anthranoid laxative use, and melanosis coli using aberrant crypt foci analysis as an additional tool of investigation. Fifty-five surgical patients with sigmoid carcinoma, 41 surgical patients with diverticular disease, and 96 age- and sex-matched patients without intestinal disease (controls) were interviewed on their history of constipation and anthranoid laxative use. Constipation and anthranoid laxative use were similar between patients with sigmoid carcinoma (30.9 and 32.7%, respectively) and those with diverticular disease (39 and 28.6%) but higher than among controls (18.8 and 8.3%). Melanosis coli was found in 38.2% of the patients with sigmoid carcinoma and 39% of those with diverticular disease. This study confirms the association of aberrant crypt foci frequency with colon carcinoma and does not support the hypothesis of a causal effect relationship of colorectal carcinoma with constipation, anthranoid laxative use, or melanosis coli. Interestingly, melanosis is often difficult to distinguish from certain presentations of mucosal ischemia, and thus clinicians must have a high index of suspicion and keep the diagnosis of melanosis as part of the differential. ⁶⁹