Physical examination must be thorough and complement the history in order to exclude systemic etiology. Evidence of systemic illness, including neurologic or muscular deterioration, and endocrine or metabolic disorders, should be sought. In addition, special attention should be directed to the abdominal and anorectal regions.
The abdominal examination may detect excessive stool or gaseous distention and the presence of surgical scars that are evidence of neoplasic or inflammatory bowel diseases. Palpation may reveal a soft mass in patients with a dilated rec-tosigmoid filled with stool, a tender mass in the left lower quadrant, suggestive of a diverticular disease, or a hard mass that is more characteristic of a neoplasm. Percussion can differentiate gaseous distention from ascites. Finally, auscultation may reveal hyperactive waves in patients with abdominal distention, which can be visualized in the relaxed patient and characteristic of partial bowel obstruction or hypoactive or absent ileal sounds.
Both the lateral decubitus and prone jackknife positions are adquate for routine anorectal examination. Although the prone position allegedly provides wider exposure, the left lateral decubitus is a good alternative and better accepted by patients, particularly the elderly or those otherwise incapacitated. Occasionally, however, in order to reveal a rectal prolapse, it may be necessary to place the patient in a squatting position.
The anorectal examination should begin by inspection of the patient's undergarment and perineal skin for evidence of fecal soiling. Soiling may result from overflow incontinence associated with fecal impaction ("overflow or paradoxical fecal incontinence"), especially in elderly patients. This situation must be differentiated from true incontinence due to sphincter dysfunction and "humid anus" or pseudoincontinence, which is caused by hemorrhoidal prolapse, pruritus ani, perianal fistula, rectal mucosal prolapse, and anorectal venereal diseases, and should be excluded. Perineal examination will exclude anatomic causes of constipation such as tumors, stenosis, fissures, or an ectopic anus.
Increased perineal descent can also be estimated during physical examination by observing the perineum during the Valsalva maneuver with the patient in the left lateral position with the buttocks separated. A perineometer, an instrument consisting of a freely moving graduated cylinder within a steel frame positioned on the patient's ischial tuberosities, has also been used. Neither method is physiologically appropriate, as evaluation is undertaken with the patient in the lateral decubitus position and during feigned, rather than actual, expulsion of intrarectal contents.40 Defecography criteria include perineal descent exceeding 3.0 cm during maximal push effort as compared to that measured at rest (increased dynamic perineal descent) and perineal descent exceeding 4.0 cm at rest (increased fixed perineal descent).41
The perineal descent syndrome is considered a component of a vicious cycle involving excessive and repeated straining, protrusion of the anterior rectal wall into the anal canal, a sensation of incomplete evacuation, weakness of the pelvic floor musculature, more straining, and further pelvic floor weakness.42 Excessive perineal descent is a physical sign indicative of pelvic floor weakness. However, it may merely represent one facet in a constellation of varied symptoms and findings. Patients with abnormally increased perineal descent may present with rectal prolapse, partial or major incontinence, obstructed evacuation, solitary rectal ulcer syndrome, or vague symptoms of incomplete evacuation or rectal pain. Potential surgical disorders such as large nonemptying rectocele, enterocele, or sigmoidocele may coexist.
During simulated defecation, the anal verge should be observed for any patulous opening or rectal prolapse. Patients with constipation may have signs of anal incontinence during physical examination due to progressive neural injury related to chronic straining or an associated neuromuscular lesion due to childbirth. Occasionally, fecal incontinence is suspected only during physical examination or even during physiologic testing. This may occur due to the patient's embarrassment and unwillingness to seek medical therapy or as a subclinical finding.
Cutaneous sensation around the anus may be absent in patients with neurogenic disorders and may also indicate the level and location of the lesion. An intact bilateral anal reflex, as tested by a light pinprick or scratch, demonstrates that innervation of the external sphincter mechanism is present. Fecal impaction is often noted in children and elderly individuals with symptoms of severe constipation and soiling (paradoxical fecal incontinence). Constipated patients often have hard stool in the rectal vault. Patients with Hirschsprung's disease usually have an empty contracted distal rectum.
The next step is gentle palpation with a well-lubricated gloved index finger to evaluate resting tone. The lower rounded edge of the internal anal sphincter can be palpated on physical examination at approximately 1.2 cm distal to the dentate line. The entire circumference of the anorectum should be palpated by gentle circum-anal rotation of the examining finger to assess the integrity of the anorectal ring. This is a strong muscular ring that represents the upper end of the anal sphincter, more precisely the puborectalis, and the upper border of the internal anal sphincter around the anorectal junc tion. In patients with spine lesions, return of anal resting tone after digital examination is characteristically very slow. The groove between the internal and external anal sphincter (inter-sphincteric sulcus) can be visualized or easily palpated. Distinction between internal and external anal sphincter hypertonicity can be estimated by inducing relaxation, which can usually be accomplished by prolonging the examination while talking to the patient; hyper-tonicity is most likely due to striated muscle hyperactivity. Digital examination should include a full 360-degree sweep of the rectum, including the posterior presacral hollow and the pelvic sidewalls.
During dynamic palpation, the examiner should note both the increase in anal canal tone and the mobility of the posterior loop of the puborectal muscle during squeeze. To assess the presence of paradoxical puborectalis syndrome, the patient is asked to strain while the examiner's finger is kept in the rectum. Patients with paradoxical puborectalis syndrome will squeeze and some will have intermittent contractions, rather than the Valsalva maneuver. Although the physical examination may be suggestive of paradoxical puborectalis contraction of the external anal sphincter and puborectalis, the patient's embarrassment may cause a "paradoxical reaction" and the diagnosis is usually reached only after anorectal physiology investigation. Acute localized pain triggered by pulling or compressing the border of the pub-orectalis muscle is a feature of levator spasm syndrome.
The presence of a rectocele in females can be assessed during physical examination by curving the examining finger and pressing it against the anterior rectal wall until it appears in the vagina, on the other side of the perineal body (Fig. 5.1). This anterior herniation of the rectal wall is much more common than the posterior type, particularly in females in whom the recto-vaginal septum is weakened by factors such as multiparity and traumatic vaginal delivery. Rec-toceles are found in up to 70% of asymptomatic women; therefore, care must be taken to avoid overtreating this entity, whether found during physical examination or on videodefecography. The clinical history can be highly suspicious when patients describe the need either to press the posterior vaginal wall or to do rectal digita-tion to assist defecation. Rectoceles can be found in up to 45% of patients with emptying disorders
Figure 5.1. Rectocele. From University of Sao Paolo, Sao Paolo, Brazil.
due to nonrelaxing puborectalis syndrome.43 This type of rectocele usually represents a compensatory mechanism due to the functional closure of the anal canal during attempted defecation and consequent high intrarectal pressure. This finding is of primary importance because, under these circumstances, surgical treatment of a rectocele will fail; instead, biofeedback should be indicated.
Rectal bulging as a result of an internal prolapse may present as a rectocele. Internal prolapse can be palpated by the examining finger as a descending mass during straining on digital examination. Intrarectal and rectoanal intussusception represent initial phases of rectal prolapse: a fold develops in the rectal wall during push, prolapsing into the rectum, and subsequently the intussusception descends to obstruct the anal canal, finally becoming an external prolapse. These findings must be interpreted in light of the patient's clinical history. More advanced degrees of intussusception can cause rectal pain or even lead to solitary rectal ulcer syndrome with elimination of blood or mucus through the rectum.
However, the differential diagnosis can often be made based solely on defecography, which can also determine the size of the rectocele. Moreover, by providing data on rectal emptying, defecography will allow differentiation of a secondary finding from a clinically relevant rectocele. An overt rectal prolapse or prociden-tia can be diagnosed by conducting the examination while the patient is straining on a commode.
A combined vaginal digital examination can be very helpful; with the patient in a standing position, the examiner's index finger is inserted into the rectum and the thumb is inserted into the vagina. During this examination the patient should be asked to strain. A peritoneal sac containing omentum or a loop of bowel dissecting the rectovaginal septum can be palpable between the thumb and the index finger, indicating the presence of a peritoneocele or entero-cele (Fig. 5.2). This examination can be an effective method of distinguishing among ente-rocele, vaginal vault prolapse, rectocele, or a combination of these weakened conditions. Again, defecography is a crucial method of confirming these findings and evaluating their role in the dynamics of defecation. The cul-de-sac or pouch of Douglas can eventually extend caudally between the rectum and vagina in
varying degrees even as far as the perineum and become the site of a cul-de-sac or vaginal hernia. The hernia contents can include the omentum, small bowel, and occasionally an elongated loop of sigmoid.44 Hernias are named according to their location, not their contents. Therefore, strictly speaking, the term cul-de-sac hernia is more appropriate than enterocele or sigmoido-cele. However, this latter terminology seems more discriminative and has gained wide acceptance among both colorectal surgeons and gynecologists. Concomitant urogynecologic and colorectal dysfunctions are highly prevalent in a clinical practice. Therefore, it is incumbent upon the colorectal surgeon to develop a working relationship with other clinicians for a comprehensive approach.
Cul-de-sac hernias have been classified as primary when factors such as multiparity, advanced age, general lack of elasticity, obesity, constipation, or increased abdominal pressure are present, and secondary when enteroceles follow previous gynecologic procedures, especially vaginal hysterectomy. The incidence of enterocele at 1 year or more following vaginal hysterectomy ranges from 6% to 25%, although this can be significantly reduced by obliterating the cul-de-sac with suture of the uterosacral ligaments.45
Sigmoidocele and enterocele are generally part of a complex entity known as pelvic laxity or pelvic relaxation, which results from weakened supporting tissues of the vagina and pelvic diaphragm. Several defects may coexist including anterior rectocele, rectoanal intussusception or overt rectal prolapse, cystocele, and vaginal or uterine prolapse. Therefore, the clinical relevance of a sigmoidocele or enterocele in this complex syndrome is an important issue to be considered when planning the treatment of these disorders. Consequently, symptoms of pelvic discomfort, sensation of incomplete evacuation, and prolonged straining can be more severe in patients with sigmoido-cele. Although more pronounced cul-de-sac hernias can be diagnosed during physical examination as a prolapse of the upper posterior vaginal wall during Valsalva's maneuver, more accurate assessment of this entity, especially sig-moidocele,became possible only after the advent of defecography.
Both anoscopy and proctosigmoidoscopy are useful to exclude anorectal diseases such as neoplasms, rectoanal intussusception, solitary rectal ulcer syndrome, and inflammatory bowel disease. Rigid proctosigmoidoscopy is a more accurate method of measuring the distance from the anal verge, but the average length reached is approximately 20 cm. Flexible sigmoidoscopy has a three to six times higher yield and is more comfortable for the patient. Solitary rectal ulcer syndrome is characterized by the triad of rectal discharge of blood and mucus, a lower anterior benign rectal ulcer, and disordered defecation. The nature of the ulcer is presumably traumatic due to excessive straining, and, in fact, defecog-raphy often demonstrates intussusception or paradoxical puborectalis syndrome in these patients.46
Rectal biopsy is required if Hirschsprung's disease is suspected, and less frequently, in the diagnosis of other systemic diseases such as amyloidoses. A full-thickness rectal biopsy confirms the presence or abscense of ganglionic cells in both Meissner's submubosal and Auer-bach's myenteric plexi. Based on a recent histo-logic review of cadaveric disections, the normal distance of aganglionic bowel wall is 2 cm or less from the dentate line. Therefore, it is important that the biopsy be taken 2.5 to 3.0 cm cephalad to the dentate line to avoid the short aganglionic
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Everyone has an upset stomach from time to time. You probably know the sort of thing I mean – sometimes you’ve got gas and at other times you feel queasy or nauseous. There may be times<br />when you can’t seem to go to the toilet for days, constipated as can be, but there are other days when diarrhea strikes and you can’t stop going!