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410 The ASCRS Manual of Colon and Rectal Surgery
B. Cecal Volvulus
Incidence and Epidemiology
• Worldwide, cecal volvulus accounts for 40–60% of all colonic
volvuli.
• It remains, however, an uncommon cause of intestinal
obstruction.
• Most reported cases occur in younger individuals with a predilection for females.
Pathogenesis/Etiology
• True cecal volvulus is actually an axial torsion of the cecum,
terminal ileum, and ascending colon about its mesentery
(Fig. 19.1A ).
• A variant, cecal bascule (Fig. 19.1B ), occurs when the cecum
folds anteriorly over the ascending colon without an axial
twist. This represents approximately 10% of cases of cecal
volvulus.
• There is a high rate of prior abdominal operations in patients
who subsequently develop cecal volvulus, and previous surgery has been considered to be a potential causative factor.
ba
Fig. 19.1. ( a ) Schematic illustration of a cecal volvulus. ( b ) Schematic illustra-
tion of a cecal bascule.
19. Colonic Volvulus 411
• A clear prerequisite is a mobile cecum and ascending colon.
A congenital component involves lack of fi xation of the right
colon, which then assumes an intraabdominal position.
• Prior abdominal surgery with colonic mobilization, recent surgical manipulation, adhesion formation, congenital bands, distal colonic obstruction, pregnancy, pelvic masses, extremes of
exertion, and hyperperistalsis have all been implicated.
• During abdominal surgery, excessive mobilization or manipulation of the cecum and ascending colon or placement/
withdrawal of packs may precipitate postoperative volvulus.
Previous reports of cecal volvulus reveal that 30–70% of
patients had undergone prior surgery.
• Displacement of the cecum by an enlarged uterus or pelvic
mass may also promote volvulus. In fact, several series report
that 10% of patients with cecal volvulus are pregnant at the
time of presentation.
Clinical Presentation
• Symptoms and signs of cecal volvulus are that of small bowel
obstruction. The majority of patients present with abdominal
pain, distention, constipation, nausea, and vomiting.
• The presentation may be that of an acute obstruction or one of
an intermittent or recurrent pattern.
• Acute volvulus results in a closed loop cecal obstruction and
distal small bowel obstruction. This may progress to a more
fulminant presentation when ischemia and gangrene develop.
Diagnosis
• The diagnosis is most often made on the basis of the combination of clinical presentation and plain abdominal fi lms or
barium enema.
• Plain fi lms may identify the classic coffee bean deformity
directed toward the left upper quadrant (Fig. 19.2A ). Barium
enema may reveal a “bird’s beak” or column cut-off sign in the
right colon (Fig. 19.2B ).
• Although barium enema is of clear value when the diagnosis
is in question, in obvious cases, performance of this study may
needlessly delay surgical therapy. It therefore should not be
routinely used.
412 The ASCRS Manual of Colon and Rectal Surgery
a
b
Fig. 19.2. ( a ) Plain abdominal X-ray of a cecal volvulus with a “coffee bean”
deformity evident in the left upper quadrant. ( b ) Barium enema study of a cecal
volvulus revealing a bird’s beak deformity.
19. Colonic Volvulus 413
Treatment/Outcome
• Laparotomy remains the primary treatment modality for cecal
volvulus.
• Both radiographic and endoscopic reduction have been
reported. Whereas radiographic attempts at reduction are generally believed to carry a high risk of perforation, other modalities have been used as temporizing measures.
• Although signifi cantly less effi cacious than in the treatment of
distal volvulus, colonoscopic reduction of cecal volvulus has
been reported with some success.
• The relatively high rates of ischemic changes found with
cecal volvulus has tempered enthusiasm for non-operative
detorsion.
• In general, the majority of individuals undergo surgical intervention with a clear diagnosis of cecal volvulus, for complete
bowel obstruction, or for an acute surgical abdomen.
• When viable bowel is encountered, although resection is the
preferred option, other alternatives exist. These include detorsion alone or combined with some fi xation procedure. Fixation
options include cecopexy and/or cecostomy. Appendicostomy
has also been reported.
• Generally, fi xation is accomplished by cecopexy and/or
cecostomy. Cecopexy is performed by elevating a lateral
peritoneal fl ap along the entire length of the ascending
colon, and suturing the fl ap to the serosa of the anterior
colonic wall, thereby placing the ascending colon in a partially retroperitoneal location, and eliminating the excess
mobility (Fig. 19.3 ).
• An advantage of tube cecostomy is that it not only anchors the
cecum, but also provides a vent for the distended colon.
• Cecopexy, and cecostomy all carry similar recurrence rates of
12–14%
• Resection, however, carries virtually no risk of recurrence and
is not associated with a higher rate of postoperative complications when compared with cecopexy alone.
• After resection, primary anastomosis can usually be safely performed. However, in the face of gangrenous bowel, end ileostomy may be a safer procedure.
414 The ASCRS Manual of Colon and Rectal Surgery
Fig. 19.3. Colopexy and cecostomy for cecal volvulus.
C. Transverse Colon Volvulus
Incidence and Epidemiology
• Volvulus of the transverse colon is an exceptionally rare fi nding. It is estimated to represent from 1 to 4% of all forms of
colonic volvulus
• This form of volvulus tends to occur more often in the young,
with most series showing a peak incidence in the second
through fourth decades of life. There is a twofold to threefold
female predominance.
Pathogenesis/Etiology
• Although anatomic factors are key to the development of
transverse colon volvulus, physiologic, rather than congenital,
19. Colonic Volvulus 415
factors seem to have a crucial role in the development. These
patients frequently have a history of chronic constipation and/
or laxative abuse, previous abdominal surgery, a diet high in
fi ber, recurrent distal obstruction, and institutionalization.
• Specifi c factors that may increase the risk of occurrence are a
redundant or elongated transverse colon with narrow mesenteric
attachments, narrowed distance between the fl exures, and an
absence or paucity of fi xation of the mesentery.
Clinical Presentation
• Transverse colon volvulus presents as a large bowel
obstruction.
• Presentation may be as a subacute recurring process or may
take a more fulminant course.
• The diagnosis is therefore usually made at the time of
exploration.
• Plain fi lms may reveal a distended proximal colon with decompressed distal bowel and two distinct air-fl uid levels representing two limbs of the volvulized transverse colon. This has been
described as a bent inner-tube appearance with the apex pointing inferiorly.
• Barium contrast studies, if performed, will demonstrate a bird’s
beak deformity at the distal transverse colon.
Treatment/Outcome
• Although successful endoscopic decompression has been
reported, surgical intervention is the recommended treatment
modality.
• Based on literature from surgical detorsion, it is assumed
that endoscopic treatment will lead to a high rate of recurrence, and may therefore be best reserved for those high-risk
individuals who show no signs of compromised bowel. However, colonoscopy may serve to confi rm intestinal viability
and allow for a less emergent defi nitive procedure to be performed.
• Operative procedures include detorsion with or without colopexy, and resection.
• Most authors recommend either segmental transverse colectomy or extended right colectomy as defi nitive treatment.
416 The ASCRS Manual of Colon and Rectal Surgery
• Clearly, in the presence of nonviable bowel, resection is
mandatory.
• As in cecal volvulus, the decision regarding primary anastomosis versus diversion is made during surgery, taking into
account the severity of the disease process and the patient’s
overall condition.
• When viable bowel is encountered, several different colopexy
procedures have been reported. These include suture of the
greater omentum, transverse mesocolon, or transverse colon
itself to the anterior abdominal wall and/or pelvis, and the
U colopexy reported by Mortensen. In this procedure, after
reduction and needle decompression of the volvulus, the
redundant U-shaped loop of transverse colon is sutured to the
adjacent limbs of ascending and descending colon (Fig. 19.4 ).
• Recurrence from either detorsion or colopexy has been reported
to range from 30 to 75%, whereas resection eliminates virtually
all risk of recurrence. Mortality, however, from resection has
been reported to be as high as 33%.
Fig. 19.4. Parallel coloplasty as described by Mortensen. 31
19. Colonic Volvulus 417
D. Splenic Flexure Volvulus
Incidence and Epidemiology
• Volvulus of the splenic fl exure of the colon is the rarest form of
colonic volvulus. It is estimated to represent 1–2% of all cases
of colonic volvulus.
Pathogenesis/Etiology
• The infrequency of this form of volvulus is believed to be the
result of multiple attachments of the splenic fl exure, and the
retroperitoneal position of the descending colon.
• Up to two-thirds of patients have had prior abdominal surgery.
Clinical Presentation
• As in transverse colon volvulus, the presentation may be acute
and fulminant, or a more chronic or subacute event.
• Four features have been described radiographically that may
suggest splenic fl exure volvulus:
– A markedly dilated air-fi lled colon with an abrupt termi-
nation at the splenic fl exure;
– Two widely spaced air-fl uid levels, one in the cecum and
the other in the transverse colon;
– An empty descending and sigmoid colon;
– A bird’s beak obstruction at the splenic fl exure on con-
trast enema examination (Fig. 19.5 ).
Treatment/Outcome
• Although colonoscopic and fl uoroscopic decompression have
been reported, most reports have identifi ed surgery as the primary
mode of management.
• However, the recurrence rate after detorsion alone, whether
performed surgically, endoscopically, or fl uoroscopically, is
approximately 20–25%.
• As a result of these high recurrence rates, nonoperative decompression/detorsion should be reserved for extremely high-risk
patients who are not candidates for surgical intervention, or as a
temporizing measure before a semi-elective defi nitive resection.
418 The ASCRS Manual of Colon and Rectal Surgery
Fig. 19.5. Barium enema study of a chronic splenic fl exure volvulus. Arrows
indicate the point of rotation and bird’s beak deformity.
• Surgical options include resection with or without stoma formation, or detorsion with or without colopexy.
• Segmental resection may be considered; however, the majority of these patients will have an associated redundant, dilated
colon and a history of chronic constipation. Therefore, these
patients may be better served by undergoing an extended resection with an ileosigmoid or ileorectal anastomosis.
• Stomas should be reserved for cases involving gangrenous
bowel with perforation and peritoneal contamination, or for
other high-risk cases.
E. Sigmoid Volvulus
Incidence and Epidemiology
• Although it is the most common form of volvulus seen, volvulus of the sigmoid colon is not very common in the United
States and Western Europe, accounting for less than 10% of all
cases of large bowel obstruction.
• In some regions of Asia, Africa, and other less-developed portions of the world, however, the situation is signifi cantly different.
19. Colonic Volvulus 419
In these areas, sigmoid volvulus accounts for 20–50% of all
the cases of intestinal obstruction.
• Overall, there is a substantial male predominance, especially
in developing nations. However, sigmoid volvulus is the most
common cause of intestinal obstruction in pregnancy, accounting for nearly 45% of all intestinal obstructions in this group of
women.
• The reasons for geographic differences in incidence are
thought to be primarily related to diet. In the West, relatively
lower amounts of fi ber are consumed, resulting in a much
higher incidence of colorectal cancer and diverticular disease,
which are the more common etiologies for colonic obstruction in these areas.
Pathogenesis/Etiology
• Any condition that results in an elongated colon predisposes to the
development of volvulus. In order for volvulus of any part of the
intestinal tract to occur, there must be a long redundant, mobile
segment, with a relatively narrow mesenteric attachment, such
that the sites of fi xation at each end are relatively close together.
• The sigmoid colon is the ideal location for this confi guration:
the sigmoid can be extremely redundant and mobile and the sites
of fi xation at the descending-sigmoid junction and the rectosigmoid junction are often in close proximity to each other.
• In the West, the typical patient with sigmoid volvulus is an elderly institutionalized male, often receiving psychotropic medications, who is usually extremely constipated. Other factors
that have been implicated are laxative abuse, previous abdominal surgery, and diabetes.
• Gross features of the sigmoid colon include progressive widening and eventual loss of taenia coli, absence of appendices
epiploicae, and a thickened narrowed fi brous mesentery.
• The rotation may be either clockwise or counterclockwise.
Once the rotation has reached 360 degrees, a closed loop obstruction occurs.
• Hyperperistalsis and fl uid secretion into the closed loop add
to increased pressure and tension. Eventually, as blood fl ow is
compromised, ischemia and necrosis develop.
• In the face of a competent ileocecal valve, perforation is more
common in the cecum.
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