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Components Separation Technique and Modifications to Improve Outcomes
131
external oblique to contralateral external oblique is a tendon repair. The onlay position also
promotes regeneration of the biologic mesh by maximizing direct contact between the mesh
and the underlying muscle. Finally, it is speculated that the onlay technique is technically
easier, risks less intraperitoneal injury, and may cause less ischemia in the fascia compared to
inset typical of inlay or underlay [den Hartog et al., 2008].
It is important to quilt the material down to the anterior abdominal wall. These quilting
sutures must only be placed over top of the rectus abdominis muscles since they are placed in
a blind fashion. This is safe so long as the rectus muscle is present. Laterally, the abdominal
wall may be too thin to safely place these sutures without risk of entering the peritoneal
space. The quilting sutures are important to place because they further offload tension from
the midline by further distributing the tension and they prevent seroma formation between the
implant material and the fascia. In addition, the quilting sutures help minimize shearing
forces.
Underlay mesh placement offers a mechanical advantage against intra-abdominal
pressure and gravity similar to patching a tire from the inside. The mesh is secured
intraperitoneally by applying full thickness U-stitches at 1 cm intervals through the mesh and
the anterior abdominal wall. The underlay position requires extensive lysis of adhesions to
clear the underside of the anterior abdominal wall of viscera. It is also important to ensure the
piece of mesh is taught against the anterior abdominal wall to prevent bulging of the mesh.
Inward bulging creates a potential space between the rectus and the mesh, decreasing the
likelihood of vascular ingrowth. The mesh is also placed posterior to the repair which offers a
layer of protection from the skin and superficial wound infections. Disadvantages risk of
visceral injury as well as muscle ischemia secondary to full thickness stitches [Afifi, 2005].
The retrorectus or retromuscular repair was first described by Stoppa in 1989. Mesh is
placed between the posterior rectus sheath and the posterior side of rectus abdominus. The
plane is entered by incising the posterior rectus sheath and dissecting it free from the
overlying muscle laterally to the psoas muscle on the both sides. This technique creates a
layer of protection from the intraperitoneal contents and is posterior to the primary repair and
the skin [Iqbal, 2007]. However, in large hernias or cases with significant muscle atrophy, this
relatively small space may allow for insufficient mesh overlap. Furthermore, significant
previous abdominal surgery can violate the layers of the abdominal wall making this plane
difficult to access.
Perforator-Sparing Technique
Perforators can be spared to increase vascular supply to the skin. The perforators of
the deep epigastric arcade supply the rectus abdominus muscle and the overlying skin in the
midline. In a classic “open” components separation, periumbilical rectus abdominus
perforators are sacrificed to create skin flaps past the semilunar lines. However, the tenuous
perfusion to the edges of the skin flips leaves the patient at high risk for superficial wound
complications. In the perforator-sparing technique, the semilunar lines are accessed via
tunnels superior and inferior the umbilicus. The tunnels are connected lateral to the
periumbilical perforators, leaving the vascular supply intact. Perforator-sparing components
separation was found to decrease wound complications from 20% to 2% compared to classic
“open” components separation without increased incidence of hernia recurrence or other
Jennifer Sabino, Jamil A. Matthews and Devinder P. Singh
132
complications such as hematoma [Saulis and Dumanian, 2002]. It is important to note that
mesh placed in the onlay position needs to be adjusted with respect to the preserved vascular
structures. This can be accomplished by making keyhole slits in the mesh to fit around the
perforators on each side. It may also be appropriate to consider an underlay mesh when
attempting a perforator-sparing components separation.
Progressive Tension Sutures
Progressive tension sutures or quilting sutures on tension help to reduce dead space,
reduce the risk for seroma by decreasing sheer forces on the skin flaps, and further off-load
midline tension in the ischemic skin flap. The difference between progressive tension sutures
and traditional quilting sutures is progressive advancement of the skin flaps towards the
midline under tension rather than simply suturing the flap down to the fascia where it lies.
Progressive tension sutures are placed toward the midline at 1 cm intervals while the tension
of the flap is maintained by the assistant. When bilateral flaps are secured at the midline,
excess skin can be excised further decreasing tissue burden and risk of necrosis at the skin
edges.
Minimally Invasive or Endoscopic Approach
Because of the aforementioned high risk of wound complications, minimally invasive
modifications to the classic “open” components separation techniques also exist which further
preserve anatomic structures and negate the need for large skin flaps. In cases without
endoscopy, incisions are made at the level 2 cm below the costal margin and the anterior
superior iliac spine over the semilunar lines. The incision is cared down to the external
oblique fascia. A tunnel is created between the two incisions over the semilunar lines. At this
point, the external oblique fascia can be excised using electrocautery 1 cm lateral to the
semilunar lines. Similar to the open technique, the fascial incision can be bluntly dissected off
the underlying muscle and extended across the length of the tunnel over a gloved finger or a
suction tip. This is accomplished best with a lighted retractor. This technique results in fewer
overall wound-healing complications compared to open components separation technique,
32% versus 14%, with no increased incidence of recurrence [Ghali et al., 2012].
Alternatively, the endoscopic approach can be used. Again, an incision is made at the
level of the anterior superior iliac spine. The space is insufflated using a laparoscopic balloon
dissector and two additional trochars are placed under direct visualization 2 cm below the
costal margin and 3 cm superior and medial to the for incision at the anterior superior iliac
spine. After hemostasis is achieved, the edge of the rectus abdominus is identified and the
external oblique fascia is incised 1 cm lateral to the semilunar line using endoscopic
electrocautery [Lowe et al., 2000].
Patients undergoing open or endoscopically assisted minimally invasive components
separation have reported higher initial success with lower complications and no difference in
recurrence [Lowe et al., 2000]. However, there is slightly less fascia advancement when a
minimally invasive approach is chosen and may not be adequate for larger defects because
skin flap elevation also facilitates advancement [Harth and Rosen, 2010]. These techniques
Components Separation Technique and Modifications to Improve Outcomes
133
are also not ideal for mesh placed in the only position because there is not an adequate
amount of overlap when skin flaps are not created.
Concurrent Panniculectomy
Additional maneuvers include excision of any redundant skin and fat. Sometimes this
requires a formal transverse panniculectomy, and sometimes it is simply a matter of debriding
several centimeters of skin and fat from each side of the incision. Concurrent panniculectomy
has been advocated to gain better access to the abdomen with the thought that reducing the
pannus may also decrease the rate of wound complications. A recent study by Zemlyak and
colleagues [2012] did not show a statistically significant different rate in wound
complications in patients who underwent concurrent panniculectomy and ventral hernia
repair. However, patients undergoing concurrent panniculectomy and ventral hernia repair did
experience a slightly higher rate of cellulitis when complications were broken down by type.
When approaching a panniculectomy that may intersect with a midline vertical incision,
it is important to plan the transverse incisons carefully. We generally believe that the
reduction of massive redundant hanging abdominal pannus promotes a better wound outcome
by decreasing the relatively ischemic fat burden. The tradeoff is a larger incisional burden in
the skin itself, but our experience has been very favorable with primary panniculectomy at the
time of midline incision when properly performed with limited undermining. Next, for the
remaining skin flaps, it is important to remove any sub-Scarpa’s fat. This is particular
important in patients with thick subcutaneous layers. This deeper fat is generally ischemic and
leaving it puts the patient at risk for fat necrosis and therefore at risk for seromas and wound
infections.
ADJUNCTIVE THERAPIES
Drains
Complex abdominal wall reconstruction often requires the creation of large flaps with
multiple planes between layers of tissue. Fluid can form between tissue planes, impairing
healing and tissue integration. Closed suction drains are placed in the majority of open ventral
hernia repairs to prevent fluid accumulation and decrease the risk of seroma formation. While
there are many studies in the literature advocating the use of drains, there is insufficient
evidence to support that the use of drains is associated with better outcomes than no drains
[Gurusamy et al., 2012].
Drain placement depends on type of repair and mesh position. In open procedures
utilizing mesh, bilateral drains are placed between the mesh and primary repair or skin flaps
for underlay and onlay mesh placement, respectively. Typically, drains are removed in the
two to four week range but sometimes the drains are left in for as long as six weeks. Our
criteria for removal include drain output less than 20 ml per drain per day for at least 2
consecutive days. Abdominal binders can also be used postoperatively or after the drains are
removed to further decrease seroma formation and increase patient comfort. However, it is
Jennifer Sabino, Jamil A. Matthews and Devinder P. Singh
134
argued that immediate placement of an abdominal binder reduces blood flow to the skin flaps
and can cause undo necrosis secondary to compression. Therefore, it may be prudent to wait
48 hours postoperatively to apply an abdominal binder.
Laser Assisted Fluorescent Imaging
In these complex cases, when the skin is often closed under some amount of tension, the
perfusion to the skin and underlying tissue is often tenuous. Current methods to verify
appropriate vascular supply to the closure most commonly rely on clinical assessment.
Identification of inadequate perfusion is often late, after complications have already
manifested. Laser-assisted fluorescence imaging uses indocyanine green dye to test perfusion.
Ten milligrams of dye is delivered into the patient's circulation, and 10 seconds later
fluorescence of the dye is stimulated by a laser within the camera head positioned over the
tissue of interest. The resulting fluorescence is recorded and an image is captured by the
computer screen. This provides real time status of tissue perfusion [Holm et al., 2002; Phillips
et al., 2012]. The results are invaluable in cases in which tissue perfusion may be
compromised, such as skin closures under tension in complex abdominal wall reconstruction.
This use of perfusion mapping helps determine precisely the demarcation line between
viability and necrosis in the skin flaps. Areas at risk of necrosis can be debrided during the
initial closure which promotes better wound healing and decreases the risk of infection.
Incisional Negative Pressure Dressing
A final maneuver that has decreased the rate of wound breakdown is the use of negative
pressure therapy dressing over the closed incision. Skin closure is obtained using an
interrupted intradermal closure with resorbable sutures. A non-adherent porous dressing is
then placed over the suture line. On top of that we place the foam and the adhesive layer and
place the dressing on negative 125 mmHg suction. It is important to note that the foam strip
should be cut approximately 3 inches wide to ensure appropriate skin overlap; a very narrow
strip will not be sufficient. This dressing draws away any drainage from the suture line, but
more importantly draws blood flow to the wound edges and reduces edema, while
mechanically pulling together the skin edges and stabilizing the suture line. This dressing is
left in place for the patient’s entire hospitalization (up to 7 days). This has remarkably
improved outcomes in even the most challenging large panniculectomy incisions.
Recent studies have shown the benefits of the application of negative-pressure therapy on
open abdominal wounds after large hernia repair. These benefits include: promoting a moist
wound healing environment; fluid evacuation and promotion of angiogenesis; minimizing
edema, maintenance of a sterile field, creation of a splint effect helping to distribute wound
tension. Overall, patients treated with this device have experienced a decrease in wound
complications such as infection, wound dehiscence, and a faster recovery. Negative pressure
wound therapy has also had favorable results on closed wounds in trauma populations
[Stannard, 2012]. Similarly, a retrospective review of patients treated with negative pressure
wound therapy at this institution the incidence of post-operative complications was 17%
Components Separation Technique and Modifications to Improve Outcomes
135
compared to a complication rate of 48% in patients treated with standard incisional care
[Condé-Green et al., 2012].
CONCLUSION
Open components separation - once reserved as an operation of last resort – is now
considered a first line therapy in the management of large ventral hernia for general and
plastic surgeons. In the last twenty years, as hernia and obesity have become epidemic in our
society, the use of this technique has rapidly proliferated amongst abdominal wall surgeons
when approaching primary ventral repair. While the technique is relatively simple, it is both
powerful and anatomically elegant. Medialization of the rectus abdominus helps to preserve
core function and decrease recurrence.
However, classic open components separation has a high rate of wound complications.
This propensity for surgical site occurrences is particularly worrisome if selecting a synthetic
mesh for reinforcement, as it may lead to synthetic mesh infection and the need to explant.
We acknowledge important modifications of component separation, such as perforator-
sparing, endoscopic, and other minimally invasive techniques. Despite these variations,
proper and careful management of the skin flaps in open components separation can still be
achieved by an accumulation of techniques including: limited undermining, indocyanine
green (ICG) angiography, debridement of ischemia in skin and fat flaps, primary
panniculectomy if indicated, progressive tension sutures, multiple drains, quilting the biologic
mesh, the use of incisional negative pressure dressings, and the avoidance of compression
binders in very early postoperative period. Excellent outcomes in both hernia recurrence rates
and wound complication rates in a very high-risk population can be achieved using
components separation with various modifications and adjunct therapies with proper
preoperative planning and postoperative care.
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In: Hernias ISBN: 978-1-62948-441-9
Editor: Mark A. Suckow © 2014 Nova Science Publishers, Inc.
Chapter 10
RICHTER’S HERNIA: CLINICAL
ASPECTS AND MANAGEMENT
Peter Bistolarides
*
and Aziz M. Merchant
2
1
Division of Surgery, Central Michigan University College of Medicine
Saginaw, Michigan, US
2
Department of Surgery, Rutgers-New Jersey Medical School
Newark, New Jersey, US
ABSTRACT
Richter’s hernias have traditionally been considered rare hernias, however, they have
become increasingly important due to the increased use of minimally invasive abdominal
surgery techniques, creating the conditions that contribute to their formation. Their
unique anatomic pathology, in many cases contributing to difficulty in or delay in
diagnosis with negative effect on morbidity and mortality, highlight the need for clinical
awareness among surgeons. This chapter reviews Richter’s hernias, their etiology, and
current diagnosis and management.
Keywords: Richter’s, etiology, diagnosis, treatment
INTRODUCTION
A Richter’s hernia is unique in that it is defined, not by anatomical location, but by the
nature of the content of the hernia - specifically the incarceration of the partial circumference
of a hollow viscus (usually small or large intestine) through a hernia orifice. Its’ perceived
rarity has traditionally relegated Richter’s hernia to periodic case reports and scant review
articles, however, this type of hernia is of increasing clinical importance due to the
pervasiveness of minimally invasive and other procedures that, although minimizing trauma
*
Corresponding author: Central Michigan University Division of Surgery, Surgical Disciplines Bldg, 912 S.
Washington, Saginaw, MI 48601 peter.bistolarides@cmich.edu.
Peter Bistolarides and Aziz M. Merchant
140
to the abdominal wall, creates sites with the potential for this type of hernia. Additionally, it
can pose a diagnostic challenge, as the typical signs and symptoms of a hernia may be absent,
leading in some cases to a dangerous delay in diagnosis with a concomitant increase in
morbidity and mortality.
HISTORY
The first known description of a Richter’s-type hernia was in 1606 by Fabricius Hildanus,
a prominent German surgeon of the late 16
th
and early 17
th
centuries [Hildanus, 1601;
Hildanus, 1646]. He described “gangrene resulting from an intestinal hernia with
perforation,” and subsequent spontaneous healing of an enterocutaneous fistula resulting from
a perforated Richter’s hernia of the inguinal region. August Gottlieb Richter, the German
surgeon of the 18
th
century whose name this hernia now bears, provided the first
comprehensive description of the Richter’s hernia in his 1785 manuscript “Treatise on the
Ruptures” [Richter, 1785], describing them as “small ruptures.” Subsequently, however, this
type of hernia was routinely called a Littre’s hernia (which is, more accurately, a hernia
containing a Meckel’s diverticulum) without special distinction related to its pathology.
The term “Richter’s hernia” was ultimately coined by Sir Frederick Treves in 1887. His
treatise on Richter’s hernia remains, over a century later, a seminal manuscript on Richter’s
hernias with respect to its clinical features, pathogenesis, and management [Treves, 1887].
Regarding Richter’s hernia, Treves stated: “…it receives no notice, and those treatises in
which it is mentioned it is usually disposed of in a few lines. The hernia is rare, but not so rare
as to be merely a curiosity”. In the many years subsequent to Treves’ paper, the perceived
rarity of Richter’s hernia appears to have relegated it to sporadic case reports and occasional
review articles.
ANATOMY
A Richter’s hernia is not confined to any particular area of the abdominal wall, but may
present through any defect or orifice in the external abdominal wall or internally. It is useful
to classify these defects as “naturally” occurring (hernia defects – including internal – that
have developed without a history of trauma) and iatrogenic (hernia defects occurring at open
incisional sites, access sites for minimally invasive procedures, and peritoneal access sites for
various catheters and tubes).
Naturally-Occurring Sites
Richter’s hernias have been classically described as occurring with the greatest frequency
in femoral and inguinal hernias [Steinke and Zellweger, 2000; Skandalakis et al., 2006],
although they have also been described in other various locations, such as the obturator
foramen and sacral foramen [Botsford, 1997], uncommon abdominal wall hernias such as