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33. Recurrent Incisional Hernia Repair
lysis of adhesions and removal of other prosthetic material; (2) creation
of a wide retrorectus plane, in which the posterior rectus sheath and
peritoneum are dissected off the posterior surface of the rectus abdominis
muscle and potentially further extended to the most lateral aspects of the
abdominal wall; (3) primary closure of the posterior rectus sheath and/or
peritoneum, to create a natural tissue barrier to avoid prosthetic contact
with the viscera; (4) placement of a widely overlapped, permanent mesh
prosthesis into the retrorectus space and securing it circumferentially;
and (5) closure of the anterior rectus sheath [ 16 ] .
This technique offers several advantages that help counteract some of
the factors that may lead to recurrence. It is done in a relative tension-
free fashion and excludes the mesh prosthesis from the viscera, reducing
the potential for mesh infection and fi stula formation. The retrorectus
space is well vascularized, and the size of the space allows for a huge
surface area for tissue ingrowth into the mesh. Finally, it theoretically
allows the mesh to augment the strength of the abdominal wall when
intra-abdominal pressure increases since the mesh lies deep to the
anterior fascia [ 17 ] .
Data supporting the use of this approach for recurrent incisional
hernias are included in larger series of open Stoppa repairs for all
incisional hernias. The Mayo Clinic series of 254 patients with complex
incisional hernias repaired using this technique included 76 patients with
recurrent hernias, some multiply recurrent. The majority of these hernias
were midline incisional hernias, and most were repaired using
polypropylene mesh. Overall hernia recurrence with mean follow-up of
70 months was 5%, though this was for the entire cohort, not just recurrent
hernias. Interestingly, recurrence was much more common in patients
who had wound infections [ 17 ] . Novitsky et al. published a series of 32
patients who underwent repair of multiply recurrent incisional hernias
with open preperitoneal technique. Over half the patients were morbidly
obese, and comorbidities such as diabetes, pulmonary disease, and
smoking were common. Again, polypropylene mesh was used with very
large surface area for ingrowth (mean 937 cm [ 2 ] ). Mean follow-up of
28 months yielded only a single recurrence, occurring in a patient who
required partial mesh removal due to infection. In their discussion, the
authors stress the advantage of wide mesh overlap, which in some cases
measured 8–10 cm [ 18 ] . Another series with mean follow-up of
34 months included 15 recurrent hernias repaired with modi fi ed Rives-
Stoppa technique; only 1 recurrence occurred in a patient requiring mesh
removal for infection [ 19 ] .
392
J.G. Linn and D.J. Mikami
There are drawbacks to this approach, however. The retromuscular
dissection can be bloody, and it creates a large space which can be a
source of hemorrhage in the early postoperative period. Additionally, the
neurovascular innervation to the muscles of the abdominal wall lies just
lateral to the rectus muscle, and signi fi cant long-term morbidity can
result if this is injured. An earlier series reported high long-term
postoperative pain scores in a signi fi cant proportion of patients, occurring
in up to 27%. The use of slowly absorbing sutures may help minimize
this potential complication.
Laparoscopic Recurrent Incisional Hernia Repair
Laparoscopic incisional hernia repair was introduced in the 1990s
with the potential advantages of smaller incisions, less postoperative
narcotic use, shorter hospital stay, and faster return to normal activity
compared to open repair [ 20, 21 ] . The laparoscopic repair is performed
with 3–5 ports placed on the lateral aspect of the abdominal wall. Once
adhesiolysis and hernia reduction are completed, the mesh is inserted
through a port and af fi xed to the abdominal wall. This can be achieved in
a number of ways, with transfascial sutures, tacking devices, and adhesive
sealants. This offers the same theoretical advantage as the Stoppa repair,
with the mesh placed posterior to the abdominal wall as an augmentation.
It also allows the surgeon to visualize the entire abdominal wall,
preventing the potential for missed hernias described by Wassenaar [ 14 ] .
It allows a potentially more accurate estimation of mesh overlap at the
edges of the defect, which may help prevent the “edge of the mesh”
recurrences described by Awad.
Several series of laparoscopic repair of recurrent incisional hernia
have shown durability of the repairs at intermediate follow-up. Verbo
and colleagues published a series of 41 recurrent hernias repaired using
PTFE mesh. Patients underwent clinical exam and ultrasound examination
at 6 and 12 months postoperatively, and only 1 recurrence was identi fi ed
at mean follow-up of 38 months [ 22 ] . A prospective study by Uranues
showed only three recurrences in 85 patients undergoing laparoscopic
repair of multiply recurrent hernias with mean follow-up of 41 months.
Interestingly, patients were followed with health-related quality of life
scoring 2 years after surgery, and scores were signi fi cantly improved
[ 23 ] . Both series included patients with larger hernias, and many had
prior mesh repairs.
393
33. Recurrent Incisional Hernia Repair
The question of superiority between laparoscopic and open recurrent
incisional hernia repairs has not been borne out in the literature. Bingener
compared two cohorts of patients undergoing laparoscopic incisional
hernia repair to a group of patients undergoing open mesh onlay , which
showed equivalent recurrence at long-term follow-up. Patients undergoing
open repair had twice the rate of major morbidity as patients in the
laparoscopic cohort [ 24 ] . A meta-analysis of randomized controlled trials
comparing laparoscopic and open repair of any incisional hernia, not only
recurrent hernias, showed no signi fi cant difference in recurrence rate
between the two approaches. Laparoscopic hernia repair had a relative
risk = 0.22 of wound infection compared to open repair. There was also a
trend toward decreased mesh infection and bleeding complications with
the laparoscopic approach [ 25 ] . An earlier series from the Cleveland
Clinic showed similar recurrence rates for laparoscopic and open hernia
repairs; however, patients who required conversion to open repair from a
laparoscopic attempt had signi fi cantly higher recurrence. It is important
to note the follow-up period in this study was 5 years, and the 25–30%
overall recurrence rate after mesh repair may be a more accurate estimation
of long-term recurrence with either technique [ 26 ] .
Re fi nements to the technique of laparoscopic hernia repair may help
reduce recurrence rates in these complex hernias. A major difference
between the laparoscopic and open repairs is that open repair usually
involves closure of the fascia anterior to the mesh underlay, which
increases the surface area for potential mesh ingrowth and adds another
barrier to mesh infection. Traditionally, laparoscopic hernia repair has
not included primary closure of the fascial defect with mesh underlay.
Some data suggests that this may reduce recurrence rate compared to
standard techniques; this also creates a greater surface area for
laparoscopic mesh fi xation to the fascia, preventing mesh migration [ 27,
28 ] . Laparoscopic approaches to recurrent incisional hernias will likely
continue to increase in utilization, and other technical considerations
may help prevent recurrence.
Component Separation
While laparoscopic and open Stoppa repairs of recurrent incisional
hernias rely heavily on prosthetic augmentation of the abdominal wall,
autologous tissue closure of large, midline incisional hernia defects can
be accomplished with abdominal wall component separation. This repair
can be extremely valuable in patients with obvious contraindication to
394
J.G. Linn and D.J. Mikami
synthetic mesh placement, such as in contaminated fi elds. Synonymous
techniques include “separation of parts,” “bilateral myofascial release,”
and “sliding myofascial fl ap.” Described by Ramirez in 1990, this
technique allows a surgeon to increase the volume of the abdominal
cavity by transposing the muscle layers of the abdominal wall while
preserving neurovascular supply.
For recurrent incisional hernia repair that likely involves visceral
adhesions, this technique requires several steps: (1) the abdomen is
entered through a midline incision and a complete lysis of adhesions
is performed; (2) the lateral most aspect of the rectus abdominis muscle is
palpated; (3) the skin and subcutaneous fat are elevated from the anterior
fascia, taking care to preserve the perforating branches of the epigastric
and circum fl ex iliac vessels; (4) the external oblique aponeurosis is
incised 2 cm lateral to the rectus muscle border and carried cranially to
the costal margin, then caudally to the iliac crest; (5) the external and
internal oblique muscles are bluntly separated from one another, allowing
a release of the external layer so the rectus muscle may be advanced,
tension-free, to the midline; (6) the same steps are repeated on the
opposite side. This allows for advancement of the rectus muscle 3–5 cm
in the upper abdomen, 7–10 cm in the mid abdomen, and 1–3 cm in the
lower abdomen. If additional release is required, the posterior sheath can
be separated from the rectus muscle, though this increases the risk of
lateral abdominal wall defects postoperatively [ 29 ] . This allows closure
of defects up to 15–20 cm in the midline with the standard approach,
though other authors would dispute that such a large degree of
mobilization is routinely achieved [ 30 ] .
Results of component separation for recurrent incisional hernia
should be considered in light of the types of hernias for which the
technique is usually applied: very large, multiply recurrent hernias in
challenging patients that may involve removal of other mesh prostheses
or skin-graft removal. DiBello published a series of 35 patients with
large (>10 cm), recurrent incisional hernias repaired with component
separation and selective mesh underlay. Mean follow-up of 22 months
yielded a recurrence rate of 9% [ 31 ] . Another retrospective cohort study
of 284 patients with recurrent hernias demonstrated a recurrence rate of
22% in hernias repaired with component separation [ 32 ] .
While these results are very good for large, recurrent incisional
hernias, the operation carries signi fi cant risk of wound complications
due to the large subcutaneous space created by the super fi cial dissection,
which may predispose patients to infection. A series from the Netherlands
demonstrated a 32% wound complication rate in 43 patients undergoing
395
33. Recurrent Incisional Hernia Repair
component separation for large incisional hernias [ 33 ] . A modi fi cation
of the midline-subcutaneous dissection technique, popularized by
Dumanian and others, avoids the creation of these large subcutaneous
fl aps. Instead, 6–8-cm transverse incisions are created at the anterior
axillary line just below the costal margin. With the assistance of long,
narrow retractors, the external oblique muscle is divided adjacent to the
semilunar line, and this is carried from the costal margin to the iliac crest
[ 34 ] . This allows preservation of the perforator blood supply to the skin
and subcutaneous fat, which is particularly important in patients who
have undergone prior stoma creation, which interrupts abdominal wall
blood supply [ 29 ] . Others have used a combined endoscopic-open
approach to component separation. This uses two or three trocars placed
on either lateral abdominal wall. Using a technique similar to totally
extraperitoneal laparoscopic inguinal hernia repair, the external oblique
is incised, and the space between the external and internal oblique layers
is balloon dissected. The external oblique fascia is divided vertically as
with open component separation, and the dissection is repeated on the
contralateral side [ 30, 35 ] . This may offer some bene fi t to standard open
fascial release, but probably does not offer signi fi cant advantage over the
technique that uses bilateral transverse incisions.
The use of mesh underlay for augmentation may provide additional
value in combination with component separation. Some authors advocate
the use of a dual-sided mesh such as PTFE or a coated polyester mesh
placed intra-abdominally [ 31 ] . Others will place soft polypropylene
intra-abdominally with omental coverage of the viscera [ 34 ] . One series
showed zero recurrences with soft polypropylene mesh underlay in 18
patients at 1-year follow-up [ 34 ] .
Special Techniques
Repair of recurrent incisional hernias in challenging patient
populations, such as the morbidly obese, deserves special attention.
These patients are more likely to develop primary incisional hernias, and
recurrence rates after incisional hernia repair in the obese are higher than
in lean patients [ 5, 36 ] . While the lofty goal of signi fi cant weight loss
prior to elective hernia repair is admirable, the success and compliance
with this plan is probably suboptimal. Wound complications after
infraumbilical hernia repair are dif fi cult to prevent, and removal of the
redundant skin and subcutaneous fat over the infraumbilical abdomen
during recurrent hernia repair may improve wound complication rates.
396
J.G. Linn and D.J. Mikami
Given the association between wound complications, mesh infection,
and hernia recurrence, consideration of this technique should be given to
obese patients with lower midline incisional hernias. A series of 24
component separation hernia repairs combined with panniculectomy in
obese patients showed four recurrences at 1 year [ 37 ] . In another study,
a retromuscular mesh repair combined with a panniculectomy in 47
patients for repair of recurrent incisional hernias produced a recurrence
rate of 8% [ 38 ] . However, others have demonstrated a signi fi cantly
higher rate of wound complications with panniculectomy [ 39 ] . We would
suggest that this combined approach to recurrent hernia repair with
pannus removal should be carefully applied in select patients who will
derive the greatest bene fi t from it.
Summary
Recurrent incisional hernias continue to be a challenging problem for
both patients and surgeons. While the use of prosthetic material for
nearly all recurrent hernias and advances in the knowledge of
pathophysiology of hernia recurrence have helped reduce both recurrence
rates and operative morbidity, a signi fi cant number of patients will
unfortunately suffer yet another recurrent hernia. Basic investigation into
the molecular mechanisms behind hernia recurrence will continue.
Careful attention to the factors that lead to these recurrences may help in
the planning of future operations. Re fi nements in surgical technique will
continue to evolve. We remain optimistic that these advances will help
our understanding of the appropriate treatments for recurrent hernias,
reducing both the morbidity and the rate of recurrence.
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11. Rosch R, Lynen-Jansen P, Junge K, et al. Biomaterial-dependent MMP-2 expression in
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13. Klinge U, Conze J, Krones CJ, Schumpelick V. Incisional hernia: open techniques.
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16. Temudom T, Siadati M, Sarr MG. Repair of complex giant or recurrent ventral hernias
by using tension-free intraparietal prosthetic mesh (Stoppa technique): lessons learned
from our initial experience ( fi fty patients). Surgery. 1996;120:738–43. discussion 43–4.
17. Iqbal CW, Pham TH, Joseph A, Mai J, Thompson GB, Sarr MG. Long-term outcome
of 254 complex incisional hernia repairs using the modi fi ed Rives-Stoppa technique.
World J Surg. 2007;31:2398–404.
18. Novitsky YW, Porter JR, Rucho ZC, et al. Open preperitoneal retrofascial mesh repair
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19. Bauer JJ, Harris MT, Gor fi ne SR, Kreel I. Rives-Stoppa procedure for repair of large
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23. Uranues S, Salehi B, Bergamaschi R. Adverse events, quality of life, and recurrence
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abdominal wall function. J Gastrointest Surg. 2010;14:175–85.
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B.P. Jacob and B. Ramshaw (eds.), The SAGES Manual of Hernia Repair,
DOI 10.1007/978-1-4614-4824-2_34,
© Springer Science+Business Media New York 2013
34. Chronic Mesh Infections
Andrei Churyla and Andrew B. Lederman
The use of synthetic mesh has become the standard for repair of many
types of hernias since mesh repairs have signi fi cantly lower rates of
hernia recurrence [ 1– 3 ] . However, with the use of synthetic meshes
comes the risk of infection. While the majority of mesh infections are
acute infections, presenting either early in the postoperative period or as
delayed infections, chronic mesh infections may also develop.
Chronic mesh infections can result from various clinical scenarios.
Often chronic infections result from untreated or incompletely treated
acute infections or from attempts at mesh salvage when acutely infected.
While mesh explantation is the primary treatment for acute mesh
infection, attempts at mesh salvage via antibiotics and percutaneous
drainage, dressing changes, or negative pressure wound therapy may
result in chronic infection.
Presentation
Synthetic mesh can harbor bacteria and may present as an indolent
infection several years after implantation [ 4, 5 ] . Chronic mesh infections
may present without an acute phase, as a chronic non-healing wound,
sinus tract, or a wound with cycles of spontaneous closure followed by
wound dehiscence and drainage. Sinus tracts or associated enterocutaneous
fi stulae tend to be very low output and may even appear to heal only to
spontaneously drain in the future.
Diagnosis is usually based on a history of mesh implantation and the
presence of an associated chronic wound. A history of postoperative
wound infection, previous mesh infections, or sepsis should raise a
suspicion of mesh infection. Systemic signs of infection are variable.
Fever, leukocytosis, elevated erythrocyte sedimentation rate or other
400
A. Churyla and A.B. Lederman
markers of in fl ammation are unreliable indicators of chronic mesh
infection. Imaging with CT scan, white blood cell nuclear medicine scan,
or sinogram may be useful to demonstrate in fl ammation or fl uid around
mesh, but the diagnostic yield is variable. The best diagnostic test is
usually to probe an open wound with a cotton swab or fi nger, often
making the diagnosis by palpating the rough edge of exposed mesh.
Percutaneous drainage of suspected infections or fl uid collections might
prove infection, but also introduce the risk of infecting a potentially
sterile mesh; drainage is more useful as a therapeutic maneuver for
known infections rather than a diagnostic test.
Biomaterials
The type of mesh may in fl uence the risk of developing chronic
infections. The ability of bacteria to adhere to mesh is affected by the
surface area of the mesh, the hydrophilic or hydrophobic nature of the
material, and the pore size of the mesh. Additionally, mesh coatings and
composite meshes made of more than one type of material also in fl uence
the potential for infections.
Multi fi lament meshes, typically made from polypropylene, have a
signi fi cantly greater surface area for bacterial adherence and may be
more prone to infection. This results in a higher rate of fi stula formation
and persistence of bacteria when attempts are made to salvage mesh
[ 6, 7 ] . Mono fi lament mesh limits the adherence of bacteria and may be
less prone to chronic infection.
Microporous mesh, such as PTFE or ePTFE with a pore <10 m m, will
allow adherence of bacteria, but the pores are too small to admit
leukocytes. This small pore size limits the propensity to form adhesions
but increases the risk of infection. When mesh gets infected, microporous
mesh generally cannot be salvaged since infection cannot be cleared
through immune response. In contrast, macroporous prostheses, typically
polypropylene or polyester, allow for ingrowth of fi broblasts,
macrophages, and collagen fi bers. While this ingrowth may limit the risk
of infection, it increases mesh contraction with scar formation. Although
macroporous mesh may have a lower risk of infection, the higher risk of
adhesion formation, erosion, and fi stula formation make it a poor choice
inside the peritoneum.
Composite mesh such as combination ePTFE and polypropylene
presents a different problem. The different components stimulate a