Open Mesh versus Laparoscopic Mesh Repair of Inguinal Hernia
Leigh Neumayer, M.D., Anita Giobbie-Hurder, M.S., Olga Jonasson, M.D., Robert Fitzgibbons, Jr., M.D.,
Dorothy Dunlop, Ph.D., James Gibbs, Ph.D., Domenic Reda, Ph.D., and William Henderson, Ph.D.,
for the Veterans Affairs Cooperative Studies Program 456 Investigators*
Background
Repair of inguinal hernias in men is a common surgical procedure, but the most effective
surgical technique is unknown.
Methods
We randomly assigned men with inguinal hernias at 14 Veterans Affairs (VA) medical
centers to either open mesh or laparoscopic mesh repair. The primary outcome was
recurrence of hernias at two years. Secondary outcomes included complications and
patient-centered outcomes.
Results
Of the 2164 patients who were randomly assigned to one of the two procedures, 1983
underwent an operation; two-year follow-up was completed in 1696 (85.5 percent).
Recurrences were more common in the laparoscopic group (87 of 862 patients [10.1
percent]) than in the open group (41 of 834 patients [4.9 percent]; odds ratio, 2.2;
95 percent confidence interval, 1.5 to 3.2). The rate of complications was higher in the
laparoscopic-surgery group than in the open-surgery group (39.0 percent vs. 33.4 percent;
adjusted odds ratio, 1.3; 95 percent confidence interval, 1.1 to 1.6). The laparoscopic-
surgery group had less pain initially than the open-surgery group on the day of
surgery (difference in mean score on a visual-analogue scale, 10.2 mm; 95 percent confidence interval, 4.8 to 15.6) and at two weeks (6.1 mm; 95 percent confidence interval, 1.7 to 10.5) and returned to normal activities one day earlier (adjusted hazard ratio for a shorter time to return to normal activities, 1.2; 95 percent confidence interval, 1.1 to 1.3). In prespecified analyses, there was a significant interaction between the surgical approach (open or laparoscopic) and the type of hernia (primary or recurrent)(P=0.012). Recurrence was significantly more common after laparoscopic repair than after open repair of primary hernias (10.1 percent vs. 4.0 percent), but rates of recurrence after repair of recurrent hernias were similar in the two groups (10.0 percent and 14.1 percent, respectively).
Conclusions
The open technique is superior to the laparoscopic technique for mesh repair of primary
hernias.
Surgical repair of inguinal hernias
is a common procedure in adult men. However,
recurrence of hernias has been reported
to occur after repair in 15 percent or more cases, and
postoperative pain and disability are frequent.
1-5
When traditional surgical methods are used, outcomes
after repair of recurrent hernias have been
worse than after primary repair.
6,7
After the introduction
of tension-free surgical repair with the use
of prosthetic mesh, recurrence rates were reported
to be less than 5 percent, and patients’ comfort was
reported to be substantially improved over that obtained
by the traditional, tension-producing techniques.
8,9
Local anesthesia is used, and patients are
discharged within a few hours. A laparoscopic
method of performing a tension-free repair has subsequently
been reported to result in low recurrence
rates and to be associated with substantially less
pain in the immediate postoperative period and
earlier return to normal activities than the open repair
technique.
10,11
The laparoscopic technique,
however, requires general anesthesia, and it is more
often associated with serious intraoperative complications
than is open repair,
11-13
although such
complications are infrequent.
We conducted a multicenter, randomized trial
to compare recurrence rates and other outcomes
after either of two standardized tension-free herniorrhaphies:
open repair and laparoscopic repair.
METHODS
STUDY POPULATION, RECRUITMENT, STUDY INTERVENTIONS and FOLLOW-UP
Men presenting to general-surgery clinics at 14
Veterans Affairs (VA) medical centers who were
18 years of age or older, had a diagnosis of inguinal
hernia, and gave written informed consent were eligible
for random assignment to open tension-free
repair or laparoscopic tension-free repair. Patients
in American Society of Anesthesiologists (ASA)
class IV (i.e., those who had systemic disease that
is a constant threat to life) or class V (i.e., those who
were unlikely to survive for 24 hours, with or without
an operation)
14
were excluded, as were those
who had contraindications to general anesthesia,
bowel obstruction, bowel strangulation, peritonitis,
bowel perforation, local or systemic infection, contraindications
to pelvic laparoscopy, a history of repair
with mesh, or a life expectancy of less than two
years. Patients who were participating in another
trial were also excluded. Randomization was carried
out by a computer-generated, permuted-block sequence
and was stratified according to the type of
hernia (primary or recurrent), whether the hernia
was unilateral or bilateral, and the study site (the
VA medical center). In patients with bilateral hernias,
both sides were repaired simultaneously; one
side was chosen randomly by the coordinating
center to be the “study” hernia to be included in the
intention-to-treat analysis. The protocol was approved
by the human-rights committee of the Hines
VA Cooperative Studies Program and by the institutional
review board at each site. Details of the study
design can be found in a previous report.15
All the patients underwent standardized repairs
by attending surgeons who had performed (and
documented) 25 open or 25 laparoscopic repairs in
order to qualify to perform the open or the laparoscopic
procedure, respectively.
16,17
The participating
surgeons’ self-reported experience was recorded
at the beginning of each operation. The surgeons
agreed to follow a precise protocol, including pretrial
submission of a videotaped laparoscopic procedure
that was reviewed by a surgeon member of
the study’s executive committee. The presence of the
attending surgeon at the operating table throughout
the procedure was required. The open procedure
was performed according to the Lichtenstein
method, as described by Amid.
18
Laparoscopic repairs
were performed either by a transabdominal
preperitoneal approach or by a totally extraperitoneal
approach.
19-22 All repairs involved the use of
mesh. Recurrent hernias were repaired by the same
standardized procedures as were primary hernias.
All the patients were given standardized postoperative
instructions that did not restrict their activities
unless the activities caused pain.
DETERMINATION OF THE PRIMARY OUTCOME
The primary outcome of the trial was recurrence of
a hernia within two years after the repair. The patients
were followed for a minimum of two years.
Postoperatively, each patient was examined at two
weeks, at three months, and yearly thereafter to
determine the presence or absence of recurrence
by a surgeon who had not been involved in that patient’s
operation. Recurrences were confirmed by
examination by an independent surgeon, by ultrasound
examination, or during a second operation.
A patient with bilateral hernias who had a recurrence
on the side opposite the side of the study hernia
was considered not to have had a recurrence in
the intention-to-treat analysis.
DETERMINATION OF THE SECONDARY OUTCOME
Secondary outcomes were complications, death,
and patient-centered outcomes. Complications
were assessed intraoperatively and at specified intervals
postoperatively. Long-term complications
were assessed at the three-month and annual visits.
Life-threatening complications were defined before
the start of the study and were assessed for 30 days
after the procedure. All deaths and life-threatening
complications were reviewed by an independent
end-points committee to determine whether the
event was related to the operation.
Patient-centered outcomes (pain, functional status,
and activity levels) were assessed at baseline,
two weeks, three months, six months, and yearly
thereafter. Pain was assessed with the use of a visualanalogue
scale on the day of the operation and daily
until the first postoperative visit (at two weeks).
23
Functional status was assessed with the Medical
Outcomes Study 36-item Short-Form General
Health Survey (SF-36) questionnaire, version 2.
24
ORGANIZATION AND MONITORING
Each site was visited by the principal investigator
or coprincipal investigator during the first few
months of the study to ensure compliance with
study protocols. Deaths and life-threatening complications
were determined to be related or unrelated
to the treatment by an independent committee
consisting of a surgeon, an anesthesiologist, and
a pathologist.
STATISTICAL ANALYSIS
The study was designed to detect a 3 percent difference
in recurrence rates between the groups with
a sample of 2200 patients and a power of 80 percent.
15
The members of the data and safety monitoring
board terminated enrollment one month early
because they determined that the study had sufficient
power to detect a difference in the rate of recurrence
within two years. The study included 1983
patients who underwent surgery, and thus it had
more than 88 percent power to distinguish a difference
of 4 percentage points in recurrence rates, allowing
a two-sided type I error rate of 5 percent and
six interim analyses of the primary end point.
In the primary analysis, the two-year rates of recurrence
were compared between the two groups
according to the intention to treat. The two-year
rates of recurrence were compared with the use of
O’Brien–Fleming boundaries to account for sequential
monitoring of the primary outcome.
25
All 95
percent confidence intervals for the two-year recurrence
rates were adjusted for sequential monitoring,
as were the 95 percent confidence intervals for
the rates or mean values of each secondary outcome.
Subgroup analyses of the primary outcome are
presented as adjusted odds ratios calculated from
logistic-regression analyses after adjustment for
stratification factors (primary or recurrent hernia,
unilateral or bilateral hernia, and study site). Proportions
were compared on the basis of adjusted
odds ratios obtained by logistic-regression analysis
to control for stratification factors. Differences in
outcomes related to pain and functional status were
compared by multiple linear-regression analysis,
with generalized estimating equations used to control
for stratification factors and to account for repeated
assessments. Differences in the times to
return to normal activity, after adjustment for stratification
factors, were assessed by Cox regression
analysis. Statistical tests were not adjusted for comparisons
related to multiple secondary end points
or subgroup analyses. Analyses controlling for
stratification factors were prespecified.
RESULTS
STATISTIC BASELINE CHARACTERISTICS OF THE PATIENTS
Between January 1999 and November 2001, 3518
eligible patients were screened (Fig. 1). Of these
patients, 2164 (61.5 percent) with inguinal hernias
met the entry criteria and were randomly assigned
to either open or laparoscopic hernia repair. The
two-year follow-up period ended in November 2003
and was completed in 85.5 percent (1696) of the
1983 patients who underwent surgery (85.0 percent
of the open group and 87.4 percent of the laparoscopic
group). Ninety-seven of the 989 patients assigned
to laparoscopic repair (9.8 percent) instead
underwent open repair, and 16 of the 994 patients
assigned to open repair (1.6 percent) instead underwent
laparoscopic repair. Intraoperative conversion
to open herniorrhaphy accounted for approximately
half the patients in the laparoscopic group who
did not undergo the assigned repair; the others were
switched to open repair for technical reasons discovered
at the time of surgery or the patient’s preference.
Table 1 shows the baseline characteristics of the
patients according to treatment group. Demographic
characteristics, the characteristics of the hernia,
coexisting conditions, and ASA classifications were
similar in the two groups.
RECURRENCE
The intention-to-treat analysis showed that at two
years, recurrences were more common in the laparoscopic
group (in which there were 87 recurrences
among 862 patients [10.1 percent]) than in the open
group (in which there were 41 recurrences among
834 patients [4.9 percent]; odds ratio, 2.2; 95 percent
confidence interval, 1.5 to 3.2) (Table 2). The
difference remained significant in logistic-regression
analysis that controlled for stratification factors
(primary or recurrent hernia, unilateral or bilateral
hernia, and study site). Rates of recurrence were statistically
similar when analyzed in cohorts enrolled
in the first, second, or third year of the study.
Similar results were obtained in an analysis in
which patients were classified as treated, with the
113 patients who crossed over from their assigned
procedure classified according to the procedure actually
performed. In patients with bilateral hernias
who had a recurrence on the nonstudy side (five patients
in the open group and eight in the laparoscopic
group), inclusion of these recurrences did
not materially affect the results (data not shown).
In additional prespecified analyses, we found a
significant interaction between treatment group and
the type of hernia (primary or recurrent) (P=0.012)
but not between treatment group and whether the
hernia was unilateral or bilateral (P=0.29). With respect
to the repair of primary hernias, the recurrence
rate was significantly higher among patients who
underwent the laparoscopic procedure (79 recurrences
among 781 patients [10.1 percent]) than
among those who underwent the open procedure
(30 recurrences among 756 patients [4.0 percent];
adjusted odds ratio, 2.9; 95 percent confidence interval,
1.8 to 4.5). The same was not true with respect
to the repair of recurrent hernias; the number
of recurrences was similar: 8 of 81 patients in the
laparoscopic group had a recurrence (10.0 percent),
as compared with 11 of 78 such patients in the
open group (14.1 percent; adjusted odds ratio, 0.7;
95 percent confidence interval, 0.3 to 2.0).
COMPLICATIONS AND DEATH
Overall, 718 of the 1983 patients who underwent a
repair procedure (36.2 percent) had at least one
complication; there were 386 complications among
the 989 patients in the laparoscopic group (39.0 percent)
and 332 among the 994 patients in the open
group (33.4 percent) (adjusted odds ratio, 1.3; 95
percent confidence interval, 1.1 to 1.6) (Table 2).
Intraoperative, immediate postoperative, and lifethreatening
complications occurred significantly
more frequently in the laparoscopic group than in
the open group. The rate of long-term complications
(those assessed at three months and at yearly
visits) were similar in the two groups (Table 2).
Within 30 days after the operation there were
two deaths in the laparoscopic group (both considered
to be related to the surgery) and none in the
open group. The two-year mortality rates were not
different between the groups: over the two-year follow-
up period there were 32 deaths in the laparoscopic
group (3.2 percent) and 34 deaths in the
open group (3.4 percent) (adjusted odds ratio, 1.0;
95 percent confidence interval, 0.6 to 1.6). Four
deaths were determined by the end-points committee
to be related to the operation. The causes of
death in these patients were a pulmonary embolus
on postoperative day 3 (in the laparoscopic group);
an intestinal injury during laparoscopic repair (in
the laparoscopic group); a perioperative myocardial
infarction, which led to coronary-artery bypass
surgery and death 60 days after the repair (in the
laparoscopic group); and, 2 years after the repair,
complications from a bowel obstruction in a femoral
hernia (which presumably was missed at the
time of the study operation) (in the open group).
PATIENT-CENTERED OUTCOMES
Patients in the open-repair group had significantly
greater levels of pain (at rest, at work or during exercise,
and during normal activities) than did those
in the laparoscopic group during the two-week
postoperative assessment period. On the day of surgery,
the difference in the mean score on the visualanalogue
scale was greatest (10.2 mm [95 percent
confidence interval, 4.8 to 15.6]), but the score decreased
to 6.1 mm (95 percent confidence interval,
1.7 to 10.5) by the time of the two-week assessment.
The two treatment groups were similar with
respect to all pain assessments by the time the
three-month visit took place (Fig. 2).
The time to the resumption of daily activities
was significantly shorter among those undergoing
laparoscopic repair (median time, four days) than
among those undergoing open repair (five days)
(adjusted hazard ratio for a shorter time to return
to normal activities, 1.2; 95 percent confidence interval,
1.1 to 1.3). Approximately half the patients
(859) were sexually active before the operation; the
time to the resumption of sexual activity was similar
in the two groups (median time, 14 days in the
laparoscopic group and 14 days in the open group).
More patients in the laparoscopic group than in the
open group were able to perform specific activities
(e.g., climbing stairs and engaging in vigorous activities,
such as shoveling or weight lifting) at two
weeks. At three months of follow-up, however, differences
in activity level between the groups were
not apparent.
Both groups had improved function at three
months relative to preoperative levels of function,
according to physical-component scores and mental-
component scores on the SF-36. There were no
differences between the groups in the improvement
in these scores at two years (data not shown).
SURGEONS'S EXPERIENCE
We also performed a post hoc evaluation of the
association between surgeons’ self-reported experience
(the number of procedures previously performed
that involved use of the same technique
[open or laparoscopic] as that for the planned operation,
categorized as 0 to 25, 26 to 50, 51 to 75,
76 to 150, 151 to 250, and more than 250) and rates
of hernia recurrence. The recurrence rate associated
with laparoscopic repair was greater than 10 percent
for the 58 surgeons who reported having performed
250 or fewer laparoscopic repairs in any
category, whereas the recurrence rate was less than
5 percent for the 20 surgeons who reported having
performed more than 250 laparoscopic repairs
(P<0.001 for the comparison of this category to all
other categories). For open repairs, there was no
significant difference in the rate of recurrence between
the most experienced group of surgeons
(those who had performed more than 250 repairs)
and surgeons with less experience (P=0.12). On the
basis of the finding in the laparoscopic group, we
defined “highly experienced” surgeons as those who
reported having performed more than 250 repairs
that involved use of the same technique as that for
the planned operation. During the study period, 15
of 117 surgeons in the open group (12.8 percent)
and 5 of 69 in the laparoscopic group (7.2 percent)
gained enough experience to move into that category.
The interaction between surgeons’ experience
and the treatment group was significant (P=0.013).
Among primary-hernia repairs performed by
highly experienced surgeons, recurrence rates did
not vary significantly according to the type of procedure:
of 253 such procedures in the laparoscopic
group, recurrences occurred after 13 (5.1 percent),
and of 635 such procedures in the open group, recurrences
occurred after 26 (4.1 percent; adjusted
odds ratio, 1.3; 95 percent confidence interval, 0.6
to 2.7). For less experienced surgeons performing
primary repairs, the recurrence rate was greater after
laparoscopic procedures (65 recurrences after 528
such repairs [12.3 percent]) than after open procedures
(3 recurrences after 121 such repairs [2.5
percent]; adjusted odds ratio, 7.4; 95 percent confidence
interval, 2.1 to 26.6). Among repairs of recurrent
hernias performed by highly experienced
surgeons, fewer recurrences were recorded after
laparoscopic repair (1 recurrence after 28 such repairs
[3.6 percent]) than after open repair (11 recur-
rences after 64 such repairs [17.2 percent]; adjusted
odds ratio, 0.3; 95 percent confidence interval,
0.1 to 1.0), but the numbers were small. The number
of recurrent hernia repairs performed by less
experienced surgeons was insufficient to analyze
(with a power below 25 percent to detect a difference
of 15 percent).
DISCUSSION
This multicenter, randomized trial compared two
tension-free, mesh-based hernia-repair techniques:
the Lichtenstein open procedure and the laparoscopic
procedure. Overall, recurrence rates were
higher among patients whose hernias were repaired
by the laparoscopic technique. There was significant
interaction between the surgical approach and
the type of hernia (primary or recurrent). Recurrence
rates were significantly higher after laparoscopic
repair of primary hernias than after open repair of
primary hernias, but recurrence rates associated
with the two techniques were similar for the repair
of recurrent hernias. The presence of bilateral hernias
did not alter the rate of recurrence after either
procedure.
Intraoperative, immediate postoperative, and
life-threatening complications were more frequent
in the laparoscopic-repair group than in the openrepair
group, although rates of long-term complications
and mortality rates were similar in the two
groups. These results are consistent with others’
findings.
11,12
As other studies have reported, patients who
underwent a laparoscopic repair returned to their
usual activities one day sooner than those who underwent
an open repair.
11,12
Differences in activity
levels were not apparent three months after the procedure
and thereafter. Patients who underwent an
open repair experienced significantly higher levels
of pain than those who underwent a laparoscopic
repair, both on the day of operation and at two
weeks, but no significant differences were apparent
after two weeks. Though statistically significant,
the magnitude of the differences in pain may not
be clinically meaningful.
26,27
Results of sequential
SF-36 assessments showed no significant differences
between the two groups at any time. Because
of the large number of secondary end points considered
over several periods, some statistically significant
findings could have occurred by chance alone.
In contrast to other findings published before
this study was initiated, indicating that surgeons’
learning curve for laparoscopic hernia repair plateaued
after as few as 30 cases.
16,17
Post hoc analyses in our study showed a decrease in the rate of
recurrence only among surgeons who reported having
previously performed more than 250 procedures.
Recurrence rates among surgeons who had
performed 250 or fewer laparoscopic hernia repairs
were consistently above 10 percent. Among primary
repairs performed by highly experienced surgeons
(those who had performed more than 250 procedures),
recurrence rates appeared to be similar for
hernias repaired by the laparoscopic approach and
those repaired by the open approach. These findings
should be interpreted cautiously.
The rates of recurrence after repair of a recurrent
hernia did not differ significantly between the
groups. The high rate of recurrences after the repair
of recurrent hernias by the open technique may be
due to the presence of scarring, making further surgery
difficult.
The overall increased rate of recurrence after
laparoscopic repair in our study could be due to
several factors. The high rate of retention in the
study allowed us to assess recurrences thoroughly
during the two-year follow-up period. In addition,
objective assessment of recurrence was performed
by an independent surgeon. The results of our large,
multicenter, randomized trial may be a good indicator
of the results that can be expected in the general
population when hernia repair is performed by
surgeons who are practicing outside of specialized
centers.
This study has several limitations. The average
age of the men enrolled was high, and their healthrelated
quality of life was below that of the general
population.
15
Information on surgeons’ experience
was self-reported and may not have been precise.
We excluded patients who had previously undergone
a hernia repair with the use of mesh, and thus
the data cannot be generalized to second repair procedures
in these difficult cases. We conclude that for
primary hernias, the open technique of tension-free
repair is superior to the laparoscopic technique, both
in terms of recurrence rates and in terms of safety.
Supported by the Cooperative Studies Program of the Department
of Veterans Affairs Office of Research and Development.
Dr. Fitzgibbons reports holding patents for an articulating stapler
and a trocar site-closing device. He also reports serving as an expert
consultant in matters involving a laparoscopic clip applier and
hernia-repair mesh.
We are indebted to the American College of Surgeons for its support
and to Margaret Ring Gillock for her editorial contributions.
This study would not have been possible without the vision of James
Carrico, M.D., who died before its completion.
Appendix
Members of VA Cooperative Study 456 were as follows (asterisks denote former participants): Chair — L. Neumayer (VA Medical Center,
Salt Lake City); Biostatistician — A. Giobbie-Hurder; Health Scientist — J.O. Gibbs; Lead Health Economist — D.M. Hynes; Health Economist
— K. Stroupe; Patient-Centered Outcomes Consultant — M. McCarthy; National Study Coordinator — R. Denwood*; Clinical Nurse
Coordinator — S. Hatton-Ward; Data and Safety Monitoring Board — R. Bell (Northwestern University Medical School, Chicago), H. Buchwald
(Chair) (University of Minnesota School of Medicine, Minneapolis), K.S. Ephgrave (VA Medical Center, Iowa City, Iowa), and R. Woolson
(Medical University of South Carolina, Charleston); Executive Committee — C.J. Carrico (deceased) (University of Texas Southwestern
Medical Center, Dallas), D. Dunlop and J.O. Gibbs (Northwestern University, Chicago), R.J. Fitzgibbons, Jr. (Creighton University, Omaha,
Nebr.), W.G. Henderson (University of Colorado Health Outcomes Program, Aurora), A. Giobbie-Hurder, D.M. Hynes, and D. Reda (Acting
Director) (Cooperative Studies Program Coordinating Center, Hines, Ill.), K. Itani (VA Medical Center, Houston), O. Jonasson (University of
Illinois College of Medicine, Chicago), L. Kim (VA Medical Center, Dallas), M.J. London (VA Medical Center, San Francisco), L. Neumayer
(Chair) (VA Medical Center, Salt Lake City), and T.N. Pappas (VA Medical Center, Durham, N.C.); End Points Committee — M.E. Arregui
(Surgery, St. Vincent’s Hospital and Healthcare Service, Indianapolis), M.J. Bishop (Anesthesiology, VA Medical Center, Seattle), and E. Jensen
(Pathology, VA Medical Center, Salt Lake City); VA Central Office (Washington, D.C.) — J. Feussner (Chief Research and Development Officer),
S. Berkowitz (Assistant Director, Cooperative Studies Program), and J. Gough (Program Assistant, Cooperative Studies Program);
Site personnel — B. Bass, G. Bochicchio, C. Alvarez,* and K.B. Stem (Baltimore); J.J. Gleysteen, K. Mitchell, and R. Ragoza* (Birmingham,
Ala.); G. Rodkey, R. Dennis, D. Soybel,* J. Gordon,* M. Campasano, B. Dionian,* and J. Moriuchi* (Boston); B. Miedema and K. Crews (Columbia,
Mo.); T. Anthony, C. Willis, and C. Rowder* (Dallas); S. Tennenberg, R. Kozol,* and C. Yales (Detroit); N. Lee (Durham, N.C.); S.
Brown (Houston); R. Muldoon,* D. Johnson,* and K. Marchant (Little Rock, Ark.); E. Mangiante, K. Phillips, K. VanFrank, F. Hatmaker,* and
A. Collins* (Memphis, Tenn.); D.M. Hinson and B. Salabsky (Salt Lake City); Q.Y. Duh and M. Marovich (San Francisco); C. Mendez, T. Durant,
and B. Wright* (Tampa, Fla.); G. Glantz, E.H. Livingston,* and W. Murphy (West Los Angeles, Calif.); S. Hatton-Ward and B. Redfield
(Chair’s Office, Salt Lake City); K. Tir, S. Heard, J. Motyka, and C. Sullivan* (Cooperative Studies Program Coordinating Center, Hines, Ill.).
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