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What is the research question and/or hypothesis?
 Is infrainguinal approach in patients with femoral hernias improve the outcome
results?
 Is inguinal approach have a better outcome than infrainguinal approach in the
treatment of primary unilateral femoral hernia?
What is the study type?
 This study is a prospective study to compare whether surgical techniques with an
infraingunal approach are better than the inguinal approach in treatment of
unilateral femoral hernia.
 The authors wants to know if there is a difference between the infrainguinal and
inguinal approaches of the operation time, post operative duration of stay, post
operative complications, urinary retention, superficial wound infection, seromas,
foreign body sensation, chronic pain, and reccurence.
What is the reference population? What are the sampling frame and Sampling method
 The study was conducted at the West China Hospital, Sichuan University, from
May 2016 to December 2017.
 This study was approved by the ethics committees of West China Hospital, Sichuan
University. Informed consents were obtained from all patients who agreed to
participate in the study.
 Patients with bilateral, recurrent, and emergency femoral hernias were excluded in
this study.
 Data regarding age, sex, body mass index (BMI), and associated comorbidities
were obtained from all patients.
 Randomization was performed according to the random number table.
Randomization and patients’ allocation in either group were managed by an
independent observer.
In an experimental study, how were subjects assigned to group? In a longitudinal
study how many reached final follow up?
 In this study, 95 subjects were obtained, 13 subjects did not met into the inclusion
criteria. (Bilateral hernia: 2, Recurrent hernia: 3, Emergency: 5, Decline to
participate: 3)
 42 subjects allocated to the infrainguinal approach group and 40 subjects allocated
to inguinal approach group, there are 2 subjects lost to follow up in infrainguinal
approach group.
What are the study factors and how are they measured?
 Femoral hernias account for 2%-4% of groin hernias but are clinically crucial
because they are associated with a higher rate of emergency surgery and bowel
resection. Gallegos et al. relate that the cumulative probability of strangulation for
inguinal hernias was only 2.8% after 3 mo, then rising to 4.5% after 2 y. However,
for femoral hernias, the cumulative probability of strangulation was 22% at 3 mo
and 45% at 21 mo. Dahlstrand et al. reported that 10% of emergency patients with a
femoral hernia were on the waiting list before surgery and, 30% of them were
reported to be on the list for less than 1 mo. Thus, once the diagnosis of a femoral
hernia is confirmed, elective surgery should be advised.
 The infrainguinal plug technique has always been a favorite for its simplicity,
safety, and remarkable effectiveness. Despite its utility, mesh plug repair has been
reported to be associated with a substantial recurrence rate, a postoperative
sensation of a foreign body in the inguinal region, and seromas.
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The inguinal approach in preperitoneal repair of femoral hernias is increasing. A
report by Zandi et al. indicated satisfactory results using this technique for femoral
hernia repair. However, this operation has its shortcomings because it is technically
difficult and time-consuming and disrupts an otherwise normal floor on the inguinal
canal.
 The infrainguinal approach group used the ULTRAPRO Plug (UPP, Ethicon,
Norderstedt, Germany). The inguinal approach group used the ULTRAPRO Hernia
System (UHS, Ethicon, Norderstedt, Germany). Local anesthesia was used in all
procedures, and all operations were performed by the same team.
What are the outcome factors and how are they measured?
 A total of 80 patients, 73 women (91.3%) and 7 men (8.7%), completed the study
(40 in each group). Their ages ranged from 27 to 84 y with a median of 63 y. There
were no statistically significant differences between the study groups with respect
to age, sex, BMI (kg/m2), and associated comorbidities.
 There was also no statistically significant difference between both study groups
with respect to the patients’ postoperative duration of stay (22.7 h versus 21.1 h,
respectively (P = 0.248). As for the complications, the infrainguinal approach group
encountered one case of seroma, one case of foreign body sensation, and one case
of chronic pain, whereas the inguinal approach group encountered two cases of
urinary retention, two cases of superficial wound infection, three cases of seroma,
three cases of foreign body sensation, and four cases of chronic pain. For each
complication listed above, there was no difference between the two groups.
Meanwhile, the treatments of complications in both groups were the same and
sufficient. Urinary retentions and superficial wound infections were resolved by
urine catheterization and dressing changes and appropriate antibiotic administration
guided by sensitivity studies, respectively. All seromas were treated within 2-4 wk
with conservative treatments such as hot compresses. Foreign body sensation and
chronic pain did not affect the normal activity of patients.
What important potential confounders are considered?
 There is no confounding factor in this study.
Are statistical tests considered?
 All data analyses were performed with the Statistical Package for the Social
Sciences (SPSS) version 18 software. Student’s t-test was used for continuous
variables. The chi-squared and Fisher’s exact tests were used for categorical
variables. All P values were two sided. A P value <0.05 was considered statistically
significant.
Are the results clinically/socially important?
10 What conslusions did the authors reach about the research question? Did they generate
new hypotheses? Do you agree with the conclusions?
 In patients undergoing elective primary femoral hernia repair, the infrainguinal
approach has a similar clinical curative effect to that of the inguinal approach.
However, the former has the advantages of simple operation, short operation time,
and fewer complications.
 The most surprising findings reveal that the infrainguinal approach was more
straight forward, and the overall complication rate was lower. The authors believe
that the infrainguinal approach has the following advantages in femoral hernia
repair:
1) No need of incising the inguinal canal during the operation. The operation
time is so short that incising the skin and subcutaneous tissue can only
reveal thehernial sac below the inguinal ligament.
2) As there is no need to incise the inguinal canal, the scope of the operation
adopting the infrainguinal approach does not involve the iliohypogastric,
ilioinguinal, and genitofemoral nerves, which makes the theoretical
possibility of the occurrence of postoperative chronic pain and local
numbness rare.
3) When the UPP is placed, it is not necessary to separate the preperitoneal
space because its anchor is hard and can extend by itself after placement,
which apparently reduces thedifficulties of theoperationand is easy to
master and learn.