MEDICAL TECHNOLOGY

e-ISSN 1643-3750
© Med Sci Monit, 2019; 25: 4469-4473
DOI: 10.12659/MSM.915430

Received: 2019.01.29
Accepted: 2019.02.24 Single-Site Laparoscopic Percutaneous
Published: 2019.06.16
Extraperitoneal Closure of the Internal Ring
Using an Epidural Needle for Children with
Inguinal Hernia
Authors’ BCDEF
Contribution: Jian-qin Zhang* Department of Pediatric Surgery, Fujian Provincial Maternity and Children’s
Study Design  A
BCDEF Qi-liang Zhang* Hospital, Fuzhou, Fujian, P.R. China
Data Collection  B
BCD
Statistical Analysis  C Liu Chen
BCD
Data Interpretation  D Yu Lin
Manuscript Preparation  E
BCD Yun-jin Wang
Literature Search  F
BCD
Funds Collection  G Dian-ming Wu
Chao-ming Zhou
ABCDEF

* Jian-qin Zhang and Qi-liang Zhang contributed equally to this study and share first authorship
Corresponding Author: Chao-ming Zhou, e-mail: sfyzhouchaoming@163.com
Source of support: Departmental sources

Backgroud: This study evaluated the safety and effectiveness of single-site laparoscopic percutaneous extraperitoneal clo-
sure of the internal ring using an epidural needle for children with inguinal hernia.
Material/Methods: We retrospectively analyzed clinical data of 542 children with inguinal hernia who underwent single-site lap-
aroscopic percutaneous extraperitoneal closure of the internal ring using an epidural needle at our hospital
from June 2014 to June 2017.
Results: All patients successfully underwent surgery and none were converted to conventional surgery. Abdominal vas-
cular injury, vasectomy injury, testicular vascular injury, umbilical hernia, iatrogenic cryptorchidism, testicular
atrophy, hydrocele, hernia recurrence, and scrotal edema were not reported during the perioperative period.
A follow-up of these patients was performed for 12–24 months. During the follow-up period, umbilical hernia,
iatrogenic cryptorchidism, testicular atrophy, and hydrocele were not noted, but 3 cases of hernia recurrence
were found.
Conclusions: The single-site laparoscopic percutaneous extraperitoneal closure of the internal ring using an epidural nee-
dle for children with inguinal hernia is safe and effective, and this procedure has the advantages of minimal
trauma, no scarring, and good cosmetic effect.

MeSH Keywords: Hernia, Inguinal • Laparoscopy • Surgical Procedures, Minimally Invasive

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Background Table 1. Comparison of preoperative clinical data in both groups.

Inguinal hernia is a common disease in pediatric surgery, and Item Group A Group B P value
is usually treated with either traditional open surgery or lapa- Number of patients 542 560
roscopic surgery [1]. The traditional high ligation of the hernia
Age (years) 2.0±1.3 2.1±1.6 0.735
sac was the standard method to treat pediatric indirect hernia.
The surgical technique was simple and the effect was accurate, Boys/girls 452/90 458/102 0.951
but the surgical wound was large, the scar was obvious, and Body weight (kg) 12.8± 2.6 13.5±3.2 0.854
there were many complications [2–5]. With the maturity and
Unilateral/Bilateral 352/190 435/115 0.943
progress of surgical techniques and the development of surgi-
cal instruments, as well as the needs of patients for aesthetic
incision and early postoperative recovery, minimally invasive Patients met the inclusion criteria if they presented with an iso-
surgery has become increasingly popular in various fields [3–8]. lated inguinal hernia. Patients were excluded from this study if
In recent years, single-site laparoscopic percutaneous extra- they: 1) had other congenital deformities, such as cryptorchi-
peritoneal closure of the internal ring using an epidural nee- dism or hydrocele; 2) had an incarcerated hernia; 3) had a re-
dle has been widely and successfully applied in China and else- current inguinal hernia; or 4) refused to sign the consent form
where, and good therapeutic effect has been obtained [9–13]. for surgery or refused to comply with the follow-up schedule.
However, the literature contains few large clinical controlled
studies. The present study retrospectively analyzed the clinical Single-site laparoscopic percutaneous extraperitoneal
data of 1102 patients with inguinal hernia treated in our hos- closure of the internal ring using an epidural needle
pital from June 2014 to June 2017, in order to summarize the
clinical experience and evaluate the safety and effectiveness After anaesthetization, the patient was placed in a supine
of high ligation of single-site laparoscopic percutaneous extra- position with the waist slightly raised using a cushion, and
peritoneal closure of the internal ring using an epidural needle. then we routinely disinfected and draped the surgical area.
The umbilical skin was incised approximately 0.5 cm layer by
layer, and a 5-mm trocar was placed directly into the abdomen
Material and Methods to establish a pneumoperitoneum (12 mmHg). Then, we ex-
plored whether the bilateral inguinal canal was closed. Under
This study was approved by the Ethics Committee of our uni- the guidance of a laparoscope, the skin was punctured at the
versity and strictly adhered to the tenets of the Declaration of unclosed side of the skin by the needle of a No. 12 syringe,
Helsinki. All patients’ guardians signed an informed consent and the epidural puncture needle with double-stranded 2-0
form before the operation. thread was punctured into the anterior wall of the inguinal tube
through the anchor point. We performed a sharp separation of
Patients the outer half-circle of the inner ring mouth at the extraperi-
toneal space and pulled the puncture needle out after the coil
We retrospectively analyzed the clinical data of 1102 chil- was pressed by the laparoscope. The epidural puncture nee-
dren with inguinal hernia. According to the operation mode, dle was pierced into the front wall of the inguinal tube again
the patients were divided into 2 groups: a single-site lapa- through an anchor point with a double-stranded 2-0 thread.
roscopic group (group A, n=542) and a conventional opera- After sharply separating the inner half-circle of the inner ring
tion group (group B, n=560). All preoperative clinical data are mouth at the extraperitoneal space, the epidural puncture nee-
shown in Table 1. There were no statistically significant dif- dle was pierced through the center of the original coil. We also
ferences in gender, unilateral or bilateral, age (median and used the laparoscope to press the coil and remove the punc-
range, group A: 1.8 years, 11 months to 8.5 years, group B: ture needle before tightening the front coil. The pierced coil
1.7 years, 10 months to 9.0 years), and body weight (group A: was removed to bring out the second one. One of the double
12.0 kg, 8.0 to 19.6 kg, group B: 13.2 kg, 7.8 to 21.2 kg) dis- strands was drawn out, and then we gradually tightened the
tribution among these 3 groups, indicating that the 2 groups coil with the inner ring until it closed under the laparoscope.
were homogeneous and comparable. According to the clini- Finally, we tied a knot under the skin. If neither side of the in-
cal manifestation and physical examination, all patients were ner ring was closed, the other side was treated the same way.
positively diagnosed with an inguinal hernia. A routine clinical After closing the inner ring, we carefully checked the abdominal
examination was performed before the operation, including cavity for bleeding, released the peritoneal gas, and removed
an electrocardiogram, chest radiography, and blood examina- the trocar before suturing the umbilical incision.
tion. All patients were followed up for 12 to 24 months, with
a median follow-up time of 15 months.

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MEDICAL TECHNOLOGY

If the abdominal cavity was very deep or there were many peri- Table 2. C
 omparison of perioperative clinical data in both
toneal folds at the inner orifice and it was difficult to puncture groups.
over the deferent duct, we injected normal saline through the
puncture needle to increase the gap between the peritoneum Item Group A Group B P value
and the deferent duct. Alternatively, a 3-mm incision can be
Operative time (min)
made next to the umbilical cord to place grasping forceps for
assistance. Eighteen cases were assisted by hydrodissection Unilateral 20.4±5.2 19.3±4.7 0.874
and 39 cases were assisted by grasping forceps. Bilateral 31.2±4.8 29.1±5.2 0.851
Amount of bleeding
Conventional operation 1.5±0.3 2.1±0.6 0.614
(ml)
Postoperative
After anaesthetization, the patient was placed in supine po- 1.1±0.3 1.3±0.3 0.961
hospital stay (d)
sition with the waist slightly raised using a cushion. A 1.5- to
Hospital costs
2-cm incision parallel to the inguinal ligament was made at (1000 RMB)
8.1±1.8 5.0±1.6 0.048
the midpoint of the inguinal ligament. The skin and subcuta-
The incision length
neous tissue were cut layer by layer, and the aponeurosis of 0.6±0.2 2.3±0.8 0.030
(cm)
the ventral oblique muscle was opened and dissociated and
then separated to the outer ring. After opening the outer ring Transfer to
0
conventional surgery
and finding the hernia sac, we cut the anterior wall of the her-
nia sac. If there were no contents, we transected the posterior
wall, and then striped the tissue around the proximal hernia Table 3. P
 ostoperative complications comparison between 2
sac to the extraperitoneal fat. We ligated the hernia sac twice groups.
and sutured it once with No. 1 thread to perform high liga-
tion of the hernia sac. After hemostasis, the surgical incision Item Group A Group B P value
was sutured layer by layer.
Abdominal vascular injury 0 0

Statistical analysis Vasectomy injury 0 0

Testicular vascular injury 0 0

Continuous data are presented as mean ± standard deviation
and range. Clinical parameters between the 2 groups were Testicular atrophy 0 0
compared with the independent-samples t test and the c2 or Umbilical hernia 0 0
Fisher’s test for categorical variables. A p value of <0.05 was
Iatrogenic cryptorchidism 0 0
defined as statistical significance.
Scrotal edema 0 0

Hydrocele 0 18 0.000
Result
Hernia recurrence 0 0
All patients successfully underwent surgery and none were
Poor wound healing 2 5 0.274
converted to conventional surgery. The operation time was
14 to 45 min (unilateral 20.4±5.2 min, bilateral 31.2±4.8 min). Pain and discomfort in
2 13 0.005
groin area
The amount of bleeding was 1 to 3 ml (1.2±0.2 ml). The du-
ration of hospital stay was from 1 to 2 days (1.1±0.3 days).
iatrogenic cryptorchidism, testicular atrophy, hydrocele were
Of the patients who underwent single-site laparoscopic sur- noted, but 3 cases of hernia recurrence appeared.
gery, some experienced minor complications, including poor
wound healing and pain or discomfort in the groin area. These Table 2 shows the high successful closure rate in both groups,
complications were treated via medication or resolved spon- with no significant difference among the clinical parameters
taneously. No abdominal vascular injury, vasectomy injury, between the 2 groups (P>0.05), indicating that the surgical out-
testicular vascular injury, umbilical hernia, iatrogenic crypt- comes of the 2 surgical procedures were similar. Although the
orchidism, testicular atrophy, hydrocele, hernia recurrence, or cost of hospitalization in the laparoscopic group was higher
scrotal edema were reported during the perioperative period. than with the traditional operation group, the incision length
The overall follow-up period ranged between 1 and 2 years, was significantly shorter (P<0.05). As shown in Table 3, there
and during the follow-up period, no cases of umbilical hernia, were no cases of abdominal vascular injury, vasectomy injury,

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Table 4. F ollow-up period comparison between 2 group of surgery group, the incidence of edema of scrotum and poor
patients. wound healing was significantly higher in the traditional sur-
gery group than in the single-hole laparoscopic group (P<0.05).
Item Group A Group B P value
Bilateral hernia and occult hernia in children are were very com-
The length of scar (cm) 0.1±0.1 2.4±0.7 0.022
mon, and the incidence of occult hernia was 21% according to
Occult hernia on Zhou [20]. Steinau reported that 5% to 10% of children with
0 10 0.002
contralateral side unilateral hernia have a contralateral oblique hernia after sur-
Hernia recurrence 3 5 0.507 gery [21], and Shalaby and Bertozzi both reported that about
10% to 20% of patients diagnosed with unilateral inguinal her-
Umbilical hernia 0 0 nia before surgery were found to have a contralateral occult
Testicular atrophy 0 0
hernia during the laparoscopic operation [22,23]. In the pres-
ent study, 46 patients in the laparoscopic group who were di-
Iatrogenic cryptorchidism 0 0 agnosed with a unilateral inguinal hernia before surgery were
found during the exploration to have a contralateral inner ring
Scrotal edema 0 0
that was not closed, and 10 patients in the conventional group
were found to have an occult hernia on the contralateral side
testicular vascular injury, umbilical hernia, iatrogenic cryptorchi- during the follow-up period, which required a second operation.
dism, testicular atrophy, hydrocele, hernia recurrence, or scrotal Laparoscopic surgery can simultaneously explore the situation
edema after surgery in either group. In the conventional oper- of the bilateral inner ring, so the children with contralateral oc-
ation group, there were more scrotal edema and groin traction cult hernia could be treated simultaneously without the need
pain, and the difference was statistically significant (P<0.05). of additional surgical instruments and costs. The injury to chil-
Table 4 shows that there were no significant differences during dren was also very small and had no effect on postoperative
the follow-up time evaluations between the 2 groups (P>0.05), recovery, which avoided the injury and cost of a second oper-
indicating that significant between-group differences did not ation. Hernia recurrence is a complication of conventional sur-
exist with regard to early and mid-term efficacy. The incidence gery and laparoscopic surgery, and it is reported that the recur-
of surgical scarring and contralateral occult hernia was signif- rence rate of hernia in conventional surgery and laparoscopic
icantly higher in the conventional surgery than in the laparo- surgery is 0% to 6% [24]. High ligation of the hernia sac is an
scopic surgery (P<0.05). effective method for treating pediatric inguinal hernia, and the
therapeutic effect was closely related to the high degree of li-
gation. Laparoscopic high ligation of hernia sac was performed
Discussion at the orifice of the inner ring, which realized the true sense of
high ligation. The causes of recurrent hernia after laparoscopic
Inguinal hernia is one of the most common congenital diseases surgery include incomplete peritoneal ligation and accidental
of children, occurring in 1% to 2% of mature infants and in up slippage of the ligation knot [25]. Therefore, the position of the
to 30% of preterm infants [14,15]. Surgical methods include ligation must be high enough, the ligation line must be complete
traditional open surgery and laparoscopic surgery. The tradi- for a circle, and the suture should be tightened securely so as
tional operation requires dissecting the inguinal canal, which to avoid recurrence of the hernia due to the remaining space.
has many problems, such as injury to the spermatic vessels,
deferent duct, nerves, and levator muscles, and the incidence Single-site laparoscopic percutaneous extraperitoneal closure
of complications such as scrotal edema and poor wound heal- of the internal ring using an epidural needle only requires plac-
ing is high after the operation due to the free spermatic cord ing the laparoscope into the abdominal cavity and use simple
and hernial sac [2–5]. Perlstein reported that 2.3% to 15% of puncture technology and knot, without special laparoscopic
patients have testicular dysplasia, atrophy, or even iatrogenic suture technology, which is very simple and easy to master.
cryptorchidism [16]. However, laparoscopic surgery does not re- Although it is less invasive and easier to perform, the follow-
quire dissecting the inguinal canal and free hernia sac, which ing guidelines should be followed during the operation. First,
helps ensure physiological integrity of the inguinal canal, and before the operation, patients should empty their bladder to
the laparoscopic visual field is clear and magnified, which can avoid affecting the visual field exposure, the space for oper-
clearly expose the inner ring and its surrounding tissue, avoid- ation, and injury to the bladder. Second, make full use of the
ing injury to the spermatic cord and deferent duct during sur- laparoscopic lens to push and press the peritoneum around the
gery [17–19]. In the present study, although there were no inner ring to assist proper placement of the needle, and this is
complications of deferent duct injury, testicular vascular injury, key to a successful operation. Third, the needle must be placed
iatrogenic cryptorchidism, or testicular atrophy in the traditional between the abdominal transverse fascia and the peritoneum.

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Fourth, squeeze out the gas and fluid in the hernia sac when Conclusions
tightening the suture to avoid accumulation of gas and fluid in
the hernia sac after the operation. Fifth, pull the skin slightly The single-site laparoscopic percutaneous extraperitoneal clo-
when tying the knot to avoid ligation of the dermis, leading sure of the internal ring using an epidural needle for pediatric
to a linear response after the operation. These guidelines will inguinal hernia is safe and effective, and this procedure has
help obtain good clinical results. All the patients in the pres- the advantages of minimal trauma and no scarring, and can si-
ent study underwent laparoscopic surgery successfully, and multaneously detect and treat the contralateral occult hernia.
none of them had to be converted to open surgery. No um-
bilical hernia, iatrogenic cryptorchidism, testicular atrophy, or Ethics approval
hydrocele were found after the operation or during the early
follow-up period. The single-site laparoscopic operation had This study was approved by the Ethics Committee of our uni-
the same safety and effectiveness as the conventional opera- versity and strictly adhered to the tenets of the Declaration
tion, and was superior to the conventional surgery in the cos- of Helsinki.
metic effect and the discovery and treatment of contralateral
occult hernias. Although the cost of single-site laparoscopic Acknowledgements
operation is higher, it is still generally affordable to families.
We are very grateful to the participating doctors: Yi-fan Fang,
Although this retrospective study had a large sample size, Bing Zhang, Ming-kun Liu, Jian-cai Chen, Jian-xi Bai, Wen-chen
there are still several limitations. First, this was a single-center Xu, and Yuan-bin He.
study, and more research from multiple centers is needed to
assess the effectiveness and complications of this technique. Conflict of interests
Second, the follow-up period was short, and studies with lon-
ger follow-up are needed. None.

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