Laparoscopic transabdominal preperitoneal repair versus open mesh plug repair for bilateral primary inguinal hernia

Abstract Aim A few studies comparing laparoscopic and open techniques have reported that open repair with mesh is the optimal operation for unilateral primary hernia. The aim of this study is to compare the outcomes of laparoscopic transabdominal preperitoneal repair (TAPP) versus open mesh plug repair (MP) for bilateral primary inguinal hernia. Methods This was a retrospective study of 107 patients with bilateral primary inguinal hernia between January 2008 and December 2016. Of these patients, 49 underwent TAPP and 58 underwent MP. The surgical outcomes and the long‐term outcomes using a questionnaire were compared between TAPP and MP. Results In the TAPP group, the operation time was significantly longer (103 vs 91 minutes; P = .019). The postoperative complication rate was not significantly different between the two groups. One patient (1.0%) in the TAPP group and five patients (4.3%) in the MP group suffered recurrence (P = .30). Postoperative groin pain was not significantly different (14% in the TAPP group vs 31% in the MP group; P = .065), but more patients required analgesics in the MP group (4.1% vs 17%; P = .036). The long‐term outcomes, according to a questionnaire, were not significantly different between the two groups. The median follow‐up period was 22 (range, 0.4‐52) months in the TAPP group and 40 (range, 0.5‐108) months in the MP group (P < .001). Conclusion TAPP for bilateral primary inguinal hernia achieved better results than MP relative to postoperative pain and the use of medication for pain relief without increasing the complication and recurrence rates.


| INTRODUC TI ON
Inguinal hernia repair is the most frequently performed operation in general surgery. Inguinal hernia repair has evolved from the old herniorrhaphy techniques to tension-free repair using mesh and, ultimately, laparoscopic approaches. Laparoscopic inguinal hernia repair was first performed by Ger et al in 1988 1 and has been proven as an efficient technique, serving a valuable alternative and offering the advantages of minimally invasive surgery. 2 However, the optimal approach-open/anterior or laparoscopic/endoscopic/posterior repair-is still a topic of discussion.

In 2004, for unilateral primary inguinal hernia, a large Veterans'
Affairs study compared open mesh and laparoscopic techniques and declared that open repair with mesh was the optimal operation. This outcome linked the laparoscopic approach to increased complication and recurrence rates in addition to the need for general anesthesia. 3 Over the last 12 years, multiple studies have compared these two operations and reported that the recurrence rates were similar, but they have shown conflicting results on the perioperative outcomes and costs. 4,5 For bilateral inguinal hernia, two prospective randomized trials 6  According to our policy, a contralateral occult inguinal hernia identified at the time of TAPP repair is not repaired. All patients enrolled in this study were diagnosed with bilateral primary inguinal hernia prior to surgery.

| MATERIAL AND ME THODS
All patients were given a single intravenous dose of antibiotics preoperatively. After surgery, analgesics were given on demand when the standard protocol did not achieve adequate pain control. If there are no signs of major complications, patients can be discharged on postoperative day (POD) 2 according to the perioperative and postoperative management protocols (clinical pathways). All patients were followed up as outpatients within 2-3 weeks postoperatively to assess groin pain, medication requests, and any complications. A further clinical follow-up was conducted by a patient's general practitioner, with referral back to the hospital if any problems developed.
The following variables were recorded from a retrospective review of medical records: clinical characteristics and surgical and postoperative outcomes (including complications). Postoperative complications such as seroma, bleeding, infection, orchitis, chronic pain, and recurrence were evaluated and were graded according to the Clavien-Dindo classification. 11 Intra-and postoperative complications were recorded if a complication presented on at least one side. Seroma was defined as some amount of fluid collection in the inguinal region requiring puncture. Chronic pain was defined as the presence of pain 3 months after surgery that persists beyond 6 months after surgery. 12 In addition, the parameters reflecting postoperative recovery, such as groin pain and analgesic use, were measured in the outpatient setting within 2-3 weeks postoperatively.
In 2017, long-term outcomes were analyzed retrospectively using a questionnaire. The questionnaire included six parts that covered: (a) the degree of satisfaction with the procedure (good, fair, poor); (b) pain (none, sometimes, often); (c) numbness (none, sometimes, often); (d) discomfort (none, sometimes, often); (e) recurrence (yes or no); and (f) the time required to return to normal activity. Patients who provided answers suggesting recurrence or hoping for a medical examination were asked to visit our department for confirmation.

| TAPP repair
The laparoscopic technique was performed using the transabdomi- The skin was closed with a 4-0 Vicryl (polyglactin; Ethicon Inc) interrupted suture.

| MP repair
Open inguinal hernia repair was carried out using the mesh plug technique under local anesthesia with sedation, if required. 10

| Statistical analysis
All statistical analyses were performed with EZR (Saitama Medical Centre, Jichi Medical University; Kanda, 2012), which is a graphical user interface for R (The R Foundation for Statistical Computing, version 2.13.0). 13 To compare treatment groups, categorical variables were analyzed using the Chi-squared test, and the Student's t-test or the Mann-Whitney U test was used to compare continuous variables as appropriate. P values < .05 were considered statistically significant.  Table 1. The median age of the MP group was significantly higher than that of the TAPP group, but there were no differences in gender and BMI between the two groups. The rates of comorbidities, cardiac angina, cerebrovascular disease, and COPD in the MP group were significantly higher than in the TAPP group. No patients had steroid therapy.

| RE SULTS
Surgical outcomes are summarized in Table 2. In the TAPP group, the operation time was significantly longer (103 vs 91 minutes) and the estimated blood loss was significantly less (3.3 vs 9.3 mL). No intraoperative complications were observed in either group. Postoperative outcomes are presented in Table 3. The postoperative complication rate was not significantly different between the two groups. Seroma    Table 4). The open procedures included preperitoneal prosthetic repair through a vertical midline incision in study 1, Shouldice repair in study 2, Lichtenstein repair in studies 3 and 4, and MP in our case.

| D ISCUSS I ON
Overall, the duration of the operation (partial with a large variation) was slightly longer for TAPP than for the open procedure. The fairly long operative procedures were partly due to the lesser experience of the surgeons. TAPP was influenced by the learning curve. TAPP was introduced at our institution in December 2012 and we are inexperienced with regard to this technique. With a learning curve of 250 cases, TAPP could arguably be classified as a complex laparoscopic operation that requires additional training. 23 If we continue to improve our laparoscopic skills, we believe that the operation time for TAPP will decrease. Although there are differences in the definitions of complications, our complication rates, except for recurrence (6.1% in the TAPP group and 2.6% in the MP group), were not higher than that of other studies and there were no differences between the two groups. The long-term complications that we focused on were recurrence, chronic pain, numbness, and discomfort. Finally, we asked the patients to report their satisfaction with the procedure. The retrospective analysis of 216 patients who underwent open or laparoscopic repair using a Short-Form 36 (SF-36) revealed no significant difference scores between the two groups. 31 Additionally, there were no significant differences in recurrence, pain, numbness, and discomfort between the two groups in our study, indicating that satisfaction with the procedure was similar in both groups and was comparable to previously reported results. 32 The present study has several limitations. The main limitation includes the possible presence of biases, including age and comorbidities, because of the retrospective study design. The sample size was not large (49 cases in the TAPP group vs 58 cases in the MP group) and the follow-up periods were not long (median 22 months in the TAPP group and 44 months in the MP group). However, the results are helpful in terms of processing prospective randomized clinical trials comparing TAPP and MP for bilateral inguinal hernia repair.
In conclusion, TAPP for bilateral primary inguinal hernia achieved better results than MP relative to postoperative pain and the use of medication for pain relief without increasing complication and recurrence rates.

D I SCLOS U R E
Conflict of Interest: Authors declare no conflict of interests for this article.

E TH I C A L A PPROVA L
The protocol for this research project has been approved by the