Inguinal hernia repairs belong to the most common surgical procedures worldwide. Increasingly they are performed using endoscopical techniques (laparoscopy). Many surgeons prefer to cover the hernia gap with a mesh to prevent recurrence. For it, the mesh must be fixed tightly, but tension free. During laparoscopic surgery the mesh is fixed commonly with staples or tissue glue. However, it is not uncommon that staples cause pain at the staple sites while moving. In addition, staples can cause scarring of the abdominal wall leading to chronic pain.

Aim of the study is to provide evidence that mesh fixation with tissue glue causes less postoperative pain compared to fixation with staples.

Patients with unilateral inguinal hernia will be randomized to receive either mesh fixation with tissue glue or staples (ratio 1:1).

Patients with bilateral inguinal hernia will receive mesh fixation with tissue glue on one side and staple fixation on the other side. The side treated with tissue glue will be randomized (ratio 1:1).

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The inguinal hernia is the most common hernia, including 90% of all spontaneous hernias, and the inguinal hernia repair is the most frequently performed procedure in general surgery. In the United States more than 700,000 inguinal hernias are repaired annually and in Germany more than 200,000. The standard method for inguinal hernia repair, originally described by Bassini in 1889, is the closure of the inguinal canal using sutures. Due to the high recurrence rate of this technique, methods using the tension-free implantation of synthetic meshes were established. Furthermore, endoscopic/laparoscopy methods were established, in which the hernia canal is usually approached from the posterior side opposite to the anterior site in the open approach. It is still hotly debated which of these approaches and methods is the best. Among the various posterior techniques using preperitoneal mesh implantation, the transabdominal preperitoneal patch plastic repair (TAPP) and the total extraperitoneal (TEP) repair achieved the highest acceptance. There are many indications for the use of both techniques, but the TAPP is recommended especially for recurrent hernias (after open preperitoneal patch plastic) and difficult hernias (sliding or incarcerated hernias). The advantages of the TAPP are that it is easier to perform, has a better possibility of standardization, and offers the option to perform a diagnostic laparoscopy. Thus, the type of hernia can be assessed immediately on both sides and a bilateral repair can be performed without additional incisions. In general, learning TAPP is easier than TEP. Most randomized studies comparing laparoscopic with open repair found the following results for laparoscopy: reduced postoperative pain, earlier return to work, increased costs, increased operating time, longer learning period, and during the early learning phase an increased recurrence and complication rate. In summary open, mesh-based, tension-free repair remains the standard, but laparoscopic herniorrhaphy, in the hands of adequately trained surgeons, produces excellent results comparable to those of open repair.

Whether patients suffer from postoperative pain depends on many factors like the type of intervention, complications, age, and individual tolerance. In particular the type of mesh fixation employed during hernioplasty has a strong influence on postoperative pain. In a recent review mesh fixation by glue was compared to mesh fixation with staplers during endoscopic inguinal hernia repair (Surg Laparosc Endosc Percutan Tech (2010) 20:205). For the transabdominal preperitoneal patch plastic repair two randomized controlled trials, one non randomized trial and two case series were identified in this review. Although the authors found reduced postoperative pain and faster recovery after glue fixation without any significant difference in the recurrence rate, the authors still concluded: "As the overall quality of published data remains poor, further well-designed studies are needed until fibrin sealing can replace mechanical stapling as a new standard for mesh fixation." Thus well designed randomized studies comparing glue vs. staples fixation during TAPP are still warranted. Most of the previous studies applied only one mesh fixation method for patients with bilateral hernias. Only one study compared glue and stapler fixation in single patients with bilateral hernias. In this study a 2x2 design will be used, to compare the two fixation methods in patients with unilateral hernia as well as to compare the two methods in the same patient with bilateral hernias, eliminating the interindividual bias of the single hernia group. Furthermore this study focuses on the early postoperative pain, with a rather thorough coverage in the first 2 days. In many other studies the first time pain is measured is one month after surgery, which is the last time point in this study.

The main aim of this trial is to investigate the early postoperative pain after laparoscopic hernia repair in TAPP technique using either fibrin glue or staples for mesh fixation.

Inclusion Criteria:

• primary hernia repair (no re-operation for recurrent hernia)
• good compliance can be expected
• informed consent

Exclusion Criteria:

• chronic pain
• acute pain requiring analgesic others than paracetamol or more than a single dose non-steroidal anti-inflammatory drugs treatment within 48 h before surgery
• current treatment with psychopharmaceutical drugs
• mental incapacity
• known incompatibility (allergies) with the Tisseel compounds