Biologic Mesh, Hernia Inguinal
Conditions
Brief summary
Inguinal hernia is one of the most common conditions in general surgery. In clinical practice, surgeons frequently face a dilemma: during the evaluation of a patient with unilateral symptomatic inguinal hernia, a contralateral asymptomatic defect is discovered-either preoperatively on physical examination or intraoperatively during laparoscopy. The question then becomes: how should this incidental finding be managed? Epidemiological data show that the incidence of such contralateral asymptomatic hernias can be as high as 20%. The management strategy for these hernias has changed considerably over time. Although traditional "watchful waiting" was once widely adopted, long-term follow-up studies have demonstrated that approximately 70% of asymptomatic patients eventually require surgery due to symptom progression, and increasing age is associated with higher surgical risks. Consequently, with the widespread adoption of laparoscopic techniques, simultaneous repair of asymptomatic hernias during the initial surgery has become a common clinical choice. However, this decision raises a critical question: how can the surgeon balance the need to repair the existing anatomical defect against the risk of introducing new long-term complications from the intervention? This makes the choice of repair material particularly important. Currently, synthetic polypropylene meshes, with their proven effectiveness in reducing recurrence rates, are considered the gold standard for inguinal hernia repair. However, as permanent implants, they may be associated with long-term complications-chronic postoperative pain and foreign body sensation, which affect patients' long-term quality of life. Biologic meshes offer a different option. Derived from decellularized extracellular matrix, they are designed as temporary scaffolds that guide autologous tissue regeneration and ultimately degrade. Theoretically, this avoids a permanent foreign body reaction and may reduce long-term discomfort. Nevertheless, the clinical value of biologic meshes in inguinal hernia repair remains controversial. Some studies suggest that biologic meshes reduce chronic pain and improve quality of life; others show no difference in pain or recurrence rates compared with synthetic meshes. Meta-analyses have not demonstrated clear superiority of biologic over synthetic meshes in overall complications, recurrence, or chronic pain, and the heterogeneity among existing studies is high. The BIOLAP randomized clinical trial, published in JAMA Surgery in 2025, provided high-level evidence for symptomatic bilateral hernias. It showed that in laparoscopic inguinal hernia repair, biologic mesh did not significantly reduce postoperative pain. Moreover, it was associated with a significantly higher 2-year recurrence rate (11.2% vs. 2.5%) and a higher seroma rate (33.4% vs. 21.6%). However, a key question remains: can these conclusions be directly extrapolated to the setting of contralateral asymptomatic hernia repair, where the therapeutic goal is to maximize long term comfort rather than to relieve existing symptoms? The investigators previously conducted an exploratory single-center randomized controlled study (n=52, BiSOH) that addressed this question preliminarily. In that trial, the biologic mesh group had significantly lower inguinal pain scores at both 1 month and 6 months, with pain decreasing over time in both groups. Quality of life measured by SF-36 was significantly better in the biologic mesh group at both follow-up time points, and the EQ-5D score was higher at 6 months. These findings suggest that biologic mesh may offer advantages in chronic pain control and quality of life for occult hernia repair, contrasting with the BIOLAP conclusions. However, the single center design and methodological limitations prevented confirmation of the primary endpoint difference, highlighting the need for a multicenter, high-quality clinical trial. Currently, international guidelines lack high level evidence on the optimal mesh type for simultaneous repair of contralateral asymptomatic hernias. Therefore, this multicenter, randomized, single-blinded, parallel-controlled trial was designed to compare biologic versus synthetic meshes in this specific scenario. The hypothesis is that the use of a biologic mesh (porcine UBM/SIS composite) reduces chronic pain on the asymptomatic side at 6 months without increasing recurrence, compared with a synthetic mesh (self-gripping polyester). The biologic mesh is a porcine urinary bladder matrix and small intestinal submucosa composite (UBM/SIS) manufactured by ZR Medtech (Suzhou, China). It is a non-cross-linked, acellular, collagenous matrix produced through patented decellularization and antigen removal processes. It has been used for various soft tissue defect repairs.
Interventions
A non-cross-linked, acellular, collagenous matrix derived from porcine urinary bladder matrix and small intestinal submucosa (UBM/SIS). Unlike permanent synthetic meshes, this biological mesh is designed to gradually degrade and be replaced by autologous tissue, potentially reducing chronic pain and foreign body sensation. Used for contralateral asymptomatic hernia repair during laparoscopic TAPP.
A large-pored, lightweight, self-gripping polyester mesh. Used as active comparator for contralateral asymptomatic hernia repair during laparoscopic TAPP.
Sponsors
Study design
Masking description
the trial as long as the symptomatic side has not developed a recurrences.
Intervention model description
This is a multicenter, randomized, single-blinded, parallel-controlled trial. Eligible patients will be randomized in a 1:1 ratio to receive either biologic mesh (UBM/SIS) or synthetic mesh (self-gripping polyester) for the asymptomatic side repair. The symptomatic side will be repaired uniformly with synthetic mesh (self-gripping polyester) in all patients. The surgical procedure is laparoscopic TAPP.
Eligibility
Inclusion criteria
* Age 18 to 80 years * Unilateral symptomatic inguinal hernia with contralateral asymptomatic hernia (diagnosed either preoperatively as a clinically asymptomatic hernia or intraoperatively as an occult hernia) * Planned for laparoscopic transabdominal preperitoneal (TAPP) repair and consent to simultaneous repair of the contralateral asymptomatic hernia * Written informed consent obtained
Exclusion criteria
* Incarcerated or strangulated hernia requiring emergency surgery * Inability to receive porcine-derived devices (religious or ethnic reasons) * Participation in other interventional trials within the last 6 months * Acute systemic infection or skin disease near the surgical site * Chronic pain syndrome or long-term use of analgesic medications * Pregnancy, planned pregnancy, or breastfeeding * Any condition judged by the investigator as unsuitable for trial participation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Chronic pain on the asymptomatic side at 6 months after surgery | 6 months after surgery | Pain will be measured using a numerical rating scale (NRS, 0-10 points) and documented separately for each side. At the 6 month follow up, patients will assess the most severe pain experienced in the past week for the left and right inguinal regions independently. The primary endpoint is the NRS score reported for the asymptomatic side. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain assessment | Postoperative day 1 and 1 month after surgery | NRS scores (0-10) assessed on each side at postoperative day 1 (before discharge) and at the 1-month follow-up visit. |
| Short-Form Inguinal Pain Questionnaire (SF-IPQ) | 1 month and 6 months after surgery | Validated questionnaire assessing pain characteristics, frequency, and impact on daily activities. Scores range from 0 to 12. Higher scores indicate more severe pain or functional limitation. |
| Quality of life (SF-36) | Preoperatively, and at 1 month and 6 months after surgery | Short Form 36 (SF-36) assesses physical and mental health components. Scores range from 0 to 100. Higher scores indicate better quality of life. |
| Recurrence on the asymptomatic side | 6 months after surgery | Clinical recurrence defined as a reducible mass on physical examination, confirmed by ultrasound if uncertain. |
| Postoperative complication rates | Up to 6 months after surgery | Incidence of seroma, hematoma, surgical site infection, and other adverse events |
| Patient satisfaction | 1 month and 6 months after surgery | The Patient Satisfaction Scale assessing patient satisfaction with the surgical outcome. Scores range from 0 to 100. Higher scores indicate greater satisfaction. |
| Operative time | Perioperative | Total operative time from skin incision to closure, measured in minutes. |
| Postoperative hospital stay | up to 6 months | Cumulative length of hospital stay from the date of surgery until the 6-month follow-up, measured in days. This includes the initial postoperative stay and any re-hospitalizations related to the inguinal hernia or its surgical repair (e.g., due to recurrence, infection, seroma, hematoma, or other mesh-related complications). |
Countries
China
Contacts
Xiangya Hospital of Central South University