Comparison of bilateral to unilateral total extra-peritoneal (TEP) inguinal hernia repair: a systematic review and meta-analysis

PURPOSE: Laparoscopic herniorrhaphy (LH) has become the treatment of choice in many centers for patients with inguinal hernia (IH). Our aim was to compare the morbidity outcomes of bilateral vs unilateral IH repair using the laparoscopic total extra-peritoneal (TEP) technique, to determine whether undertaking bilateral IH repair places patients at additional risk. METHODS: Manuscripts published up to the end of 2021 on PubMed/MEDLINE, EMBASE, Cochrane Library, Scopus, and Web of Science were searched. Patients (> 16 years) undergoing a primary elective unilateral or bilateral TEP operation, using the standard 3-port laparoscopic technique, were identified. Quality of evidence was assessed using the GRADE criteria. Meta-analysis was conducted where possible. Where this was not possible, vote counting was conducted using effect direction plots. RESULTS: Eight observational studies, with a total of 18,153 patients were included. Operative time was significantly longer for bilateral operations. There was no significant difference in conversion to open, post-operative seroma, urinary retention, haematoma, and length of hospital stay. There was an increased rate of hernia recurrence in patients undergoing bilateral IH repair. CONCLUSION: Although limited by the observational nature of the included studies, there is no conclusive evidence to suggest a differential burden of morbidity between unilateral and bilateral TEP IH repair. As all included papers are from observational studies only, evidence from all outcomes is at best very low quality. This manuscript thereby highlights a need for randomized controlled trials to be conducted in this area. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10029-023-02785-0.