Research on the current situation of animal models of abdominal wall hernia in the field of animal experiments: a systematic review of 9098 animals with abdominal wall hernia model.

backgroundAnimal models are essential for advancing clinical research on abdominal wall hernias. However, existing preclinical studies often have inconsistencies and limitations, hindering the translation of findings into clinical practice. This systematic review evaluates preclinical animal studies to summarize methodologies used in abdominal wall hernia research, aiming to standardize animal model development and improve the clinical relevance of research outcomes. MATERIALS AND

methodsA systematic search was conducted across databases like PubMed, Embase, Web of Science, CNKI, Wanfang, CQVIP, and CBM, focusing on preclinical animal studies using mesh interventions for abdominal wall hernias. The SYRCLE tool was used to assess the methodological quality and risk of bias in the included studies. Key study characteristics, including animal details (species, sex, weight, etc.) and modeling specifics (hernia type, defect size, repair method, etc.), were extracted and analyzed.

resultsThe review included 246 medium-quality studies involving 9,098 animals from eight species. Rats (54.1%) and rabbits (17.5%) were the most common small animal models, while pigs (21.5%) dominated large animal studies. Female animals prevailed among the small models (48.1%), while males were in the majority among large species (61.9%). Acute hernia models were investigated far more often than chronic ones (76.1% vs. 23.9%). Single defects, typically at the midline or linea alba (74.8%), were more frequently studied than multiple defects (17.9%). Full-thickness defects (57.0%) were more common than partial-thickness (20.7%), with some studies not specifying defect depth (22.3%).

conclusionLarge animal models, like pigs, are anatomically similar to humans and better for evaluating hernia repair outcomes, while small animals, such as rats, are more suitable for biocompatibility studies due to cost and ethical considerations. Chronic hernia models better reflect clinical conditions than acute ones. Midline or linea alba defects are preferred, with single defects being more common. Defect dimensions vary by species, and future research could explore specific anatomical sites. There is no consensus on defect depth, which is often determined by modeling success and research goals.

trial registrationThis study reports the results of the preregistered study with complete analysis plans, which can be accessed on the PROSPERO platform with CRD420251004354. (Protocol registration: PROSPERO CRD420251004354).