Do pelvic dimensions predict recurrence in inguinal hernia? A matched case–control analysis

BACKGROUND: Pelvic morphology has long been implicated in the pathogenesis of inguinal hernia. However, its potential role in recurrence after surgical repair remains unclear. METHODS: In this retrospective, frequency-matched case‒control study, 203 male participants were included: 62 with recurrent inguinal hernia, 63 with primary hernia, and 78 healthy controls. Matching was performed for age, weight, height and BMI between the hernia subgroups. Pelvic morphometric parameters, including the Radioievitch angle and Ami's line, were measured via standardized anteroposterior pelvic radiographs. Receiver operating characteristic (ROC) curve analyses were conducted to assess the diagnostic performance of each parameter. Logistic regression analysis was used to identify independent predictors of hernia presence. RESULTS: All pelvic morphometric measurements were significantly greater in hernia patients than in controls, with Ami's line demonstrating the highest discriminative performance (AUC = 0.772; sensitivity = 65.6%, specificity = 83.3%, p < 0.001). Multivariate logistic regression identified Ami's line as an independent predictor of hernia presence (OR = 8.13, p < 0.001). However, none of the pelvic parameters significantly differed between primary and recurrent hernia patients (p > 0.1), although the Radioievitch angle showed a nonsignificant upward trend in the recurrent group. Notably, a history of heavy labor was significantly associated with hernia recurrence (p = 0.025). CONCLUSIONS: Pelvic bone morphology, particularly the length of the Ami's line, is strongly associated with the presence of inguinal hernia. However, these anatomical features do not appear to predict recurrence. These findings suggest that while the pelvic configuration may influence hernia susceptibility, occupational strain remains a more relevant factor for recurrence.