Hiatal Hernias Revisited-A Systematic Review of Definitions, Classifications, and Applications

Abstract

Introduction: A hiatal hernia (HH) can be defined as a condition in which elements from the abdominal cavity herniate through the oesophageal hiatus in the mediastinum and, in the majority of cases, parts of the proximal stomach. Today, the role of HHs within the complex entity of gastroesophageal reflux disease (GERD) is very important with regard to its pathophysiology, severity, and therapeutic and prognostic options. Despite this, the application and stringent use of the worldwide accepted classification (Skinner and Belsey: Types I-IV) are lacking. The aim of this study was to carry out a systematic review of the clinical applications of HH classifications and scientific documentation over time, considering their value in diagnosis and treatment.

Methods: Following the PRISMA concept, all abstracts published on pubmed.gov until 12/2023 (hiatal hernia) were reviewed, and those with a focus and clear description of the application of the current HH classification in the full-text version were analysed to determine the level of classification and its use within the therapeutic context.

Results: In total, 9342 abstracts were screened. In 9199 of the abstracts, the reports had a different focus than HH, or the HH classification was not used or was incompletely applied. After further investigation, 60 papers were used for a detailed analysis, which included more than 12,000 patient datapoints. Among the 8904 patients, 83% had a Type I HH; 4% had Type II; 11% had Type III; and 1% had Type IV. Further subgroup analyses were performed. Overall, the precise application of the HH classification has been insufficient, considering that only 1% of all papers and only 54% of those with a special focus on HH have documented its use.

Conclusions: The application and documentation of a precise HH classification in clinical practice and scientific reports are decreasing, which should be rectified for the purpose of scientific comparability.

Keywords: GERD; fundoplication; hiatal hernia; para-oesophageal hernia; upside-down stomach.

Figure 1

Established typing of hiatal hernias by Skinner and Belsey in 1967, subdivided into four types [23].

Figure 2

PRISMA selection of 60 abstracts and original reports on hiatal hernias published between 1926 and 2023 in pubmed.gov.

Figure 3

Endoscopy-based Hill classification: Grade I: normal situation; the mucosa fold is tight around the scope at the EGJ. Grade II: the mucosa fold is less prominent, showing a small space between the scope and mucosa, indicating a weak EGJ. Grade III: there is substantial space between the weakening mucosa and the scope, showing a small hiatal hernia and a widened hiatus. Grade IV: migration of the EGJ into the mediastinum, with a substantial hiatal hernia through the widened hiatus.