# The distribution of lateral rib fractures: a validation and further development of the AO/OTA classification system in patients with fractures at the rib shaft

**Authors:** Johannes Groh, Florian Kern, Johannes Krause, Mario Perl, Stefan Schulz-Drost

PMC · DOI: 10.1007/s00068-025-02795-w · 2025-02-23

## TL;DR

This study examines the distribution and classification of lateral rib fractures using the AO/OTA system, revealing patterns that could improve clinical understanding and treatment.

## Contribution

The study validates and refines the AO/OTA classification system for rib fractures by identifying specific distribution patterns and advocating for subsegmental divisions.

## Key findings

- Fractures predominantly occurred between the fifth and seventh ribs in the anterolateral to lateral region.
- Type A fractures were more anterior, while type B fractures and dislocations were more posterior.
- Adjacent ribs showed clustering of injuries, with a caudal shift in fracture density observed.

## Abstract

Rib fractures are prevalent and clinically significant injuries, often associated with thoracic trauma. Despite their frequency, the precise distribution and characteristics of rib shaft fractures remain underexplored. This study investigates the distribution, location, and classification of lateral rib fractures using the AO/OTA classification, focusing on fracture patterns and the relationship to neighbored ribs.

The study retrospectively analyzed 116 patients with 617 isolated rib fractures treated at a Level 1 trauma center over seven years. Using CT scans, fractures between the tubercle and osteochondral junction of the rib shaft were examined. Fracture type, dislocation, and location were categorized according to AO standards. The 116 patients underwent detailed statistical analysis to identify distribution patterns and correlations between fracture characteristics.

The fractures predominantly occurred between the fifth and seventh ribs, with a focus in the anterolateral to lateral region (40°–69°). Type A fractures were more anteriorly located, while type B fractures and dislocations shifted posteriorly. A regression analysis confirmed the significance of fracture type and dislocation in determining fracture position. Moreover, fractures showed clustering patterns, with adjacent ribs more likely to be injured. A caudal shift in fracture density and localization from the cranial to the caudal thorax was also observed.

The findings validate the AO/OTA classification for rib fractures, highlighting the need for refined subsegmental divisions within the rib shaft for more precise clinical application. The study underscores the relationship between fracture location, type, and associated injuries, advocating for multicenter studies and a comprehensive classification system for thoracic trauma. This could enhance our understanding of injury patterns and inform treatment strategies.

## Full-text entities

- **Diseases:** trauma (MESH:D014947), Rib fractures (MESH:D012253), Fracture (MESH:D050723), dislocation (MESH:D004204), thoracic trauma (MESH:D013896)
- **Species:** Homo sapiens (human, species) [taxon 9606]

## Figures

12 figures with captions in the complete paper: https://tomesphere.com/paper/PMC11847753/full.md

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Source: https://tomesphere.com/paper/PMC11847753