Determining the clinical significance of the Chest Wall Injury Society taxonomy for multiple rib fractures

Abstract

BACKGROUND The Chest Wall Injury Society (CWIS) proposals for standardized nomenclature for multiple rib fracture (MRF) classifications were derived by international expert Delphi consensus. This study aimed to validate the CWIS taxonomy using a single-instituion clinical database. METHODS Computed tomography (CT) scans, of 539 consecutive patients with MRFs admitted to a regional major trauma center over a 33-month period, were reviewed (blinded for clinical outcomes). Every rib fracture in every patient was assessed according to each of the CWIS criteria (the degree of displacement, characterization of the fracture line, location of each fracture, and the relationship to neighboring fractures). The clinical significance of the proposed CWIS definitions were determined from independently coded, routinely collected Hospital Episodes Statistics data. RESULTS The radiologic aspects of 3,944 individual rib fractures were assessed. Indicators of injury severity (severe displacement greater series length, and flail segment) were positively associated with other fractures (p < 0.001), hemopneumothorax (p < 0.001), pulmonary complications (p = 0.002), adverse outcomes (p = 0.006), mechanical ventilation (p < 0.001) and prolonged hospital and intensive therapy unit length of stay (p = 0.006, p = 0.007 respectively). Four of the CWIS-proposed definitions were correlated with pulmonary complications and adverse outcomes: the categories of displacement, the definition of individual fracture characterization, the presence of a flail segment. Two definitions for which there was CWIS consensus were not correlated with clinical outcomes: the definition of a series to describe associated fractures on neighboring ribs, the inclusion of a paravertebral sector for fracture localization. CONCLUSION The CWIS rib fracture taxonomy demonstrates clinical relevance. There were associations between the severity of category groups within three of the proposed definitions, based on the clinical outcomes observed. Clinical outcome assessment proved inconclusive for four agreed definitions. Comprehensive, multiinstitutional data collection would be required to provide validation for all the CWIS-proposed definitions. LEVELS OF EVIDENCE Level IV.

Interobserver agreement for the Chest Wall Injury Society taxonomy of rib fractures using computed tomography images

“…However, when the categories for fracture type and displacement were dichotomized, in “simple vs. not simple” and “displaced vs. not displaced,” the agreement improved somewhat, although this was only statistically significant in the AC1 for fracture displacement. Moreover, the clinical significance of categorizing in three rib fracture types is not clear, since only complex fractures are associated with worse outcomes 18 . Potentially, it is sufficient to categorize rib fracture type in only in “simple” and “complex,” not discerning wedge type fractures as a separate category from the simple type since agreement and clinical relevance in this category is low.…”

A new quantitative assessment method for predicting pneumonia caused by chest wall injury

“…For a more accurate prediction, studies have focused on the deformation of the chest wall. 19,21 Given that high thoracic volume after SSRF improves respiratory function, 22 quantitative assessment of thoracic deformation is important.…”

“…In this study, we used data of the Δthoracic volume and focused on chest wall deformation, as in previous studies. 19,21,22 This method has the advantage of using only WBCT imaging data of trauma, making data collection easier and more objective. In addition, the CT imaging data are available immediately after the patient's arrival, allowing an earlier assessment of the onset of pneumonia.…”

“…18 Therefore, a more detailed method to assess the severity of the disease is being explored. [19][20][21] Quantitative analysis of three-dimensional (3D) computed tomography (CT) images has been applied for the evaluation of respiratory function. [21][22][23][24][25][26][27] However, variability in scan conditions in urgent CT prevents the comparison of images among different cases.…”

Does chest wall Organ Injury Scale (OIS) or Abbreviated Injury Scale (AIS) predict outcomes? An analysis of 16,000 consecutive rib fractures

“…This technique was used with other chest wall injury scores which had much better predictive accuracy. 20,25 Perhaps utilizing the advances of modern injury taxonomy and the discrimination seen in other scoring systems could guide updates to the OIS and AIS to improve these scales for the treatment and study of chest wall injuries.…”