The predictive value of skin lesions for intrathoracic and intraabdominal injuries in patients with blunt thoracic and abdominal trauma

Aim To evaluate the predictive value of thoracic and abdominal cutaneous lesions for intrathoracic and intraabdominal injuries detected by computed tomography (CT) in adult patients with blunt torso trauma. Material and Methods This single-center, retrospective observational study included 1523 adult patients (≥18 years) who presented to the emergency department of Duzce University Hospital between June 1, 2014 and June 1, 2024 with blunt thoracic and/or abdominal trauma, were registered as forensic cases, and underwent both chest CT and contrast-enhanced abdominal CT. Demographics, vital signs, trauma mechanism and regions, presence and anatomical location of thoracic/abdominal skin lesions, and CT findings were retrieved from electronic records. The presence of any pathological finding on chest or abdominal CT was defined as the primary outcome. Each cutaneous region (present/absent) was analyzed as a binary predictor using univariable logistic regression, and discriminative performance was assessed by receiver operating characteristic (ROC) curves and area under the curve (AUC). Results The median age of the cohort was 42 (27–59) years, and 69.7% of patients were male. The most common mechanism of injury was traffic accident (45.9%), followed by simple fall (28.6%) and fall from height (17.7%). At least one thoracic CT abnormality was present in 24.8% of patients, and at least one abdominal CT abnormality in 10.6%. The presence of any thoracic skin lesion was associated with a significantly higher rate of thoracic CT pathology compared with no lesion (52.6% vs. 19.7%), with an odds ratio (OR) of 4.52 (95% CI, 3.38– 6.04) and an AUC of 0.615. Likewise, any abdominal skin lesion was associated with a higher rate of abdominal CT pathology (33.9% vs. 7.6%), with an OR of 6.22 (95% CI, 4.28–9.06) and an AUC of 0.639. In contrast, regional models based on specific thoracic and abdominal vii cutaneous zones yielded only low discriminative performance, with AUC values predominantly ranging between 0.50 and 0.55 Conclusion In adult patients with blunt torso trauma, the presence of thoracic or abdominal cutaneous lesions is strongly associated with intrathoracic and intraabdominal injuries on CT and should not be overlooked as a clinical warning sign. However, the low-to-moderate AUC values indicate that these lesions alone are insufficient as a reliable screening or exclusion tool. Thoracic and abdominal skin findings should therefore be interpreted as supportive risk markers that may strengthen the indication for CT—particularly in high-energy mechanisms and multi-region trauma—within an integrated assessment that also considers clinical, physiological and laboratory parameters. Key Words Blunt trauma; Cutaneous lesions; Chest CT; Abdominal CT; Intrathoracic injury; Intraabdominal injury.