STUMBL vs TTSS in Predicting Morbidity and Mortality of Blunt Chest Trauma

STUMBL (Study of the Management of Blunt Chest Wall Trauma) vs TTSS (Thoracic Trauma Severity Score) in Prediction of Morbidity and Mortality Rate of Blunt Chest Trauma

This study aim to compare the effectiveness of the STUMBL Score and the Thoracic Trauma Severity Score (TTSS) in predicting morbidity and mortality in patients with blunt chest wall trauma, and to evaluate which scoring system provides greater clinical utility for early risk stratification and management decisions.

Blunt chest wall trauma poses a clinical challenge due to its substantial contribution to morbidity and mortality, particularly following falls and vehicular accidents. Early identification of patients at high risk of complications is critical yet difficult, as delayed respiratory issues often escape initial detection. Traditional trauma scoring systems (e.g. ISS, AIS) lack specificity for isolated thoracic injury, creating a niche for more focused prognostic tools.

Two promising models have emerged: the STUMBL Score-based on age, number of rib fractures, chronic lung disease, pre-injury anticoagulant use, and oxygen saturation-is explicitly designed for blunt chest trauma prognosis. Studies report strong discriminatory performance, with development-phase c-index up to 0.96 . External validations vary: one UK cohort showed STUMBL ≥ 11 had a sensitivity of 79%, specificity of 78%, and AUC of 0.84-comparable to clinician judgment ; Italian data demonstrated excellent discrimination (C-index ~0.90) and calibration .

The Thoracic Trauma Severity Score (TTSS), initially validated in polytrauma ICU patients, yields moderate to good discrimination (c-indices 0.72-0.85) across validation studies .

Though these scores show promise, high methodological bias and limited external validations temper their widespread adoption . A direct, comparative analysis of STUMBL and TTSS within a well-defined patient cohort is thus needed.

Inclusion Criteria:

• Adult patients (≥18 years) presenting with blunt chest trauma.
• Patients who have given written informed consent to participate in the study

Exclusion Criteria:

• Penetrating chest injuries
• Pediatric patients (<18 years)
• Patients with incomplete records or who decline consent
• Pregnant women
• Disturbed conscious patients
• Mechanically ventilated patients
• Polytrauma patients