Objective To develop and validate a Clinical Decision Rule (CDR) for paediatric finger trauma that reduces unnecessary radiographs while ensuring accurate identification of clinically significant fractures.

Design Observational, retrospective, single-center study. Medical records of patients aged 0–16 years presenting with finger trauma were reviewed to develop a CDR. Multivariate logistic regression analysis was performed to identify predictive variables. A diagnostic test study was then carried out to assess the performance of the developed CDR.

Setting paediatric emergency department of a secondary-level hospital.

Participants A total of 462 injured fingers from 411 patients.

Main Outcome Measures Sensitivity, specificity, positive and negative predictive values (PPV and NPV) for significant fractures; Absolute Risk Reduction (ARR), Relative Risk Reduction (RRR), and the Number Needed to Treat (NNT) for the reduction in X-rays requested and their 95% confidence interval (95% CI).

Results A total of 411 patients (462 injured fingers) were included, with a mean age of 10.13 years (standard desviation 3.70) and 57.9% being male. Overall, 8.01% of cases had a fracture, with a significantly higher prevalence in males (10.38% vs. 4.95%, p = 0.0328). Multivariate logistic regression identified deformity (adjusted Odds Ratio (OR): 2.33×102), mid/distal phalanx injury (OR: 15.40), impaired function (OR: 9.48), and hyperextension/flexion mechanism (OR: 5.37) as significant predictors. A CDR was developed with 100% sensitivity (95% CI 65.55 to 100) and 100% NPV (95% CI 98.11 to 100) for detecting clinically significant fractures. Applying the rule reduce 41.87% (ARR 95% CI: 36.20 to 47.55%) of radiographs, with an estimated annual cost saving of €2,650.

Conclusions This CDR is a reliable tool for identifying patients at risk of significant fractures in finger trauma. It safely reduces radiograph use, decreases radiation exposure, and optimizes healthcare costs. Further external validation through prospective studies is needed.

What is already known on this topic No validated clinical decision rule exists for paediatric finger trauma, despite the high frequency of such injuries and the frequent overuse of radiographs. While clinical decision rules in other anatomical regions (e.g., ankle, knee) have proven effective in reducing unnecessary imaging, similar tools have not been validated for hand trauma in children.

What this study adds This study proposes a clinical decision rule for paediatric finger trauma, based on a retrospective analysis. The rule demonstrated high diagnostic performance, with 100% sensitivity and negative predictive value for significant fractures, and could potentially reduce radiograph use by over 40%.

How this study might affect research, practice or policy Although external and prospective validation is still required, this clinical decision rule shows promise as a future tool to optimise decision-making in paediatric finger trauma. If validated, it may contribute to reduce unnecessary radiographs, improving emergency department workflow, and minimising radiation exposure in children.

The authors have declared no competing interest.

This study did not receive any funding

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethics committee of Hospital Universitario Infanta Leonor gave ethical approval for this work.

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All data produced in the present study are available upon reasonable request to the authors