A Machine Learning Algorithm to Estimate the Probability of a True Scaphoid Fracture After Wrist Trauma

Anne Eva J. Bulstra, Machine Learning Consortium, Job N. Doornberg, Ruurd L. Jaarsma

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)

Abstract

Purpose: To identify predictors of a true scaphoid fracture among patients with radial wrist pain following acute trauma, train 5 machine learning (ML) algorithms in predicting scaphoid fracture probability, and design a decision rule to initiate advanced imaging in high-risk patients. 

Methods: Two prospective cohorts including 422 patients with radial wrist pain following wrist trauma were combined. There were 117 scaphoid fractures (28%) confirmed on computed tomography, magnetic resonance imaging, or radiographs. Eighteen fractures (15%) were occult. Predictors of a scaphoid fracture were identified among demographics, mechanism of injury and examination maneuvers. Five ML-algorithms were trained in calculating scaphoid fracture probability. ML-algorithms were assessed on ability to discriminate between patients with and without a fracture (area under the receiver operating characteristic curve), agreement between observed and predicted probabilities (calibration), and overall performance (Brier score). The best performing ML-algorithm was incorporated into a probability calculator. A decision rule was proposed to initiate advanced imaging among patients with negative radiographs. 

Results: Pain over the scaphoid on ulnar deviation, sex, age, and mechanism of injury were most strongly associated with a true scaphoid fracture. The best performing ML-algorithm yielded an area under the receiver operating characteristic curve, calibration slope, intercept, and Brier score of 0.77, 0.84, −0.01 and 0.159, respectively. The ML-derived decision rule proposes to initiate advanced imaging in patients with radial-sided wrist pain, negative radiographs, and a fracture probability of ≥10%. When applied to our cohort, this would yield 100% sensitivity, 38% specificity, and would have reduced the number of patients undergoing advanced imaging by 36% without missing a fracture. 

Conclusions: The ML-algorithm accurately calculated scaphoid fracture probability based on scaphoid pain on ulnar deviation, sex, age, and mechanism of injury. The ML-decision rule may reduce the number of patients undergoing advanced imaging by a third with a small risk of missing a fracture. External validation is required before implementation. 

Type of study/level of evidence: Diagnostic II.

Original languageEnglish
Pages (from-to)709-718
Number of pages10
JournalJournal of Hand Surgery
Volume47
Issue number8
Early online date3 Jun 2022
DOIs
Publication statusPublished - Aug 2022

Keywords

  • Algorithm
  • decision rule
  • fracture
  • machine learning
  • scaphoid

Fingerprint

Dive into the research topics of 'A Machine Learning Algorithm to Estimate the Probability of a True Scaphoid Fracture After Wrist Trauma'. Together they form a unique fingerprint.

Cite this