Contributor: Nick Tsipis MD
Educational Pearls:
The scaphoid bone is the most proximal carpal bone just distal to the radius
Fractures of the scaphoid bone are sometimes missed by plain X-rays
A 2020 review found a 21.8% incidence of missed scaphoid fractures later diagnosed by advanced imaging modalities
Only MRI has a sensitivity above 90% for diagnosing scaphoid fractures
Sensitivity of plain-film radiography is low unless it is a displaced fracture
Physical examination techniques fail to definitively rule out scaphoid fractures
Tenderness of the anatomical snuffbox has a sensitivity of 92.1% and specificity of 48.4%; i.e. absence reduces the likelihood of an occult scaphoid fracture but does not rule it out
Another common physical exam maneuver is pain with ulnar deviation, which carries a sensitivity of 55.2% and specificity of 76.4%.
Elicitation of pain with supination against resistance demonstrated a sensitivity of 100% and specificity of 97.9% in the study, so the authors recommend externally validating this method
Patients should be counseled on the importance of follow-up given that a fracture may not show up on imaging unless an MRI or repeat XR is done
References
1. Bäcker HC, Wu CH, Strauch RJ. Systematic Review of Diagnosis of Clinically Suspected Scaphoid Fractures. J Wrist Surg. 2020;09(01):081-089. doi:10.1055/s-0039-1693147
2. Coventry L, Oldrini I, Dean B, Novak A, Duckworth A, Metcalfe D. Which clinical features best predict occult scaphoid fractures? A systematic review of diagnostic test accuracy studies. Emerg Med J. 2023;40(8):576 LP - 582. doi:10.1136/emermed-2023-213119
Summarized by Jorge Chalit, OMSII | Edited by Meg Joyce & Jorge Chalit, OMSII