Comparison of conventional radiography and MDCT in suspected scaphoid fractures

Abstract

Aim: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography (MDCT) in suspected scaphoid fractures.

Methods: One hundred twenty-four consecutive patients were enrolled in our study who had suffered from a wrist trauma and showed typical clinical symptoms suspicious of an acute scaphoid fracture. All patients had initially undergone conventional radiography. Subsequent MDCT was performed within 10 d because of persisting clinical symptoms. Using the MDCT data as the reference standard, a fourfold table was used to classify the test results. The effective dose and impaired energy were assessed in order to compare the radiation burden of the two techniques. The Wilcoxon test was performed to compare the two diagnostic modalities.

Results: Conventional radiography showed 34 acute fractures of the scaphoid in 124 patients (42.2%). Subsequent MDCT revealed a total of 42 scaphoid fractures. The sensitivity of conventional radiography for scaphoid fracture detection was 42.8% and its specificity was 80% resulting in an overall accuracy of 59.6%. Conventional radiography was significantly inferior to MDCT (P < 0.01) concerning scaphoid fracture detection. The mean effective dose of MDCT was 0.1 mSv compared to 0.002 mSv of conventional radiography.

Conclusion: Conventional radiography is insufficient for accurate scaphoid fracture detection. Regarding the almost negligible effective dose, MDCT should serve as the first imaging modality in wrist trauma.

Keywords: Biplane radiography; Diagnostic accuracy; Dose calculation; Emergency radiology; Multidetector computed tomography; Musculoskeletal imaging; Scaphoid fracture; Wrist trauma.

Figure 1

Non-dislocated fissural fracture of the scaphoid that had not been detected by initial conventional radiography (A and B). Cross-sectional multidetector computed tomography clearly depicted the oblique fissural fracture line in the middle third of the scaphoid with coronal (C) and sagittal (D) reformation on the same day.

Figure 2

Diagonal fracture line of the scaphoid detected by conventional radiography (A and B) and subsequently confirmed by multidetector computed tomography (C and D) for preoperative planning.

Figure 3

Conventional radiography (A and B) and multidetector computed tomography (C and D) revealed an acute hamate fracture as a secondary finding.