Efficacy of high resolution computed tomography for detection of early healing in scaphoid fractures

Background: While plain radiography is commonly used to assess scaphoid fracture, this imaging modality may not accurately demonstrate early bone healing. This investigation evaluates the utility of 64-slice CT in the detection of early fracture healing compared to plain radiographs and magnetic resonance imaging (MRI). Methods: Outpatients attending follow-up visits for scaphoid fractures at Hamilton General Hospital were included in this investigation. Inclusion criteria included outpatients over age of 18 who consented to attend a follow-up visit for the scaphoid fracture at 6 weeks for X-Ray, 64-slice CT and MRI scan to monitor fracture healing. Assessment of healing was independently interpreted by two radiologists specialized in musculoskeletal imaging. A total of 7 adult outpatients were accrued, with each case classified as healing, not healing, or equivocal for plain radiography and 64-slice CT scan. Results: For plain radiographs, the level of interrater agreement for evidence of healing was 57% (4/7) cases. When comparing this to CT scans, there was no discrepancy between radiologists as 100% (7/7) were found to have evidence of healing. The 64-slice CT scan demonstrated evidence of early trabecular continuity in all cases, including radiographs that were interpreted as equivocal. Conclusion: This study can be considered a pilot project for the efficacy of 64-slice CT in the assessment of early healing of scaphoid fractures. For clinicians, the multiplanar reconstruction images allows for more accurate assessment of fractures than plain radiography. CT scans are able to penetrate through bony callus that may obscure visualization of healing in plain radiography, demonstrate trabecular continuity better than plain radiographs, are readily accessible and provide faster imaging acquisition. The observations from this study may have implications in terms of duration and type of casting applied, timing of strengthening exercises, and avoiding unnecessary surgery which affect patient morbidity and cost of care.