Early CT Compared With Bone Scintigraphy in Suspected Schapoid Fractures

Abstract

i cine published our study, examining whether multidetector CT is superior to bone scintigraphy for diagnosing radiographically occult scaphoid fractures. 1 Based on the results in this consecutive series of 100 patients, we could not confirm that early CT is superior to bone scintigraphy for suspected scaphoid fractures.We initially stopped after inclusion of 100 patients. However, throughout the following period, we were fortunate enough to continue inclusions to 159 patients. With this extended group of patients, we were able to provide more significant results. We would like to present the final results of our study to the readers of Clinical Nuclear Medicine. The design of the study is described in our previous publication. 1 In a period of 39 months, a total number of 159 consecutive patients with a suspected scaphoid fracture visited the emergency department, 79 of whom were male and 80 were female, with a mean age of 41 years (range, 17Y88 y).CT scans showed 15 scaphoid and 35 other fractures. Bone scintigraphy showed 28 scaphoid and 57 other fractures. According to the reference standard, there were 20 scaphoid fractures. One CT scan was false-positive and CT missed 6 scaphoid fractures. Bone scintigraphy was false-positive in 9 cases and missed 1 scaphoid fracture.CT had a sensitivity of 70%, specificity of 99%, accuracy of 96%, a positive predictive value of 93%, and a negative predictive value of 96%. Bone scintigraphy had a sensitivity of 95%, specificity of 94%, accuracy of 94%, a positive predictive value of 68%, and a negative predictive value of 99%.The percentages of sensitivity, specificity, and correct predictions (accuracy) were compared for the 2 diagnostic methods with a McNemar test. Although the sensitivity of CT seemed to be lower (70%) than that of bone scintigraphy (95%), this could not be confirmed statistically (P = 0.13), probably because of the small number of scaphoid fractures (n = 20). Accuracy did not differ significantly either between CT and bone scintigraphy (P = 0.63). The specificity of CT was significantly better than that of bone scintigraphy (P = 0.02). On the basis of these results, CT seems the investigation of choice for ruling in, and bone scintigraphy for ruling out, a scaphoid fracture in clinically suspected patients.In conclusion, after increasing the power of our study with additional data, our previous statement is confirmed that early CT imaging is not superior to bone scintigraphy for suspected scaphoid fractures. REFERENCE 1. Rhemrev SJ, de Zwart AD, Kingma LM, et al. Early computed tomography compared with bone scintigraphy in suspected scaphoid fractures. Clin Nucl Med. 2010;35:931Y934.

Diagnostic Work-up for Suspected Scaphoid Fractures

“…The search resulted in the identification of 64 potentially eligible articles, for which (where possible) full reports were obtained. Upon study selection, we included 11 studies (16,18,21,36,(39)(40)(41)(42)(43)(44)(45); and 45 studies were excluded, one of which was published in two reports (46). There were no ongoing trials or studies awaiting classification.…”

“…Four studies evaluated CT (16,36,41,42); five studies evaluated MRI (16,18,36,40,44); and six studies evaluated BS (21, 39-41, 43, 45). Of these studies, two compared CT with MRI (16,36); one study compared BS with CT (41); and one compared MRI with BS (40).…”

“…Seven studies assessed patients within 72 hours of the patient injuring their wrist; four studies did not report the timing of presentation to the emergency department (18,39,43,45). In seven studies, the index test was performed within 10 days of trauma (16,18,36,(39)(40)(41)(42).…”

“…Tenderness in the anatomical snuffbox was clearly incorporated in clinical evaluation in six studies (16,18,21,(40)(41)(42). One study reported 'pain over the scaphoid' as being clinically suspected (36).…”

“…Four studies did not define the content of clinical evaluation (39,(43)(44)(45). Images of BS were evaluated by a consultant clinical nuclear physician in four studies (21,40,41,44); three studies (two when BS was an index test, one when BS was a reference standard) did not provide the expertise of the observer(s) (39,43,45). For MRI and CT, evaluation was performed by at least one experienced radiologist.…”