Do supine oblique views provide better imaging of the cervicothoracic junction than swimmer's views?

OBJECTIVE To determine whether a swimmer's view or supine (trauma) oblique views are more likely to visualise the lower cervical spine when a lateral view fails to show the cervicothoracic junction. DESIGN A prospective study comparing two 20 week periods. In the first phase the swimmer's view was performed as an additional view when the cervicothoracic junction was not demonstrated. In the second phase paired supine oblique views replaced the swimmer's view. RESULTS 230 patients were included in the first phase, of whom 60 required swimmer's views. In the second phase 62 of 197 patients required supine oblique views. Radiology analysis of 53 pairs of supine oblique views showed that the vertebral bodies were adequately demonstrated at the cervicothoracic junction in only 20 patients (38%) compared with 22 in the swimmer's group (37%). The facet joints and posterior elements were, however, clearly seen in 37 (70%) of the supine oblique patients compared with 22 (37%) of the swimmer's group (p < 0.001, chi2 test). Exposure dose calculations showed a substantial reduction for a pair of supine oblique views (1.6 mGy) over a single swimmer's view (7.2 mGy). CONCLUSIONS In injured patients for whom the standard three view series fails to demonstrate the cervicothoracic junction, swimmer's views and supine oblique views show the alignment of the vertebral bodies with equal frequency. However, supine oblique films are safer, expose patients to less radiation, and are more often successful in demonstrating the posterior elements.