- In low-risk groups with an adequate c-spine XRay, the negative predictive value is 99.9%. However, C-spine XRay sensitivity for all comers is only 36-64% and average time-to-dispo is 1.9 hours vs 1 hour on average for CT.
- CT c-spine disadvantages: Cancer risk 1:200 in 15 y/o, 1:2,000 in 30 y/o, 1:5,000 in 70 y/o. Cost is also higher, although when inadequate CSXR and "missed fracture" costs are added in they may be comparable.
- In the alert patient with a negative CT c-spine but persistent bony tenderness there are three options: continue collar upon discharge, MRI for ligamentous injury, or flex-extension films.