In a retrospective study of 45,284 penetrating trauma patients, unadjusted mortality was twice as high in the 4.3% of  patients who underwent spine immobilisation, compared with those who were not immobilised.
An accompanying editorial comments: ‘The number needed to treat with spine immobilization to potentially benefit one penetrating trauma patient was 1,032. The number needed to harm with spine immobilization to potentially contribute to one death was 66.‘
Spine immobilization in penetrating trauma: more harm than good?
J Trauma. 2010 Jan;68(1):115-20