THE STRAIGHT CERVICAL-SPINE - DOES IT INDICATE MUSCLE SPASM

The loss of cervical lordosis in radiographs of patients presenting wi th neck pain is sometimes ascribed to muscle spasm. We performed a cro ss-sectional study of the prevalence of 'straight' cervical spines in three populations: 83 patients presenting to an accident department wi th acute neck pain, 83 referred to a radiology department with chronic neck problems, and 80 radiographs from a normal population survey car ried out in 1958. Curvature was assessed on lateral radiographs both s ubjectively and by measurement. The prevalence of'straight' cervical s pines was 19% in the acute cases and 26% in the chronic cases. The 95% confidence interval for the difference was -6.4% to +19.3 %. In the n ormal population 42% showed a straight spine, but a further third of t hese films had been taken in a position of cervical kyphosis; this pro bably reflects a difference in positioning technique. Women were more likely than men to have a straight cervical spine, with an odds ratio of 2.81 (95 % CI 1.23 to 6.44). Our results fail to support the hypoth esis that loss of cervical lordosis reflects muscle spasm caused by pa in in the neck.