Body mass index and height in patients requiring surgery for lumbar intervertebral disc herniation.

The immediate preoperative body mass index and standing body height of 1128 patients who underwent surgery for lumbar intervertebral disc herniation were compared in a cross-sectional study with the corresponding values obtained from a general population sample. The material was divided into sex- and age-specific subgroups. To delineate possible differences, the 99% confidence intervals for the anthropometric mean values were constructed instead of hypothesis testing. With the exception of the oldest age group, from 50 to 59 years, the patients who underwent surgery for a disc herniation were more obese and taller than the population on average in all other sex- and age-specific subgroups. The major contrast emerged in women aged 20-29 years, in whom the 99% confidence interval for the mean body mass index of the patients undergoing surgery on was 25.1-27.3 kg/m2 versus 22.3-23.1 kg/m2 in the general population. In patients aged 20-39 years the mean body mass index was increased also when the body height of the patients was less than the mean value of the general population samples. Both an increased body mass index and a tall stature seem to have a clear association with those severe lumbar intervertebral disc herniations that require operative treatment.