During a period of 4.5 years, 199 patients have been operated on by la
minectomy because of narrow lumbar canal. The incidence in Geneva is a
bout 11.5 case/100000/year and the ratio between male and female is 1.
28. The disease is strongly related to aging, but men are affected ear
lier in their life than women. Heavy work, particularly for men, has a
part to play in the genesis, like the body mass claculated by BMI (Bo
dy Mass Index). A comparison between the epidemiology of lumbar disc p
rolapse and lumbar stenosis shows the differences.