[Surgery of disk hernia of the lumbar vertebral canal].

53 foraminal lumbar disc herniations have been operated on with 4 surgical different exposures: The classical interlaminar exposure (3 observations), with partial medial foraminotomy, does not allow a good view. The complete facetectomy (36 observations) exposes the foramen well but has a little risk of destabilisation. The external exposure (5 observations), lateral to the facets, seems to be a better approach. But, the "mixed" exposure (9 observations), by adding to the external exposure the interlaminar approach, is necessary when a part of the herniation is more medial.