Abstract
1. Some of the more common and obvious clinical syndromes arising from mechanical and degenerative derangements of the lumbar spine are defined.
2. Some principles in the selection of cases for surgical treatment are discussed and it is stressed how small a part operative intervention plays in the overall problem of low back derangement.
3. Details of surgical technique in the eight types of syndrome are described from past experience in the author's clinic, but not without recognition of the fluidity of this comparatively new field and its continuing evolution.