1. The results of wide laminectomy of the fifth lumbar vertebra and disc excision in 132 patients are reviewed and compared with some published results of the interlaminar operation.

2. There was no significant difference in either the immediate or the long-term results of the two operations suggesting that post-operative morbidity was not related to operative technique.

3. The incidence of post-operative back pain was found to increase with age at operation, duration of pre-operative symptoms and length of follow-up, and supported the impression that backache is predominantly a feature of the underlying degenerative process rather than the incidental operation.

4. The significance of recurrent disc lesions is discussed. Recurrence usually occurred at the previously cleared disc space and was thought to indicate incomplete degeneration of the disc at the time of the original operation.

5. The place of fusion combined with disc excision is discussed. No reliable indications for coincident fusion were found in this series.

6. The value of radiography is discussed. Plain radiographs were essential before operation to exclude other causes of backache and sciatica; otherwise they were of little value. Motion radiographs were no more helpful and myelography was used only when the level of the lesion was in doubt.

7. The risk of an acute cauda equina lesion following manipulation of a prolapsed lumbar disc is noted and the danger of manipulation, unless facilities for emergency surgery are available, is stressed.