Surgery consists of spinal decompression for predominately leg pain problems. The most commonly performed surgery in older patients is the lumbar laminectomy. Total laminectomy is the procedure recommended for central canal stenosis. More commonly, central canal, lateral recess, and foraminal stenosis occur in the same patient. Lateral recess stenosis may be the major offending blockage in the canal. This may be treated with a total laminectomy or a bilateral medial facetectomy performed through the microscope with excellent decompression of the lateral recess. Foraminal stenosis can also be decompressed from a paraspinous position with the foraminotomy performed from the outside in. This can be combined with a microscopic medial facetectomy. Essentially, all these operations remove bone and redundant tissue to allow the nerve adequate freedom in the spinal canal and/or intervertebral foramina. Fusions are performed predominantly for degenerative spondylolisthesis to prevent the recurrence of radiculopathy. Internal fixation may be indicated in any situation in which the surgeon feels that the fusion rate is potentially compromised, but he or she must be aware that internal fixation does not guarantee spine fusion. Spinal instrumentation certainly increases the complication rate. The number of levels fused and the inclusion of the sacrum are important in predicting the fusion rate.