Rate of Second Spine Operations
Chronic low back pain may require surgery to remove a herniated disc or fuse an unstable spine. Removing the disc is called a discectomy or decompression. The hope is to avoid any further operations.

In this study, researchers from the University of Washington review the records of patients who had decompressive or fusion surgery from 1990 to 1993. Data was gathered for the next 11 years. The number of reoperations needed was added up and compared for these two groups.

They found nearly a 20 per cent rate of reoperation for both groups combined. Some conditions were more likely than others to develop complications requiring another operation. For example patients with spondylolisthesis had better outcomes after a fusion compared to decompression alone. Spondylolisthesis occurs when a fracture in the vertebral structure allows the main body of the bone to slide forward over the vertebra below it.

And for other conditions such as herniated discs, spinal stenosis, or a degenerative disc disease, decompression had better results with fewer reoperations compared to spinal fusion.

There were some factors that predicted a greater chance of reoperation. For example, patients with workers' compensation were more likely to have a reoperation compared to patients covered by private health insurance. Older patients (60 years old and older) were less likely to have a second operation.

The authors conclude that in general, the number of reoperations after lumbar spine surgery was significant. They suggest the lower reoperation rate after fusion was due to the surgeon giving the bone graft a longer time to heal before considering a second operation.

More than half of the reoperations after fusion were required because of problems with hardware used to stabilize the spine or because movement occurred where the fusion was supposed to prevent motion.
References
Brook I. Martin, MPH, et al. Reoperation Rates Following Lumbar Spine Surgery and the Influence of Spinal Fusion Procedures. In Spine. February 1, 2007. Vol. 32. No. 3. Pp. 382-387.