Back pain from degenerative disc disease can be very disabling for older adults. In this study, orthopedic surgeons show how a simple spinal fusion can make a big difference. The surgeons fused a single spinal level of 224 patients and then followed them for two years to see the results. The group was divided into two groups by age. Anyone younger than 65 years was in the first group. Patients 65 years old and older were in the second group.
Medicare has asked for more proof that spinal arthrodesis (fusion) in older adults really helps. Until now, most of the studies reported on younger adults. And age could make a difference. We can’t just assume that the results of this procedure in younger adults would be the same in older adults. An advisory committee from the Centers for Medicare and Medicaid Services asked for conclusive evidence to support the use of spinal fusion in patients 65 years of age or older. This age-group includes the Medicare population.
The operation performed was a single-level posterolateral lumbar arthrodesis with iliac crest bone graft. Posterolateral refers to the direction (back and side) that the fusion was done. Iliac crest bone graft comes from the top of the pelvic bone. Instrumentation (rod and screws) were used to hold the segment stable until bone filled in around the bone graft. The spinal level fused was slightly different between the two groups. The older patients’ fusion was in the L345 region. The younger patients were more likely to have a fusion at the L5-S1 level.
In general, the patients in each group were very similar (e.g., education, occupation, alcohol use, general health) except for age. Men and women were included. The main differences were that the younger patients rated their pain higher. They were more likely to still be working and a Worker’s Compensation claim. And the older patients were more likely to have advanced spine degeneration with bone spurs, thickened spinal ligaments, and facet (spine) joint degeneration.
Results were measured using several well-known research tools. These included the Oswestry Disability Index (ODI), the Medical Outcomes Study SF-36, and the numeric rating scale for back and leg pain. X-rays and CT scans were also used to look at the fusion site and see if it was successful or not. These imaging studies showed the presence of bone bridging the vertebral segment (a sign of successful fusion) and any cracks in the bone (a sign of weakness or instability).
Everyone in both groups had significant improvements in their test scores. But the older group demonstrated a larger change in scores indicating greater improvement compared to the younger patients. Complications in the early postoperative period (first 30 days) were higher among the older adults. Half of the older group had an adverse event after surgery. This was compared to one-third of the younger group. Most of the problems were minor but some patients had a heart attack, blood clot, or infection.
The authors concluded that older adults having a single level spinal fusion for degenerative disc disease can have a marked decrease in disability and improved health-related quality of life. The substantial benefit demonstrated in this study supports the use of this procedure for adults 65 years of age and older. The procedure is not without some potential complications, but overall it is safe and effective. Improvement seemed to occur even in those patients who had some type of problem after surgery.