TL;DR
Get health and wellness essentials delivered free with Prime
- Fast, free delivery on millions of items
- Prime Video, Amazon Music and more included
- Member-only deals all year
A Norwegian national registry analysis found no statistically significant difference in disability after 12 months between patients who had spinal decompression alone and those who also had spinal fusion. Fusion was associated with longer operations and hospital stays, and a higher overall risk of complications, but the study’s observational design and one-year follow-up leave some questions open.
A study using Norwegian national registry data found no statistically significant difference in disability 12 months after surgery between patients who had spinal decompression alone and those who also had spinal fusion. The analysis covered 2,252 patients with degenerative spondylolisthesis and spinal stenosis, conditions for which fusion is commonly added to surgery, despite continuing debate over its benefits.
Researchers compared outcomes for 1,446 patients treated with decompression alone and 806 who also received fusion. Decompression relieves pressure on nerves in the spine; fusion joins vertebrae together. At one year, the average Oswestry Disability Index (ODI) score was 22.3 after decompression alone and 20.0 after fusion. The score measures pain-related disability, with higher scores indicating worse symptoms and a maximum of 50. The estimated difference was 2.2 points, with a 95% confidence interval of -1.6 to 6.1, and was not statistically significant.
The study used a target trial emulation approach, applying registry data to compare groups as if they had been in a trial. The researchers identified about 3,900 patients who had surgery for degenerative spondylolisthesis between 2007 and 2021, then excluded some patients, including those who were very elderly or had previous surgery in the same spinal area. The final analysis included 236 people who had also participated in the earlier NORDSTEN-DS trial. The average age was about 65, and roughly 70% of participants were women.
Fusion was associated with a mean 85 minutes more operating time and a hospital stay averaging 1.9 days longer than decompression alone. The report said no individual complication was clearly more common, but the overall risk of any complication was about twice as high in the fusion group; the risk of further surgery due to complications was higher still. These are findings from the study, not proof that fusion caused every difference, because treatment was not randomly assigned in this registry analysis.
Study Finds No Significant One-Year Disability Difference
The analysis found no statistically significant difference in disability at one year between patients who underwent decompression alone and those who also had fusion. Fusion was associated with longer surgery and hospitalization and a higher overall complication risk. Because the study was observational, it cannot establish that fusion caused these differences.
The findings are consistent with prior trials in Sweden and Norway that reported no disability improvement from adding fusion. A smaller U.S. study also found no such improvement, although it reported better quality of life with fusion. The registry study does not establish whether fusion is beneficial for particular patients or longer-term outcomes.
Products Worth Considering
Hyperice Normatec 3 Leg Compression Boots – Full Leg Recovery, Standard Size
Oral-B iO Series 9 Limited Rechargeable Electric Toothbrush with 7 Cleaning Modes
Therabody Theragun Mini 3rd Generation Massage Gun, Black
As an affiliate, we earn on qualifying purchases.
Why Surgeons Add Spinal Fusion
Degenerative spondylolisthesis occurs when one vertebra shifts forward relative to the vertebra below it and can accompany spinal stenosis, a narrowing that may put pressure on nerves. Some surgeons have regarded the slippage as a sign of instability and added fusion to decompression to stabilize the area. The study authors said that reasoning is plausible, but evidence of added benefit has been mixed.
Fusion remains common in some countries despite that uncertainty. A 2023 analysis cited in the report found that 90% of U.S. operations for degenerative spondylolisthesis in 2019 included fusion, 23 percentage points more than three years earlier. The Norwegian researchers offered no explanation for the increase. The earlier analysis’s authors cited possible factors including financial incentives, limited guidelines or regulations, and delays in sharing evidence through medical education and professional groups.
“This study calls into question the highly prevalent management of pain from lumbar degenerative spondylolisthesis with fusion.”
— James H. McAuley and colleagues
Limits of the One-Year Comparison
The study relied on administrative registry records, not random assignment to surgery types. Differences between patients chosen for fusion and those treated with decompression alone may have affected outcomes, including factors the records did not capture. The authors acknowledged the possibility of confounding by unmeasured variables.
The follow-up covered only 12 months, so the analysis cannot determine whether fusion might provide benefits or drawbacks over a longer period. The average result also does not rule out that particular patients could benefit: subgroup analyses based on factors such as age, sex, body mass index and symptom severity did not identify a group with significantly greater ODI improvement from fusion, but that finding is not definitive proof that no such group exists. The study also reported worse outcomes among men with obesity compared with men with lower body mass index, but that subgroup result does not establish why the difference occurred.
Guidelines and Longer Follow-Up
The researchers said the findings should prompt a reevaluation of current guidelines on fusion for lumbar degenerative spondylolisthesis. The report does not identify a scheduled guideline review or a specific policy change. The study adds registry-based evidence to the existing debate but does not provide a definitive answer for individual treatment decisions.
Longer-term follow-up and further research could clarify whether outcomes change after the first year and whether identifiable patient groups benefit from fusion. The study’s findings support discussion of the expected benefits, added procedure time, hospital stay and potential complications of each approach.
Key Questions
What did the Norwegian study find?
It found no statistically significant difference in disability at 12 months between patients who had decompression alone and those who also had spinal fusion.
What is spinal decompression?
Decompression surgery aims to relieve pressure on nerves in the spine. In this study, some patients also had fusion, a procedure that joins vertebrae together.
Did fusion have additional burdens in the study?
The fusion group had operations averaging 85 minutes longer and hospital stays averaging 1.9 days longer. The study also reported about twice the overall risk of any complication, though its observational design cannot prove that fusion caused every difference.
Does the study show fusion never helps?
No. It found no significant average disability advantage at one year in the analyzed groups. The authors noted that the 12-month follow-up leaves longer-term outcomes uncertain, and registry comparisons cannot answer every question about individual patients.
What are the main limitations?
The analysis used administrative records rather than random assignment, so unmeasured differences between patients may have affected results. It also followed outcomes for one year only, leaving possible longer-term effects unresolved.
Source: medpagetoday.com
