Risk of Lumbar Degeneration After Spinal Fusion Varies
L4/5 fusions associated with highest risk of adjacent segment degeneration
MONDAY, April 14 (HealthDay News) -- In patients undergoing low lumbar spinal fusions, floating L4/5 fusions are more likely to result in degenerative changes in adjacent segments than L4/S1 or L5/S1 fusions, according to an article published in Journal of Spinal Disorders & Techniques in April.
Alexander Carl Disch, M.D., of Charite-University Medicine Berlin in Berlin, Germany, and colleagues investigated long-term outcomes of monosegmental and bisegmental fusions at the lumbar L4-S1 region, following 102 patients for a mean of 14 years (range three to 22 years) after surgery.
The researchers report overall positive results, with average Oswestry-Disability Index (ODI) scores of 26 percent at follow-up. Visual Analog Scale scores averaged 2.7 post-operatively, and rose to 3.6 at latest follow-up. The risk of radiologic adjacent segment degeneration (ASD) was significantly lower in patients who underwent L5/S1 fusions or bisegmental L4-S1 fusions compared to those with L4/5 fusions. Patients with ASD also showed reductions in sacral inclinations and lumbar lordosis angles and higher ODI values compared to those without ASD.
"We conclude that floating fusions of single low lumbar segments are more likely to result in ASD and are negatively influenced by sagittal plane abnormalities," the authors write.