Increased duration of overlap during lumbar fusion not associated with inferior outcomes
According to published results, increasing the duration of overlap did not lead to any inferior short-term outcomes in patients undergoing overlapping, single-level, posterior lumbar fusion.
Researchers performed a retrospective analysis of data for 1,302 adults who underwent overlapping, single-level, posterior lumbar fusion at a single, multicenter, academic health system. They compared exact-matched cohorts of the top 10% of patients with the longest duration of overlap (n = 131) and the bottom 40% of patients with the shortest duration of overlap (n = 520). They also performed univariate analysis on a demographic-matched cohort and a surgeon-matched cohort.

According to the study, outcome measures included 30-day ED visits, readmission, reoperation, mortality, morbidity and overall complications. The amount of overlap was calculated as a percentage of total overlap time.
Among all 1,302 patients, an increased duration of overlap was not associated with any short-term outcomes. After comparing exact-matched patients with the longest and shortest duration of overlap, the researchers also found no significant differences in any short-term outcome.
“Increasing duration of overlap, in the setting studied, does not lead to adverse short-term outcomes following single-level, posterior-only lumbar fusion,” the researchers wrote in the study. “Further studies should evaluate longer-term patient outcomes among patients with increased amounts of overlap during lumbar fusion and other neurosurgical procedures,” they concluded.