The Association between Teaching Hospital Status and Postoperative Outcomes among Adults Undergoing Long-Segment Posterior Lumbar Instrumentation.

Abstract

Long-segment lumbar spine fusions (LSLF) are widely performed in the United States to address degenerative conditions, instability, and deformities but carry substantial risks of surgical and medical complications. With demand expected to rise alongside an aging population, understanding factors that influence outcomes is critical. Hospital teaching status may play a role, as academic centers offer multidisciplinary resources and trainee involvement, whereas non-academic hospitals may prioritize efficiency and patient flow. Prior studies across surgical disciplines, including spine surgery, have reported inconsistent findings, and few have comprehensively examined complication profiles after LSLF. This study evaluates the association between hospital teaching status and surgical, mechanical, and medical complications following LSLF, with readmission risk assessed as an exploratory outcome. To evaluate the association between hospital teaching status and short- and long-term outcomes following long-segment posterior lumbar spine procedures. Retrospective study utilizing the TriNetX Research Network. Patients who underwent posterior lumbar instrumentation spanning 3 to 12 vertebral segments for lumbar spinal stenosis, spondylolisthesis, or scoliosis. Primary outcomes included surgical complications (wound dehiscence, infection, reoperation) at 30 and 90 days postoperatively. Secondary outcomes assessed medical complications at 30 and 90 days, and pseudoarthrosis or mechanical failure at one and two years postoperatively. Exploratory outcomes were readmission rates at 30 and 90 days. The TriNetX Research Network was queried from January 1, 2010, to December 31, 2022. Patients were categorized by academic or non-academic treatment centers. Propensity score matching was used to control for age, gender, race, and comorbidities. Initially, 39,582 patients (8,506 non-academic, 31,076 academic) met criteria. Following 1:1 propensity score matching, each cohort consisted of 6,548 patients. No significant difference in surgical complication rates between academic and non-academic centers was observed at 30 days (OR = 0.950, 95% CI [0.823-1.097]) or 90 days (OR = 0.971, 95% CI [0.866-1.089]). Medical complication rates were similar at 30 days (OR = 1.022, 95% CI [0.897-1.165]) and 90 days (OR = 1.015, 95% CI [0.907-1.136]). At one year, patients at non-academic centers exhibited significantly higher odds of pseudoarthrosis or mechanical failure (OR = 1.314, 95% CI [1.213-1.423]), which persisted at two years postoperatively (OR = 1.265, 95% CI [1.171-1.367]). Exploratory analyses revealed significantly higher odds of readmission at both 30 days (OR = 2.211, 95% CI [2.044-2.390]) and 90 days (OR = 1.920, 95% CI [1.781-2.066]) for patients at non-academic centers. In this large-scale, propensity-matched retrospective analysis, non-academic centers demonstrated comparable short-term medical complication rates and surgical, but higher long-term risks of pseudoarthrosis or mechanical failure, and substantially increased readmission rates compared to academic centers. These findings highlight the influence of hospital teaching status on long-segment lumbar spine procedure outcomes and emphasize the need for improved perioperative management across different hospital settings.