1454. 30-day Outcomes for Repeat Arthroplasty and Repeat Fusion Procedures in the Lumbar Spine: Insights from a National Registry

Authors: Mohamad Bydon, MD, FAANS ; Mohammed Ali Alvi, MD; Anshit Goyal, MD; Brett Freedman, MD; Bradford Currier, MD; Benjamin Elder, MD, PhD (Rochester, MN)

Introduction: Lumbar fusion is one of the most common surgical procedures which is employed for management of degenerative disc disease of lumbar spine. Lumbar disc arthroplasty (LDA) is a less-common alternative. Long-term reoperation rate for lumbar fusion and LDA in the literature range from 5-6% and 4-6%, respectively. However, not much is known about surgical and clinical outcomes of revision procedures after lumbar fusion and arthroplasty. Methods: We queried the National Surgical Quality Improvement Program (NSQIP) database for patients undergoing repeat lumbar fusion and arthroplasty procedures between 2012-2016. Patients with history of hybrid procedure (LDA plus fusion) at the index operation were excluded. Operative characteristics of each of these procedures were abstracted. Demographic characteristics, baseline clinical characteristics and 30-day clinical outcomes were compared between repeat fusion and arthroplasty procedures using univariate statistical analyses. Results: A total of 55 revision LDA were identified, of which 5.5% (n=3) were arthroplasty removal alone, 34.5% (n=19) were revision arthroplasty and 60% (n=33) were hybrid procedures (arthroplasty plus fusion). A total of 670 repeat fusion procedures were identified of which. Patients undergoing repeat arthroplasty procedures were found to be younger (52±14.2 vs 58.3±14.4,p<0.001), less likely to have a device related complication (9.1%vs22.5%, p<0.001), and more likely to have a degenerative disease (61.8% vs 29.2%,p<0.001). Repeat arthroplasty procedures were found to be more frequently performed as outpatient (12.7%,n=7 vs 1.6%,n=11,p<0.001), were associated with longer operative time (208.2±122 minutes vs 171.1±110.4 minutes,p=0.027). Length of stay, surgical site infection (SSI), readmission and reoperation rate did not differ between the two groups. Conclusion: We found that repeat arthroplasty procedures are more likely to be performed due to re-emergence of degenerative symptoms, compared to repeat fusion procedures which are more likely to be performed for device related complications.