PHP116 - Incidence of Subsequent Lumbar Surgery Following Posterior Lumbar Fusion

Abstract

A procedural revision is a common event after an index posterior lumbar spinal fusion (PSF). However, there is little evidence on the characterization of any subsequent lumbar surgeries following index PSF. This study evaluates the incidence of and potential influencing factors associated with subsequent surgeries in the lumbar spine (SSLS) following PSF. Patients with ICD-9/10 codes for PSF of 1-2 spinal levels were identified in the Premier Healthcare Database®, 2013-2016. Patients were required to be from hospitals that continuously contributed data to the database for at least one year after index PSF. Patients’ demographics as well as clinical, procedural, hospital, and provider characteristics were collected and analyzed. The incidence of any SSLS within one year after PSF was estimated. Potential factors associated with SSLS were evaluated using logistic regression. 67,372 patients were identified. The majority of patients were female (56.1%), between the ages of 65-74 (28.9%), 80.4% were white, 59.7% were married, 46.9% had Medicare insurance, 91.4% had surgery at urban centers, and 54.2% at teaching hospitals. SSLS occurred in 2.10% of patients; 1.96% of patients returned for a PSF of 1-2 levels, while 0.27% returned for PSF of 3 or more levels, anterior fusion or non-fusion procedures. Variables associated with higher odds of SSLS included hospitals with 400-499 beds versus 500+ beds (adjusted Odds Ratio (OR); 95% Confidence Interval (CI): 1.3; 1.1, 1.6), history of hypertension (1.15; 1.0,1.3), history of neurological disorder (1.8; 1.4,2.3) and history of rheumatoid arthritis (1.3; 1.1,1.7), while age 75+ (0.66; 0.52,0.84) and commercial insurance versus non-commercial (0.78; 0.69,0.89) decreased the odds. Following PSF of 1-2 levels, most patients returning for SSLS undergo the same procedure as the index surgery. A combination of hospital and patient factors are associated with odds of SSLS.