Surgeon Volume and Social Disparity are Associated with Postoperative Complications After Lumbar Fusion

To characterize the volume dependence of both facilities and surgeons on postoperative complications after lumbar fusion and characterize the role of socioeconomic status.

Adults who underwent lumbar fusion from 2011 to 2015 were identified using International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic codes for lumbar disc degeneration or spondylolisthesis and procedure codes for lumbar fusion in the New York Statewide Planning and Research Cooperative System database. Complications were compared across surgeon and facility volumes using multivariable Cox proportional hazards regression, controlling for patient demographic and clinical factors. Surgeon and facility volumes were compared between the lowest and highest 20%.

Of the 26,211 patients identified with a lumbar fusion, 16,377 patients were treated at a high-volume or low-volume facility or by a high-volume or low-volume surgeon. Low-volume facilities had higher 3-month and 12-month rates of readmission, pneumonia, and cellulitis; lower 1-month, 3-month, and 12-month rates of deep vein thrombosis; and lower 1-month rates of wound complications. Low-volume surgeons had higher 1-month, 3-month, and 12-month rates of readmission, acute renal failure, surgical site infection, and wound complications; high 1-month and 3-month rates of urinary tract infection and pulmonary embolism; and a lower 12-month rate of revision. Patients who were treated by low-volume surgeons and had complications were more concentrated to ZIP codes with high social deprivation.

Both high-volume facilities and high-volume surgeons show lower rates of complications and readmission. There are significant socioeconomic disparities regarding which patients can access high-volume surgeons.