Epidemiological trends in spine surgery over 10 years in a multicenter database

Kazuyoshi Kobayashi, Kei Ando, Yoshihiro Nishida, Naoki Ishiguro, Shiro Imagama

There are few epidemiological studies of spinal surgery in Asia and none in Japan. The goal of this study was to review spine surgeries performed in our group between 2004 and 2015 in a cross-sectional study, with a focus on the effects of the superaging society on the characteristics and trends of spinal surgeries. A retrospective review was performed for all 45,831 spinal surgeries conducted between 2004 and 2015 and recorded in our prospective multicenter database. During the study period, there was a significant increase in annual spine surgeries (p < 0.05). The proportion of elderly patients (aged ≥ 70) also increased, and the mean age at the time of surgery significantly increased from 54.6 years in 2004 to 63.7 years in 2015 (p < 0.05). Regarding the etiology, there were significant increases in degenerative disease (p < 0.01) and osteoporotic vertebral fracture, and a significant decrease in rheumatic spondylosis from 2004 to 2015 (p < 0.01). Instrumentation surgery increased over time, with the performance of MIS, BKP and LLIF as new procedures in recent years (p < 0.01). The mean reoperation rate was 2.0% and this rate did not change significantly over time, although the rate of reoperation due to surgical site infection significantly increased from 0.9 to 1.5% (p < 0.05). Our data showed marked increases in the number of spine surgeries, the age of patients, and the number of surgeries for degenerative diseases. This large-scale study provides indicators for planning the future development of spine surgery and for treatment of spinal diseases in daily practice. These slides can be retrieved under Electronic Supplementary Material.