Time trends in spine surgery in Italy: a nationwide, population-based study of 1,560,969 records of administrative health data from 2001 to 2019.

BACKGROUND AND PURPOSE: The use of spinal implants has increased substantially. Their widespread use raises public health concerns. We aimed to study spinal surgery trends in Italy from 2001 to 2019 and present a mapping for ICD9-CM codes potentially related to spinal diagnoses and procedures.

METHODS

ICD9-CM codes of interest were selected and mapped to clinically meaningful spinal diagnostic categories and procedure classes. The Italian National Hospital Discharge Records database was then browsed according to these codes. Surgical volumes and trends were described. Population incidence rates (IR) were estimated and provided with 95% confidence intervals (CI). Variations in IRs were reported in terms of incidence rate ratio. The statistical significance of counts and IR time series trends was assessed by using the Cox-Stuart test.

RESULTS

1,560,969 spinal procedures were extracted from 209,818,966 admissions registered nationally. The annual number of spinal procedures increased significantly by 67%, from 58,369 in 2001 to 97,636 in 2019 (P < 0.002). 1,040,326 (67%) procedures did not include implants, while 590,643 (33%) used implants, 395,450 (25%) associated with fusions and 125,193 (8%) with non-fusions. Population IRs increased from 100.9 (CI 100.1-101.7) to 163.2 (CI 162.2-164.3) episodes per 100,000 inhabitants. Surgical volumes for non-implant-related procedures remained stable, while implant-related procedures increased significantly, by 420% over the 19 observed years (P = 0.002).

CONCLUSION

Spinal surgical procedures and their population incidence rates increased significantly. Fusions and other implant-related procedures increased substantially for most diagnostic categories. An ICD9-CM mapping for spinal diagnoses and procedures as a reproducible tool for further explorations was presented.