Surgery rates for lumbar spinal stenosis in Denmark between 2002 and 2018: a registry-based study of 43,454 patients.

BACKGROUND AND PURPOSE: Over the last decades, many countries have shown increased surgery rates for lumbar spinal stenosis (LSS), but little information is available from Denmark. We describe the development in diagnosis and surgery of LSS in Denmark between 2002 and 2018. PATIENTS AND METHODS: We collected diagnostic ICD10-codes and surgical procedure codes from private and public hospitals in Denmark from the Danish National Patient Register. Patients diagnosed with LSS and those with surgical procedure codes for decompression surgery with or without fusion were identified. Annual surgery rates were stratified by age, sex, and type of surgery. RESULTS: During these 17 years, 132,138 patients diagnosed with LSS and 43,454 surgical procedures for LSS were identified. The number of surgical procedures increased by 144%, from 23 to 56 per 100,000 inhabitants. The proportion of patients diagnosed with LSS who received surgery was about 33%, which was almost stable over time. Decompression without fusion increased by 128% from 18 to 40 per 100,000 inhabitants and decompression with fusion increased by 199%, from 5 to 15 per 100,000. INTERPRETATION: Both the prevalence of LSS diagnoses and LSS surgery rates more than doubled in Denmark between 2002 and 2018. However, the proportion of patients diagnosed with LSS who received surgery remained stable. Decompression surgery with fusion increased at a higher rate than decompression without fusion, although recent evidence suggests no advantage of decompression plus fusion over decompression alone.