Background: Standardized surgery rates for common orthopedic procedures vary across geographical areas in Norway. We explored whether area-level factors related to demand and supply in publicly funded healthcare are associated with geographical variation in surgery rates for six common orthopedic procedures. Methods: The present study is a cross-sectional population-based study of hospital referral areas in Norway. We included adult admissions for arthroscopy for degenerative knee disease, arthroplasty for osteoarthritis of the knee and hip, surgical treatment for hip fracture, and decompression with/without fusion for lumbar disk herniation and lumbar spinal stenosis in 2012–2016. Variation in age and sex standardized rates was estimated using extremal quotients, coefficients of variation, and systematic components of variation (SCV). Associations between surgery rates and the socioeconomic factors urbanity, unemployment, low-income, high level of education, mortality, and number of surgeons and hospitals were explored with linear regression analyses. Results: Knee arthroscopy showed highest level of variation (SCV 10.3) and decreased in numbers. Variation was considerable for spine surgery (SCV 3.8–4.9), moderate to low for arthroplasty procedures (SCV 0.8–2.6), and small for hip fracture surgery (SCV 0.2). Higher rates of knee arthroscopy were associated with more orthopedic surgeons (adjusted coefficient 24.8, 95% confidence interval (CI): 2.7–47.0), and less urban population (adjusted coefficient −13.3, 95% CI: −25.4 to −1.2). Higher spine surgery rates were associated with more hospitals (adjusted coefficient 22.4, 95% CI: 4.6–40.2), more urban population (adjusted coefficient 2.1, 95% CI: 0.4–3.8), and lower mortality (adjusted coefficient −192.6, 95% CI: −384.2 to −1.1). Rates for arthroplasty and hip fracture surgery were not associated with supply/demand factors included. Conclusions: Arthroscopy for degenerative knee disease decreased in line with guidelines, but showed high variation of surgery rates. Socioeconomic factors included in this study did not explain geographical variation in orthopedic surgery.

BackgroundStandardised surgery rates for common orthopedic procedures vary across geographical areas in Norway. The aim in this study is to explore whether area-level factors related to demand and supply in publicly funded healthcare are associated with geographical variation in surgery rates for six common orthopedic procedures. MethodsCross-sectional population based study of the 19 hospital referral areas in Norway. Adult admissions for arthroscopy for degenerative knee disease, arthroplasty for osteoarthritis of the knee and hip, surgical treatment for hip fracture, and decompression with or without fusion for lumbar disc herniation and lumbar spinal stenosis over 5 years (2012-2016) were included. Extremal quotients, coefficients of variation and systematic components of variance were used to estimate variation in age and sex standardised surgery rates. Linear regression analyses were conducted to explore the association between standardised surgery rates and proportion of population in urban areas, unemployment, proportion of persons living in low-income households, proportion of persons with a high level of education, and mortality. ResultsArthroscopy for degenerative knee disease showed the highest level of variation and the number of arthroscopies decreased during the period. There was considerable variation in procedures for lumbar disc herniation and lumbar spinal stenosis, moderate to low variation for arthroplasty for osteoarthritis of the knee and hip, and least variation in surgical treatment for hip fracture. Association between surgery rates and socioeconomic and supply factors were weak for arthroscopy for degenerative knee disease and decompression for lumbar disc herniation and spinal stenosis. Standardised surgery rates for arthroplasty for osteoarthritis of the knee and hip, and surgical treatment for hip fracture were not associated with the supply and demand factors included in this study.ConclusionsVariation in surgery rates were particularly high for arthroscopy for degenerative knee disease, and these rates decreased considerably during the five-year period. Factors reflecting socioeconomic circumstances, health and supply have a weak association to orthopedic surgery rates at an area-level. Whether this reflects the equity of universal health care services, or if area-level factors are not detailed enough to detect an existing association is being explored in two ongoing Norwegian studies.

Background and purposeStandardized surgery rates for common orthopedic procedures vary across geographical areas in Norway. We explored whether area-level factors related to demand and supply in publicly funded healthcare are associated with geographical variation in surgery rates for six common orthopedic procedures. Patients and methodsCross-sectional population based study of hospital referral areas in Norway. We included all adult admissions for arthroscopy for degenerative knee disease, arthroplasty for osteoarthritis of the knee and hip, surgical treatment for hip fracture, and decompression with or without fusion for lumbar disc herniation and lumbar spinal stenosis in 2012-2016, a total of 175,973 admissions. Variation in age and sex standardized rates was estimated using extremal quotients, coefficients of variation and systematic components of variance. Association between surgery rates and urbanity, unemployment, low-income, high level of education, and mortality, was explored with linear regression analyses. ResultsKnee arthroscopy showed highest level of variation (SCV 10.3) and decreased in numbers. Variation was considerable for spine surgery (3.8-4.9), moderate to low for arthroplasty procedures (0.8-2.6), and small for hip fracture surgery (0.2). Association between surgery rates and demand/supply factors were weak for knee arthroscopy and spine surgery. Rates for arthroplasty, and hip fracture surgery were not associated with supply/demand factors included.InterpretationArthroscopy for degenerative knee disease decreased in line with guidelines, but showed high variation of surgery rates. Factors reflecting supply/demand have a weak association to orthopedic surgery rates at area-level. Whether this reflects the equity of universal health care services, or if area-level factors are not detailed enough to detect an existing association, needs further exploring.