Geographical variation in musculoskeletal surgical care in public hospitals in Ireland: a repeated cross-sectional study.

Objective: To examine the extent of geographical variation across musculoskeletal surgical procedures and associated factors in Ireland.

Design: Repeated cross-sectional study.

Setting: 36 public hospitals in Ireland.

Participants: Adult admissions for hip fracture, hip and knee replacement, knee arthroscopy and lumbar spine interventions over 5 years (2012-2016).

Primary Outcome Measure: Standardised discharge rate (SDR).

Analysis: Age and sex SDRs were calculated for 21 geographical areas. Extremal quotients, coefficients of variation and systematic components of variance were calculated. Linear regression analyses were conducted exploring the relationship between SDRs and year, unemployment, % urban population, number of referral hospitals, % on waiting lists>6 months and % with private health insurance for each procedure.

Results: Across 36 public hospitals, n=102 756 admissions were included. Hip fracture repair showed very low variation. Elective hip and knee procedures showed high variation in particular years, while variation for lumbar interventions was very high. Knee arthroscopy rates decreased over time. Higher unemployment was associated with knee and hip replacement rates and urban areas had lower hip replacement rates. Spinal procedure rates were associated with a lower number of referral hospitals in a region and spinal injection rates were associated with shorter waiting lists. A higher proportion of patients having private health insurance was associated with higher rates of hip and knee replacement and lumbar spinal procedures.

Conclusions: Variation and factors associated with SDRs for publicly funded hip and knee procedures are consistent with similar international research in this field. Further research should explore reasons for high rates of spinal injections and the impact of private practice on musculoskeletal procedure variation.