[Trends in the number of knee and hip arthroplasties: considerably more knee and hip prostheses due to osteoarthritis in 2030].

Objective: To predict the future number of knee and hip arthroplasties due to osteoarthritis (OA) in the Netherlands based on historical trends and demographic projections.

Design: Data analysis and model calculations.

Method: Two future projections were based on age and sex-specific number of hospital admissions for the placement of total knee or hip prostheses due to OA between 1995 and 2005; data were obtained from the Dutch National Medical Registration (LMR). The demographical projection was based on the incidence of arthroplasty in 2005 combined with demographic predictions from Statistics Netherlands regarding the time period between 2005 and 2030. The trend projection used the trend in the age and sex-specific incidence of surgery between 1995 and 2005.

Results: Between 1995 and 2005, the annual number of knee arthroplasties in patients with a primary diagnose of OA increased from 4,916 to 14,565, an increase of 196%. The total number of hip arthroplasties increased from 13,785 to 20,715, an increase of 50%. The demographical projection suggests that the number of total hip arthroplasties will increase to 31,731 by 2030, an increase of 53%, and the number of knee arthroplasties to 22,183. The trend projection suggests that the numbers may increase to 51,680 for the hip (+149%) and to 57,893 for the knee (+297%).

Conclusion: The increase in the number of knee and hip arthroplasties due to OA will probably continue in the coming 20 years. The following developments will probably contribute to this: demographical changes, the increase in overweight, improved long-term outcomes of arthroplasty, more active lifestyle of the elderly and the increasing number of orthopaedic surgeons.