Surprising Statistics About Knee and Hip Replacement Surgery Anthony M. DiGioia III, MD (from The Journal of Bone & Joint Surgery, Volume 89-A, Number 12, December 2007) Increasing case numbers The upward trends in the utilization of total hip and knee replacement between 1969 and 2003 detail the national need for these procedures. Some Statistics The age and gender-adjusted incidence per 100,000 person-years significantly increased from 1971 to 2003, representing a greater than 400% increase in the incidence of total knee replacement (as compared with a 55% increase in total hip replacement during the same period). There was a significantly higher utilization rate for women. The incidence increased with the patient's age for total knee replacement, except in patients more than eighty years old. The largest percentage increase was in patients less than fifty years old. There was a significant increase in the proportion of total knee replacements performed for the treatment of osteoarthritis, from 51% during 1971-1975 to 92% in 2000- 2003. This also reflects a reduction in the incidence of total knee replacements performed for the treatment of rheumatoid arthritis over the same period. It is projected that the number of primary total knee replacements will increase from 450,400 to 3.48 million by 2030, compared with a growth in the number of primary total hip replacements from 208,600 to 572,100 during the same interval. Revision in THRs The volume of revision total hip replacements is projected to grow from 40,800 in 2005 to 96,700 in 2030 (a 137% increase). Revision in TKRs The volume of revision total knee replacements is projected to grow from 38,300 in 2005 to 268, 200 in 2030 (a 600% increase). The future of TKR The continued and rapid growth of utilization of total knee replacement reflects a trend that will require additional resources in the future. This dramatically increased demand for replacement procedures will require additional discussions regarding the distribution of economic resources; the allocation of surgeons, facilities and resources; and improved operative efficiency. Additionally, given the growth in the number of procedures in the younger, more active patients, implant longevity will require further enhancement.