JAAOS - 2026-03-15 - Journal Article
Cost-Neutral Thresholds With Cementless Fixation in Total Knee Arthroplasty: A 20-Year Markov Analysis.
Booth M, Box H, Bedair H
Topics
Key Takeaway
Cementless TKA costs $256 more than cemented over 20 years, but becomes cost-neutral if implant markup is ≤19% or OR time savings reach 13 minutes.
Summary Depth
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Summary
This Markov decision model compared 20-year costs of cemented versus cementless primary TKA in a simulated cohort of 10,000 patients starting at age 50. Cementless TKA cost $20,829 versus $20,573 for cemented; however, a cementless failure hazard ratio of 0.8 produced $1,676 in savings, while a hazard ratio of 1.2 added $1,768 in cost. Cost neutrality was achievable with a 19% implant markup cap or 13 minutes of OR time saved, with OR time costs exceeding $54/minute driving additional savings.
Key Limitation
All model inputs—especially cementless revision rates—are drawn from heterogeneous published sources with variable follow-up, meaning the hazard ratio assumptions drive conclusions but cannot be validated within this study.
Original Abstract
BACKGROUND
Total knee arthroplasty (TKA) is increasingly performed in younger, high-demand patients, raising concerns about the long-term durability of traditional cemented implants. Noncemented TKA offers the potential for biologic fixation and improved longevity, but its cost-effectiveness remains uncertain.
METHODS
A Markov decision model was used to compare the 20-year cost of cemented versus noncemented primary TKA in a cohort of 10,000 patients beginning at age 50 years. The model incorporated implant costs, revision rates, operating room (OR) time, and other relevant clinical variables. Sensitivity analyses were conducted to assess the impact of implant failure rates, implant cost markups, and OR time savings.
RESULTS
The 20-year cost of noncemented TKA ($20,829) was slightly higher than cemented TKA ($20,573). However, key variables markedly influenced cost-effectiveness. When the noncemented failure hazard ratio was reduced to 0.8, a cost savings of $1,676 was observed. Conversely, a hazard ratio of 1.2 led to a $1,768 increase in cost. A cost-neutral threshold was achieved with a 19% noncemented implant markup or 13 minutes of OR time saved. Additional savings were observed when OR time costs exceeded $54 per minute. Other variables, such as cement cost and patient age, had minimal impact.
CONCLUSION
Cementless TKA can be cost-neutral or cost saving over 20 years if specific conditions such as implant pricing and reduced OR time are met. Although clinical outcomes appear comparable between implant types, careful consideration of cost drivers and institutional practices is necessary. Noncemented TKA may be a viable, cost-effective option in selected patient populations, although further research is needed to refine these thresholds and evaluate long-term outcomes.