Panelists such as Michael A. Mont, MD, FAAOS, (left) and Julius Kunle Oni, MD, FAAOS, explored how the landscape of cementless total knee arthroplasty has evolved over the past few decades.
Published 10/19/2025
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Josh Baxt
Cementless total knee arthroplasty (TKA) had a rough start. Early designs in the 1990s had poor osteoconductive surfaces and inadequate fixation devices. A 1991 study showed that the six-year survival for these implants was 77%, and a 2001 study showed that after 11 years, survivorship was only 52%. Problems such as loosening tibial components and failure of bone ingrowth were significant and widespread with cementless TKA. Cement was much more forgiving, and antibiotic cement was often favored for patients who might be at a higher risk for infection.
Now the landscape has changed. “100% of the knees I perform are cementless,” said Michael A. Mont, MD, FAAOS, during the Instructional Course Lecture titled “Cementless total knee arthroplasty on the rise in the United States: why and what do we know?” held at the AAOS 2025 Annual Meeting. He was joined by Adolph V. Lombardi Jr., MD, FAAOS; Julius Kunle Oni, MD, FAAOS; and Antonia F. Chen, MD, MBA, FAAOS.
Dr. Mont, an orthopaedic surgeon at Sinai Hospital of Baltimore, discussed a variety of advances in cementless device designs, including more bone-friendly compositions, enhanced tibial fixation, and improved surface coatings. As a result, efficacy has shot up, with a 2014 study he led putting 10-year survivorship at 95.6%.
“Cemented used to be the gold standard, but I don’t think that’s true anymore,” Dr. Mont said. “The facts have changed.”
Why switch?
To some degree, implants are changing because patients are changing. Dr. Lombardi, who is president of JIS Orthopedics in Albany, Ohio, noted that patients were often sedentary when he started practicing in 1987. They are far more active today.
In addition, cement degrades over time. “When you implant cement, it is the best the day you put it in,” he explained. By contrast, the cementless interface should get better over time as it integrates with bone. Cemented results are highly dependent on the implant, cement, and surgical technique.
Dr. Lombardi shared a review of the literature, explaining there are no differences between cemented and cementless results in young patients and increased survivorship in obese patients.
“Younger, heavier, more active patients are at higher risk of total loosening in the cemented designs,” he said. “The modern generation [of] cementless has the potential to provide long-term biological fixation.”
Surgical techniques
Dr. Chen, who is the Dr. Charles F. Gregory Distinguished Chair in Orthopaedic Surgery at UT Southwestern Medical Center, discussed some of the surgical nuances associated with cementless TKA. She shared her initial reluctance to switch to cementless, as the patch porous coating did not achieve initial press-fit fixation to accommodate bony ingrowth due to implant liftoff, subsidence, and progressive loosening. There were also issues with femur fixation, as well as problematic polyethylene.
As the technology improved and uptake increased, Dr. Chen gradually came around to consider cementless implants. She saw the potential for bone integration in the new designs to reduce micromotion. In addition, robotic technologies support perfect cuts, alleviating the need for cement. Removing cement from the equation also reduces cost and time and avoids the potential for cement debris.
“You start with your young, healthy, active individuals with a lot of good bone,” Dr. Chen said. “Typically, you start with males, especially for younger and more active patients who seem to make more biologic sense.”
She also found that cementless implants can work well for patients older than 75 years, provided they have good bone quality. She stressed the importance of assessing bone quality and making perfect cuts to avoid micromotion.
On the cost front, Dr. Chen noted that, on average, cementless TKA is less expensive, costing about $8,000 compared with more than $8,500 for cemented TKA. Although the literature shows that cementless TKAs have improved survivorship, she acknowledged the need for long-term studies.
Dr. Oni, who practices at Johns Hopkins Medicine, had a similar experience as Dr. Chen, starting in younger, active patients. Now about 80% of TKAs he performs are cementless. Like the other surgeons, he saw that the issues plaguing early cementless implants, such as femoral component fractures and severe osteolysis, were resolved with better designs.
On the procedural side, he also made a few recommendations. “When you cut in the tibia, ideally, you would want to cut just once,” Dr. Oni said. “You don’t want to cut multiple times because you increase the risk of an uneven cut. And whenever you cut, particularly on sclerotic surfaces, and you see smoke, you probably want to irrigate so that you don’t cause any thermal necrosis.”
To some degree, the choice between cemented and cementless hinges on bone quality. Dr. Oni believes that dual-energy x-ray absorptiometry scans do not accurately capture knee biology. For him, the true test comes intraoperatively.
“If you’re sawing through that bone and it’s just like butter, then you probably want to consider doing a cemented knee,” he said.
To close, Dr. Mont returned to the stage to discuss the evidence. A comprehensive literature search showed that in 27 randomized, controlled trials, cementless survivorship ranged from 93.7% to 100%. The range for cemented implants, at the same mean follow-up, was 90% to 100%. Several long-term studies showed cementless survivorship greater than 98%.
Regarding the promising outcomes of cementless TKA, Dr. Mont said, “It’s not just survivorship.” In terms of clinical scores and function, as well, he emphasized, “The patients are doing well.”
Josh Baxt is a freelance writer for AAOS Now.
References
- Moran CG, Pinder IM, Lees TA, Midwinter MJ. Survivorship analysis of the uncemented porous-coated anatomic knee replacement. J Bone Joint Surg Am. 1991;73(6):848-857.
- Berger RA, Lyon JH, Jacobs JJ, et al. Problems with cementless total knee arthroplasty at 11 years follow-up. Clin Orthop Relat Res. 2001;(392):196-207. doi:10.1097/00003086-200111000-00024
- Mont MA, Pivec R, Issa K, Kapadia BH, Maheshwari A, Harwin SF. Long-term implant survivorship of cementless total knee arthroplasty: A systematic review of the literature and meta-analysis. J Knee Surg. 2014;27(5):369-376. doi:10.1055/s-0033-1361952
- Lawrie CM, Schwabe M, Pierce A, Nunley RM, Barrack RL. The cost of implanting a cemented versus cementless total knee arthroplasty. Bone Joint J. 2019;101-B(7_Supple_C):61-63. doi:10.1302/0301-620X.101B7.BJJ-2018-1470.R1
- Franceschetti E, Torre G, Palumbo A, et al. No difference between cemented and cementless total knee arthroplasty in young patients: a review of the evidence. Knee Surg Sports Traumatol Arthrosc. 2017;25(6):1749-1756. doi:10.1007/s00167-017-4519-5
- Sinicrope BJ, Feher AW, Bhimani SJ, et al. Increased survivorship of cementless versus cemented TKA in the morbidly obese. A minimum 5-year follow-up. J Arthroplasty. 2019;34(2):309-314. doi:10.1016/j.arth.2018.10.016