That Second Knee Replacement Could Be a Problem…

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The problem of a younger person getting a knee replacement has always been, what happens when the surgery needs to be redone? Meaning that most honest surgeons try to steer their patients to get a knee replacement surgery when they are as old as possible. Now new research adds weight to that decision-making process. Let’s dig in.

Do Knee Replacements Work in Younger People?

Back in 2017, researchers used the US government’s Osteoarthritis Initiative (OAI) dataset to look at the impact of age and activity on knee replacement outcomes (1). This was a critical study because it used data collected by disinterested researchers and not surgeons working on the behalf of knee replacement device companies. What did they find? Older and less functional patients did better with knee replacement, hence, in that age/activity group the procedure was cost-effective. The problem came when they looked at younger and more active patients, who were, in general, less likely to be satisfied and where it was more likely that the procedure wasn’t cost-effective.

If you’re interested in learning about knee replacement outcomes in general, here’s a video reviewing research showing lackluster results from the first surgery:

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Expanding Markets Despite the Evidence

Knee replacement device companies have a problem. While there is a slow market expansion year over year as the last of the baby boomers shift into retirement age, if you want to really blow out the size of your market, you must start to offer your product to younger and younger people. In fact, that’s exactly what these companies have done (2). Younger and younger patients and those who likely shouldn’t be getting knee replacements have been pushed to get the surgery and this is reducing the outcomes of the procedure (3,4).

The Second Knee Replacement Surgery

All of this also brings up a critical issue, when young people get a knee replacement, what happens when they need a second procedure? As a physician, I know that while the first surgery may take 60-90 minutes, the second knee replacement is a 2-4 hour affair. Why? Parts of your body have grown into the prosthesis and all of that has to be carefully dissected out so that complications like serious nerve or blood vessel injury don’t happen.

We also know that the size of the bone tunnels must be expanded. Meaning that the new prosthesis needs fresh bone to latch onto, so the doctor has to ream out the existing tunnels and make them bigger.

Other Issues with the Second Surgery?

A recent study on more than ten thousand patients found that almost half (47%) of patients undergoing a second knee replacement had complications (4). A third of patients were dissatisfied with their results. The authors concluded:

“…there was a high frequency of patient-reported complications. These findings may enable better informed discussion of the risks and benefits of discretionary rTKA.”

Meaning, avoid this second surgery if at all possible.

This is not the only paper to look at how much second knee replacement surgeries cost society (5). Prior authors have concluded that not only does the second knee replacement work poorly, but it also costs us all a huge amount of money.

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What Is Early?

Given that for an active person, we can expect a knee replacement prosthesis to last 15-20 years, then anyone who is younger than 65-70 when they get the first surgery is an early knee replacement. If you don’t plan on being active, then you may get 20-25 years out of a modern knee prosthesis. Hence, your mantra should be “one and done”.

How to Avoid an Early Knee Replacement?

There are three randomized controlled trials showing how best to avoid an early knee replacement (7-9). One published by our group and two by Herigou in France. All three use the patient’s own bone marrow concentrate. Looking at this data, you have a 4 in 5 chance of not needing an early knee replacement at 15 years after the procedure if you pursue these much less invasive bone marrow concentrate injection that contains your own stem cells.

The upshot? Early knee replacement is a big problem. You want that procedure to be “one and done”. Hence, do your homework on non-surgical options to avoid needing a second knee replacement procedure,



(1) Ferket BS, Feldman Z, Zhou J, Oei EH, Bierma-Zeinstra SM, Mazumdar M. Impact of total knee replacement practice: cost effectiveness analysis of data from the Osteoarthritis Initiative. BMJ. 2017 Mar 28;356:j1131. doi: 10.1136/bmj.j1131. PMID: 28351833; PMCID: PMC6284324.

(2) Singh JA, Lewallen DG. Time trends in the characteristics of patients undergoing primary total knee arthroplasty. Arthritis Care Res (Hoboken). 2014;66(6):897-906. doi:10.1002/acr.22233

(3) Singh JA, Lewallen DG. Are outcomes after total knee arthroplasty worsening over time? A time-trends study of activity limitation and pain outcomes. BMC Musculoskelet Disord. 2014 Dec 17;15:440. doi: 10.1186/1471-2474-15-440. PMID: 25519240; PMCID: PMC4301928.

(4) Riddle DL, Jiranek WA, Hayes CW. Use of a validated algorithm to judge the appropriateness of total knee arthroplasty in the United States: a multicenter longitudinal cohort study. Arthritis Rheumatol. 2014 Aug;66(8):2134-43. doi: 10.1002/art.38685. PMID: 24974958; PMCID: PMC4190177.

(5) Sabah S, et al. Patient reported function and quality of life following revision total knee arthroplasty: Analysis of 10,727 patients from the NHS PROMs programme. The Journal of Arhtroplasty. March 18, 2021 DOI:

(6) Bhandari M, Smith J, Miller LE, Block JE. Clinical and economic burden of revision knee arthroplasty. Clin Med Insights Arthritis Musculoskelet Disord. 2012;5:89-94. doi:10.4137/CMAMD.S10859

(7) Centeno C, Sheinkop M, Dodson E, Stemper I, Williams C, Hyzy M, Ichim T, Freeman M. A specific protocol of autologous bone marrow concentrate and platelet products versus exercise therapy for symptomatic knee osteoarthritis: a randomized controlled trial with 2 year follow-up. J Transl Med. 2018 Dec 13;16(1):355. doi: 10.1186/s12967-018-1736-8. PMID: 30545387; PMCID: PMC6293635.

(8) Hernigou P, Bouthors C, Bastard C, Flouzat Lachaniette CH, Rouard H, Dubory A. Subchondral bone or intra-articular injection of bone marrow concentrate mesenchymal stem cells in bilateral knee osteoarthritis: what better postpone knee arthroplasty at fifteen years? A randomized study. Int Orthop. 2020 Jul 2. doi: 10.1007/s00264-020-04687-7. Epub ahead of print. PMID: 32617651.

(9) Hernigou P, Delambre J, Quiennec S, Poignard A. Human bone marrow mesenchymal stem cell injection in subchondral lesions of knee osteoarthritis: a prospective randomized study versus contralateral arthroplasty at a mean fifteen year follow-up. Int Orthop. 2020 Apr 23. doi: 10.1007/s00264-020-04571-4. Epub ahead of print. PMID: 32322943.

Chris Centeno, MD is a specialist in regenerative medicine and the new field of Interventional Orthopedics. Centeno pioneered orthopedic stem cell procedures in 2005 and is responsible for a large amount of the published research on stem cell use for orthopedic applications. View Profile

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NOTE: This blog post provides general information to help the reader better understand regenerative medicine, musculoskeletal health, and related subjects. All content provided in this blog, website, or any linked materials, including text, graphics, images, patient profiles, outcomes, and information, are not intended and should not be considered or used as a substitute for medical advice, diagnosis, or treatment. Please always consult with a professional and certified healthcare provider to discuss if a treatment is right for you.

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