Manage the pain, then replace the knee.
In a Medicare sample of 275,256 people with knee osteoarthritis, joint replacement took 51% of the spending, though only 12.9% had one. Physical therapy took 3.8%.
Most people meet knee osteoarthritis in the same way. A knee that aches on the stairs, then on the walk to the shops, then at night. An appointment, perhaps an X-ray, a prescription for painkillers. Later an injection, sometimes a few sessions of physiotherapy. And somewhere at the end, often years away, a conversation with a surgeon about a new knee.
Clinicians call this a stepped approach, and on paper it is sensible: start with the least invasive option and climb only when you must. But look at where the money and the attention go, and the ladder turns out to be strangely built. The bottom rungs, the ones meant to carry people for years, are thin. The top rung is heavy.
Where the money goes
In 2020, Gerard Malanga and colleagues published an analysis of a 5% sample of Medicare claims in the United States. They identified 275,256 people with knee osteoarthritis and tracked their knee-related claims from 2010 to 2015.1 Over that period, costs related to knee osteoarthritis came to $1.196 billion.
Knee arthroplasty, the replacement operation, accounted for 51% of that total. Yet only 35,465 of those patients, 12.9%, had a replacement during the study.1 Office visits took 14.6% of the money, drawing fluid from the joint 8.7%, hyaluronic acid injections 5.6%, imaging 4% and corticosteroid injections 3.6%. Physical therapy took 3.8%.
Where knee osteoarthritis spending went
Share of knee OA related costs, 5% Medicare sample, 275,256 patients, 2010 to 2015 (prescription drugs not included)
Source: Malanga et al., American Health & Drug Benefits (2020)
The authors could not include the cost of prescription drugs, so the picture is incomplete.1 But its shape is clear. Roughly one patient in eight had the procedure that accounted for half the money. Everything else, for everyone living with the condition through the long middle, came out of the other half, and physical therapy, one of the main ways people are taught the exercise that guidelines put first, was among its smallest lines.
What the guidelines put first
On the foundations of treatment, the major guidelines agree. The National Institute for Health and Care Excellence (NICE) in England states that “the core treatments for the condition are therapeutic exercise and weight management (if appropriate)”.2 The 2019 guideline from the American College of Rheumatology and the Arthritis Foundation makes strong recommendations for exercise, for weight loss in people with knee or hip osteoarthritis who are overweight or obese, and for self-efficacy and self-management programmes.3
They are just as clear about what to leave out. NICE advises that osteoarthritis can be diagnosed clinically, without imaging, in people with the typical picture. It says plainly: “Do not offer intra-articular hyaluronan injections to manage osteoarthritis.” It also advises against strong opioids and against arthroscopic lavage or debridement.2 The American guideline conditionally recommends against hyaluronic acid injections in the knee and against opioids other than tramadol.3
What actually happens
Practice looks different. In Australia, Kim Bennell and colleagues analysed a nationwide survey of general practice. Between 2010 and 2016, GPs recorded 74.3 medications for every 100 knee osteoarthritis problems they managed, including 14.9 opioids. Against that, they recorded 5.0 referrals to a physiotherapist and 0.2 to an exercise physiologist.4 The use of MRI for knee osteoarthritis rose fivefold compared with 2005 to 2010. The authors concluded that strategies are needed to “optimise lifestyle management and reduce low-value care”.4
In the United States, a study in The Journal of Bone and Joint Surgery looked at insurance claims for 24,492 commercially insured people, average age 60, in the year before a knee replacement carried out in 2018 or 2019.5 More than half, 54.3%, had corticosteroid injections into the knee. According to the journal publisher’s summary of the study, about 13% had hyaluronic acid injections, which alone made up 10% of the cost of nonoperative care, and about 27% had physical therapy.5
These are people at the very top of the ladder. The data cover only the final year, so some will have had therapy earlier. Still, in the twelve months before surgery, fewer than three in ten had physical therapy, while more than half had a steroid injection.
A system, not a profession
None of this is a story about careless clinicians. Most doctors and physiotherapists know the guidelines well, and many spend their working lives trying to keep patients moving. The difficulty is structural. Health systems tend to pay most readily for things that can be done to a knee in a single visit: a scan, an injection, an operation. Months of exercise, weight management and patient education are harder to deliver, harder to follow up and easier to drop when appointments are short.
The result is a ladder upside down. The years in which a person could build strength, learn to manage flares and keep walking are the years the system funds least. The operation at the end, valuable as it is for many people, is where the money gathers. And in the Medicare sample, almost nine in ten people with knee osteoarthritis did not reach that end during the study period. They lived in the middle. (We have written about how long that middle can last and about the muscles that carry a knee through it.)
Rebuilding the middle
Turning the ladder the right way up does not mean taking anything away from surgery. It means treating the long stretch before it as care in its own right, with exercise, education and weight management delivered early, supported over time and measured as carefully as any procedure. The guidelines already say so. The spending has not caught up. (What Medicare covers in those years, and what households pay themselves, is the subject of a companion piece.)
At Veema we work on the middle years: on standing up, walking and staying at home while living with a stiff, painful knee. Whether a wearable device can help people through that stretch is a question only careful studies with older adults can answer. What the numbers already show is how little the current system spends there.
These figures describe the need. They are not results or claims about Veema.
Sources
- Malanga et al., American Health & Drug Benefits (2020): 5% Medicare sample, 275,256 knee OA patients, 2010 to 2015; $1.196 billion knee OA related costs; 35,465 (12.9%) had arthroplasty; cost shares: arthroplasty 51%, office visits 14.6%, arthrocentesis 8.7%, hyaluronic acid 5.6%, imaging 4%, physical therapy 3.8%, corticosteroid injections 3.6%; drug costs not examined.
- NICE guideline NG226, Osteoarthritis in over 16s (2022): Recommendations 1.1.1 (clinical diagnosis without imaging), 1.2.2 (core treatments are therapeutic exercise and weight management), 1.4.6 (no strong opioids), 1.4.9 (no intra-articular hyaluronan), 1.7.1 (no arthroscopic lavage or debridement).
- Kolasinski et al., Arthritis & Rheumatology (2020), DOI 10.1002/art.41142: 2019 ACR/Arthritis Foundation guideline: strong recommendations for exercise, weight loss in overweight or obese knee/hip OA, self-efficacy and self-management programmes; conditional against intra-articular hyaluronic acid in knee OA and against non-tramadol opioids.
- Bennell et al., The Lancet Regional Health Western Pacific (2021), DOI 10.1016/j.lanwpc.2021.100187: Australian general practice, 2010 to 2016, per 100 knee OA problems: medications 74.3, opioids 14.9, physiotherapist referral 5.0, exercise physiologist referral 0.2; knee MRI use rose 5-fold versus 2005 to 2010; quote on low-value care.
- Nin et al., The Journal of Bone and Joint Surgery (2022), DOI 10.2106/JBJS.21.01415: 24,492 commercially insured TKA patients (MarketScan, mean age 60.4), 2018 to 2019, year before surgery: corticosteroid injections 54.3% (abstract); hyaluronic acid about 13% of patients and 10% of nonoperative costs, physical therapy about 27% (publisher press release, wolterskluwer.com, not in the abstract).
