What Causes Knee Pain After Knee Replacement and Why Is It So Common?
On this page:
- Incidence of chronic knee pain after surgery
- Additional studies on knee pain after knee replacement
- Why your knee might not be the cause of your knee pain
The main reason you might make the drastic decision to undergo a knee replacement is to relieve your chronic knee pain, but did you know that many patients still have chronic pain after knee replacement surgery? Maybe you believe that a knee replacement is your only option. You’ve tried everything else, and now you just want to eliminate your pain once and for all. But is that a sure thing? Not even close.
The truth is, we’ve shared many studies over the years that show you shouldn’t count on a knee replacement to relieve your knee pain, and now there’s yet another study to add to the mounting list.
Incidence of Chronic Knee Pain After Surgery
A recent study looked at the percentage of patients with chronic knee pain after knee replacement at a minimum of one year following surgery in 272 patients (1). A questionnaire was sent to them at between 12 and 16 months following their surgery.
Of the 272 patients who responded, 107 patients (nearly 40%) reported that they still had persistent pain at one-plus year following surgery. The median average pain rating (using the 0-10 numeric pain scale) was 3 out of 10, with pain reported as high as 5 out of 10!
While you might think 5 out of 10, which is moderate pain, would be an improvement in knee pain after knee replacement, it isn’t that much different from the pain level most patients would describe prior to undergoing the knee replacement. Some studies have shown pain rates and percentages following knee replacements even higher at two, three, or four years following surgery, which seems to imply a trend toward pain worsening as time goes on, not getting better (2).
Even if your pain is 6, 7, 8 or more, do you really want to have your knee amputated for a possible 3, 4, or 5 pain rating? Or in the case of younger, more active patients, a whopping 15% of knee replacements are only lasting five years (3)! Five years! Wouldn’t you expect to get at least as many years out of your knee replacement as you’d get out of your Chevy?Learn about Regenexx procedures for knee conditions.
Additional Studies on Knee Pain After Knee Replacement
While this most recent study we highlighted shows nearly 40% of patients still having chronic knee pain after knee replacement, there are other studies reporting higher percentages.
This French study looked at almost 2,000 knee replacement patients one year after their surgery (4). They used a nationalized health care system to track the new use of over-the-counter pain medicine, nerve-pain drugs, and narcotics.
While we would expect to see very little new use of pain medications in this group of patients, a very surprising 47% of patients began taking new analgesic medications (like Tylenol and Motrin) during the year after their surgery! About 9% needed new nerve drugs and about 6% new narcotic drugs. Younger knee replacement patients and those with more pain before the surgery needed more drugs.
This study looked at more than 1,700 patients who had knee replacement (5). The focus was to determine how many would still have pain coming from the front of the knee joint. The researchers found that at five-plus years later, 20% had pain in the front of the knee.
However, a stunning 54% of patients still had knee pain with only 46% being pain free. Also interesting was that 87% of patients had their knee pain develop after the surgery and within the first five years. In addition, knee pain in the front was more common among younger and more active patients.
This study reported 44% of patients with chronic knee pain after knee replacement and a remarkable 15% with “severe-extreme persistent pain” (6).
Why Your Knee Might Not Be the Cause of Your Knee Pain
The frightening thing is that your knee may not be the actual cause of your knee pain at all. Multiple things in the spine and around the knee can cause knee pain. For example, the upper low back nerves, the sacroiliac joint, the muscles, and the tendons can all cause knee pain.
Why is this important? Well, why would you want to have a knee replacement if the knee isn’t the true cause of your pain? Perhaps this is the reason the pain doesn’t subside after surgery in such a high percentage of patients.
How is it possible that an arthritic knee isn’t the cause of knee pain? Many studies have shown that knee arthritis doesn’t necessarily cause pain. For example, many patients with arthritis on X ray and MRI have no knee pain!
A recent study decided to use the ultimate test in patients with knee pain to see if they actually had painful knee joints (7). They injected numbing medicine inside the knee joint to see if the knee pain went away. The results? About one-third of patients didn’t get any relief! Since it’s common for a knee replacement decision to be made with just a cursory exam and an X ray, if one-third of the patients with the most common form of arthritis don’t have pain coming from the joint, how many patients are getting unnecessary knee replacements?
The upshot? While different studies may theorize a variety of reasons for chronic pain after knee replacement, the fact is, studies show that knee pain remains in a very high percentage of patients. With 40% or more of patients still experiencing pain a year following total knee replacement (and pain percentages increasing even more over time), it is clear that chronic knee replacement pain is very common.
While it is possible you could be in the pain-free percentage, is it worth a knee amputation to find out? Especially when there are alternative options, such as stem cell injections, that may be able to relieve your pain without cutting out your knee? And even if a surgeon could guarantee that you would be pain-free following surgery, which he or she cannot, why go through a drastic, invasive knee replacement when there may be a nonsurgical solution?
Can a stem cell procedure help me? To find out if you might be a candidate for a Regenexx stem cell procedure, complete our Regenexx Procedure Candidate Form online.
(1) Sakellariou VI, Poultsides LA, Ma Y, Bae J, Liu S, Sculco TP. Risk Assessment for Chronic Pain and Patient Satisfaction After Total Knee Arthroplasty. Orthopedics. 2016;39(1):55-62. doi:10.3928/01477447-20151228-06
(2) Wylde V, Hewlett S, Learmonth ID, Dieppe P. Persistent pain after joint replacement: prevalence, sensory qualities, and postoperative determinants. Pain. 2011;152(3):566-572. doi:10.1016/j.pain.2010.11.023
(4) Fuzier R, Serres I, Bourrel R, Palmaro A, Montastruc JL, Lapeyre-Mestre M. Analgesic drug consumption increases after knee arthroplasty: a pharmacoepidemiological study investigating postoperative pain. Pain. 2014;155(7):1339-1345. doi:10.1016/j.pain.2014.04.010
(5) Metsna V, Vorobjov S, Märtson A. Prevalence of anterior knee pain among patients following total knee arthroplasty with nonreplaced patella: a retrospective study of 1778 knees. Medicina (Kaunas). 2014;50(2):82-86. doi:10.1016/j.medici.2014.06.001
(6) Wylde V, Hewlett S, Learmonth ID, Dieppe P. Persistent pain after joint replacement: prevalence, sensory qualities, and postoperative determinants. Pain. 2011;152(3):566-572. doi:10.1016/j.pain.2010.11.023
(7) Ikeuchi M, Izumi M, Aso K, Sugimura N, Tani T. Clinical characteristics of pain originating from intra-articular structures of the knee joint in patients with medial knee osteoarthritis. Springerplus. 2013;2:628. Published 2013 Nov 23. doi:10.1186/2193-1801-2-628