Ross Hauser, MD., Danielle R. Steilen-Matias, MMS, PA-C
Finding help for post knee replacement pain
Can we help you with your continued knee pain after knee replacement surgery? In this article we will explore the problems identifying the source of knee pain after knee replacement and how identifying and treating soft tissue damage may be the answer to pain after knee replacement.
Many of the patients that we see with knee pain after knee replacement have pain on the outside of the knee. This is where the ligaments and the tendons are. Most often these connective tissues are damaged either by the surgery or new stress placed on them by the implant. This can be the cause of why a knee wobbles, is unstable and has become hypermobile. This unsteadiness and hypermobility pulls and tugs at the ligaments and tendons which causes the patient a lot of pain. Some patients have nerve irritations. This nerve irritation can be below or above the knee or along with the kneecap. We would treat these problems with nerve release therapy.
Many people have excellent results with their knee surgery. These are typically not the people we see in our office. We see the people who still have pain, non-hardware-related knee instability, and pain in the other knee from over-compensation among other challenges. Some of these people were told that their surgery was a complete success, as far as the actual surgery goes. But as we hear in these patient stories. The surgery came up short in expectation.
Everything is normal I guess, except for my pain, knee instability, and the explained noises my knee is making.
This is something we typically hear in a post-knee replacement patient who is having some challenges.
I started to become concerned when I noticed a clunking and clicking sound coming from my knee.
I put off the knee replacement as long as I could. This was not a decision I wanted to take lightly but my knee was in constant pain, my doctor told me I really had no other choice. So I had surgery on one knee. My doctor was very pleased with the surgery. Said everything went well, the rest was up to me. I need to do physical therapy, I needed people at home to help me, I was going to be very dependent. Lucky for me, I had everything I needed to ensure a good recovery.
I started to become concerned when I noticed a clunking and clicking sound coming from my knee. Like metal on metal. My doctor told me that this was no concern, some people who get knee replacements have these “old car,” sounds coming from their knee. Not to worry. My doctor did advise me that the sounds if they continued could be caused by weakened muscles and tendons in my knees and I should consider an exercise program to tighten them up.
I did ask if the knee implant was coming loose. My doctor said, if it were, I would not be able to walk up and down stairs or even put weight on that foot. I would have a lot of swelling and I would feel like my knee may give out. I looked at the doctor and said, BUT I DO HAVE THOSE SYMPTOMS, “Yes you do,” the doctor said, but it is not from implant loosening. You probably just need to strengthen that knee up.
In this article we will examine problems such as those we illustrated above in addition to discussing:
A large number of people are affected by chronic pain after total knee replacement
Doctors are looking for the causes of pain after knee replacement and it is hard to find
One in four patients with pain after knee replacement had no clear reasoning for their pain
It looked like neuropathy but it wasn’t neuropathy.
Mystery pain, unclear pain, difficult to treat pain after knee replacement.
Post knee replacement health problems are a bigger problem than anticipated. The patient problems after knee replacement surgery are many.
After the surgery, the researchers found patients had to alter their recovery and post-surgery strategy to account for new health problems and problems of mobility.
Research: 10% to 34% of patients are not satisfied with a knee replacement.
Studies have demonstrated that poor management of acute pain after total knee replacement is strongly associated with the development of chronic pain.
Patients had knee pain after a knee replacement because, after the fact, it was determined that knee replacement was the wrong surgery.
Radiofrequency ablation of genicular nerves.
Problem: Neuropathic knee pain after surgery – nerve damage caused by the surgery.
Why physical therapy failed.
Neuromuscular electrical stimulation.
Possible solution: Post-surgical pain and knee instability may be from the surviving ligaments.
Can physical therapy help post-total knee replacement pain?
Adverse knee pain occurs in 10-34% of all total knee replacements, and 20% of total knee replacements patients experience more pain post-operatively than pre-operatively.
A September 2020 study from Newcastle University in the United Kingdom (1) explains the likelihood of pain after knee replacement and what may cause it. Further in this article, we will explore some of these reasons for post-knee replacement pain. Here are the highlights of this research:
Adverse knee pain occurs in 10-34% of all total knee replacements, and 20% of total knee replacements patients experience more pain post-operatively than pre-operatively.
Arthrofibrosis (excessive scar tissue),
Central sensitization, (over sensitization to pain. Sometimes patients are told that they have more pain than they should).
Component malpositioning, (the replacement is in wrong).
Instability, (what we will discuss below is not just instability from the hardware loosening, but the instability of the knee itself causing pain in the soft tissue of the knee).
Overstuffing, (your knee joint is bigger after the knee replacement and this is causing a sensation of your knee being “overstuffed,” “too fill.”
Patellar maltracking, (the knee cap is not in the right place or moving correctly)
A large number of people are affected by chronic pain after total knee replacement
“Despite a good outcome for many patients, approximately 20% of patients experience chronic pain after total knee (replacement) arthroplasty.”
When we discuss the problems of joint replacement, we always bring in the joint replacement specialists for their opinion. This is a recent research sampling of doctors who specialize in knee replacement.
In the medical journal EFORT Open Reviews, (2) published by the British Editorial Society of Bone & Joint Surgery, doctors wrote in August 2018:
“Despite a good outcome for many patients, approximately 20% of patients experience chronic pain after total knee (replacement) arthroplasty.”
Chronic pain after total knee replacement can affect all dimensions of health-related quality of life, and is associated with:
poorer general health,
and social isolation.
Comment: The very reasons many consider having knee replacement surgery
Assessment of the cause of pain after total knee replacement has been inadequate
Finally: “Treatment of chronic pain after total knee replacement is challenging, and evaluation of combined treatments and individually targeted treatments matched to patient characteristics is advocated.”
An April 2022 paper (42) from researchers at Oxford University and the University of Bristol in the the United Kingdom found that chronic pain was reported in 70/552 operated knees (12.7%) one year after the knee replacement surgery. Those patients within the chronic pain group had worse pain, function and health related quality of life pre-surgery and post-surgery than the non-chronic pain group. Those without chronic pain markedly improved right after surgery, then plateaued.
Lack of evidence about the effectiveness of prediction and management strategies for chronic postsurgical pain after total knee replacement
The same doctors also wrote in the British Medical Journal(3) that the problem of post-surgical pain in knee replacement patients had reached a point of significance and that researchers should prioritize their studies to help people with pain. They wrote:
“Our (study) highlights a lack of evidence about the effectiveness of prediction and management strategies for chronic postsurgical pain after total knee replacement. As a large number of people are affected by chronic pain after total knee replacement, development of an evidence base about care for these patients should be a research priority.”We are going to return to this study below.
There is a significant problem. The main part of this problem is identifying what is causing people to have pain after knee replacement.
Research: Doctors are looking for the causes of pain after knee replacement and it is hard to find
The confusion as to what may be the cause of chronic knee pain after knee replacement is a cause of great concern not only among doctors but obviously among patients. We often find patients to be confused between what is normal and what is not normal after knee replacement.
Is some pain normal?
Are the clunking sounds normal?
Is the instability normal?
Painful knee after total knee arthroplasty – what can be done? Find a diagnosis
Diagnosis of what is causing knee pain after a knee replacement is hard to find. The first thing to look for is some type of hardware failure or pain caused by the surgery itself. You knee a knee surgeon to help with that.
In December 2020, doctors in Germany offered the suggestion that you need a surgical specialist in fixing a bad knee replacement to start the process of understanding why the knee replacement failed. (4)
“About one-third of all patients after total knee arthroplasty experience persistent or recurring pain and/or dissatisfaction. Clinically, the symptoms are very complex and vary greatly from individual to individual. Diagnostic clarification is difficult and should be carried out by an orthopedic surgeon specializing in knee arthroplasty revisions. Only if the cause(s) of the complaints are identified is there a chance of improvement, regardless of whether conservative or surgical treatment is used.”
Establishing a precise diagnosis of where the pain is coming from can be challenging.
Researchers at the Department of Surgery, Southern Illinois University School of Medicine offered this assessment in the medical information publication Instructional Course Lectures(5) to guide doctors trying to help patients with pain after knee replacement.
Establishing a precise diagnosis of where the pain is coming from can be challenging.
According to the research: This is what doctors need to look for in trying to find the source of knee pain after knee replacement:
Pain after knee replacement can be classified as intra-articular (from within the knee) or extra-articular pain (from sources outside the knee).
After intra-articular causes (described below), such as knee instability, aseptic loosening (a loose knee replacement), infection, or osteolysis (loss of bone), has been ruled out, extra-articular sources of pain should be considered.
Extra-articular sources of pain can be found after a physical examination of the other joints which may reveal sources of localized knee pain, including diseases of the spine, hip, foot, and ankle.
(STOP HERE: Let’s stop for a moment. After the knee replacement, you still have knee pain. The doctors in this study are saying to examine the spine, the hips, the ankles, the feet, these joints may be causing the knee pain problem. What if these joints were the cause of knee pain in the first place? See below, was knee replacement the wrong surgery?)
MORE: Additional extra-articular pathologies (pain from degenerative disorders from outside the knee) that have the potential to instigate pain after total knee replacement include cardiovascular problems, tendinitis, bursitis, and iliotibial band friction syndrome.
A 2019 paper from Brigham and Women’s Hospital, Harvard Medical School, Boston (34) describes the problems of opioid use before knee replacement.
“Prescription opioid use is common among patients with moderate to severe knee osteoarthritis before undergoing total knee replacement. Preoperative opioid use may be associated with worse clinical and safety outcomes after total knee replacement.”
In this study, the researchers targeted preoperative opioid use among patients 65 years and older with mortality and other complications at 30 days post-total knee replacement.
Study learning points:
316,593 patients (average age about 74 – 67.8% women) who underwent total knee replacement:
22,895 (7.2%) were continuous opioid users before surgery.
161,511 (51.0%) were intermittent opioid users before surgery.
132,187 (41.7%) did not use opioids before surgery.
At 30 days post- total knee replacement:
828 patients (0.26%) died,
16,786 patients (5.30%) had hospital readmission, and
921 patients (0.29%) had a revision operation.
All primary and secondary outcomes occurred more frequently among continuous opioid users compared with opioid-naive patients.
Compared with opioid-free patients the number of different prescription medications, and frailty, continuous opioid users had a greater risk of revision operations, vertebral fractures, and opioid overdose at 30 days post-total knee replacement.
These results highlight the need for a better understanding of patient characteristics associated with chronic opioid use to optimize preoperative assessment of overall risk after total knee replacement.
Is post-surgical knee pain coming from knee tendinopathy?
Is it tendonitis? In many patients we see, we find that the pain is coming from the outside of the knee. When the knee is replaced, the knee cartilage is now replaced with hard plastic, so lack of or loss of cartilage is not causing the pain. What can be causing the pain are the remaining tendons and ligaments that surround the outer portions of the knee? These tendons and ligaments have become weakened, they are loose and they are allowing for a wobbly knee situation. When the knee is wobbly, it is not moving correctly, it creates an unnatural and painful pull on these ligaments and tendons and this causes pain and instability. The strain on the knee tendons can cause chronic tendinopathy.
Can physical therapy help post-total knee replacement pain?
Research led by the Boston University School of Medicine published in October 2021 in the journal JAMA Network Open (32) examined the problem of patients who become long-term opioid users after undergoing a total knee replacement. The goal of this research was to see if physical therapy could help prevent opioid use. To do this the medical records of over 38 thousand people who did not use opioids and almost 29 thousand patients who did use opioids after knee replacement was assessed looking for those patients who had physical therapy either before knee replacement or after knee replacement or both or neither.
The researchers found that patients receiving physical therapy before and after total knee replacement, and had six or more sessions of physical therapy care after total knee replacement, and initiation of physical therapy care within 30 days after total knee replacement was associated with lower odds of long-term opioid use. These findings suggest that physical therapy may help reduce the risk of long-term opioid use after total knee replacement.
Radiofrequency ablation of genicular nerves
A November 2021 study from the University of New Mexico School of Medicine published in the medical journal Cureus (33) wrote:
“Painful total knee replacement without an obvious underlying identifiable pathology is not uncommon. Dissatisfaction after total knee replacement can be up to 20%. Different treatment modalities, including non-operative and operative procedures, have been described in (medical studies).
Radiofrequency ablation of genicular nerves is emerging as a newer treatment modality for painful total knee replacement without an obvious underlying identifiable pathology (diagnosis). Despite a modest number of publications demonstrating the usefulness of Radiofrequency ablation of genicular nerves in managing pain in knee osteoarthritis, the efficacy of Radiofrequency ablation of genicular nerves has not been completely established in the management of residual pain after total knee replacement.”
Here is a situation where people will have pain after knee replacement and the reason for their knee pain cannot be found. One answer for these people is to burn out their nerves. For some this can be successful for others as noted above, it may not be successful because the radiofrequency ablation did not find the underlying cause for the patient’s pain.
The problems of obesity
Let’s start with a March 2019 study (37) published in The Journal of arthroplasty. Here doctors and researchers examined the existing medical controversies surrounding joint replacement in obese and morbidly obese patients and whether or not a bariatric surgery before joint replacement would help. Over 38,000 patient case histories were reviewed. The researchers of this paper found medical comorbidities and com[plication were higher in the bariatric surgery group than a control morbid obesity group before total joint replacement.
There were short-term benefits in the bariatric surgery. The researchers observed that bariatric surgery prior to total joint replacement was associated with reduced short-term medical complications, length of stay, and operative time. However, “bariatric surgery did not reduce the short-term risks for superficial wound infection or venous thromboembolism, and the long-term risks for dislocation, periprosthetic infection, periprosthetic fracture, and revision.”
Complication of a second knee replacement in obese patients
A February 2022 study of 605,603 revision total knee arthroplasty surgeries published in the Journal of the American Academy of Orthopaedic Surgeons. Global research & reviews (38) examined the postoperative outcomes of obesity and morbid obesity patients after revision total knee arthroplasty. The researchers here found obese and morbidly obese patients were at significantly higher risk for complications than non-obese patients. “Morbidly obese patients had a significantly longer length of stay than both obese and not obese patients, while no significant difference in length of stay was observed between obese and not obese patients.”
Prolotherapy and Platelet Rich Plasma Therapy
We are going to briefly address two treatment options that we offer here at Caring Medical. We will explore these treatments more deeply below. These are non-surgical, injections. They are not cortisone, they are not gel shots.
Prolotherapy is an injection technique utilizing simple sugar or dextrose which causes a small controlled inflammation at weakened tissue. This triggers the immune system to initiate repair of the injured tendons and ligaments. Blood supply dramatically increases in the injured area. The body is alerted that healing needs to take place and reparative cells are sent to the treated area of the knee that needs healing. The body also lays down new collagen in the treated areas, thereby strengthening the weakened structures. Once the tendons and ligaments are strengthened, the joint stabilizes and the tendonitis or tendinosis condition resolves.
Platelet Rich Plasma Therapy is the use of a patient’s blood platelets and healing factors to stimulate repair of a tendon it is considered when tendon damage is more severe. We will be discussing these treatments further below and try to provide a realistic outlook as to if these treatments may benefit you.
Research: Surgeons warn surgeons that knee pain after knee replacement does not automatically mean REVISION KNEE SURGERY
One of the reasons that people are in our office with continued pain after knee replacement is that they are being told that eventually, or sooner, rather than later if the pain persists, they will have to have revision surgery to clean out tissue that may be causing pain, and to examine the components of the artificial knee.
A recent study from orthopedic surgeons in Italy was published in the Current Reviews in Musculoskeletal Medicine. (6) Simply stated the surgeons warned:
“Pain (after knee replacement) can be related to a lot of different clinical findings, and the surgeon has to be aware of the various etiologies that can lead to failure. Pain does not always mean revision, and the patient has to be fully evaluated to have a correct diagnosis; if surgery is performed for the wrong reason, this will surely lead to a failure.”
Will your bones even allow for a revision knee replacement?
An August 2019 study in the Journal of Orthopaedic Surgery and Research (7) offered this warning to surgeons concerning the problems of identifying whether a patient’s bones were strong and dense enough to withstand another knee replacement procedure.
“Revision total knee arthroplasty (replacement) is a demanding procedure, with a high complication and failure rate and a high rate of bone losses and poor bone quality. Different classifications for bone losses have been proposed, but they do not consider bone quality, which may affect implant fixation.
Look at the study findings:
Fifty-one patients (53 knees – 2 patients had both knees replaced) were included (about 3 out of 5 patients were women, average age 71.5 years).
The most frequent cause of failure was:
aseptic loosening of the implant (41.5%).
18.9% of the cases demonstrated poor bone quality.
What the researchers of this study were seeking to point out is that if revision knee replacement is required, a plan to address and repair the possibility of bone loss, bone weakening, a loss of bone density should be undertaken. This would significantly increase the success of the replacement.
Research: Many studies search for answers for “Mystery Pain” after Knee Replacement
Surgeons say one in four patients with pain after knee replacement had no clear reasoning for their pain. It wasn’t the hardware, it wasn’t anything obvious that they could see.
In the research above, surgeons have a road map of where to look for pain after knee replacement. Returning to the findings released in the British Pain Journal (3), the doctors suggest looking for pain in other places that are usually not explored:
Our main findings are that some patients have severe pain that interferes significantly with their lives and that a large number of them have pain sensitization problems (heightened sense of pain), many of which can be classified as neuropathic pain (nerve damage or pain), rather than any local, nociceptive cause (pain caused by the surgical procedure).
A heightened sense of pain following knee replacement will be discussed throughout this article.
However, it was not possible to categorize all patients as having either a local cause for their pain (the site of the surgery and surrounding affected tissues) or a pain sensitization problem, as many had complex unclassifiable causes for the pain, including psychosocial problems.
What is the research saying?
Only a small percentage of patients at 2 years post-knee replacement have neuropathic (neuropathy) pain. It is
Excluded patients who had clear mechanical or other orthopedic problems, the doctors STILL found that 25% of the remainder had neuropathic-like pain, and many more had pain sensitization, contributing to the pain problem. It looked like neuropathy but it wasn’t neuropathy.
This is important, first, as many orthopedic surgeons are not familiar with how to detect these patients, and second, because there are simple therapies available to treat them.
Surgeons dealing with patients with significant and persistent knee pain following knee replacement should assess levels of neuropathic pain, pain at other sites, and depression.
In November 2018 a study was published in the Journal of Knee Surgery. (8) The doctors also were looking at nerve pain after surgery.
The study had 154 patients with 222 knee replacements (66 patients had both knees replaced)
The goal of the study was to define the prevalence of pain persisting after total knee replacement and determine the impact of neuropathic pain.
A significant number of patients experienced moderate-to-severe and unclear pain after total knee replacement.
It looked like neuropathy but it wasn’t neuropathy.
It looked like neuropathy but it wasn’t neuropathy. Mystery pain, unclear pain, difficult to treat pain after knee replacement. Post knee replacement health problems are a bigger problem than anticipated
One of the problems we see in patients who are having problems post-knee replacement surgery is the thinking that knee replacement works for everyone, how come it didn’t work for them?
When these patients are presented with research compiled from patient outcomes, they are somewhat surprised to see that they are not so unique after all, many patients have reported problems with expectations and complications of their knee replacement(s).
Knee replacement is considered one of the great innovations in musculoskeletal care. It is said to be the only known cure for knee osteoarthritis. Orthopedist surgeons routinely tell patients of the great success of the procedure. Yet, it was not until doctors started to perform outcome questionnaire studies that the medical community started to realize what patients had already known – knee surgery was not as successful as the surgeons thought.
What patients want from their knee replacement:
In the November 2017 edition of the journal Medical Care, (9) a combined research team from the University of Illinois at Chicago, China Medical University Hospital, and National Taiwan University Hospital published their findings on what concerned patients before knee replacement and the type of pre-existing conditions these patients had.
Before the surgery concerns about successful surgery circled around these factors:
The ability to take care of themselves immediately after the surgery.
The ability to move and have mobility after the surgery.
The ability to be able to perform their own usual activities,
The amount of pain and discomfort during recovery and post-op.
Research continued: After the surgery, the researchers found patients had to alter their recovery and post-surgery strategy to account for new health problems and problems of mobility
The amount of pain and discomfort in recovery and post-op became the greatest impact of post-surgical patient non-satisfaction.
Compared with preoperative health problems, postsurgical health problems were associated were a bigger problem than anticipated.
Significant differences in thinking before surgery and surgical outcomes were observed including
Greater problems than anticipated in:
Not being able to perform usual activities,
It is important to know that the purpose of this research was to assign a set of values to these patient problems in order to be able to come up with a formula that would better help the patient with their expectations before and after the surgery. The researchers had to conclude in the end that:
“Our systematic review highlights a lack of evidence about the effectiveness of prediction and management strategies for chronic postsurgical painafter total knee replacement.”
In the end, there is no way currently to predict who will benefit and who will get worse from knee replacement surgery and patients should be counseled that there is no guarantee that knee replacement will work for them.
Patients should be counseled that there is no guarantee that knee replacement will work for them
Research: 10% to 34% of patients are not satisfied with knee replacement
In August 2017, doctors at the University Hospital Leipzig in Germany opened their published research in the medical journal Patient Safety in Surgery(10) with this statement:
In spite of the improvement of many aspects around Total knee arthroplasty (total knee replacement), there is still a group of 10% to 34% of patients who are not satisfied with the outcome.
The therapy of chronic pain after total knee replacement remains a medical challenge that requires an interdisciplinary therapy concept. (In other words, more doctors, more providers, more treatments).
What this paper deals with is an ever-growing population of people for whom knee replacement did not work.
In their paper the Leipzig researchers were looking at effective means to help the patient with pain after knee replacement, a brief summary of their findings is presented here:
“The treatment of patients with chronic complaints after total knee replacement is a challenging task. Therefore, an adequate therapy is only possible due to an interdisciplinary team of experienced orthopaedic surgeons with great knowledge in the field of endoprosthetic (knowledge of hardware failure and misfit), qualified physiotherapists (patients with problems after knee replacement often suffer from the various stage of depression) and pain therapists.” (The patients are in pain, sometimes more so than before the surgery.)
The researchers then assessed the following of having some benefits:
Acupuncture or Traditional Chinese Medicine which assisted in reducing knee swelling in some patients
Gentile Physiotherapy (getting the patient to move to get circulation and reduce swelling and fluid collection in the knee).
Injections of bupivacaine and lidocaine for very temporary relief
Treatment should be supported by psychotherapists or psychologists with experiences in the area of psychosomatic medicine. (We will deal with depression and anxiety below)
The doctors concluded that following the guidelines presented, some patients could be shown to have pain improvement.
Harvard Medical School’s findings surrounding the phenomena of continued pain following total knee replacement
Here are some more quick facts surrounding the phenomena of continued pain following total knee replacement from researchers at Brigham and Women’s Hospital, Harvard Medical School.
In this 2017 study published in the medical journal Osteoarthritis Cartilage, the doctors found:
Approximately 20% of total knee replacement recipients have suboptimal pain relief. (Suboptimal of course means not working).
Pre-operative widespread pain was associated with greater pain at 12-months and failure to reach a clinically meaningful difference in pain, pre and post replacement
Patients with widespread pain along with the pain catastrophizing problems may help identify persons with suboptimal total knee replacement outcomes. (11)
A June 2022 study (43) from the University of Texas at Austin also explored pain catastrophizing problems, writing that “Pain catastrophizing is a maladaptive cognitive strategy that is associated with increased emotional responses and poor pain outcomes. Total knee replacement procedures are on the rise and 20% of those who have the procedure go on to have ongoing pain. Pain catastrophizing complicates this pain and management of this is important for recovery from surgery and prevention of chronic pain.”
An April 2022 study (44) published in the journal Frontiers in psychiatry comes from German researchers. This study stresses the importance of not allowing post-surgical pain become long-term chronic pain with an eye to treatments from psychiatry. “Reducing postoperative pain immediately after surgery is crucial because severe postoperative pain reduces quality of life and increases the likelihood that patients develop chronic pain. Even though postoperative pain has been widely studied and there are national guidelines for pain management, the postoperative course is differently from one patient to the next. . . Preoperative emotional states and treatment expectations are significant predictors of postoperative pain. The relationship between emotional states and postoperative pain is mediated by negative treatment expectations.”
Research: “Patients with persistent pain after knee replacement are dissatisfied”
That is an obvious statement, but what are the patients dissatisfied with and how can we help them? Here is the study that statement came, 2016 research in the journal Osteoarthritis Cartilage: (12)
In the most dissatisfied knee replacement patients:
the pain was associated with instability in the coronal plane (the centerline from head to foot that marks the front of the body from the back of the body) in other words difficulty in:
Also reported were leg and knee stiffness,
and negative social support.
In patients who were dissatisfied on a lesser level,
Studies have demonstrated that poor management of acute pain after total knee replacement is strongly associated with the development of chronic pain
In March 2017, researchers went further, writing in the medical journal Clinic in Orthopedic Surgery(13):
Study: “postoperative pain is a major cause of dissatisfaction among patients after total knee replacement. Studies have demonstrated that poor management of acute pain after total knee replacement is strongly associated with the development of chronic pain, emphasizing the importance of appropriate control of acute pain after total knee replacement”
The patient has knee replacement
The patient suffers from acute pain after surgery
Painkillers and other medications are prescribed to control a patient’s pain. Acute pain turns into chronic pain as the joint continues to degenerate. Pain is an indication of tissue damage that needs repair.
With nowhere else to go, doctors suggest another knee replacement.
Study: “Early diagnosis is very important for the treatment of intractable (hard to control) pain following total knee replacement. A reoperation conducted without identification of a specific reason carries a high risk of failure.”
The patient has a knee replacement.
The patient suffers from acute pain after surgery.
Painkillers and other medications are prescribed to control a patient’s pain. Acute pain turns into chronic pain.
Doctors cannot control pain.
With nowhere else to go, doctors suggest another knee replacement.
Second knee replacement operation with a high rate of failure.
Patients had knee pain after a knee replacement because, after the fact, it was determined that knee replacement was the wrong surgery. The knee was not the problem and the patient was inappropriately rushed to surgery
Are you getting a knee replacement because of undiagnosed back and hip pain? Above we spoke about doctors looking for knee pain that was actually coming from the spine, hip, ankle, and feet. The knee was perhaps not the problem and the patient was inappropriately rushed to surgery
Doctors warn that in the case of chronic knee pain, a thorough examination is imperative in identifying the correct diagnosis. That sounds like common sense, but the truth is that the source of pain is often missed and treatment then will present a significant challenge with less than desired results.
One study sought to understand why up to 20 percent of patients who undergo total knee replacement still have persistent pain and why secondary surgery rates are on the rise. (14) Forty-five patients were studied. What the researchers found was somewhat shocking. The pain was not originating in the knee – here is what they said: The wrong joint was operated on – you did not need a knee replacement.
Patients may still be undergoing knee replacement for degenerative lumbar spine and hip osteoarthritis
“Patients may still be undergoing knee (replacement) arthroplasty for degenerative lumbar spine and hip osteoarthritis. . . We suggest heightened awareness at pre-and post-operative assessment and thorough history and examination with the use of diagnostic injections to identify the cause of pain if there is doubt.”
In other words, patients received a knee replacement when the cause of pain came from the hip and spine.
In the journal Modern Rheumatology, Japanese doctors wrote:
“We suggest that rheumatologists be aware of hip disease masquerading as kneepain or low back pain.” (15)
In the case of chronic joint pain, a thorough examination is imperative in identifying the correct diagnosis. That sounds like common sense, but the sad truth is that the source of pain is often missed because of misinterpretation of MRI and other imaging scans. Please see our article on MRI accuracy.
Did your knee get larger after knee replacement?
A June 2022 paper was published in the journal International orthopaedics (40). The researchers of this paper acknowledged that doctors are seeing patients following a total knee replacement, with the complaint that their knee seems larger. Yet, according to the researchers, no studies have described this phenomenon. To identify this problem, the researchers have it a name and diagnosis: “patient-perceived enlargement of knee.” In this study the researchers reviewed unilateral primary total knee arthroplasty patients cases. The patients had their knees replaced between May 2018 and April 2019. A total of 389 patients were enrolled with 101 of the patients, more than one in four, describing that their knee felt larger after the surgery. The researchers did note that patients with patient-perceived enlargement of knee were significantly shorter and carried a lower weight, however, the knee replacement hardware or component size distribution showed no statistical difference. Ultimately, patients with patient-perceived enlargement of knee had significantly lower functional scores and satisfaction.
Knee replacement complications in former athletes
In a recent paper, doctors from NYU Langone Medical Center, Hospital for Joint Diseases suggest that total knee arthroplasty (replacement) is often the best answer for end-stage, post-traumatic osteoarthritis after intra-articular (inside) and periarticular (around) osteoarthritic fractures the knee.
However, total knee replacement in the setting of post-traumatic osteoarthritis is often considered more technically demanding surgery and the surgical outcomes are typically worse for these patients. The goal of the NYU paper was to create a new classification label for post-traumatic osteoarthritis patients and improve medical documentation and improve patient care.
The researchers looked at post-traumatic osteoarthritis patients who suffered from osteoarthritis as a result of high demand or athletic activity. These were on average were younger and healthier than the primary total knee replacement population (older patients with degenerative arthritis from wear and tear).
The healthier post-traumatic total knee replacement group had the following complications:
higher rates of superficial surgical site infections,
In a similar study, doctors at Duke University also recognized Total Knee Arthroplasty as an important treatment for post-traumatic arthritis. However, these researchers also found complications that should not be expected in a mostly healthy patient population.
a higher rate of infection around the knee implant
cellulitis (skin infection)
seroma (fluid build)
knee wound complications (problems at the surgical incisions)
The patient problems after knee replacement surgery are many. At Caring Medical, we can address many of these problems. We cannot address all, especially when the problem of knee replacement is caused by hardware failure and hardware placement failure.
PROBLEM: The knee replacement hardware is wearing out and loosening or it was not placed in the knee correctly and stress is causing the device problems. This problem will need surgical consultation and possibly revision surgery.
PROBLEM: Infection. This is during the initial recovery period. On prosthetic devices, bacteria can form and colonize. This problem will need a consultation with the surgical group and possibly emergency medicine.
PROBLEM: The implant or the surgery caused fractures in the thigh or shin bone. This problem will need a consultation with the surgical group and possibly emergency medicine.
PROBLEM: Knee prosthesis instability and loss of range of motion (it gets stuck), can also lead to considerable pain.
Problem: Neuropathic knee pain after surgery – nerve damage caused by the surgery
Above we discussed neuropathy, nerve damage, as occurring in a small portion of knee replacement patients. A study from doctors in the United Kingdom published in the Bone and Joint Journal (18) suggests that while a small percentage of patients suffer from neuropathic pain caused by knee replacement, it is still an underestimated problem in patients with pain after total knee replacement.
Further, this distress was associated with a more difficult recovery following (the knee replacement), characterized by more severe pain and greater functional limitations. There was a significant impact of psychological processes on postoperative recovery. (19)
Problem: Difficulty and Pain in Kneeling
Most people had difficulty kneeling because of pain or discomfort in the replaced knee. Many patients described how this limitation affected their daily lives, including housework, gardening, religious practices, leisure activities, and getting up after a fall. Patients often adapted to these limitations by finding alternatives to kneeling, assistance from others, or home adaptations. Many patients had accepted that they could not kneel, however some still expressed frustration. Few patients had consulted with healthcare professionals about kneeling difficulties, and unmet needs included the provision of information about kneeling and post-operative physiotherapy. (20)
Problem: Fixing Pain After Total Knee Replacement may include Amputation
Three in 1000 patients will need to have their leg amputated.
The causes of the amputation were:
infection around the implant (83%),
soft-tissue deficiency surrounding the implant (23%),
severe bone loss (18%),
extensor mechanism disruption, i.e., patellar and quadriceps tendon disruption (10%),
intractable pain (10%),
fracture around the implant (9%),
circulatory damage (8%).
In 80% of the cases, there were more than 2 of these factors for amputation. (21)
In research from April 2017, doctors writing in the European Journal of Orthopaedic Surgery and Traumatology wrote:
Treatment for prosthetic knee replacement is becoming more common. Infection is an arthroplasty-related complication leading to prolonged hospitalization, multiple surgical procedures, permanent loss of the implant, impaired function, impaired quality of life, and even amputation of the limb.
The purpose of this study was to identify risk factors for amputation in the periprosthetic infected knee through a case-control study, analyzing patients treated from January 2012 to November 2016 in a hospital with a high incidence of this diagnosis. We included 183 patients with periprosthetic knee infection; 23 required amputation as definitive management (cases).
They found that patients with:
Increased surgical time >120 min,
diabetes mellitus had an increased risk of amputation. (22)
Catastrophizing thoughts and central sensitization = catastrophic results and opioid dependence after knee replacement
Researchers in Canada writing in the Journal of Pain Research found pain catastrophizing reflects a patient’s anxious preoccupation with pain, inability to inhibit pain-related fears, amplification of the significance of pain, and a sense of helplessness regarding pain. (23)
Catastrophizing thoughts are unrealistic beliefs that only the worst can happen. A person who goes into any medical treatment believing it will not work is at a significant disadvantage. A patient should relay these thoughts to his/her doctor so that appropriate action can be taken. For some patients, counseling will be effective, for some therapy, for some prayer. The patients must be made aware of options that will help them move from hopelessness to cautious optimism.
A significant problem with catastrophizing thoughts that needs to be addressed is a greater risk for opioid dependence.
Doctors in Belgium write in the Bone and Joint Journal that pre-operative pain in the knee predisposes to central sensitization (catastrophizing thoughts). Pain due to osteoarthritis of the knee may also trigger neuropathic pain and may be associated with chronic medication like opioids, leading to a state of nociceptive sensitization called ‘opioid-induced hyperalgesia’ painkillers increase chronic pain. (24)
“Patients may need subsequent surgeries to maximize the benefits of joint replacement”
“Many patients with hip and knee arthritis have the condition in more than one of their hip or knee joints,” said the study’s lead author Dr. Gillian Hawker. “So it’s not surprising that replacing a single joint doesn’t alleviate all their pain and disability — patients may need subsequent surgeries to maximize the benefits of joint replacement.”
The study, published in the journal Arthritis & Rheumatism (25), followed a group of patients with osteoarthritis and inflammatory arthritis. Only half reported a meaningful improvement in their overall hip and knee pain and disability one to two years after surgery. What’s more, researchers found the patients who had the worse knee or hip pain to begin with but fewer general health problems and no arthritis outside of the replaced joint were more likely to report benefits.
According to the study authors, nearly 83 percent of study participants had at least two troublesome hips and or knees.
In general, an estimated 25 percent of patients who undergo a single joint replacement will have another joint replacement — usually the other hip or knee — within two years.
“While demand for joint replacement surgery has increased as our population ages, physicians lack a set of established criteria to help determine what patients will benefit from surgery and at what point during the course of the disease,” said Dr. Hawker, physician-in-chief at Women’s College Hospital and a senior scientist at ICES. “As physicians, we need to do a better job of targeting treatments to the right patient at the right time by the right provider.”
Why physical therapy failed post-knee replacement. It’s not the treatment but expectations that are not met.
A February 2022 paper in the Journal of evaluation in clinical practice (35) comes to us from the Physical Therapy Program, Department of Physical Medicine and Rehabilitation, University of Colorado.
In this survey of patients and physical therapists describing the patient experience and expectation of physical therapy following total knee replacement, the therapists found that in many cases patients were not given a true indication of the amount of therapy that would be required post-knee surgery and that further, many patients were given little of no information of how to proceed in the post-recovery period from their surgical team, specifically as their treatment related to physical therapy. Many patients in fact were not part of the “shared decision making” processes.
The information that emerged in this survey was:
A lack of standardized approach for involving patients in their rehabilitation decisions. This could impact patient motivation as the study notes patient decision making could be “a key component of rehabilitation success and a key ingredient in promoting patient engagement.” In other words, talk with your physical therapists or nay health care provider about your goals of treatment.
The benchmarks were to generic and not customized
Subtheme: generic recovery benchmarks
The physical therapists noted that using generic benchmarks for guiding future treatments may not lead to successful PT. That the treatments should be more customized to the patients lifestyle. For example, the physical therapist should determine the home setting in guiding treatment. Does the patient have to go up and down stairs to do laundry or other daily chores. How does the patient navigate around their homes and work environment?
The main problem discussed was the dependence on the importance of regaining range of motion (ROM), especially knee flexion, to a predetermined threshold as the primary indicator of recovery. Many patients also mentioned their rehabilitation focused heavily on restoring ROM to meet expectations set by their surgeons and physical therapists. But to some patients this did not meet their own functioning goals.
Everything was not “good as new.” The problems of unrealistic expectations of recovery by the patient
The physical therapists of this survey reported that many patients were not prepared for the physical demands and length of the physical therapy required to complete the rehabilitation. Further, that the surgical team did not discuss this aspect of post-recovery with the patients.
Trying to help people who should have not had the knee replacement in the first place.
The physical therapists of this survey reported that some patients they were trying to help, should not have had, in their opinion, the knee replacement due to their health condition or physical limitations, as this sets the patient up for treatment failure and post-surgical complication.
The overall view was that for post-knee replacement physical therapy to succeed, patients should be offered:
Pre-surgery counseling on the post-knee replacement recovery process.
Deep involvement in how their recovery should proceed with the performance of real life chores and activities the main focus as opposed to basic guidelines for simply being able to bend their knee.
Neuromuscular electrical stimulation
Some doctors suggest that Neuromuscular electrical stimulation (NMES) is an effective method for quadriceps strengthening which could prevent muscle loss in the early total knee arthroplasty (replacement) postoperative recovery period.
A January 2022 paper in The journal of knee surgery (36) considered this question and evaluated the postoperative use of Neuromuscular electrical stimulation (NMES) on knee replacement patients and results of increased quadriceps strength and ultimately improved functional outcomes.
In this study were 66 patients, 44 patients had Neuromuscular electrical stimulation (NMES) and 22 control patients.
Patients who used the device for an average of 200 minutes/week or more (starting 1 week postoperative and continuing through week 12) were considered compliant.
Patients in the treatment arm (NMES use) experienced quadriceps strength gains over baseline at 3, 6, and 12 weeks following surgery, which were statistically significant compared with controls with quadriceps strength losses at 3 and 6 weeks.
Use of a home-based application-controlled NMES therapy system added to standard of care treatment showed statistically significant improvements in quadriceps strength and functional timed up and go following total knee arthroplasty , supporting a quicker return to function.
In the image below:
The caption reads: Models of knee replacement illustrating knee stability with intact ligaments with “loose” ligaments. In the first panel (A) Anterior view of intact ligaments. In the center (B) panel, lateral view of intcat ligaments. In the right (C) panel Anterior view with loose ligament. Pain after a joint replacement is almost always from laxity in surrounding ligaments. Prolotherapy ligament-strengthening injections relive the pain and improve stability.
Acupuncture for post-knee replacement pain
An April 2022 study published in the journal BioMed research international found “beneficial effects” of acupuncture in helping patients with knee osteoarthritis. (41) The researchers concluded their paper by saying: “Acupuncture has beneficial effect on pain relief and improves function activities, and this treatment can be recommended as a beneficial alternative therapy in patients with knee osteoarthritis, particularly for chronic patients and those currently undergoing long-term pain and help them increasing quality of life. But it should be further verified through more random control studies in function. Available studies suggested that acupuncture was superior to sham acupuncture in reduce pain and function.”
How can we help these problems? The often overlooked and ignored cause of pain after knee replacement – the Knee Ligaments.
When a knee replacement is performed, the joint itself has to be stretched out so the surgeons can cut out bone and put it in the prosthesis. When the joint is stretched out, the knee ligaments and tendons that survive the operation will cause pain as they heal from the surgical damage. Sometimes the ligaments and tendons heal well. Sometimes they do not heal as well.
In this video, Ross Hauser, MD explains the problems of post-knee replacement joint instability and how Prolotherapy injections can repair damaged and weakened ligaments that will tighten the knee. This treatment does not address the problems of hardware malalignment that our patient Jeannette described in the video above.
Summary of this video:
The patient in this video came into our office for low back pain. I did a “straight leg raise test,” on this patient to help determine if his back pain was coming from a herniated disc.
During the test I noticed a clicking sound coming from his knee. The patient had a knee replacement.
It is very common for us to see patients after knee replacement who have these clicking sounds coming from knee instability. This is not instability from hardware failure. The hardware may be perfectly placed in the knee. It is instability from the outer knee where the surviving ligaments are. I believe that this is why up to one-third of patients continue to have pain after knee replacement.
Dr. Hauser performs an ultrasound scan of the patient’s knee. Small, gentle stress on the knee reveals hypermobility. This is from the ligaments’ inability to hold the whole knee joint in place. Prolotherapy can be very successful in helping patients who had a knee replacement and still have knee pain. The treatment tightens the whole joint capsule.
A loose knee replacement
A June 2022 paper in The Journal of arthroplasty (39) examined the impact of a loose or migrating knee replacement in patient satisfaction following total knee replacement. The researchers looked a patients who were satisfied with their knee replacement and those patients who were dissatisfied with their knee replacement. The thinking, prior to the study was that a loose or migrating implant would create problems with knee movement leading to the patient unhappiness. What they found was functionally dissatisfied patients had more anteriorly positioned contact on the lateral condyle (o the thigh bone) in early flexion (as they ben their knee) and reported more pain and unmet expectations. The researchers noted: “These findings suggest that improving the functional satisfaction of (a total knee replacement) requires restoration of kinematics (proper movement) in early flexion (bending) and management of patient’s pain and expectations.”
Post-surgical pain and knee instability may be from the surviving ligaments
The idea that knee ligament damage from the knee replacement is one of the “mystery” pains following knee replacement has been the subject of a wave of recent studies.
A study in the journal Orthopedics(26) from Rush University Medical Center researchers identified the problems of knee instability as a cause of pain in knee replacement patients. Here is a summary of their findings:
Instability is one of the most common causes of failure of total knee replacement.
Acute instability is related to intraoperative injuries or excessive release of important coronal stabilizers such as the medial collateral ligament in extension or the posterolateral corner in flexion. The posterolateral corner includes
lateral collateral ligament,
popliteus tendon, and
Chronic instability in extension is often related to varus/valgus malalignment. (Knee hardware problem)
Chronic instability in flexion can be related to an undersized femoral component, excessive tibial slope, or excessive elevation of the joint line affecting the isometry of the collateral ligaments in mid flexion. (Knee hardware and anatomy problems caused by surgical mistake).
Ligament instability was the primary reason for repair surgery
Doctors writing in the German medical journal, Der Orthopäde said:
“In 32.6 % of all cases [requiring a revision knee replacement surgery], ligament instability was the primary reason for revision.
In another 21.6%, ligament instability was identified as a secondary reason for revision.
Analysis of the different instability forms showed combined instability in extension and flexion as the most common cause, followed by isolated instability in flexion (31.8%) and isolated instability in extension (9.1%).
The summary statement of this research is extraordinary in its simplicity
“Correct anatomical positioning of the components and balanced ligaments in the different extension and flexion positions are important for good clinical results, a stable joint, good function, and longevity.”(27)
In other words, put the ligaments back where you found them.
Previous ligament reconstruction surgery – higher risk for complications after knee replacement
Doctors at the Mayo Clinic have published findings in Clinical Orthopaedics and Related Research which they suggest that patients who had previous multi-ligament reconstruction surgery were at high risk for:
and a higher risk of major complications, including reoperation and infection. (28)
The ligament problem is a clue that for some patients, post knee replacement pain may be a problem of overdoing it, even while in the hospital or nursing home
In a study from October 2018, doctors writing in the Journal of Pain Research, (29) looking at why some people had excessive pain after knee replacement surgery asked if this was a problem of “overdoing it” in the hospital following the surgery? The research measured the results of making patients progressively walk more steps in the hospital or nursing home up to 10 days after the surgery.
These are surgeons and pain management specialists from leading hospitals and universities in Japan talking about patients soon after knee replacement during the surgery recovery.
Poor pacing (too many steps, too much too soon) during physical activity is associated with severe pain in postoperative patients
Over-activity results in a number of potential injuries to muscle fibers, nerves, bones, and ligaments. These injuries, as well as the repetitive experience of pain, will prolong pain and contribute to neurobiological mechanisms of peripheral and central sensitization.
Comment: Here again is the problem of the pain being worse than it should be. In the typical rehab after surgery, patients are told to walk in increasing amounts in the days following the surgery. Here the doctors discuss this new activity on a knee that likely had not seen much activity leading up to the surgery. This new activity trains the nerves to be more sensitive to pain.
The knee cap was floating because the MCL was released. Patellar maltracking after total knee replacement. The concern of “catastrophic laxity”
Let’s look at two studies surrounding the medial collateral ligament.
The first is from 2015, the second is from 2021
In June 2015 in the journal Knee Surgery, Sports Traumatology, Arthroscopy (30) researchers wrote: “Medial collateral ligament (MCL) release is one of the essential steps toward the achievement of ligament balancing during the total knee arthroplasty (TKA) in patients with varus deformity (knee replacement caused bow-leg). When the varus deformity is severe, complete release of the MCL until balanced is often required. However, it is believed that a complete MCL release may lead to catastrophic laxity. ”
In March 2021, a study published in the journal Knee Surgery and Related Research (31) continued that Medial collateral ligament release during knee replacement could lead to the surviving knee cap floating around the knee. Here are the study’s observations: “Patellar maltracking after total knee arthroplasty (TKA) can lead to significant patellofemoral complications such as anterior knee pain, increased component wear, and a higher risk of component loosening, patellar fracture, and instability. . . A complete release of the MCL during surgery was associated with patellar maltracking. Surgeons should attend to patellar tracking during surgery in medially tight knees.”
A realistic assessment of what we can do to help with your pain after knee replacement
In our clinic, we try to provide information on helping people explore other treatment options before joint replacement. One of those options is simple dextrose Prolotherapy. This regenerative injection technique helps rebuild damaged ligaments and tendons.
When the patients have already had a joint replacement, we will do a physical examination of the knee to assess how we may be able to help.
Prolotherapy fixes soft tissue, it cannot fix hardware failure,
Prolotherapy works by stabilizing the knee by strengthening the natural muscle and bone attachments, ligaments, and tendons.
In this video, our patient Jeannette had issues with spinal stenosis and problems post knee replacement.
Jeannette starts discussing the knee replacement complications at 2:30 into the video. Jeannette is 81 years old.
Jeannette describes a foot-tingling problem. She cannot sit down and relax at the end of the day, it is uncomfortable for her to put her feet up or down because it is tingling. She had a nerve conduction study that shows an injury to her peroneal nerve.
The peroneal nerve branches out from the sciatic nerve. As it provides sensation to the front and sides of the legs and to the top of the feet, damage to this nerve would result in burning and tingling or numbness sensation in these areas. Further damage to this nerve would also cause loss of control in the muscles in the leg that help you point your toes upward. This can lead to walking problems and possibly foot drop, the inability to lift the front of the foot or ankle. Knee and hip replacement are leading culprits in the cause of peroneal nerve injury.
In Jeannette’s case, she had two knee replacement surgeries in that knee. After the first knee replacement surgery, the implant started to protrude away from the limb. The knee replacement became loose. The second surgery to fix the first one occurred in 2015.
It was determined after examination that Jeannette’s knee ligaments were loose. Her knee was hypermobile and unstable. This was causing pressure on her peroneal nerve. Knee ligament damage and weakness is also a complication of knee replacement surgery and is discussed further below.
All medical procedures have success stories and failure stories. Patient case history and descriptions of their treatments may not be typical or indicative of all outcomes.
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