Problems after knee replacement | Finding help for post-replacement pain
Problems after knee replacement | Finding help for post-replacement pain
Ross Hauser, MD | Caring Medical Regenerative Medicine Clinics, Fort Myers, Florida
Katherine L. Worsnick, MPAS, PA-C | Caring Medical Regenerative Medicine Clinics, Fort Myers, Florida Danielle R. Steilen-Matias, MMS, PA-C | Caring Medical Regenerative Medicine Clinics, Oak Park, Illinois
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.
When patients come into our office with pain after knee replacement we will often ask them, why did you get a knee replacement in the first place? The top two answers we will call 1A and 1B because they seem to be of equal importance:
My doctor said I had no choice
My insurance covered it
In hindsight, for a patient with pain following knee replacement it no longer matters why they had the knee replacement, it is a matter of what can you do about it now?
A large number of people are affected by chronic pain after total knee replacement
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, (1) 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.”
The same doctors also wrote in the British Medical Journal 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.”(2) 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
Researchers at the Department of Surgery, Southern Illinois University School of Medicine offered this assessment in the medical information publication Instructional Course Lectures(3) 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), have 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 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.
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 (2), 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 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 a 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. (4) 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, (5) 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(6) 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 endoprosthetics (knowledge of hardware failure and misfit), qualified physiotherapists (patients with problems after knee replacement often suffer from 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)
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(9):
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”
Patient has knee replacement
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
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.”
Patient has knee replacement
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 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.(10) 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:
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.” (11)
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.
Despite the warning about knee replacement complication risks being higher when performed at local low-volume hospitals – patients still choose the local – higher risk option. In fact, the researchers called these patients the “vulnerable group.”
In 2012, doctors writing in the journal BMC Musculoskeletal Disorders warned patients not to go to low-volume knee replacement hospitals because the risk of complication was greater due to lack of expertise. (Yes we say the same thing about Prolotherapy – go to a high volume Prolotherapy practice).
Despite this warning about knee replacement complication risks being higher when performed at local low-volume hospitals – patients still choose the local – higher risk option. In fact, the researchers called these patients the “vulnerable group.”(12)
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 that 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), this 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 (15) suggests that while a small percentage of patients suffer from neuropathic pain caused by the 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 the postoperative recovery.(16)
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 frustrated. Few patients had consulted with healthcare professionals about kneeling difficulties, and unmet needs included the provision of information about kneeling and post-operative physiotherapy.(17)
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 quadricep 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.(18)
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 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.(19)
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 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.
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(20) 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 midflexion. (Knee hardware and anatomy problems caused by surgical mistake).
Ligament instability was the primary reason for repair surgery and that surgeons should put the knee ligaments back where they found them
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.”(21)
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.(22)
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, (23) 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 is 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 that 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.
A realistic assessment of what we can do to help with your pain after knee replacement
In our clinics, 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 stabilizes the knee by strengthening the natural muscle and bone attachments, ligaments and tendons.
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