Chronic Knee Pain, Knee Instability, and Degenerative Knee Disease
In this article we will discuss the degenerative knee disease process that leads to eventual knee replacement and how we can stop and heal the damage this process causes.
- Are you being pain managed until knee replacement?
- Is a knee replacement in your future?
- It does not have to be.
Before reading on do you have a question about your knee instability? Get help and information from our Caring Medical staff
Knee instability symptoms
- Your knee gives way
- Your knee catches or locks
- Your knees are always puffy
- Your knees bend in VALGUS or turn out VARUS (bow-legged)
- Your doctors has made a recommendation for knee replacement.
Being weak in the knees. Why does your knee buckle? Are you a fall risk?
For patients who are being managed until knee replacement, or are putting off any treatment to fix his/her knee, there is the problem of knee buckling. Knee buckling is the knee giving out. Most times people will be able to grab unto something or someone close by to prevent a fall. If not, there can be a fall. People with knee osteoarthritis and knee instability are a fall risk.
Why does your knee buckle? Simply the knee at that moment cannot support your weight, your knee is collapsing under your weight.
The story of “wear and tear.”
In an April 2017 study published in the medical journal Cartilage, doctors in Japan made the obvious but often overlooked observation about knee instability.
- Osteoarthritis is the result of knee instability or using a more medical term “accumulated abnormal mechanical stress” or simply “abnormal joint movement of the knee.” (In common language this means “wear and tear.”)
- Abnormal joint movement of the knee (knee instability) causes wear and tear osteophyte (bone spur) formation;
- Abnormal joint movement of the knee (knee instability) causes wear and tear knee cartilage breakdown;
- Therefore, treating abnormal joint movement of the knee (knee instability) may be a beneficial precautionary measure for osteoarthritis progression in the future.(1) Preventing continuation of wear and tear.
This same research team in February 2017 wrote in the journal Osteoarthritis and cartilage: discussing instability from ACL wrote:
Re-stabilization of (knee) instability may suppress inflammatory cytokines (chronic inflammation), thereby delaying the progression of osteoarthritis. (Knee) instability is a substantial contributor to cartilage degeneration.(2) In other words aggressive wear and tear.
In brief, osteoarthritis is caused by knee instability. If you treat the instability early you can prevent rapid degeneration wear and tear of the knee joint. You can stop your knee from buckling
When your knee is fit and strong, it is stable. When it is worn and weak it is unstable.
A heavily referred to and cited British study published in the The Western journal of medicine, suggests that stability of the knee joint is maintained by:
- the proper shape of the condyles (the boney structures of the knee joint),
- and the bones structural relationship with the meniscus, cartilage, and ligaments of the knee.(3)
This too sounds obvious, however the core message is that stability of the knee joint is maintained by the entire knee working in concert, AND, this concept is easily lost during a physical examination by doctors who see a torn meniscus and want to operate without realizing the damage surgery can cause the articular cartilage, bone, and ligaments the removal of the meniscus can cause. This particular problem is discussed at length in our article on meniscus repair without surgery.
The core message is that stability of the knee joint is maintained by the entire knee working in concert. Instability is also a factor of the entire knee and not simply one damaged component.
The knee condyles (medial for the middle and lateral for the outside) are bony structures that sit in the bottom of the thigh bone in the knee joint that assist in keeping the knee from hyperextending (bending too far.) The medial condyle is larger bone structure because it bears more weight. As we age, and a lifetime’s stress impact our knees, these bones wear away. Their degeneration has been clearly associated with meniscus degeneration.
The meniscus is the cartilage padding that acts as a shock absorber. When it is damaged, the protective articular cartilage that covers the thigh and shin bones are now stressed because it is assuming the mechanical load normally taken care of by the meniscus.. What we have here is the beginnings of bone-on-bone knee.
The above process is a multi-fold attack on knee stability.
- First the boney structure that prevents excessive movement wear away causing excessive or hypermobile movement.
- That hypermobility as well as surface pressure (impact loads of our body weight on our knees) cause meniscus damage, the meniscus damage causes articular cartilage damage.
So the simple understanding is – knee stability is maintained by the the shape of the condyles and menisci, and knee instability occurs when these structures suffer degenerative wear and tear or osteoarthritis.
Let’s introduce ligament laxity or ligament damage into the wear and tear equation.
Everything in the knee affects the ligaments and the ligaments affect everything in the knee
Ligaments function primarily to maintain smooth joint motion, restrain excessive joint displacement, and provide stability across the knee joint.
The ligaments of the knee provide:
- passive stability,
- guide the motion of the femur and tibia,
- define contact mechanics between the femur and tibia,
- and restrain excessive motion to prevent dislocation.
When the forces to which ligaments are subjected are too great (acute injury or degenerative failure caused by ligament laxity), failure occurs, resulting in drastic changes in the structure and physiology of the joint.
Ligaments are the primary passive joint stabilizers whereas muscles are the active joint stabilizers.
- Mechanical laxity refers to an excess in the range of motion in the knee due to loss of integrity of the ligaments and other soft tissues which contribute to joint stability.
- Functional instability refers to a sense of instability or giving out of the joint experienced in the course of daily activities or strenuous exercise. It is possible to have functional knee instability from muscle weakness alone; thus functional instability may or may not be associated with mechanical laxity.
Continuing the discussion from the British study published in the The Western journal of medicine:
The four major ligaments of the knee are:
- the famous anterior cruciate ligament (ACL),
- the posterior cruciate ligament (PCL),
- the medial collateral ligament (MCL),
- and the lateral collateral ligament (LCL).
The medial collateral ligament and posterior cruciate ligament are attached to the medial condyle, the lateral collateral ligament is attached to the lateral condyles.
Now we have ligaments that are compromised by the bone degeneration and begin to loose their characteristic tautness because their bone attachments are degenerating.
Conversely, working backwards in a different patient scenario, it is instability in these ligaments that may have started the degenerative cascade of the condyles and menisci. Wear and tear, past impact injuries, everything in the knee affects the ligaments and the ligaments affect everything in the knee.
Knee ligament instability – the cause of wear and tear and bone on bone
Sports medicine doctors in Europe, writing in the journal Knee surgery, sports traumatology, arthroscopy suggest that when dealing with knee instability in patients doctors should be wary that “the interpretation of multidirectional knee laxity (the knee overextends in multiple directions) is complex and suggests the necessity for individualized care of knee diseases and injuries.”(4)
- What these researchers are saying is let’s get a good physical examination and look at the knee. Please see my article Is My MRI Accurate? This includes looking for ligament laxity.
But going a little further look at what the study suggests:
“Physiological knee laxity has received little attention in spite of indications that it influences knee diseases/injuries and their outcomes. Excessive laxity has been recognized as a risk factor for non-contact ACL injuries and more importantly for worse ACL reconstruction outcomes.” (Please see my article After ACL Reconstruction | Complications and knee instability)
“Our findings may therefore stimulate the debate around the need for individualized care of knee injuries and disease. More work is needed to improve the comprehension of the role of individual knee function in the occurrence of degenerative knee diseases, knee injuries (e.g. non-contact ACL injuries) and poor treatment outcomes.”
- The reason for poor outcomes, knee instability is not understood
More research: The following studies demonstrate how important the ligaments are to the stability of the knee
In the first study, a classic 1993 paper published in the American Journal of Sports Medicine, concerning posterior cruciate ligament laxity, the researchers note:
- “Knees with underlying physiologic cruciate ligament laxity had the greatest lateral tibial plateau subluxation.” In other words when the ligaments were compromised the knee became misaligned – displaced. (5)
The second study, another classic study lead by the same research team leader, Dr. Frank R. Noyes, on anterior cruciate ligament laxity states, “After anterior cruciate sectioning alone, both the lateral and medial tibial condyles displaced (subluxed) anteriorly.”(6)
In other words a partial tear of the ACL resulted the condyles being displaced. See above the medial collateral ligament and posterior cruciate ligament are attached to the medial condyle, the lateral collateral ligament is attached to the lateral condyles.
And again concerning the ACL, the third research team reports, “Significant increases in internal rotation occurred in seven knees when only the anterior cruciate ligament had a partial tear.”(7)
Comprehensive Prolotherapy for problems of knee instability and wear and tear and bone on bone
Comprehensive Prolotherapy used in some cases with Platelet Rich Plasma Therapy and Stem Cells works at the root of the problem, the ligament or soft tissue damage. A series of injections are placed at the tender and weakened areas of the affected structures of the knee. These injections contain a proliferant to stimulate the body to repair and heal by inducing a mild inflammatory reaction. The body heals by inflammation, and Prolotherapy stimulates this healing. The localized inflammation causes healing cells to arrive at the injured area and lay down new tissue, creating stronger ligaments and rebuilding soft tissue. As the ligaments tighten and the soft tissues heal, the knee structures function normally rather than subluxing and moving out of place. When the knee functions normally, the pain goes away.
In published research in the Journal of Prolotherapy, we investigated the outcomes of patients receiving Prolotherapy treatment for unresolved, difficult to treat knee pain at a charity clinic in Illinois. Here are the bullet points of our research:
- The results of this retrospective, uncontrolled, observational study, show that Prolotherapy helps decrease pain and improve the quality of life of patients with unresolved knee pain.
- Decreases in pain, stiffness, and crunching levels reached statistical significance with Prolotherapy.
- The percentage of patients with less knee pain was 95%, and 99% reported long term improvements in stiffness after Prolotherapy.
- Eighty-six percent of patients decreased their need for additional pain therapies, including medication usage by 90% or more, after Prolotherapy.
- Eighty-two percent showed an improvement in sleep.
- For those with depression and anxiety, 86% were less depressed and 82% were less anxious.
- In regard to activities of daily living, Prolotherapy improved walking ability in 84%, athletic ability in 76%, and dependency on another person in 75% of patients treated.
- Of the patients treated with the Hackett-Hemwall technique of dextrose Prolotherapy, 95% felt an overall improvement in their quality of life.
- Ninety-four percent of patients noted their improvement in overall disability has mostly continued since their last treatment.
The key to curing chronic knee pain is locating the points within the knee that are the cause of knee instability. Healing from knee pain necessitates finding the source of the knee pain, while knowing and understanding the correct diagnosis. Too often, the correct diagnosis of knee instability is missing. Once the instability is found, then a program of Prolotherapy injections should be able to repair the damage and stabilize the joint.
Patients who come to Caring Medical are generally well educated on their condition. Of these, about half know the exact location of their knee instability and its cause; the other half do not. Even my fellow Prolotherapists do not always recognize whole joint knee instability, in that approximately 10% of new patients we see have already received Prolotherapy from someone else, but have had little resolution of their symptoms.
One of these patients had several scans, including an ultrasound and MRI, which showed patellar tendinosis, and had subsequently received 20 sessions of minimal Prolotherapy and platelet rich plasma (PRP) injections to the patellar tendon, but to no avail. Why was she still in pain?
She had knee joint instability that was putting increased pressure on her patellar tendon, causing its breakdown. The instability was evident on physical examination, showing that almost all of her ligaments were stretched out. We used Comprehensive Prolotherapy which treats the whole joint, including the ligaments, and after three sessions she was running and playing tennis again!
In simple terms, the ligaments, tendons, synovial tissue, cartilage, meniscus, etc., that hold your knee in proper anatomical alignment have been weakened by degenerative disease caused by wear and tear, acute injury, or poor lifestyle choices such as obesity and inactivity.
Treating the whole knee treats widespread body pain
If there is any more doubt that knee pain is guiding force in disruption of the body homeostasis (the balance between health and non-health) and a cause of why your whole body hurts when you have knee pain. Listen to this research:
Seven Universities, the University of Montreal, Kansas, Alabama, California at Davis UCD, California at San Francisco UCSF, Iowa, and the Boston University School of Medicine teamed up to present findings in the medical journal Arthritis care & research that suggests knee osteoarthritis causes wide spread body pain.
The research team looked at patients who had or were at risk of knee osteoarthritis. These were patients who had consistent frequent knee pain, radiographic documented osteoarthritis, symptomatic osteoarthritis, and knee pain severity at the 60-month visit (baseline).
- Widespread pain was categorized as:
- pain above and below the waist,
- on both sides of the body and axially.
- Incident widespread pain was defined as the presence of widespread pain at 84 months in those who were free of widespread pain at baseline.
Consistent frequent knee pain, symptomatic knee osteoarthritis, and knee pain severity increased the risk of developing widespread body pain, independently of structural pathology. Meaning the severity of the damage to the diseased knee was not the factor, but the level of pain the patient was experiencing was.1
Side note: Over the years we have seen patients who had terrible Knee MRIs showing incredible damage, but for the most part they had no pain. We have also seen patients who had little damage, who had very much pain. What the study suggests is you must help the patient find the cause of the pain, and sometimes it is not in the structural damage.
1 Murata K, Kokubun T, Morishita Y, Onitsuka K, Fujiwara S, Nakajima A, Fujino T, Takayanagi K, Kanemura N. Controlling Abnormal Joint Movement Inhibits Response of Osteophyte Formation. Cartilage. 2017 Apr 1:1947603517700955. [Google Scholar]
2 Murata K, Kanemura N, Kokubun T, Fujino T, Morishita Y, Onitsuka K, Fujiwara S, Nakajima A, Shimizu D, Takayanagi K. Controlling joint instability delays the degeneration of articular cartilage in a rat model. Osteoarthritis and cartilage. 2017 Feb 28;25(2):297-308. [Google Scholar]
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5 Noyes FR, Stowers SF, Grood ES, Cummings J, VanGinkel LA. Posterior subluxations of the medial and lateral tibiofemoral compartments. An in vitro ligament sectioning study in cadaveric knees.Am J Sports Med 1993 May-Jun;21(3):407-14. [Google Scholar]
6 Noyes FR, Grood ES, Suntay WJ. Three-dimensional motion analysis of clinical stress tests for anterior knee subluxations. Acta Orthop Scand 1989 Jun; 60(3):308-18. [Google Scholar]
7 Lipke JM, Janecki CJ, Nelson CL, McLeod P, Thompson C, Thompson J, Haynes DW. The role of incompetence of the anterior cruciate and lateral ligaments in anterolateral and anteromedial instability. A biomechanical study of cadaver knees. J Bone Joint Surg Am. 1981 Jul; 63(6):954-60. [Google Scholar]
8.Arthritis Care Res (Hoboken). 2017 Jun;69(6):826-832. doi: 10.1002/acr.23086. Epub 2017 May 8. Knee Pain and Structural Damage as Risk Factors for Incident Widespread Pain: Data From the Multicenter Osteoarthritis Study.