Why does my knee hurt?
Knee pain is a common issue in my clinic, as well as the United States. 19.5% of the US population in 2010 had some sort of knee pain, which encompasses both acute and chronic conditions. Acute knee pain is when there is some sort of traumatic event. A patient can specifically name an incident that brought about their knee pain. Chronic knee pain happens over a long period of time, which is not linked to a specific event. The patient simply notices the pain randomly. In my eyes, chronic knee pain can be broken down into what is the cause of the knee pain, whether it is a physical, chemical, or mental stressor.
Physical Stressors
As a chiropractor, I would say that it is very important to make sure your body is physically aligned. This makes sure that there isn’t any added force to a particular area that causes pain, and in this case the knee. Those forces can lead to injury, which is why the knee is the most commonly injured joint by adolescent athletes. The knee is supposed to be a stable joint, while the hip and ankle are supposed to be mobile joints.
The body is set up to have alternating stable and mobile joints, to allow for full ranges of motion without injury. However, there are often times where mobile joints lose mobility, which turns that joint into more of a “stable” joint, which forces the adjacent stable joints to become more mobile. The opposite can be said about stabile joints losing stability, and causing mobile joints to become more stable (it’s the whole chicken and egg discussion).
A great example of this would be an elderly person having decreased range of motion in their hip throughout the years. Then they end up hurting their knee and having to get a knee replacement since it has lost its stability. Some very common patterns I see with people that have physical pain going on with their knee is that something else is the cause of the knee pain. What I mean by that is patients often have a rotated pelvis and/or ankle/foot dysfunction (flat-footedness aka pes planus) which throws off the biomechanics of the leg, and that dysfunction manifests as knee pain. The most common site of pain I see is on the inside around the pes anserine (superior medial aspect of the tibia), where the sartorious, gracilis, and semitendinosus muscles converge.
Chemical Stressors
Not all knee pain is caused by a physical stressor, there can be chemical stressors as well. Chemical stressors would be arthritidies, like osteoarthritis and rheumatoid arthritis for example. Osteoarthritis in particular is the most common joint disease, affecting more than 30 million US citizens, and accounts for $185 billion annually in healthcare costs. Any sort of arthritis means that there is an inflammatory component involved, so down regulating pro-inflammatory cytokines (such as IL-1β, TNFα, NF-κB, and IL-6) is important to dampen the inflammatory response. Inflammation is necessary for tissue to heal, however, too much inflammation is detrimental to the healing process.
The majority of US citizens (70.2%) is considered overweight or obese, based off of the Body Mass Index (BMI). The BMI has its flaws (particularly with tall and muscular individuals), but nonetheless there are plenty of US citizens that are overweight or obese. When an individual is obese then those pro-inflammatory markers are shown to increase. Increased inflammation means that symptoms of the arthritidies. There are recent studies stating that osteoarthritis has doubled since the mid-20th century, and that lack of activity/exercise could be the root cause. Correlation doesn’t always mean causation (like anything in science), and that there are likely other factors involved that leads to osteoarthritis than just lack of exercise (diet would be another factor). Regardless of the cause, osteoarthritis could be prevented more than what was previously thought about this condition.
Applied Kinesiology
In my clinic, I utilize a technique called applied kinesiology, which is essentially muscle testing to figure out what is dysfunctional in the body and how to overcome that dysfunction. In applied kinesiology, there are muscle-organ associations which means that if there is something going on with a particular organ, it could manifest as pain or dysfunction of that associated muscle. Dealing with the knee, people often have issues with their gall bladder (biliary system in general, which includes the liver) and that can manifest as pain behind the knee or a sense of knee instability due to the muscle dysfunction. Sometimes, there’s a cyst behind the knee (Baker’s cyst) and they are associated with arthritis as well as gall bladder dysfunction (from an applied kinesiology standpoint).
People usually don’t think of knee pain as a manifestation of brain/mental dysfunction. When there is dysfunction with the basal ganglia of the brain, that can result in pain in the back of the knee. Two functions of the basal ganglia are setting muscle tone and emotions. When someone is stressed it is the basal ganglia that is responsible for tight muscles, particularly flexor muscles that propel humans forward. The stress response is also known as the fight or flight response, and our flexor muscles help us either fight or flee stressors (because that is how human ancestors dealt with stressors, like sabre tooth tigers). Relating this to the knee, if someone is stressed that causes the gastrocnemius muscle (knee flexor) to be tight, and could cause pain on the tendon where the gastrocnemius crosses the knee joint.
There are many other causes of knee pain, and they should be checked out by a medical professional. As with any sort of pain, a doctor of chiropractic should be sought out first, then a medical doctor if unsuccessful, and as a last resort an orthopedic surgeon. Although rare, there are cancers that can manifest as knee pain and/or dysfunction and should be dealt with appropriately. Knee pain, especially chronic, should not be ignored.
About the Author
Dr. Eric Johnson, Doctor of Chiropractic and Diplomate of the American Clinical Board of Nutrition as well as owner of Functional Wellness and Chiropractic Center in Madison, WI, is a functional medicine doctor that identifies root causes of pain and/or dysfunction. His systems-based, not symptoms-based, approach is a comprehensive, holistic approach that helps identify mental, chemical, and physical stressors that are underlying numerous health conditions. If you are in the Madison, Middleton, Verona, Waunakee area and looking to not only feel better, but live better, contact Dr. Eric at (608) 203-9272.
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