Knee Pain: Symptoms, Causes, Risk Factors, Healing Cycle & Treatment
What is the Knee Joint?
The knee joint is one of the largest joints of the human body. This joint is a complex synovial joint that allows a wide range of movement. The two articulations in this joint are the tibiofemoral joint and the patellofemoral joint. The knee joint is a weight-bearing joint and is mainly stabilized by four ligaments. These include anterior cruciate (ACL), posterior cruciate (PCL), medial collateral (MCL), and lateral collateral (LCL) ligaments. These ligaments provide static stability to the joint, whereas, muscles that attach to the knee joint provide dynamic stability. The knee joint employs several bursae or fluid-filled pockets to reduce friction between the joint surfaces during movement. Joint dislocation, inflammation, and ligamentous injury as common pathologies of the knee joint. 
Osteoarthritis-associated knee pain is a common complaint among older individuals, accounting for 16% of this population in the US. This has adverse effects on quality of life and hinders the routine activities of an individual. The knee pain may be acute, lasting lesser than six weeks, or chronic that has a duration of six and more weeks. 
Causes and Risk Factors of Knee Pain
Risk factors of knee pain include advanced age, obesity, previous trauma to the knee and associated structures, as well as knee-straining occupational or athletic activities. Muscle imbalances also increase the risk of knee pain. The knee pain may be precipitated by the psychological and emotional state of a person. Different causes of knee pain are listed below. [1, 3]
- Iliotibial band syndrome – the iliotibial band is a thick fibrous band that functions to stabilize the knee and hip joints. Iliotibial band syndrome is characterized by inflammation of this band and tenderness on the lateral part of the knee joint.
- Anterior cruciate ligament (ACL) injury – this is the most common ligamentous injury of the knee joint, characterized by a ‘popping’ sound.
- Posterior cruciate ligament (PCL) injury – commonly occurs when the bent knee hits the dashboard during vehicle accidents.
- Collateral ligament injuries – caused by the sideway knee injuries
- Meniscal tears – common injury among athletes caused by twisting of the knee while the foot remains fixed
- Bursitis – inflammation of the bursae
- Tendonitis – inflammation of the muscle tendons
- Osteoarthritis – wear and tear of the knee joint
- Rheumatoid arthritis – an autoimmune disease that causes the synovial membrane to become inflamed.
Clinical Features of Knee Pain
The common signs and symptoms of knee pain are as follows. 
- Inflammation of the knee joint that causes stiffness and swelling of the joint
- The joint is weak and unable to bear the body weight efficiently
- Weakness of the joint and surrounding structures
- A person suffering from knee pain is unable to straighten the lower limb at the knee joint
- The joint and surrounding area is warm and red
- Production of unusual sounds when moving the knee joint
Normal Healing Cycle
To identify and eliminate the root cause of the disease, it is important to acquire basic knowledge about the normal healing cycle. The normal healing cycle is comprised of three stages known as inflammation, proliferation, and maturation.
In this stage, the blood flows to the injured area increases, causing redness and warmth. Increased blood flow causes the fluid to leak out of the capillaries and accumulate in the affected area, giving rise to swelling. Inflammatory mediators are released by the injured and the inflammatory cells release cytokines that recruit the immune cells. These immune cells, including neutrophils and macrophages, are important for eliminating the substance or pathogen that elicits inflammation.
As indicated by the name, this stage is marked by the proliferation of different structures to form scar tissue to fill in the wound defect. This includes collagen production by the fibroblasts, formation of new blood vessels, extracellular matrix, and granulation tissue. Owing to excessive fibrosis during this stage, fascia restrictions and the formation of trigger points may also occur. It leads to muscle spasm on one side and causes wear and tear of the structures involved. This will limit the range of movement, cause excess damage due to the joint structures, and elicit pain.
This stage marks the resolution of the healing cycle. During this stage, the wound contracts, and the final scar tissue forms.
In individuals who suffer from chronic conditions, hormonal imbalances and nutrient deficiencies lead to an improper healing cycle. The affected site oscillates between the proliferation and inflammation stages as the body lacks nutrients to carry out a normal healing cycle. 
Knee Pain Treatments That Don’t Work
Following treatments are used to relieve knee pain, however, they do not make a significant difference to the healing cycle.
- Applying heat and ice
- Electric stimulation of the joint
- Foam roller
- Massaging of the joint
- Joint mobilization
- Stretching of the muscles
- Strength exercises in the inflammation stage
Effective Treatment for Knee Pain
To eliminate the root cause of the disease, one should target the initial two stages of the healing cycle simultaneously.
To regulate the inflammation stage, an individual should rest for almost 5-7 days and should not overwork the joint. Moreover, a person suffering from knee pain should consume an anti-inflammatory diet to prevent internal inflammation. This diet contains fruits, legumes, herbs and spices, phytochemicals, flavonoids, mono- and poly-unsaturated fatty acids such as omega-6 fatty acids. One should refrain from pro-inflammatory substances such as alcohol, refined sugars, and trans-fatty acids.  Apart from the dietary and lifestyle changes, MagnaHeal, a magnetic anti-inflammatory device, also yields better outcomes when used for knee pain. MagnaHeal 2 has a magnetic force length of 3 inches and penetrates deeper tissues to reduce severe inflammation.  Vitamins, minerals, and hormonal imbalances also lead to disruption of the normal healing cycle and give rise to chronic inflammation. AskASTR is a software program used to determine the nutrient deficiencies in an individual in a short time.
Similar to inflammation, the proliferation stage should also be regulated simultaneously. To release superficial scar tissue and trigger points that cause muscle imbalance and knee pain, the A3 Release Tool is used. A5 Release Tool is used for releasing deeper trigger points, scar tissue, and fascia restrictions (endomysium, perimysium, and epimysium). A1 Release Tool is used for superficial and aponeurotic fascia restrictions. Fascia comprises superficial and deep layers. The deep layer is further divided into aponeurosis, epimysium, perimysium, and endomysium. While releasing fascia restrictions, it is important to address both the superficial and deeper adhesions.
A summary of the treatment options for knee pain is given below.
- Adequate rest
- Inhibit repetitive motions that cause knee pain
- Wear knee pads while working
- Stabilize the knee muscles
- Inflammation stage (anti-inflammatory diet, restore nutrient deficiency, and MagnaHeal 2)
- Proliferation stage (A1, A3, and A5 Tools for scar tissue, fascia restrictions, and trigger points)
Knee pain can be a debilitating event for older individuals. It compromises mobility and deteriorates the quality of life. While knee pain arises due to age-related wear and tear of the joint, trauma is also a leading cause of knee pain. In order to provide effective pain relief, one should focus on mediating the healing cycle. Correcting the healing cycle is the key to alleviating pain and eliminating the root cause of knee pain.
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- Mat S, Kamaruzzaman SB, Chin AV, Tan MP. Impact of Knee Pain on Fear of Falling, Changes in Instrumental Activities of Daily Living, and Falls Among Malaysians Age 55 Years and Above. Front Public Health. 2020 Oct 14;8:571196. DOI: 10.3389/fpubh.2020.571196. PMID: 33163471; PMCID: PMC7591456.
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- Grubbs H, Manna B. Wound Physiology. [Updated 2021 Jun 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK518964/
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- Ross CL, Harrison BS. Effect of pulsed electromagnetic field on inflammatory pathway markers in RAW 264.7 murine macrophages. J Inflamm Res. 2013;6:45-51. DOI: 10.2147/JIR.S40269. Epub 2013 Mar 12. PMID: 23576877; PMCID: PMC3617815
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