Knee Arthritis

Definition

What is knee osteoarthritis?

Osteoarthritis of the knee joint (gonarthrosis) is a degenerative disease of the knee joint. The knee joint connects the upper and lower leg bones and the kneecap. Wherever the knee joint bones touch, these contact surfaces are covered with a layer of cartilage. Healthy cartilage has a very smooth sliding surface that enables low-friction movement in the joint. In osteoarthritis of the knee, the cartilage is partially damaged. Cartilage damage is divided into four stages:

• Stage/grade I: Soft cartilage
• Stage/grade II: Rough surface with cracks
• Stage/grade III: Deep tears in the cartilage that extend to the bone
• Stage/grade IV: Complete wear of the cartilage with exposed bone. This is also referred to as bony baldness.

Where does the pain from knee osteoarthritis come from

The intensity and frequency of pain in knee osteoarthritis (gonarthrosis) varies greatly from person to person. Often, the intensity and frequency of pain are also very variable in the person suffering from osteoarthritis of the knee. Many people wrongly assume that only the degraded cartilage causes the pain in osteoarthritis of the knee. The variability of osteoarthritis pain in the knee proves that it is not just the degraded cartilage or cartilage damage in the knee that causes the pain. If this were the case, the pain would be relatively constant over a certain period of time and would be felt with every movement of the knee joint. People suffering from osteoarthritis of the knee often report that they are completely pain-free within a very short period of time, and even experience severe pain around the knee joint. This pain variability proves that cartilage health and thickness should not be the sole basis for deciding on further measures. X-rays and other imaging procedures should therefore have no relevant influence on the assessment of the severity of osteoarthritis in the knee and knee joint osteoarthritis treatment. As with all structures in the body, cartilage also undergoes a continuous build-up and breakdown process. The aim in everyday life must now be to ensure that the degradation processes do not overlap the build-up processes. These processes are discussed in more detail on this page. The variability in the intensity and frequency of pain is partly due to the fact that the areas of knee arthrosis can vary. A distinction is made between the following areas:

• on the inside of the knee joint (medial)
• on the outside of the knee joint (lateral)
• under the kneecap (patellofemoral)

Conversely, the causes of pain in knee osteoarthritis are diverse, as different internal processes occur in the body during knee osteoarthritis. The most common processes are explained below:

• Cartilage degradation

  Articular cartilage acts as a shock absorber between the bones of the knee joint. If the cartilage gradually breaks down, additional pressure can be exerted on the periosteum. The periosteum is equipped with blood vessels and numerous nerves, which react to the pressure with corresponding pain. In contrast to the bone, the periosteum is very sensitive to pain.

• Joint inflammation (synovitis)

  Cartilage wear can trigger inflammatory processes in the synovial membrane (synovia). This inflammation leads to increased production of synovial fluid and can cause swelling, overheating and pain.

• Joint effusions

  The increased formation of joint fluid (effusion) as a reaction to cartilage degradation exerts additional pressure on the joint, which can cause pain and feelings of tension.

• Irritation of the surrounding tissue

  The changes in the joint also irritate surrounding structures such as ligaments, tendons, muscles and fascia. This irritation can also cause pain and increased joint stiffness, especially after long periods of rest or at the start of movements.

• Bone changes (osteophytes)

  As osteoarthritis progresses in the knee, bony growths, known as osteophytes, form on the edges of the joint. These bony outgrowths are not painful themselves, but can press on nerves or soft tissue, which leads to additional pain and restricted movement.

• Microcracks in the bone (subchondral changes)

  The increasing loss of cartilage also puts more strain on the underlying bone (subchondral bone). This can lead to small cracks, bone thickening or so-called "debris cysts", which also cause pain.

• Myofascial tension

  The musculoskeletal system senses the incorrect and excessive strain on the knee joint and tries to protect the joint and the cartilage by tensing the muscles and fasciae so that the knee can no longer be moved to the maximum possible extent. This tension in the myofascial structures can lead to pain during movement, as the muscles are working against this tension.

Causes of knee osteoarthritis

The causes of cartilage degeneration and the associated osteoarthritis pain in the knee are closely linked to modern lifestyles and changing environmental conditions. In the past, our ancestors had to move more holistically and significantly more in order to obtain food. Hunting, foraging for berries or farming are just a few examples. For long stretches, this movement was carried out barefoot and on natural ground. The surface of the ground and the extent of the movement meant, among other things, that the foot and leg muscles were well developed and naturally strained.
Lifestyle has changed considerably over the millennia. Modern civilization is often characterized by a lack of movement and a sedentary lifestyle. However, when we do move, it is on hard, flat floors such as concrete or asphalt and in immobile, supportive shoes due to the changed environmental conditions. Consequently, the altered quantity and quality of movement leads to physical adaptations. The effects of this on the development of osteoarthritis of the knee joint (gonarthrosis) are described below.

Lack of exercise and a sedentary lifestyle

The modern way of life, which is characterized by a lack of exercise and a sedentary lifestyle, places incorrect strain on the musculoskeletal system. The lack of exercise and sedentary lifestyle lead to physical adaptations that can cause the knee joint cartilage to break down. The following changes play a significant role in the development of osteoarthritis of the knee joint:

• Weakened muscles

  Lack of exercise and a sedentary lifestyle cause the essential muscles to atrophy. The foot and leg muscles play a crucial role in the health of the cartilage in the knee joint. On the one hand, functional foot muscles support the longitudinal arch of the foot, which is the first instance of reducing the force exerted on the knee and thus its cartilage when standing and walking. On the other hand, the foot and leg muscles ensure that the foot rolls naturally and thus protects against uncontrolled foot drop after heel strike. Due to uncontrolled rolling of the foot, the knee is hit with every step instead of being guided physiologically. This incorrect and excessive strain leads to overloading of the cartilage in the knee joint. The lower leg and thigh muscles stabilize the knee joint and keep it in the correct position. Active and tense muscles around the knee joint also protect the cartilage from the forces exerted during each individual movement. The importance of functioning muscles in the feet and legs is therefore essential for the health of the joint cartilage.

• Foot malpositions

  The weakened musculature can also lead to foot deformities. The muscles responsible are no longer able to support the longitudinal arch, which leads to flat feet. The collapse of the longitudinal arch deprives the foot of its shock-absorbing function when walking and standing. The force exerted is therefore transmitted directly to the knees and their cartilage via the feet with every step. The increased load can damage the cartilage over time, leading to osteoarthritis in the knee and knee pain.
  Furthermore, a bent foot and pronation and supination can shift the knee axis inwards or outwards, which leads to increased stress on the cartilage on the respective side. Prolonged one-sided strain can result in cartilage degradation in the knee joint.

• Restricted supply to the cartilage

  The cartilage in the knee is not supplied directly by blood vessels, but receives its nutrients from the synovial fluid that is pumped into the joint through movement. A lack of movement disrupts this process, which leads to an insufficient supply of nutrients and oxygen to the cartilage. This reduces the elasticity and resilience of the cartilage, increases friction and wear and tear and can lead to osteoarthritis of the knee in the long term.

• Fascia dysfunction

  The fasciae change their original structure and can become brittle if they are subjected to irregular and unphysiological stress. This causes the fascia network to lose its elasticity and leads to increased tension around the knee joint. The increased tension pushes the upper and lower leg bones closer together and brings the kneecap closer to the knee joint. This additional pressure from the closer bones wears down the cartilage layer excessively. This can lead to osteoarthritis in the knee joint. The altered fascia structure can also impair the mobility of the joint, causing it to stiffen. More on this in the following section.

• Joint stiffness

  Due to a lack of exercise and a sedentary lifestyle, the joints are not moved to the maximum possible range of motion. The result is a natural stiffening of the joints. Immobile joints, especially in and around the foot, prevent a natural rolling movement and thus increase the force exerted on the knee joint. In addition, the knee joint can also stiffen, which also increases the pressure in and around the knee. The cartilage is therefore misloaded and overloaded and can lead to osteoarthritis in the knee joint.

Hard, flat floors and stiff, restrictive footwear

Hard, flat floors and immobile, supportive shoes have a significant impact on the knee joints and can cause or exacerbate osteoarthritis of the knee. The following factors play a significant role in the development of osteoarthritis of the knee.

• Reduced shock absorption and increased force effect

  When walking on hard, flat floors and in immobile, supportive shoes, higher forces act on the musculoskeletal system, especially during heel strike. The firmness of industrial floors and the stiffness of conventional shoe soles prevent these forces from being absorbed, which leads to increased strain on the body. This increased force first hits the feet and is then transferred to the hips via the knees. The less well the feet can absorb the forces, the greater the strain on the hips. The cartilage in the hip joint is therefore subjected to greater stress with every step.
  
  The increased and early application of force during heel strike shortens the possible reaction time of the responsible muscles. If the muscles cannot tense in time, the corresponding joint is insufficiently stabilized, which leads to incorrect and excessive strain. Insufficient muscular tension in the feet results in uncontrolled folding of the midfoot after heel strike. This results in the so-called "hinged foot" and leads to an additional impact on the hip joint, which further damages the cartilage. The hip-stabilizing leg and pelvic muscles are also unable to react quickly enough due to the early and increased force. The reduced muscular tension leads to an unstable hip joint, which increases the strain on the cartilage and can lead to osteoarthritis in the hip in the long term.

• Limited foot function and muscle weakness

  The human knee joint is part of a complex system that coordinates movement from the foot to the leg to the hip. Flexible, natural movements are crucial in order to distribute the load evenly and minimize pressure on the knee. Inflexible, supportive shoes can significantly impair this natural movement. Such shoes artificially stabilize the foot and restrict the mobility of the ankles. As a result, important muscles and tendons that help to stabilize the leg are less activated. This can lead to increased strain on the knee joints. Long-term overuse promotes the breakdown of cartilage tissue and leads to osteoarthritis in the knee joint.
  
  Studies show that immobile, supportive shoes are often associated with reduced muscle activity in the calf and thigh muscles. However, these muscles play a crucial role in relieving pressure on the knee joint. Weakness in these muscle groups increases the risk of incorrect loading of the knee, which accelerates the wear and tear of the cartilage.

• Unnatural sequence of movements

  Natural movement sequences are designed to react dynamically to changing surfaces. Hard, flat floors and immobile, supportive shoes make a physiological sequence of movements much more difficult. On the one hand, the lack of muscle activation during heel strike causes the foot to fold downwards in an uncontrolled manner. The folding foot and its consequences for the knee joint were described in the previous section. On the other hand, the hardness and inflexibility of industrial floors and the stiffness of conventional shoe soles prevent the foot from rolling naturally. Due to the lack of rolling, the knee joint is not moved through its maximum range of motion, but is loaded in the same area with every step. On the one hand, this leads to certain structures being overloaded and others underloaded. In the case of articular cartilage, the overstressed areas lead to excessive degradation and thus accelerate osteoarthritis in the knee joint. Those areas of the cartilage that are not stressed can become brittle and lose their elasticity and thus their cushioning function. Furthermore, immobile, supportive shoes reduce the sensory feedback from the foot, which leads to a reduction in the exchange of information and therefore a reduction in adaptability. This results in a monotonous load, which is particularly harmful to the knee joint. The lack of variation and constant pressure on certain parts of the knee can cause microtraumas in the joint, which can develop into osteoarthritis of the knee over time.

Symptoms of knee osteoarthritis

It is important to note that the following are the most common symptoms of knee osteoarthritis (gonarthrosis). However, the list of knee osteoarthritis symptoms is not complete and exhaustive. Atypical knee osteoarthritis symptoms are also possible and are not listed here. Knee osteoarthritis symptoms often depend on various factors such as pain perception, cause of the injury, degree of injury, physical constitution, etc. A doctor should be consulted in order to obtain a clear diagnosis.

• Pain in the knee joint, which is initially load-dependent (e.g. when walking, climbing stairs) and later also occurs at rest or at night.
• Joint stiffness, which is particularly pronounced after long periods of rest (e.g. in the morning, so-called "start-up pain").
• Restricted mobility with difficulty bending or extending the knee. Restrictions in everyday movements, e.g. squatting or kneeling.
• Swelling and inflammation in the knee joint. Inflammation can be accompanied by localized overheating in the knee.
• With substantial cartilage wear, the bones rubbing against each other can result in crackling or popping sounds.
• Feeling of instability in the knee
• Lack of stability under load.
• Muscle weakness in the surrounding thigh muscles that stabilise the knee.
• Misalignment of the knee with development of knock knees or bow legs due to uneven
• Weather-dependent knee pain in osteoarthritis. Pain and stiffness can increase in damp or cold weather.
• Varying sensation of pain: From no pain to extreme pain, the pain can vary accordingly in the same person within one day. This is a strong indication that it is not the degenerated cartilage but the myofascial structures that are causing the pain. Reason: Cartilage damage is consistent, but tension and blockages are not.

Help with knee osteoarthritis - Conventional therapy

There are several approaches to treating knee osteoarthritis pain. Some knee osteoarthritis therapies are listed below. The list of these therapies is not exhaustive. Various measures can also be combined to treat knee osteoarthritis. A medical consultation is recommended to determine the appropriate therapy for osteoarthritis of the knee.

• Physiotherapy: Special knee osteoarthritis exercises and forms of therapy are used to improve mobility, strengthen the muscles and relieve the joint.
• Exercise therapy: Gentle training (e.g. swimming, cycling or yoga) promotes mobility and musculature without overloading. It also promotes blood circulation, which is useful when treating osteoarthritis of the knee.
• Weight reduction: Relief for the knee joints by reducing body weight and thus reduced pressure on the joints, less pain and slower cartilage degradation.
• Orthopedic devices: braces or orthoses to support and stabilize the knee joint. Shoe inserts to correct misalignments and relieve specific joint areas.
• Dietary change: An anti-inflammatory diet to reduce systemic inflammation around the knee joint as an appropriate treatment for knee osteoarthritis.
• Acupuncture: Relieving pain through the stimulation of designated points.
• Heat or cold applications: Heat to relax tense structures, cold to relieve inflammation. The appropriate temperature must be tested during knee osteoarthritis treatment.
• Magnetic field or electrotherapy: stimulation of blood circulation and pain relief.
• Medication therapy: Pain relievers and anti-inflammatory drugs. Cartilage-regenerating drugs for cartilage damage.
• Joint injections: Hyaluronic acid to improve joint lubrication and relieve pain. Cortisone to reduce inflammation in acute flare-ups and relieve pain in knee osteoarthritis.
• Autologous blood therapy: This method uses the healing properties of the body's own blood to regenerate joint cartilage and relieve knee osteoarthritis pain.
• Knee joint arthrosis surgery: arthroscopy with minimally invasive cleaning of the joint, e.g. removal of cartilage remnants. Osteotomy to correct misalignments through bone cuts. Knee prosthesis (partial or full prosthesis) with replacement of the knee joint in cases of very advanced osteoarthritis.

What helps with hip osteoarthritis? the kybun working principle

Kybun products aim to eliminate the health-damaging effects of hard, flat floors and immobile, supportive shoes and actively tackle the lack of exercise and sedentary lifestyle. The elastic, springy properties of kybun products relieve and activate the musculoskeletal system. The relief ensures that the load on the knee joint cartilage is reduced as a first step. Activation is intended to tackle the causes of osteoarthritis of the knee so that knee pain caused by osteoarthritis becomes a thing of the past in the long term. This makes kybun shoes ideal for knee osteoarthritis, as they help treat knee osteoarthritis through the following modes of action:

• Muscle activation and stabilization of the knee joint

  When walking in kybun shoes, the heels can sink deep into the elastic, springy material thanks to the compression capacity of the soles. By sinking in, the load is built up slowly and in a controlled manner, which gives the body more time to tense the relevant muscles. The tensed leg muscles stabilize the knee joint and the cartilage is naturally stressed. When walking on hard, flat floors and in immobile, supportive shoes, the load is applied to the feet without cushioning. Due to the associated increased force and reduced reaction time, the muscles responsible cannot tense up in time. The lack of muscle tension results in insufficient stabilization of the knee joint and therefore incorrect and excessive strain on the cartilage.

• Reduction of the force exerted by hard, flat floors due to damping effect

  When the heel strikes the ground in kybun shoes, the elastic-spring material is compressed. The compression capacity of the kybun sole allows the rear foot to sink deep into the elastic-spring material when the heel strikes the ground. This slow and controlled sinking reduces the force and therefore the load on the knee joint and its cartilage. Similar to an airbag in a car, the cushioning effect of the kybun sole helps to minimize the impact of force.

Furthermore, as the heel slowly sinks into the elastic, springy material, the body has more time to tense the relevant muscle groups. The improved basic tension in the muscles stabilises the individual joints and thus reduces the force exerted on the spine and surrounding structures.

• Activates and strengthens the muscles thanks to its elastic and springy properties

  When walking and standing on the elastic, springy kybun surface, the body must constantly make small compensatory movements to maintain balance. The deliberate instability of kybun products challenges the balance system and specifically activates the stabilizing deep muscles, which are responsible for stability and posture. This leads to the knee joint being better stabilized and thus protected by the surrounding muscles. At the same time, coordination skills are trained as the interaction between the nervous system and muscles is improved. This leads to an improvement in body awareness and the precision of each individual movement.

Equilibrium and EMG

The ability to maintain balance was measured with a force plate by moving the body's center of gravity from front to back (ant-post) and sideways (med-lat) when standing. At the same time, muscular activity was recorded using electromyography (EMG).

By activating and strengthening the foot muscles, foot misalignments such as splayfoot, flat foot or fallen arches, which are often caused by muscular deficits, can be counteracted. As an intact longitudinal arch reduces the forces generated during heel strike, the individual vertebrae and soft tissue are also relieved. As the foot is also prevented from bending inwards or outwards, the leg axis remains in its physiological position and the back and adjacent structures are protected from additional incorrect and excessive strain. The slow and controlled sinking of the heel into the elastic, springy material creates myofascial pretension in the muscles involved. This pretension and the improved muscular activity allow the spine to be stabilised and guided at an early stage, which also reduces the force exerted on the back and the surrounding soft tissue.

• Natural foot roll and increased range of motion thanks to the rebound effect

Thanks to the elastic-springy kybun shoes with the rebound effect and the associated muscular pre-tensioning and reduced acceleration, the foot can be set down in a controlled manner at heel strike. This prevents the cartilage-degrading folding foot, which hits the knee joint with every step. In addition, active rolling on the elastic, springy kybun material utilizes the entire range of movement of the foot. The movement sequence begins with the heel touching the ground and ends with the toes pushing off. By using the full range of movement in the feet, more movement is automatically generated in the knee joints. As a result, the knee joint is not always moved in the same range, which promotes cartilage degradation, but is used over the entire range of motion. The result is a reduction in the punctual load intensity. Furthermore, several studies have shown that cartilage can be rebuilt through natural and physiological loading. By using the full range of motion, the knee joint becomes or remains mobile and is protected from tension and blockages. This additional movement with a natural and physiological gait can activate and strengthen the muscles and promote blood circulation, which also has a positive effect on osteoarthritis of the knee.

• Improved circulation through increased movement activity

  The knee joint also requires numerous nutrients to nourish, maintain and regenerate the cartilage. These nutrients are transported to the corresponding tissue via the blood and synovial fluid. In addition, anti-inflammatory substances are transported to the knee joint via the blood, while harmful and inflammation-promoting messenger substances are transported away. This constant exchange of fluids thus supplies the cartilage and keeps it elastic and resistant. The elastic, springy kybun materials promote movement and thus activate the muscles around the knee joint. This increases blood circulation, which in turn promotes the benefits mentioned above.
  

• Promoting physical activity and reducing sedentary behavior

  The elastic, springy kybun products promote the joy of movement, as walking and standing on the unique material relieves pressure on the knee joints. The movement activates and strengthens the muscles and promotes blood circulation. The benefits of these two processes have already been described in the previous sections. As the use of kybun products can also reduce the duration of sedentary activity, harmful shortening and blockages of the myofascial structures can be avoided. Increased walking and standing stretches and lengthens the often shortened hip flexor muscles and the posterior chain of calf and thigh muscles, which has a positive effect on the angular position of the knee joint and the pressure on the knee joint cartilage.
  

• Care and protection of the facia

  The fasciae stabilize the knee joint and distribute the load evenly with every single step, which protects against cartilage wear. Healthy and functional fasciae are elastic and therefore free from adhesions and tension. Elastic fascia promotes the mobility of the knee joint and supports good blood circulation, which is important for the nutrient supply and regeneration of the cartilage. Thanks to the kybun shoes, a natural sequence of movements is made possible, which keeps the fasciae elastic.
  

• Optimized pressure distribution

  When walking and standing in kybun shoes, the entire sole of the foot is surrounded by the elastic, springy material. This leads to optimized pressure distribution in the feet. As a result, the punctual pressure on the knee joints and their cartilage can be reduced. In addition, the constant light movement on the kybun Joya products increases the load-bearing surface, which can also reduce pressure points. This can protect the cartilage from injury and wear and tear.

Application tips for knee osteoarthritis

Before you wear kybun shoes for the first time, you should consider a few tips on how to use them. Correct use can help to alleviate knee osteoarthritis pain. Osteoarthritis in the knee joint can also be treated with targeted knee osteoarthritis therapy, which is explained in the next section.

• To begin with, only wear the kybun shoes for as long as your body allows. Take breaks from wearing them if the knee pain caused by osteoarthritis increases or the musculoskeletal system becomes tired. Knee joint arthrosis treatment takes time. The activating properties of kybun products train the muscles, which can lead to so-called initial reactions, especially at the beginning.
  
• Press your heel slowly and in a controlled manner into the elastic, springy material so that the knee joint is relieved. Try to find a load point at which the pain in the knee joint is reduced or does not occur. At the beginning, make sure that you do not roll too much over your heels.
  
• Take small, controlled steps at the beginning, reducing the amount of rolling over the forefoot so that less movement is generated in the knee joint. Increase the range of motion of your feet over time, if possible.
  
• Try the following exercises to boost the effectiveness of kybun shoes and increase the chances of recovery. These are intended as a complementary therapy for back pain and should form part of the treatment for back pain.

Helpful exercises for knee osteoarthritis

To maximize the effectiveness of kybun shoes and enhance the probability of alleviating knee pain, we advise engaging in the following exercises for knee joint osteoarthritis. The exercise list is not comprehensive and can be supplemented with more exercises. The fundamental principle for all exercises is that the knee joint pain should not worsen. If any exercise aggravates the osteoarthritis pain in the knee, it should be ceased. Pain relief and soothing sensations outside the knee joint pain point (e.g., in the thigh) are desirable.

The exercises are divided into the following areas: "Correct walking in kybun shoes", "Muscle length training", "Fascia rolling" and "Strengthening". Ideally, the different areas should be used as complementary therapy for knee osteoarthritis.

Walking the right way in kybun shoes

The quality of each individual step is crucial in the treatment of osteoarthritis of the knee in order to reduce knee pain caused by osteoarthritis and to eliminate incorrect and excessive strain. The kybun shoes therefore offer ideal therapy for osteoarthritis of the knee.

Controlled heel strike

• Press the heel carefully and in a controlled manner into the elastic, springy material to determine the load strength and load point without causing pain in the knee joint.
• Controlled foot position so that the foot does not tilt inwards or outwards. This keeps the knee joint in a straight position.
• Lower the midfoot and forefoot slowly and in a controlled manner so that the knee joint is not hit.
• Slow exercises help to rebuild the stabilising muscles around the knee joint.

Quick step frequency

• Movement sequence identical to exercise 1.
• Now incorporate short steps with a high step frequency that lead to movement in the hip joint. However, always use the full range of motion of the feet.
• If you have pain in the hip joint, increase the stride length and reduce the frequency.
• Important! Maintain an upright posture when standing and walking. Do this consciously every day when using kybun products.