Baker’s Cyst

Author: K. Zbinden

Definition

What is a Baker’s cyst?

A Baker’s cyst is a fluid-filled bulge in the hollow of the knee, i.e., at the back of the knee. It is also called a popliteal cyst. Simply put, it is a cyst in the knee caused by excess synovial fluid. The knee joint is surrounded by a joint capsule that contains synovial fluid. This fluid ensures that the knee can move smoothly. However, if the knee is irritated or overloaded, it produces more fluid—commonly referred to as “water on the knee.” If the pressure in the knee joint increases, the fluid looks for an outlet.
This outlet is often located in the hollow of the knee. There, the joint capsule bulges backward and a knee cyst develops—the Baker’s cyst. You can imagine it like a small, fluid-filled balloon that forms behind the knee.

It is important to know that a Baker’s cyst in the knee is not a disease in its own right. It almost always develops as a result of an underlying change in the knee. In a way, the knee tries to reduce the increased pressure in the joint by releasing fluid into the hollow of the knee. Depending on its size, a Baker’s cyst in the hollow of the knee can go unnoticed for a long time or cause symptoms. In rare cases, the Baker’s cyst can rupture. When a Baker’s cyst ruptures, the fluid leaks into the surrounding tissue, which can lead to sudden swelling and pain in the lower leg. This is also referred to as a ruptured Baker’s cyst.

Causes of a Baker’s cyst

The development of a Baker’s cyst is closely linked to changes in the knee joint. A Baker’s cyst is usually the result of excess synovial fluid being forced into the hollow of the knee. This fluid often occurs due to meniscal injuries, cartilage damage, knee osteoarthritis, or inflammatory processes. Repeated micro-injuries or overuse of the knee can also promote the formation of a Baker’s cyst in the hollow of the knee.
In the past, the human musculoskeletal system was challenged much more. Our ancestors moved a lot and in a holistic way. Movement back then took place barefoot on natural ground. The quality and quantity of movement led to strong foot and leg muscles that stabilized the knee, distributed synovial fluid evenly, and relieved the joint. Today, lack of exercise, long periods of sitting, and hard, flat floors are the norm. These factors promote faulty loading, overuse, and the accumulation of synovial fluid—making it possible for a Baker’s cyst to develop in the knee.

Lack of exercise and a sedentary lifestyle

Due to modern lifestyles—often characterized by little movement and predominantly sedentary daily routines—the knee joint is increasingly misloaded and underloaded. This lack of natural movement can promote the formation of a Baker’s cyst or worsen existing Baker’s cyst symptoms. The muscles around the knee become weaker, circulation decreases, and joint mechanics can become imbalanced. All of these changes play a central role in the development and progression of a Baker’s cyst.

• ◉ Weakened muscles and muscular imbalances

  Long periods of sitting and lack of movement lead to weakening of the thigh and lower-leg muscles that normally stabilize the knee joint. Weak muscles cannot adequately absorb forces during walking and standing, increasing pressure in the knee. This can cause synovial fluid to pool in the hollow of the knee and a knee cyst to form.

• ◉ Poor posture and overloading of the knee joint

  Due to insufficient muscle control and weakness, slight axis deviations or malalignments of the knee may occur. As a result, the joint is loaded unevenly. This overload leads to increased production of synovial fluid, which accumulates in the hollow of the knee and enlarges the Baker’s cyst.

• ◉ Restricted circulation

  Cartilage and joint structures are supplied via synovial fluid. Lack of movement reduces circulation, meaning the cartilage receives fewer nutrients and less oxygen. This weakens the tissue and promotes fluid accumulation in the hollow of the knee.

• ◉ Foot misalignments

  Weak muscles in the foot and lower leg can lead to fallen arches, pronation, or flat feet. These misalignments change the load lines in the knee and increase pressure in certain areas. This increases the likelihood that synovial fluid will be pushed into the hollow of the knee and a Baker’s cyst develops in the leg.

• ◉ Shortened and tight structures

  One-sided strain and lack of movement lead to shortened muscles and tendons around the knee joint, which can restrict the knee’s range of motion and pull the lower leg and thigh closer together. This tension increases pressure in the knee joint and promotes the formation of a Baker’s cyst.

• ◉ Fascia dysfunction

  Fascia that surrounds muscles and tendons loses elasticity when there is a lack of movement. Adhesive and tight fascia creates additional tension in the knee, increasing pressure on the joint capsule and potentially promoting a Baker’s cyst in the knee.

• ◉ Joint stiffness

  Limited movement of the knee joints can lead to natural stiffening and reduces the natural distribution of synovial fluid. Stiff joints increase pressure and prevent the fluid from regularly flowing back into the joint. This promotes the accumulation of synovial fluid in the hollow of the knee and supports the growth of a Baker’s cyst.

Hard, flat floors and rigid, supportive shoes

Hard, flat floors and rigid, supportive shoes have a significant impact on the knee joint and can promote the development or worsening of a Baker’s cyst. One-sided loading, lack of cushioning, and restricted foot mobility are transferred directly to the knee. This can overload the hamstring tendons, joint capsule, and bursae, thereby promoting the formation of a knee cyst. The following factors play a central role in the development and deterioration of a Baker’s cyst:

• ◉ Reduced shock absorption and increased force impact

  Walking and standing on hard floors increases the forces acting on the knee. Without sufficient cushioning, the load is transferred directly to the joint. This overload irritates the joint capsule, increases the production of synovial fluid, and thus promotes the formation of a Baker’s cyst in the knee.

• ◉ Restricted foot function and muscle weakening

  Supportive shoes reduce the natural mobility of the feet. As a result, muscles and tendons are activated less, even though they normally stabilize the knee. Weak muscles lead to higher pressure peaks in the knee, making it easier for synovial fluid to pool in the hollow of the knee.

• ◉ Altered gait and roll-off movement

  Rigid shoes and hard floors prevent a natural roll-off movement of the foot. As a result, the knee is not moved evenly but loaded in specific spots. Due to the restricted roll-off, certain structures are constantly overused while others are underused and gradually regress over time. This altered gait and roll-off movement leads to local overload of the joint capsule and can promote the accumulation of synovial fluid in the hollow of the knee, which can result in a knee cyst.

Baker’s cyst symptoms

The symptoms of a Baker’s cyst often depend on various factors such as pain perception, cyst size, duration of symptoms, underlying knee conditions, and physical constitution. Often, the characteristic Baker’s cyst symptoms indicate that a cyst is present in the hollow of the knee. To obtain a clear diagnosis, a physician should be consulted. Ultrasound or MRI is often used for diagnosis, as only these examinations can reliably visualize a Baker’s cyst in the knee. Below are the most common symptoms of a Baker’s cyst. It is important to note that atypical symptoms can also occur, and the list is not exhaustive.

• ◉ Swelling in the hollow of the knee: A noticeable bulge at the back of the knee is often the first visible sign of a Baker’s cyst.
• ◉ Pain in the hollow of the knee: Dull or pulling pain in the hollow of the knee often occurs when straightening or bending the knee.
• ◉ Restricted movement: The knee cannot be fully straightened or bent, especially after prolonged rest or exertion.
• ◉ Feeling of tightness: Those affected report a sensation of pressure or tightness in the hollow of the knee that increases with activity.
• ◉ Warmth or redness: The skin over the cyst may feel slightly warm or appear reddened, especially in inflammatory processes.
• ◉ Fluid-filled swelling: A Baker’s cyst in the knee feels soft or elastic because it is filled with synovial fluid.
• ◉ Cracking or grinding: When moving the knee, audible cracking or grinding may occur if the cyst presses on surrounding structures.
• ◉ Radiating pain: Sometimes the pain radiates along the back of the lower leg down to the calf.
• ◉ Reduced stability: The knee may feel unstable, especially when climbing stairs or standing up from sitting.
• ◉ Swelling of the lower leg: With larger cysts, fluid can run into the lower leg, causing swelling in the leg.
• ◉ Feeling of “pressure in the knee”: Baker’s cyst experience reports show that sufferers feel a persistent sensation of tightness or pressure that increases with prolonged sitting.
• ◉ Back pain or hip discomfort: In rare cases, abnormal loading due to the Baker’s cyst can cause secondary symptoms in the leg or back.
• ◉ Fatigue or tiredness when walking: The knee joint is more strained by the cyst, making walking feel more tiring.
• ◉ Redness and warmth after exertion: Sporting activities or prolonged standing can worsen the symptoms.
• ◉ Sudden onset of pain with a Baker’s cyst rupture: If the Baker’s cyst has ruptured, acute, stabbing pain occurs, often accompanied by swelling in the lower leg and bruising.
• ◉ Sensation of fluid movement: Some people feel “flowing” of synovial fluid in the hollow of the knee when moving.

Note:

A Baker’s cyst can also be asymptomatic, especially if it is small. In these cases, the cyst often remains undetected until it is seen during an examination. If pain increases, swelling becomes severe, or a sudden Baker’s cyst rupture occurs, medical help should be sought immediately.

Conventional therapy – What helps with a Baker’s cyst

There are various conventional approaches to treating a Baker’s cyst. The goal is to reduce swelling in the hollow of the knee, pain, and movement restrictions, and to avoid possible complications of a ruptured Baker’s cyst. Some treatment options for a knee cyst are outlined below. The list is not exhaustive. Often, several measures are combined to relieve symptoms. A medical consultation is recommended to determine the appropriate Baker’s cyst therapy.

• ◉ Physiotherapy: Targeted mobility and stretching exercises improve knee joint mobility, promote the drainage of synovial fluid, and strengthen the muscles around the knee. This reduces strain on the hollow of the knee and alleviates Baker’s cyst symptoms.
• ◉ Manual lymphatic drainage: For a Baker’s cyst, manual lymphatic drainage can reduce swelling of the knee cyst, promote the drainage of synovial fluid, and ease discomfort in the hollow of the knee.
• ◉ Cold or heat applications: Cooling reduces acute pain and inflammation, while heat improves circulation and relaxes muscles.
• ◉ Compression / knee braces: Braces or elastic compression sleeves stabilize the knee, relieve the Baker’s cyst, and reduce the feeling of tightness in the hollow of the knee.
• ◉ Medical training therapy / MTT: Under guidance, strength, mobility, and stability of the leg are built up in a targeted way. Strong thigh and calf muscles support the knee and can help prevent the development of a Baker’s cyst in cases of joint problems.
• ◉ Pain and anti-inflammatory medication: Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or diclofenac can reduce inflammation and pain in the hollow of the knee. For more severe symptoms, cortisone preparations prescribed by a physician may be used.
• ◉ Aspiration of the Baker’s cyst: In particularly painful or severely swollen Baker’s cysts, the doctor can aspirate the cyst to remove synovial fluid and reduce pressure in the hollow of the knee. In some cases, cortisone may be injected into the joint to relieve inflammation.
• ◉ Occupational therapy / posture training: Occupational therapists can optimize everyday movements, help avoid improper loading of the knee, and thereby reduce Baker’s cyst symptoms.
• ◉ Orthopedic aids: Insoles or shoe modifications can correct malalignments that additionally stress the knee and increase the risk of Baker’s cyst symptoms.
• ◉ Weight reduction: Excess weight increases the load on the knee joint and can worsen a Baker’s cyst in the knee. Healthy weight loss relieves the joint in the long term.
• ◉ Rest and targeted activity breaks: Short-term relief of the knee reduces pain and swelling. Afterwards, movement should be increased slowly to promote knee joint function.
• ◉ Pain therapy / physical measures: In acute pain, anti-inflammatory ointments, taping, or ultrasound therapy can relieve symptoms.
• ◉ Surgical procedures: If conservative measures have no effect or the Baker’s cyst repeatedly swells severely, surgical removal of the cyst may be necessary. The aim is complete reduction of the cyst and restoration of mobility.
• ◉ Regular monitoring: If Baker’s cysts are known, swelling and symptoms should be checked regularly by a doctor to detect complications such as a Baker’s cyst rupture at an early stage.
• ◉ Education and prevention: Those affected learn which movements place less strain on the knee and how to prevent new Baker’s cysts from forming.

Many conventional measures mainly treat the symptoms of the Baker’s cyst. The underlying cause of the Baker’s cyst, such as joint inflammation or meniscus damage, must also be clarified medically to avoid long-term problems. The kybun mode of action offers an additional option to relieve and stabilize the knee joints and to actively support the musculature.

kybun mode of action – What helps with a Baker’s cyst

kybun products aim to reduce the harmful health effects of hard, flat floors and rigid, supportive shoes, while also actively addressing lack of exercise and a sedentary lifestyle. Thanks to the elastic, springy properties of kybun products, the musculoskeletal system is relieved on the one hand and activated on the other.
Relief can help, as a first step, to reduce pain and sensations of pressure in the hollow of the knee, which often occur with a Baker’s cyst. Through activation, underlying causes of a Baker’s cyst—such as improper loading of the knee joint, muscular imbalances, and limited mobility—are intended to be addressed so that symptoms decrease in the long term. Therefore, kybun products are suitable for a Baker’s cyst because, through the following modes of action, they can provide supportive help in treating a Baker’s cyst:

• ◉ Muscle activation and stabilization of the knee joint

  When walking in kybun shoes, the heels can sink deeply into the elastic, springy material thanks to the compressibility of the soles. This allows the load to build up slowly and in a controlled manner. This time delay gives the muscles the opportunity to tense in time and actively stabilize the knee joint.
  Well-coordinated and strong leg muscles reduce uncontrolled movements in the knee that can lead to increased production of synovial fluid—a key factor in the development of a Baker’s cyst in the hollow of the knee. Stable knee guidance therefore indirectly relieves the hollow of the knee and can reduce pressure on an existing cyst.

• ◉ Reduction of force impact from hard, flat floors through the cushioning effect

  When the heel strikes hard, flat floors, the elastic, springy kybun material is compressed. Similar to an airbag in a car, the cushioning property of the kybun sole significantly reduces the acting force. This decreases the mechanical load in the knee joint, which can reduce irritation in the joint. Less irritation often also means less formation of excess synovial fluid—an important aspect in relieving a Baker’s cyst.

• ◉ Activation and strengthening of the muscles through elastic, springy properties

  Standing and walking on the elastic, springy kybun surface challenges balance and continuously activates the stabilizing deep muscles. These muscles play a crucial role in guiding and securing the knee joint. With improved muscular control, the knee is not “guided” passively but stabilized actively. This can reduce faulty loading that would otherwise lead to overloading of joint structures and irritation of the knee joint capsule—processes that can encourage the development or progression of a knee cyst.

Balance and EMG

Balance ability was measured with a force plate by tracking the movement of the body’s center of mass from front to back (ant-post) and side to side (med-lat) while standing. In parallel, electromyography (EMG) recorded muscular activity.

• ◉ Natural foot roll and improved knee mobility thanks to the rebound effect

  Thanks to the elastic, springy kybun sole with rebound effect, the foot is set down in a controlled manner after heel strike because the foot muscles can stabilize it. The uncontrolled “flopping” of the foot—which otherwise causes jerky loads in the knee—is significantly reduced. The energy stored in the sole is used for forward movement, creating an active and gentle roll-off motion.
  Through this natural roll-off, the knee joint moves more evenly and through a greater range of motion. Even movement of the knee joint can regulate pressure within the joint and thus reduce the accumulation of synovial fluid. This has a positive effect on tightness and pressure sensations in the hollow of the knee in the case of a Baker’s cyst.

• ◉ Improved circulation through increased activity

  Adequate circulation is crucial for removing pro-inflammatory substances and excess synovial fluid. Due to their activating properties, kybun products promote everyday movement and thereby increase muscle activity around the knee joint. The resulting improved circulation supports metabolism in the knee joint and the hollow of the knee. This can help reduce swelling and support regeneration of irritated structures in a Baker’s cyst.

• ◉ Promoting movement and reducing sitting time

  The elastic, springy kybun products increase enjoyment of movement because they relieve the knee joint while walking and standing. At the same time, they reduce sedentary behavior, which often leads to reduced circulation and joint stiffness. More everyday movement supports the knee’s natural joint function, improves mobility, and can reduce pressure build-up in the knee joint and the hollow of the knee—a key point in the long-term relief of a Baker’s cyst.

• ◉ Care and protection of the fascia

  Fascia around the knee and the hollow of the knee plays an important role in pressure distribution and guiding movement. Due to monotonous loads and lack of movement, these structures can harden or become adhesive. The natural movement sequence in kybun products supports fascia elasticity, improves gliding of tissue layers, and can reduce tension in the hollow of the knee. This relieves the region where a Baker’s cyst forms.

• ◉ Optimized pressure distribution

  Thanks to the elastic, springy material, loads while walking and standing are distributed across the entire sole of the foot. This optimized pressure distribution reduces peak loads that would otherwise travel along the leg axis up to the knee. More even loading of the knee joint can reduce irritation of the joint capsule and thereby indirectly reduce pressure and tightness in the hollow of the knee in the case of a Baker’s cyst.

Tips for using kybun with a Baker’s cyst

Before using kybun shoes for the first time, you should follow a few usage tips. Correct use can help relieve swelling and pain in the hollow of the knee caused by a Baker’s cyst. In addition, you should treat a Baker’s cyst with targeted therapies and exercises, which are explained in the next section.

• ◉ At the beginning, wear kybun shoes only as long as your body allows. Especially with a knee cyst, you may initially experience a feeling of tightness or slight fatigue. Take deliberate breaks from wearing them if knee pain, pressure in the hollow of the knee, or increased swelling occurs. Treating a Baker’s cyst takes time, as muscles, fascia, and synovial fluid need to adapt gradually. Initial reactions are possible and are usually temporary.
  
• ◉ Place the heel slowly and in a controlled manner onto the elastic, springy material. Press the heel consciously and calmly into the kybun sole to reduce strain on the knee joint and the hollow of the knee. The goal is to find a load point at which knee pain or the tightness sensation of the Baker’s cyst decreases or does not occur. Avoid jerky movements and hard heel strikes, as this can increase pressure in the knee.
  
• ◉ At the beginning, walk with small, controlled steps. Keep steps rather short and initially reduce the strong roll-off over the forefoot. This doses movement in the knee and limits pressure on the Baker’s cyst in the hollow of the knee. As you become accustomed, you can gradually increase the range of motion, provided that swelling in the hollow of the knee and symptoms allow it.
  
• ◉ Focus on regular, gentle movement instead of prolonged immobilization. Short periods of walking and standing in everyday life promote circulation and support the removal of excess synovial fluid (“water on the knee”). This can help reduce swelling of the Baker’s cyst. However, avoid long periods of standing without movement as well as abrupt changes in load.
  
• ◉ Complement use with targeted exercises. Simple, gentle exercises can enhance the effect of kybun products and positively influence the causes of the Baker’s cyst.

What to do for a Baker’s cyst? Helpful exercises

To increase the effectiveness of kybun shoes or the kybun mat, we recommend performing the following exercises to reduce swelling of the Baker’s cyst and to decrease recurrence. The selection of exercises is not exhaustive and can be complemented by additional therapies for treating a Baker’s cyst. As a general rule for all exercises: pain or swelling around the knee and in the hollow of the knee must not increase. If any exercise worsens symptoms, it must be stopped. Pleasant, light stretches or movements, however, are desired.

The exercises are divided into the following areas: “Proper walking in kybun shoes,” “muscle length training,” “fascia training,” and “strengthening.” Ideally, the different areas are used as complementary Baker’s cyst therapy to promote mobility, circulation, and strengthening of the knee joint.

Proper walking in kybun shoes with a Baker’s cyst

The quality of each individual step is crucial in treating a Baker’s cyst to reduce pressure in the knee joint and in the hollow of the knee. The goal is to minimize the formation of excess synovial fluid, promote circulation, and gently activate surrounding structures. kybun shoes provide ideal support for this.

Controlled heel strike

• ◉ Press the heel slowly and in a controlled manner into the elastic, springy material to reduce pressure on the knee joint and the Baker’s cyst in the hollow of the knee.
• ◉ Pay attention to a stable foot axis so the foot does not tip inward or outward. This achieves an even load on the knee joint.
• ◉ Set down the midfoot and forefoot calmly and in a controlled manner to avoid jerky peak loads in the knee.
• ◉ Slow, conscious steps promote activation of the joint-stabilizing muscles without additionally irritating the knee cyst.

Controlled roll-off

• ◉ Gentle roll-off over the forefoot without actively and forcefully pushing off with the toes.
• ◉ The stronger the roll-off, the higher the pressure in the knee joint and in the hollow of the knee. With existing swelling in the hollow of the knee, the range of motion should therefore be kept moderate.
• ◉ Explore the pain-free range of motion of the feet and slowly increase it, provided there is no increase in pressure or tightness.

Muscle length training

Shortened and tight muscles around the knee, thigh, and calf can increase pressure in the knee joint and thus promote the causes of a Baker’s cyst. Regular muscle length training helps reduce tension and improve fluid drainage from the hollow of the knee.

Calf muscles

• ◉ Starting position in a lunge.
• ◉ Back foot in neutral position (no external or internal rotation).
• ◉ Back heel remains in contact with the ground and should not be lifted.
• ◉ Slowly bend the front knee forward until a stretch is felt in the calf.
• ◉ 3 × 30 seconds per side.
• ◉ Perform 1–2× daily.

Calf and hamstring muscles

• ◉ Starting position on all fours.
• ◉ Slowly stretch the hips upward.
• ◉ Let the heels sink gently toward the floor without bouncing.
• ◉ Feel the stretch in the calf, hollow of the knee, and back of the thigh—without provoking pain in the hollow of the knee.
• ◉ Hold 3 × 30 seconds.
• ◉ Perform 1–2× daily.

Fascia roller

Fascia training supports the treatment of a Baker’s cyst because adhesive or tight fascia can increase pressure in the knee joint and hinder the drainage of synovial fluid. The goal is to improve tissue circulation and gliding.

Front thigh muscles

• ◉ Starting position lying on your stomach.
• ◉ Place a large roller under the thigh of the straight leg. Place the other leg bent to control movement.
• ◉ Actively roll the front thigh from the hip down to just above the knee joint.
• ◉ Perform the exercise slowly and in a controlled manner. Adjust pressure to personal perception, but work up to a tolerable pain threshold.
• ◉ Roll out localized adhesions more intensely or hold the position at that point.
• ◉ 3 minutes per side.
• ◉ Perform 1–2× daily.

Calf muscles

• ◉ One leg bent, the other leg on the fascia roller. Increase pressure by placing both legs on the roller. Further increase by stacking the legs.
• ◉ If pain occurs in the wrist, the exercise can also be performed on the forearms.
• ◉ Actively roll the calf from above the heel to just below the hollow of the knee.
• ◉ Perform the exercise slowly and in a controlled manner.
• ◉ Adjust pressure to personal perception, but work up to a tolerable pain threshold.
• ◉ Roll out localized adhesions more intensely or hold the position at that point.
• ◉ At least 3 minutes per side.
• ◉ Perform 1–2× daily.

Strengthening

Targeted strengthening relieves the knee joint, improves joint guidance, and can thus reduce pressure on the knee cyst. Exercises should be performed pain-free and in a controlled manner.

Squats

• ◉ Starting position: standing, feet slightly wider than hip-width and slightly externally rotated.
• ◉ Slowly and in a controlled manner, squat down—only as low as the Baker’s cyst in the hollow of the knee allows. Push the hips back and shift weight onto the heels.
• ◉ Make sure the force comes from the glutes. Stabilize the knees so they do not collapse inward or outward.
• ◉ Slowly and in a controlled manner, return to standing.
• ◉ If you have balance problems, you can hold on to a stable object with your hands.
• ◉ 3 sets of 8–12 repetitions.
• ◉ Perform 2–3× per week.

Heel raises

• ◉ Starting position: standing hip-width apart.
• ◉ Raise both heels slowly and in a controlled manner. Hold the top position briefly. Lower the heel again slowly and in a controlled manner.
• ◉ 3 sets of 8–12 repetitions.
• ◉ Perform 2–3× per week.