Bursitis is an inflammatory condition affecting the small-fluid-filled structures lining the joints. The most common knee bursae injuries are known to be the one affecting the kneecap and the other affecting the inner-knee.
Bursae in the knee act as a cushion or a shock absorber for the knee joint. The inflammation of the bursa is a result of an excessive or repetitive stress on the area.
The symptoms and causes of the different types of knee bursitis depend on the specific bursa that is affected.
In case of the knee, the pes anserine bursa is located on the tibia’s proximomedial aspect between the hamstring tendons and superficial medial (tibial) collateral ligament.
The importance of the pes anserine bursa is its ability to provide the space for motion between the superficial tibial collateral ligament and the hamstring tendons.
The hamstring tendons are the sartorius, gracilis, and semitendinosus, which are the primary flexors of the knee. These muscles are also necessary for internal rotation of the tibia.
The pens anserine bursa is located between these three tendons and the shinbone. Pens anserine bursitis is an inflammatory condition of the bursa as a result of overuse, incorrect training, and tight hamstrings.
The condition can also be seen in patients with degenerative knee conditions such as osteoarthritis. Obesity is also a known risk factor for bursitis.
In terms of age, younger athletes and individuals aged over 50 are known to be more prone to suffer from this condition.
The condition is characterized by an inflammation, which is a result of the bursa producing excess fluid that results in pressure on the adjacent parts of the knee.
The pain and swelling in this condition are localized to the area below the knee joint. The pain is also known to increase with activity, especially during ascending or descending stairs.
Support braces and self-care techniques, which include strengthening exercises, can be implemented to reduce pain and inflammation.
As tight hamstrings can cause several knee ailment, it is imperative to keep the hamstrings healthy and flexible with stretching and strengthening exercises.
Anatomy of Pes Anserine Bursa
The pes anserine bursa is also known as the ‘Goose Foot‘ because of its appearance. The bursa secretes synovial fluid to reduce friction between tissues.
The proper functioning of the knee involves frictionless movements between the muscle tendons and the bones. A friction between them could result in tears in the tendon and also damage the bones.
A constant pressure or stress on the bursa or the knee joint can make it susceptible to inflammation. When the pressure exerted is too much for the bursa, it reacts by thickening the synovial membrane.
The pes anserine area contains the sartorius, gracilis and semitendinosus muscles, which are situated superficial to the knee’s medial collateral ligament.
These three muscles are important for the proper movement of the knee as they are known as the primary flexors. The semitendinosus muscle belongs to the hamstrings muscle group, while the sartorius and gracilis muscles work to pull the leg towards the body’s median axis.
As the bursa acts as a cushion for tendons, muscles, and bones, an irritated bursa could cause pain and discomfort during movement and everyday activities.
Pens anserine bursitis is a gradual condition progressing over time and is related to overuse and improper training techniques. (1)
Research Opinions on Tendonitis vs Bursitis
There are several research studies on the subject to assess if the pain in the condition is a result of a bursitis or tendonitis. Studies are ongoing to evaluate the exact cause and the condition is now widely known as pes anserine bursitis/tendinopathy.
Tendonitis and bursitis are both characterized by degeneration or inflammation of soft tissues around bones and muscles.
Bursitis is an inflammation of the bursa, while tendonitis is a result of an overuse. Tendons are fibrous and dense structures situated at the narrowing of the muscles to a bone.
A healthy bursa protects the bone from stress when the tendon is pulling over a bone or around the corner of a bone. An inflammation of the bursa results in pain similar to that felt during tendinopathy.
Tendinopathy is characterized by a tenderness and feels warm to touch. (2)
Pes Anserine Bursitis Causes
The medial knee pain resulting from this condition can be a result of repetitive stress over the area.
The symptoms are known to appear gradually, but the mini-traumas could be avoided by knowing the causes of this condition.
Friction & Pressure
Athletes and non-athletes who actively use the three pens anserine muscles are prone to suffer from this condition. The repetitive stress on the area could be caused by cycling, uphill running, and swimming.
Running and cycling are known to be one of the most common activities that result in friction and repetitive stress on the region.
Individuals who are actively involved in running should ensure that proper footwear is worn for the terrain.
A direct blow to the area during sports or everyday activities could also result in swelling of the bursa. This is commonly noticed in athletes involved in football, volleyball, and skiing.
Such athletes can benefit from wearing protective braces or sleeves to ensure that a damage to the knee joint is prevented.
Improper Training Techniques
Exercising involves the use of the three pens anserine muscles, which can get stressed if proper techniques are not followed. The condition can be a result of a lack of proper warm-up and stretching period.
However, the most common reason is the implementation of a sudden increase in intensity and duration.
Proper shoes and equipment are also important to avoid inflammation of the bursa.
Tight Hamstring Muscle
Tight hamstrings are known to be a primary cause of most knee ailments. A tight hamstring muscle is associated with more pressure on the pes anserine tendons.
This could result in a damage to the tendons and an increased pressure on the pens anserine bursa.
A higher body weight is directly proportional to the pressure going through the bursa.
Therefore, obese individuals are susceptible to suffer from this condition as the pressure on the bursa increases with the weight.
This type of bursitis is commonly noticed in individuals with suprapatellar plical irritation, Osgood-Schlatter syndrome, and medial meniscal tears.
Diabetes patients are also known to be more prone to suffer from pes anserine bursitis.
Infected bursitis is indicated when microorganisms enter the body through an open wound following a trauma.
Pes Anserine Bursitis Symptoms
The symptoms of this condition are known to appear gradually as the repetitive mini-traumas start exerting pressure on the bursa resulting in irritation of the bursa and inflammation.
Inner Knee Pain
The pain is known to be localized to the medial aspect of the knee and is aggravated by walking on uphill areas.
The knee pain can also get worse by ascending or descending stairs or getting up from a seated position.
Tenderness & Swelling
The area could feel tender to touch with some swelling and redness.
The pain and inflammation could restrict movement of the knee.
As the pain limits the motion of the knee, it could result in a weakening of the muscles making it painful to carry out everyday activities.
The pain from bursitis is usually noticed at night when sleeping on the side with the legs together.
This position puts pressure on the bursa, which can result in pain and disturbed sleep. (3)
Are You at Risk?
Several underlying knee conditions could pose as a risk factor for pens anserine bursitis.
Understanding them is important to manage and treat the condition.
Age: The condition is commonly noticed in younger athletes and patients aged 50-80 years suffering from knee osteoarthritis.
Degenerative knee joint diseases: Pens anserine bursitis is noticed in 75% of knee joint patients.
Biomechanics: Pes planus, also known as flat foot, individuals are more prone to the condition along with other conditions affecting the medial knee.
Knee Deformity: A knee deformity along with collateral instability is known to increase the probability of suffering from this condition.
Diabetes: Some studies suggest the link between diabetes and a high prevalence of bursitis. Around 24% to 34% of people with type 2 diabetes reporting knee pain are known to be associated with pens anserine bursitis.
Sports Activities: Sports that require cutting or side-to-side movements.
Gender: The condition is more common in overweight females because of the different angulation of the knee. This results in an increased pressure on the bursa. (4)
Diagnosis of Pes Anserine Bursitis
Diagnosing the condition involves a physical examination to check for pain and inflammation at the medial side of the knee. The examination will also check for the presence of tight hamstrings.
Medical history and a detailed evaluation of physical activities are important to diagnose pes anserine bursitis. There are several underlying conditions that can make a person more prone to suffer from bursitis.
Imaging techniques such as X rays can be used to rule out fractures, trauma, or tumors. MRI scans are known to be effective in diagnosing bursitis and knowing the extent of damage to the tissues. (5)
A differential diagnosis to rule out the following considerations should also be undertaken.
- Medial meniscal tear
- Other knee bursitis conditions
- Spontaneous osteonecrosis
- Saphenous nerve compression (6) (7)
Pes Anserine Bursitis Treatment
Conservative treatment methods are known to effectively reduce pain and inflammation.
However, it is important to avoid any strenuous activity during the recovery period and it can impact the healing process and further aggravate the condition.
Pes anserine bursitis is a self-limiting condition and does not have any long-lasting effects.
The following techniques can be implemented at home. They work efficiently to reduce pain and inflammation and increase the knee’s range of motion.
When following the exercise routines, it is imperative to ensure that pressure is not exerted on the knee.
However, if a trauma has resulted in an open wound with knee pain, it could be an indication of an infected bursa. This needs medical intervention as antibiotics will be required to flush the infection out of the body.
Ignoring an open wound could cause more damage to the joint as well as adjoining structures.
Rest is necessary to alleviate the painful symptoms.
Patients are advised to avoid any offending activities and resume exercise gradually once the pain and inflammation are reduced.
Making an ice pack with a reusable ice bag and applying on the affected area can reduce pain and inflammation.
NSAID’s along with rest and ice are known as the first line of treatment for pes anserine bursitis.
Ibuprofen is the most commonly used NSAID medication, but it needs to be take after the prescription a health care provider.
Intrabursal injections of corticosteroids or local anesthetics are termed as the second line of treatment.
This is used only when the self-care techniques have not been able to reduce pain and inflammation.
It has been reported that repeated use of lidocaine injections or corticosteroids can result in long-term relief. However, only three injections should be used in a one year period.
This option is rarely used for pes anserine bursitis and is recommended only when a localized infection is indicated in an immunocompromised patient.
If standard antibiotic treatment is not providing relief, a surgical decompression could be undertaken for the bursa. (10)
In case of an infected bursa, the symptoms might include fever and a redness over the area. In such cases, aspiration might be required to drain the excess fluid from the bursa.
Certain nutrients and herbs are known to reduce pain and inflammation associated with bursitis.
Papaya: The papain enzyme in papaya reduces inflammation caused by bursitis.
Pineapple: Pineapple juice is known to contain bromelain, which decreases inflammation in bursitis patients.
Omega 3 Fatty Acids: Incorporating fish oil or flaxseed oil reduces the production of inflammatory substances.
Turmeric: The spice in the form of a paste or mixed in water can relieve the symptoms.
Ginger: Ginger tea with honey is known to reduce inflammation and infection.
Cayenne Pepper: Cayenne pepper improves circulation and offers relief from inflammation.
Epsom Salt: Soaking your leg in the magnesium-rich Epsom salt water can provide relief from inflammation and discomfort. (11)
Other than these therapies, alternative therapies such as acupuncture are also known to treat bursitis.
Pes Anserine Bursitis Exercises
A recovery program should include physical therapy to stretch and strengthen the hamstring and quadriceps groups.
Hamstring stretching exercises should be carried out regularly to gain maximum benefit from the program.
The physical therapy aims to reduce pain and inflammation in around six to eight weeks.
Tight hamstrings are the most common cause of knee injuries. A simple check for tight hamstrings involves touching your toes while keeping the knees straight.
If you have to bend your knees, it is probably because of tight hamstrings.
These stretches work towards reducing pain as well as improving function and flexibility.
While lying on the back, bend the knee to be stretched and use your hands to pull the leg towards you. One hand should be at the back of the calf and the other at the back of the thigh.
It is important to make sure that the knee is bent about 20° even when pulling it towards yourself. A slight stretch should be felt at the middle of the thigh. Hold this position for 30 seconds and repeat three times.
While sitting on the edge of a chair, bend the good knee and put the other knee in front of you. Maintain a slight bend in the good knee and lean forward to feel a light stretch at the back of the thigh.
It is important to keep your head up and back straight while performing this stretching exercise. Hold the position for 30 seconds and repeat three times.
While standing straight, take support of a chair or table with your hands. Lift the knee and bend it backwards towards your bottom.
It is necessary to make sure that the bending position does not cause discomfort. Hold the position for three to five seconds and repeat five to ten times in a day. (8)
Lie flat on the back with leg and the knee kept straight. Push the knee down by tightening the muscles at the front of the thigh.
This position should result in a clenching sensation at the thigh muscles. Hold this position for three seconds and repeat ten times every four hours. (9)
During the therapy, patients are advised to follow some instructions to improve the healing process. The aim of the therapy is to gain pain-free motion in the knee.
- Activity modification should be continued till the pain and inflammation go away completely.
- Gradually increase the intensity and duration of activities.
- Alternative training for cardiovascular fitness should be continued.
Usually, the condition can be resolved with conservative treatment, however, if the symptoms continue to persist limiting the range of motion, the following options can also be considered.
How to Prevent Pes Anserine Bursitis?
Pes anserine bursitis is most commonly a result of overuse or repetitive stress on the bursa. These gradual mini-traumas impact the bursa eventually resulting in bursal irritation.
Understanding the risk factors associated with this condition is important to prevent it. In case of athletes, knee injuries can be prevented with the use of knee braces or sleeves. Such braces should be considered especially in activities that involve the possibility of direct blows or tackles.
Managing underlying conditions such as diabetes and osteoarthritis is important for reducing the possibility of pes anserine bursitis. Diabetics are also recommended to check for any cuts or wounds regularly to prevent an infected bursa.
Tight hamstrings are known to cause several knee ailments, with pes anserine bursitis being one among them. To avoid this, it is essential to practice hamstring stretches and strengthening exercises to maintain flexibility and improve function.
Obesity is known to be a primary cause of bursitis as well as other knee injuries. A higher weight could lead to increased pressure on the knee resulting in mini-traumas on the bursa.
A BMI can serve as a screening tool to assess your weight and understand if you fall under the healthy range. A nutritional diet with an active lifestyle can help reduce weight and decrease the probability of bursitis.
Improper training techniques are known to cause pes anserine bursitis. These are commonly noticed when an individual experiences a sudden increase in intensity and duration of activity. It is advisable to build up flexibility before starting rigorous training routines.
Improper shoes, especially while running, can exert excessive pressure on the knees. Choose the right shoes for the activity and ensure that they fit properly.
Pes anserine bursitis is among the common knee bursitis conditions affecting people. It is said to be a result of overuse and excessive stress on the knee joint and the bursa.
Repetitive stress on the joint causes mini-traumas, which then make it more susceptible to inflammation. An excessive stress or pressure then leads to thickening of the bursal walls.
In case of the pes anserine bursa, it serves as a shock absorber between the tibia and the hamstring muscles. A raised pressure on the bursa is usually absorbed by increasing the synovial fluid secretion.
This increased secretion launches inflammatory reactions resulting in pes anserine bursitis.
As the pain and inflammation occur gradually are not noticed during the mini-traumas, it becomes necessary to understand the causes and risk factors associated with the condition.
Athletes are more prone to suffer from this condition as their activities put the joint and bursa in a constant pressure or stress. The likelihood of suffering from this bursitis is also high in individuals suffering from degenerative joint diseases.
The treatment techniques are usually conservative methods to reduce pain and inflammation. Surgical intervention is rarely recommended as a treatment for this bursitis.