Pes Anserine Bursitis

Is pain on the inside of your knee making walking, climbing stairs or everyday activities increasingly uncomfortable?

Perhaps you've noticed a sharp pain when climbing a flight of stairs, getting up from a chair or going for your usual walk. Even activities you once enjoyed without a second thought can suddenly become painful and frustrating.

If you've been diagnosed with pes anserine bursitis, you'll know just how much this discomfort can interfere with your normal routine. Pes anserine bursitis occurs when a small fluid-filled sac on the inner side of your knee becomes irritated or inflamed. It commonly develops through repetitive strain, overuse or irritation of the surrounding tissues.

The good news is that many cases improve without surgery. Understanding what's causing the inflammation and which activities may be aggravating it can help you take the right steps towards recovery.

What Is Pes Anserine Bursitis?

Your knee relies on several small fluid-filled sacs called bursae to provide cushioning and reduce friction between the bones, muscles and tendons as you move.

One of these is the pes anserine bursa, located on the inner side of your knee, approximately 5–7 centimetres below the knee joint. It sits between the shinbone (tibia) and three tendons that attach to this area: the sartorius, gracilis and semitendinosus tendons. These tendons help support and control movement around your knee.

Interestingly, the term pes anserinus means "goose's foot", referring to the shape formed by the three tendons where they attach to the shinbone.

When the underlying bursa becomes irritated or inflamed, it may accumulate excess fluid, causing tenderness, swelling and pain. This condition is known as pes anserine bursitis, sometimes referred to as anserine bursitis or goosefoot bursitis. [1]

For a broader explanation of the different types of knee bursitis, visit our Knee Bursitis Information page.

What Are the Symptoms of Pes Anserine Bursitis?

One of the frustrating things about pes anserine bursitis is that your knee may feel reasonably comfortable at rest, only to become painful when walking or climbing stairs.

Common symptoms include:

• Pain on the inside of the knee: Usually felt several centimetres below the knee joint, towards the upper shin.

• Pain when climbing stairs: Discomfort that becomes more noticeable when walking upstairs or downstairs.

• Tenderness to touch: The affected area may feel particularly sensitive when pressed.

• Localised swelling: Mild puffiness or swelling around the inner knee, although this isn't always visible.

• Pain after sitting: Discomfort or stiffness when standing up after sitting with your knees bent for an extended period.

• Pain during physical activity: Walking longer distances, running or certain exercises may aggravate symptoms.

Symptoms often develop gradually rather than following one particular injury. Because the discomfort occurs close to the knee joint itself, it's sometimes mistaken for other knee problems, including arthritis or a meniscus injury.

What Causes Pes Anserine Bursitis?

Pes anserine bursitis generally develops when the bursa is subjected to repeated friction, pressure or excessive strain. Although athletes can develop the condition, it can also affect people who aren't particularly active.

Common contributing factors include:

Repetitive Walking or Running: Activities involving repeated knee movement, particularly running, climbing hills or suddenly increasing your walking distance, can place additional strain on the surrounding tissues.

Tight Hamstring Muscles: Tightness in the hamstring muscles may increase tension around the tendons attaching near the pes anserine bursa.

Knee Osteoarthritis: People with osteoarthritis of the knee may be more susceptible to pes anserine bursitis, particularly when changes in joint movement place additional stress on the surrounding tissues.

Altered Knee Alignment: Certain alignment differences, including knock knees or flat feet, may affect how forces are distributed around the knee.

Excessive or Unfamiliar Physical Activity: Sometimes the problem develops after taking on more activity than your knee is accustomed to handling.

Perhaps you've started walking longer distances, returned to exercise after a break or spent an unusually active weekend gardening. Often, several factors contribute rather than one identifiable cause. [1]

Why Can Pes Anserine Bursitis Be Painful When Climbing Stairs?

If you've been experiencing pes anserine bursitis, you may have noticed that climbing stairs is particularly uncomfortable. This is because the muscles and tendons around your inner knee are working to support your body weight and control movement as you step up or down.

When the bursa beneath these tendons is already irritated, the additional movement and loading can aggravate the sensitive tissues. This can explain why walking on level ground may feel relatively comfortable, while climbing stairs produces a noticeable increase in pain.

The important thing is to listen to what your knee is telling you... If a particular activity consistently aggravates your symptoms, temporarily reducing its intensity or frequency may help prevent further irritation.

Pes Anserine Bursitis vs Knee Arthritis – What's the Difference?

Pes anserine bursitis and knee osteoarthritis can produce similar symptoms, particularly when pain occurs along the inner side of the knee. However, they affect different structures.

Pes anserine bursitis involves inflammation of the cushioning bursa located below the inner knee joint.

Knee osteoarthritis involves changes affecting the cartilage and other structures within the joint itself.

A useful distinction is the location of the pain. Pes anserine bursitis typically causes localised tenderness several centimetres below the inner knee joint, whereas osteoarthritis commonly produces discomfort closer to the joint line itself. However, both conditions can occur together.

Because other problems, including meniscus injuries, can produce similar pain, a professional assessment is important when the cause is uncertain.

How Is Pes Anserine Bursitis Diagnosed?

If you're experiencing persistent pain around the inside of your knee, it's worth having the condition properly assessed.

A healthcare professional will generally begin by discussing your symptoms, recent activities and any existing knee problems. They may examine your knee to identify the location of tenderness, assess your range of movement and check whether certain movements reproduce the pain.

In many cases, a clinical examination provides enough information to make an initial diagnosis. However, additional investigations may be recommended when another condition is suspected.

Ultrasound: An ultrasound can help assess the pes anserine bursa and surrounding soft tissues, including signs of inflammation or fluid accumulation.

MRI Scan: An MRI may be useful when a more detailed examination of the knee's internal structures is required.

X-rays: Although X-rays don't directly show an inflamed bursa, they may help identify arthritis, fractures or other bone-related problems.

What Are the Treatment Options for Pes Anserine Bursitis?

If you've been struggling with persistent inner knee pain, your first priority is understandably to find some relief. Treatment generally focuses on reducing irritation, managing discomfort and restoring comfortable movement.

1. Rest and Activity Modification

Temporarily reducing activities that aggravate your knee is often a sensible first step. You may need to limit longer walks, running, repetitive stair climbing or other movements that consistently increase discomfort. However, prolonged complete inactivity isn't generally necessary.

Gentle movement can often be maintained, provided it doesn't significantly aggravate your symptoms. The aim is to allow the inflammation to settle without developing unnecessary stiffness or muscle weakness.

2. Heat Therapy

For ongoing knee stiffness or surrounding muscle tension, applying a warm compress or heat pack for 15–20 minutes may help improve comfort. 

Heat may be particularly useful when the surrounding muscles feel tight or uncomfortable after periods of inactivity. However, heat may not be suitable immediately following an acute injury or when significant swelling is present. Cold therapy may be preferable during an acute flare-up.

3. Physiotherapy and Rehabilitation

Physiotherapy can play an important role in managing pes anserine bursitis, particularly when tight hamstrings, muscle weakness or altered knee movement contribute to symptoms.

During the painful stages, strenuous exercises or activities that repeatedly aggravate the inflamed bursa may need to be avoided or modified. Gentle movement and carefully selected exercises can often be maintained.

As the inflammation and associated pain settle, rehabilitation may focus on:

• Improving hamstring flexibility.
• Strengthening the muscles supporting the knee.
• Restoring comfortable movement.
• Improving knee stability and control.
• Reducing the likelihood of recurring irritation.

The timing and intensity of rehabilitation should be suited to the individual's condition.

Appropriate activity modification and conservative management should form part of the pes anserine bursitis recovery process. [2]

4. Medication and Medical Treatments

Pain-relieving or anti-inflammatory medication may help manage discomfort, although these treatments aren't suitable for everyone.

In some cases, a healthcare professional may consider a corticosteroid injection when symptoms remain particularly troublesome. However, injections aren't generally the first treatment option and should be considered alongside the potential risks and benefits. 

Surgery is rarely required for uncomplicated pes anserine bursitis.

5. Drug-Free, Non-Invasive Knee Bursitis Relief with OSMO Patch

If you're looking for a drug-free, non-invasive way to help manage the swelling and associated pain from knee bursitis, the OSMO Patch offers a convenient home treatment option.

Simply apply the patch over the affected area before going to bed and let it work while you sleep.

Designed to help reduce swelling and associated discomfort, OSMO Patch may provide effective relief alongside appropriate rest and activity modification.

Discover how OSMO Patch may help you manage knee bursitis swelling and associated pain — so you can get back to enjoying your everyday activities.

>> Learn More About OSMO Patch for Knee Bursitis Relief →

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How Long Does Pes Anserine Bursitis Take to Heal?

Recovery times vary depending on the severity of the inflammation, how long you've had symptoms and whether other knee problems are contributing to the discomfort.

Many uncomplicated cases improve over several weeks, although persistent symptoms may take longer. Continuing to perform activities that repeatedly aggravate the affected area can delay recovery.

It's also worth remembering that feeling less pain doesn't necessarily mean the surrounding tissues are ready for strenuous activity. Gradually returning to normal exercise and everyday activities may help reduce the likelihood of another flare-up.

Frequently Asked Questions About Pes Anserine Bursitis

Why Does the Inside of My Knee Hurt When I Walk Upstairs?

Climbing stairs places additional demands on the muscles and tendons supporting your knee.

If the pes anserine bursa is inflamed, this movement may aggravate the sensitive tissues and cause pain just below the inner knee joint.

However, other knee conditions can produce similar symptoms, so persistent pain should be properly assessed.

Can Pes Anserine Bursitis Cause a Lump on the Inside of My Knee?

Yes. Inflammation may cause localised swelling or puffiness around the inner knee, although a large, obvious lump isn't particularly typical.

If you've developed a new or persistent lump, it's important to have it examined, as not every swelling around the knee is caused by bursitis.

Is It Okay to Keep Walking with Pes Anserine Bursitis?

Gentle walking may be fine if it doesn't significantly aggravate your symptoms.

However, longer distances, hills or repeated stair climbing may increase discomfort.

Temporarily reducing your walking distance and gradually increasing activity as symptoms improve may help.

Can Pes Anserine Bursitis Be Mistaken for a Meniscus Tear?

Yes. Both conditions can cause pain around the inner side of the knee.

However, pes anserine bursitis generally causes tenderness below the joint line, while a medial meniscus injury more commonly produces pain at the joint line itself.

Meniscus injuries may also cause catching, locking or other mechanical symptoms. A healthcare professional can help distinguish between the conditions.

Should I Use Heat or Ice for Pes Anserine Bursitis?

It depends on your symptoms.

Cold therapy may help manage discomfort following a recent injury or during an acute flare-up.

Gentle heat may be more comfortable when symptoms involve ongoing stiffness or muscle tension.

Avoid applying heat to an unusually hot, red or potentially infected area.

Can Pes Anserine Bursitis Heal Without Surgery?

Yes. Most cases improve with conservative treatment, including activity modification, appropriate rehabilitation and pain management.

Surgery is rarely necessary for uncomplicated pes anserine bursitis.

When Should You Seek Medical Attention?

If pain around the inside of your knee persists, worsens or significantly interferes with walking, sleeping or everyday activities, consult a qualified healthcare professional.

Seek prompt medical attention if you experience severe pain following an injury, an inability to bear weight, marked swelling, or a hot, red knee accompanied by fever.

Medical References

[1] American Academy of Orthopaedic Surgeons (AAOS): Pes Anserine (Knee Tendon) Bursitis. Read the AAOS medical resource

[2] Cleveland Clinic: Pes Anserine Bursitis – Symptoms, Causes and Treatment. Read Cleveland Clinic's medical guidance