Knee Bursitis: Symptoms, Types, Causes and Treatment

Knee bursitis is a common condition that can make every step painful, limit your mobility, and interfere with your daily life. Whether you are an athlete, a senior, or someone who just wants to stay active, understanding knee bursitis is essential for effective prevention, early detection, and targeted treatment. In this comprehensive guide, we’ll break down the symptoms, types, causes, and evidence-based treatment options for knee bursitis, empowering you to take charge of your joint health.

Symptoms of Knee Bursitis

Knee bursitis doesn’t always announce itself loudly, but its symptoms can significantly impact your quality of life. Early recognition of the signs is crucial for timely intervention and better outcomes. Most people notice pain or swelling around the knee, but the specifics can vary depending on which bursa is inflamed.

Symptom	Description	Common Sites	Source(s)
Pain	Localized, sharp or aching	Medial, anterior, posterior knee	1 2 3 4 5
Swelling	Visible or palpable lump	Below kneecap, inner knee, back of knee	1 2 4 5 6
Tenderness	Increased sensitivity to touch	Medial/anterior tibia, over bursa	1 3 5
Stiffness	Reduced range of motion	General knee area	2 6

Table 1: Key Symptoms

Pain

Pain is the hallmark of knee bursitis. It often starts gradually and can be sharp or aching, depending on the underlying cause and the specific bursa involved. Medial knee pain is especially common in anserine (pes anserine) bursitis and medial collateral ligament (MCL) bursitis, while pain in the front of the knee suggests prepatellar or suprapatellar bursitis. Posterior pain may indicate a popliteal cyst or subgastrocnemius bursitis 1 2 3 5.

Swelling

Swelling is another classic sign, sometimes appearing as a visible lump or bulge. In prepatellar bursitis, the swelling is often right over the kneecap. Anserine bursitis can cause swelling on the inner side of the knee, just below the joint, while popliteal cysts cause swelling at the back of the knee 1 2 4 5 6.

Tenderness

Tenderness to touch is a key diagnostic clue. In anserine bursitis, pressing just below the inner side of the knee elicits pain. MCL bursitis is also associated with localized tenderness, which helps differentiate it from meniscal injuries or other knee problems 1 3 5.

Stiffness

People with knee bursitis may notice stiffness, especially after periods of inactivity. This can limit the knee’s range of motion and make simple activities—like climbing stairs or rising from a chair—much more difficult 2 6.

Types of Knee Bursitis

The knee contains multiple bursae—small, fluid-filled sacs that cushion and reduce friction between bones, tendons, and skin. Each bursa can become inflamed due to different causes and presents with slightly different symptoms. Here are the main types of knee bursitis:

Type	Location	Unique Features	Source(s)
Prepatellar	Over kneecap	Common in "housemaid’s knee", swelling in front	4 10
Suprapatellar	Above kneecap	Often in OA, causes swelling above patella	6 8
Anserine (Pes Anserine)	Inner knee, below joint line	Medial pain, common in OA, obesity, women	1 3 7 9
MCL (Medial Collateral Ligament)	Between MCL layers	Rare, medial pain, history of trauma or valgus stress	5
Infrapatellar	Below kneecap (superficial or deep)	Swelling below patella, often from repeated kneeling	4
Popliteal (Baker’s cyst)	Back of knee	Posterior swelling, often with OA	2 4
Subgastrocnemius	Back of knee, below gastrocnemius	Associated with popliteal cysts, OA	2

Table 2: Main Types of Knee Bursitis

Prepatellar Bursitis

“Housemaid’s knee” is the popular name for prepatellar bursitis, which develops over the kneecap. It’s most often seen in people who spend a lot of time kneeling, such as gardeners or tradespeople. The swelling is prominent and visible right at the front of the knee 4 10.

Suprapatellar Bursitis

Located just above the kneecap, the suprapatellar bursa can become inflamed in people with osteoarthritis (OA) or after injury. This type often leads to swelling above the kneecap and may be associated with large fluid collections 6 8.

Anserine (Pes Anserine) Bursitis

This type affects the inner side of the knee, just below the joint, where three tendons insert. Anserine bursitis often causes medial knee pain, and is more common in women, older adults, people with obesity, and those with OA 1 3 7 9.

MCL Bursitis

The bursa between the layers of the medial collateral ligament can become inflamed, usually due to trauma or chronic strain. It’s rare but important to distinguish from other causes of medial knee pain 5.

Infrapatellar Bursitis

There are two infrapatellar bursae (superficial and deep), both located below the kneecap. Bursitis here is often caused by repetitive kneeling (sometimes called “clergyman’s knee”) and leads to swelling just below the patella 4.

Popliteal (Baker’s Cyst) and Subgastrocnemius Bursitis

Baker’s cysts form at the back of the knee and can be mistaken for other causes of posterior knee swelling. They often occur alongside OA and can be associated with subgastrocnemius bursitis, which is linked to joint abnormalities and cartilage damage 2 4.

Causes of Knee Bursitis

Knee bursitis can be triggered by a wide variety of factors. Understanding these causes can help you prevent flare-ups and target your treatment more effectively.

Cause	Description	At-Risk Groups	Source(s)
Repetitive stress	Frequent kneeling or bending	Tradespeople, athletes	4 10
Trauma	Direct blow or injury to the knee	All ages	4 5 10
Osteoarthritis	Joint degeneration, inflammation	Older adults, OA patients	1 2 3 6 7 8
Obesity	Increased pressure on knee structures	Overweight individuals	1 3 7
Diabetes	Increased risk of certain bursitis types	Diabetics	3
Valgus/Varus Deformity	Abnormal knee alignment	People with knee deformity	1 5
Infection (septic bursitis)	Bacterial infection of bursa	Immunocompromised, after injury	10
Rheumatoid/Autoimmune	Systemic inflammatory disorders	RA patients	5

Table 3: Common Causes of Knee Bursitis

Repetitive Stress and Trauma

Repeated kneeling or trauma is a leading cause of prepatellar and infrapatellar bursitis. Occupations or hobbies involving frequent pressure on the knees—such as gardening, cleaning, or certain sports—make individuals more susceptible. A single blow to the knee can also inflame a bursa 4 5 10.

Osteoarthritis and Joint Degeneration

Osteoarthritis is one of the most significant risk factors for knee bursitis. Degenerative changes in the joint can lead to increased friction and inflammation of the surrounding bursae, especially the anserine and suprapatellar bursae. Many patients with OA experience bursitis as a complication, particularly if they are also overweight or have joint deformities 1 2 3 6 7 8.

Obesity and Diabetes

Obesity increases the mechanical load on the knee, placing extra stress on bursae and tendons. Anserine bursitis, in particular, is more prevalent in overweight women with knee osteoarthritis. Diabetes is another predisposing factor, possibly due to microvascular changes and impaired tissue healing 1 3 7.

Malalignment and Deformity

People with valgus (“knock knees”) or varus (“bow legs”) deformities are at higher risk for certain types of bursitis, such as anserine and MCL bursitis. These alignment issues change the way forces are distributed across the knee, increasing the risk of friction and inflammation 1 5.

Infections and Systemic Disease

Septic bursitis, while uncommon, can occur when bacteria enter the bursa after injury or through the bloodstream. Autoimmune diseases like rheumatoid arthritis can also trigger bursitis as part of a broader inflammatory process 5 10.

Treatment of Knee Bursitis

Effective treatment for knee bursitis depends on the type, severity, and underlying cause. Most cases improve with conservative measures, but some require more advanced therapies.

Treatment	Method/Approach	Indication	Source(s)
Rest & Ice	Activity modification, cold packs	First-line for all types	4 10
Aspiration	Removal of bursal fluid	Large swellings, diagnosis, infection concern	4 6 8 10
NSAIDs	Oral or local anti-inflammatories	Pain, inflammation	3 7 9
Steroid Injections	Local corticosteroid injection	Persistent or severe symptoms	1 3 4 7 8
Physiotherapy	Strengthening, stretching	Recovery, prevention	3 7
Viscosupplementation	Hyaluronic acid injections	OA-related suprapatellar bursitis	8
Platelet-Rich Plasma (PRP)	Injection of concentrated growth factors	OA with suprapatellar bursitis	6
Mesotherapy	Subcutaneous medication injections	Anserine bursitis, pain control	7 9
Antibiotics	Oral/IV for septic bursitis	Infection	10
Surgery	Excision of chronic bursa	Refractory, chronic cases	4 5 10

Table 4: Evidence-Based Treatments

Conservative Management

Most knee bursitis cases respond well to conservative treatments:

• Rest and Ice: Reducing activity and regularly applying ice packs can help control pain and swelling, especially in acute cases 4 10.
• Aspiration: Removing excess fluid from the bursa provides immediate relief and helps rule out infection 4 6 8 10.
• NSAIDs: Both oral and topical nonsteroidal anti-inflammatory drugs reduce pain and inflammation. Mesotherapy (injecting small doses directly under the skin) has been shown to be effective with fewer side effects compared to oral NSAIDs 3 7 9.

Injections and Advanced Therapies

• Steroid Injections: Corticosteroid injections into the bursa are highly effective for persistent symptoms, particularly in anserine and suprapatellar bursitis. Ultrasound guidance improves accuracy and outcomes 1 3 4 7 8.
• Physiotherapy: Guided exercises improve flexibility and strength, helping to prevent recurrences and improve function 3 7.
• Viscosupplementation: Hyaluronic acid injections are beneficial in OA-related suprapatellar bursitis, reducing inflammation and improving joint lubrication 8.
• Platelet-Rich Plasma (PRP): Emerging evidence suggests that PRP injections can reduce inflammation, swelling, and pain in suprapatellar bursitis associated with OA 6.

Management of Complicated Cases

• Antibiotics: Septic bursitis requires prompt antibiotic therapy, and sometimes aspiration or drainage 10.
• Surgery: Surgical excision of the affected bursa is reserved for chronic, refractory cases that do not respond to conservative management 4 5 10.

Conclusion

Knee bursitis is a multifaceted condition with several types, causes, and management strategies. Early recognition and tailored treatment are key to a quick and lasting recovery.

Main points to remember:

• Symptoms include pain, swelling, tenderness, and stiffness, varying by bursa location.
• Types of bursitis depend on the affected bursa: prepatellar, suprapatellar, anserine, MCL, infrapatellar, popliteal, and subgastrocnemius.
• Causes range from repetitive kneeling and trauma to osteoarthritis, obesity, diabetes, malalignment, and infection.
• Treatment is usually conservative: rest, ice, NSAIDs, aspiration, steroid injections, physiotherapy, and in some cases, advanced interventions like viscosupplementation, PRP, or surgery.

Understanding these aspects of knee bursitis can guide you toward effective prevention, timely diagnosis, and optimal management—helping you get back on your feet with confidence.