What is fat pad syndrome?

Fat pad syndrome physiotherapy may help if you get sharp pain at the front of your knee, especially as you straighten it. Fat pad syndrome (also called Hoffa’s syndrome or infrapatellar fat pad impingement) occurs when the fat pad beneath your kneecap becomes irritated or compressed. The fat pad acts like a natural shock absorber. However, when it swells, it can become painful and sensitive.

Even small increases in pressure can flare symptoms. For example, repeated knee strain, frequent squatting, sudden training increases, or standing with knees “locked back” can aggravate the area. If your pain feels more general, start with our guide to knee pain and common contributors.

Front-of-knee pain can overlap with other conditions. For comparison, read about patellofemoral pain syndrome (PFPS) and runner’s knee, as symptoms can look similar.

Common causes

Fat pad syndrome can follow a direct knock to the knee, such as a fall or contact during football, or it can build gradually over time. Often, the issue relates to repeated compression at the front of the knee.

Contributing factors may include:

• Tight quadriceps or hip flexors
• Repeated knee hyperextension (locking the knee back)
• Altered kneecap tracking, including PFPS
• Pelvic, hip, or foot posture changes that shift load forward
• Post-surgical irritation (particularly after knee procedures)
• knee osteoarthritis alongside anterior knee sensitivity

Lower limb biomechanics matter. Excess load through the front of the knee during walking, running, stairs, or squatting can keep the fat pad irritated. A physiotherapist will often look at hip strength, calf control, and foot mechanics because they influence how your knee tracks and loads.

Symptoms of fat pad syndrome

Symptoms commonly include:

• Sharp pain under or beside the kneecap
• Pain that increases when the knee fully straightens
• Discomfort with walking, stairs, running, or squatting
• Swelling around the kneecap
• Pain when standing with knees “locked back”
• Sensitivity when kneeling

Many people feel better with a slight bend in the knee because this can reduce compression on the fat pad.

People also ask: is fat pad syndrome the same as runner’s knee?

Not always. Runner’s knee is a broad term for knee pain in runners and often includes conditions like PFPS, tendon irritation, and fat pad irritation. Fat pad syndrome tends to flare most when the knee fully straightens or “locks back”, while other causes may hurt more with deep squats or longer sitting. A physiotherapy assessment helps confirm what is driving your pain and which changes will matter most.

Diagnosis

A physiotherapist or sports doctor can often diagnose fat pad syndrome with a clinical assessment. Key findings may include tenderness beside the patella and pain during quadriceps contraction. Imaging such as MRI can help confirm inflammation and rule out other knee pain causes.

Assessment should also check hip strength, gait, and foot mechanics. These factors often influence whether the knee hyperextends, collapses inward, or loads the front of the joint.

Treatment options

Most people improve with non-surgical care. Treatment focuses on settling irritation, reducing front-of-knee compression, and rebuilding control.

• Load modification to reduce fat pad compression
• Taping or padding strategies that may reduce symptoms during activity
• Strength work for quadriceps, hips, and calf (progressed to suit your irritability)
• Mobility work for stiff or tight regions (as needed)
• Gait and movement coaching to reduce knee hyperextension and improve alignment
• Footwear advice or orthotic review if foot posture strongly affects knee load

A structured plan usually blends symptom control with graded strengthening. Start with our general guide to knee exercises, then progress with a tailored knee treatment plan based on your findings and goals.

Do you need surgery?

Most people recover without surgery. Injections or surgical options are usually considered only when long-standing swelling or mechanical irritation does not respond to a well-structured conservative program. Your physiotherapist can discuss options with your GP or sports doctor if progress stalls.

Preventing recurrence

Prevention focuses on improving strength and control through the hip, knee, and ankle, while avoiding repeated knee hyperextension. Supportive footwear, sensible training progressions, and early response to front-of-knee pain also help reduce flare-ups.

If your symptoms started after an operation, you may also benefit from a staged return using our post-operative rehabilitation guide as a general framework.

Related articles

• Patella Tendinopathy
• Patellofemoral Pain Syndrome
• Chondromalacia Patella
• Osgood-Schlatter Disease
• Sinding-Larsen-Johansson Syndrome
• Knee Bursitis
• ACL Injury
• Common Sports Knee Injuries
• Osteoarthritis of the Knee

What to do next

If your pain is sharp at the front of the knee, avoid repeatedly locking the knee back and reduce activities that trigger symptoms for a short period. Then, rebuild strength and control with a graded plan. If symptoms persist beyond 1–2 weeks, recur often, or limit your work or sport, book a physiotherapy assessment so we can confirm the driver and guide your progression.

References

• Abelleyra Lastoria DAA, Benny CK, Hing CB. Predisposing factors for Hoffa’s fat pad syndrome: a systematic review. Knee Surg Relat Res. 2023;35(1):17. doi:10.1186/s43019-023-00192-4. Available from: https://pubmed.ncbi.nlm.nih.gov/37296488/
• Wang MG, Seale P, Furman D. The infrapatellar fat pad in inflammaging, knee joint health, and osteoarthritis. NPJ Aging. 2024;10:34. Available from: https://pubmed.ncbi.nlm.nih.gov/39009582/
• Pereira Herrera B, Emanuel K, Emans PJ, et al. Infrapatellar fat pad as a source of biomarkers and therapeutic target for knee osteoarthritis. Arthritis Res Ther. 2025;27:81. Available from: https://pubmed.ncbi.nlm.nih.gov/40188073/
• DuBose JJ, Taqi A. Hoffa Pad Impingement Syndrome. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023–. Available from: https://www.ncbi.nlm.nih.gov/books/NBK589637/