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Infrapatellar fat pad irritation:
symptoms, what it means, and practical next steps

Not all front of knee pain is “kneecap pain” or arthritis. Infrapatellar fat pad irritation – sometimes called Hoffa’s fat pad impingement – is a common but often misunderstood cause of sharp pain at the very front of the knee, just below the kneecap.

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This page explains how fat pad irritation typically behaves, how it differs from patellofemoral pain, when imaging is considered, and what usually helps.

 

It’s aimed at active adults 45–70 in Camberwell and Melbourne’s inner east who want a clear, realistic explanation and a plan that respects their everyday life.

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What you’ll learn on this page

  • How to recognise a typical fat pad irritation pattern

  • Key differences between fat pad pain and kneecap pain

  • Simple stance and activity tweaks that can reduce irritation

Typical symptoms & patterns

The infrapatellar fat pad is a small, highly sensitive pad of tissue that lives just below your kneecap and behind the patellar tendon.

When irritated, people often notice: 

  • Pinpoint pain at the front of the knee, usually just below or to either side of the bottom of the kneecap

  • Pain that’s worse when the knee is fully straight or “locked back”, especially with prolonged standing

  • Discomfort with straight-knee landings, running downhill, jumping, or walking fast with a very straight leg

  • Sometimes increased pain with kneeling directly on the front of the knee

  • A sense of puffiness or fullness at the front of the joint in some cases

 

Unlike patellofemoral pain, which is often more diffuse around the kneecap and aggravated by flexed-knee load (stairs, squats), fat pad irritation is typically more localised and linked to end-range extension or impact in a straight-ish knee.

Why it happens

Your infrapatellar fat pad sits between the lower end of the femur and the upper tibia, just under the patella. It helps cushion the joint and has a rich nerve supply, which is why it can be very sensitive when irritated.

 

Irritation often relates to:

  • Repetitive impingement – the fat pad gets pinched between the kneecap and the thigh or shin bone, especially with hyperextension (knee pushed backwards) or rapid straight-knee impact.

  • Sudden change in activity – e.g. more downhill walking, jumping, or standing with knees locked straight

  • Previous surgery or trauma, which can change local tissue sensitivity and mechanics

  • Coexisting conditions – fat pad irritation can occur alongside patellofemoral pain, tendon problems, or osteoarthritis, particularly in older knees.

 

Because the fat pad is so well innervated, relatively small mechanical changes can feel disproportionately painful – even if scans don’t show dramatic damage.

When to see someone – and when to scan

​When to see a physio

Consider an assessment if:

  • You have persistent pain just below the kneecap that’s not settling with simple rest

  • Locking your knee straight, long periods of standing, or straight-knee landings are consistently aggravating

  • You’ve been told it’s “just tendon” or “just arthritis” but the pattern doesn’t quite fit

  • You’re avoiding movement because you’re worried about making the pain worse

 

When scans may be considered

There is no single “fat pad scan” that is always required. Clinical assessment usually leads the way. MRI or other imaging may be discussed if:

  • There was significant trauma or prior surgery and your symptoms are not following an expected course

  • There are concerns about other structures (e.g. meniscus, ligament injury, or advanced arthritis)

  • Pain remains severe and persistent despite careful conservative management

 

Even when MRI shows fat pad oedema or impingement, treatment decisions are still based on your symptoms, function, and goals – not the scan alone.

How we assess & plan at The Hip and Knee Physio (Camberwell)

In your first appointment for suspected fat pad irritation, we’ll typically:

  • Clarify your symptom pattern – exact location, aggravating positions, daily irritants, and any history of surgery or trauma

  • Observe your posture and stance – especially how you naturally stand (locked vs soft knees) and how you load the joint when walking, stepping, or landing

  • Test strength and control around the hip, knee, and ankle in extension and slight flexion

  • Screen for other contributors to front-of-knee pain, including patellofemoral joint, tendon, and osteoarthritic features

 

From there, we’ll outline:

  • Key posture and movement changes to take pressure off the fat pad

  • A graded loading plan to build strength and confidence without constant aggravation

  • Whether we need to involve your GP (e.g. for medication or imaging discussions) or, in rarer cases, an orthopaedic opinion

 

You can also explore the Patellofemoral Pain and Knee Physiotherapy pages and the dedicated fat pad blog for more context, then come back here when you’re ready to book.

FAQs – Patellofemoral pain

1. Why does locking my knee make the front hurt?

When you lock your knee fully straight, the fat pad can be pinched between the bones of the joint and the underside of the kneecap. In an already irritated fat pad, that extra compression can feel sharp or burning, especially if you stand like this for long periods.

 

2. Is this the same as kneecap (patellofemoral) pain?

No. Both cause front-of-knee pain, but:

  • Fat pad irritation is usually more focal just below the kneecap, and worse with locked or hyperextended positions.

  • Patellofemoral pain is usually more diffuse around or behind the kneecap, and aggravated by bent-knee loadsuch as stairs, squats, or sitting.

 

It’s possible to have features of both, which is why a careful assessment matters.

 

3. Can I still walk or cycle with fat pad irritation?

Often yes – the goal is usually to keep you moving, but with less repeated impingement. That might mean shorter walks at first, avoiding steep downhills, using a softer knee on impact, or choosing cycling positions that don’t cause repeated end-range extension. The plan is tailored to your tolerance

Local practicals – Camberwell clinic

​The Hip and Knee Physio consults from 1/3 Prospect Hill Road, Camberwell, a short walk from Camberwell Junction and public transport. The building offers good access and facilities, including accessible entry and amenities, and there is parking available nearby.

Book Now

If front of knee pain is starting to limit your walking, stairs, or confidence, a structured assessment can help you understand what’s going on and what to do next.

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  • Book a fat pad pain consult in Camberwell – Book Now Hip and Knee Physio

  • Prefer to talk first? You can contact the clinic to discuss whether an appointment is appropriate for your situation

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