“The infrapatella fat pad is also sometimes known as Hoffa's pad. It is a soft tissue that lies beneath the kneecap which can get impinged causing knee pain.

Fat pad impingement symptoms include tenderness around the bottom and under the kneecap. Patients may have a history of being able to over straighten the knee, called knee hyperextension or genu recurvatum. In some cases the bottom of the kneecap may be tilted outwards due to swelling underneath. 

In the case of a forceful direct impact to the kneecap, the fat pad can become impinged (pinched) between the femoral condyle and the patella. As the fat pad is one of the most sensitive structures in the knee, this injury is known to be extremely painful. This condition is normally long-standing as it is aggravated by extension or straightening of the knee joint. Hence the fat pad comes under constant irritation and may become significantly inflamed.

Treatment of this condition is normally by conservative methods as opposed to through surgery. Rest and avoiding aggravating activities. Apply Ice or cold therapy to reduce pain and inflammation. Ice can be applied for 10 minutes every hour initially reducing as symptoms improve. 

Your physiotherapist may use electrotherapy such as ultrasound and TENS. Muscle strengthening exercises to maintain the strength and fitness of the surrounding muscle groups should be done as pain allows.

Taping the patella is known to be highly effective in fat pad impingement.”

REF:http://www.sportsinjuryclinic.net/sport-injuries/knee-pain/fat-pad-impingement 

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