Quadriceps - suprapatellar impingement syndrome

Case contributed by Dr Gaurav Som Prakash Gupta


History of pain on lateral aspect of knee for long time, increased since 3 month. No history of trauma.

Patient Data:

Age: 60
Gender: Male

This MR revealed altered (fluid like) signal replacing the normal fat signal in the Quadricep fat pad /suprapaterllar fat pad. The posterior margin of the Quadricep fat pad is mildly convex, which is indicative of mass effect over the Suprapatellar recess.

There is minimal joint effusion. 

There are Subchondral cystic changes and Subchondral irregularity involving the Lateral Femoral trochlear  articular surface also minimally in the patellar articular surface. Only minimal thinning of the patella-femoral articular cartilage is seen. 

The Prefemorall suprapatellar fat pad is normal. The Hoffas fat pad is also normal. The suprapatellar and the infra patellar tendons are normal. The lateral and medial patellar retinaculum are normal. NO patellar subluxation is evident.

The Tibeo-femoral joint cartilage is normal. The PCL/ACL/Menisci/Collateral ligaments are normal.

Case Discussion:

These findings are consistent with Quadricep fat pad impingement syndrome. There is associated Patello-femoral joint degenerative changes.

There are three fat pads in relation to the anterior portion the knee joint. 

  • The Suprapatellar fat pads include the anteriorly located Quadricep fat pad and the posteriorly located prefemoral fat pad. 
  • The Infrapatellar fat pad is also know as Hoffas fat pad. 

Several conditions may involve these fat pads, mostly related to the poor bio-mechanics at the patellofemoral joint. The major conditions include:

Updating… Please wait.


Error Unable to process the form. Check for errors and try again.

Alert_accept Thank you for updating your details.