Deep infrapatellar bursa

The deep infrapatellar bursa is situated directly posterior to the distal 38% of the patellar tendon, just proximal to its insertion on the tibial tubercle. This bursa does not communicate with the knee joint. Its average width at the most proximal margin of the tibial tubercle is slightly wider than the average distal width of the patellar tendon. The deep infrapatellar bursa is partially compartmentalized by a fat pad apron extending from the retropatellar fat pad, dividing it into anterior and posterior compartments.[1]

MRI studies have shown that the deep infrapatellar bursa extends beyond the lateral margin of the patellar tendon in all cases, and a fat apron partially separating this structure is commonly observed.[2] The dimensions of the deep infrapatellar bursa in the craniocaudal, mediolateral, and anteroposterior planes are approximately 25 mm, 28.7 mm, and 6 mm, respectively.[2]