Knee bursae#Frontal

{{Short description|Fluid-filled sacs of the knee joint}}

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| Name = Knee bursae

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| Caption = Sagittal section of right knee-joint, thus showing only frontal bursae.

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The knee bursae are the fluid-filled sacs and synovial pockets that surround and sometimes communicate with the knee joint cavity. The bursae are thin-walled, and filled with synovial fluid. They represent the weak point of the joint, but also provide enlargements to the joint space.Platzer (2004), p 26 They can be grouped into either communicating and non-communicating bursae or, after their location – frontal, lateral, or medial.

==Frontal==

File:Knee effusion, annotated.jpg extending into the suprapatellar bursa.]]

In front, there are five bursae:

1. the suprapatellar bursa or recess between the anterior surface of the lower part of the femur and the deep surface of the quadriceps femoris.Burgener (2002), p 390 It allows for movement of the quadriceps tendon over the distal end of the femur. In about 85% of individuals, this bursa communicates with the knee joint. A distension of this bursa is therefore generally an indication of knee effusion.{{cite web|url=https://radiopaedia.org/articles/suprapatellar-bursa|title=Suprapatellar bursa|author=Daniel J Bell and Brian Gilcrease-Garcia|website=Radiopaedia}}
2. the prepatellar bursa between the patella and the skin It allows movement of the skin over the underlying patella.
3. the deep infrapatellar bursa between the upper part of the tibia and the patellar ligament. It allows for movement of the patellar ligament over the tibia.Cipriano (2002), p 358. (A brief description of the "clinically important bursae in the anterior aspect of the knee")
4. the subcutaneous (or superficial) infrapatellar bursa between the patellar ligament and skin.
5. the pretibial bursa between the tibial tuberosity and the skin. It allows for movement of the skin over the tibial tuberosity.