Knee Bursa

There are approximately 14 knee bursa. Bursa are small fluid filled sacs found all over the body. They reduce the friction between 2 surfaces, usually muscle and bone, a bit like ball bearings. This allows everything to move smoothly preventing inflammation.

Sometimes, the knee bursa get damaged, known as bursitis, which can cause pain. This is usually when there is excessive friction over the bursa causing it to either become inflammed, or it dries out so it no longer works properly.

There are 5 main bursa that work to protect the knee. They are:

1) Prepatellar Bursa

This is found infront of the kneecap. Inflammation of this occurs when there is repeated friction over the kneecap, such as with prolonged forward kneeling. This is known as Housemaids Knee but today is more common in trades such as roofers and carpet fitters.

2) Semimembranosus Bursa

knee bursa ;locations

This is found at the back of the knee between the semimembranosus muscle (one of the hamstring muscles) and the medial head of gastrocnemius (one of the calf muscles). Inflammation of this is known as a Bakers Cyst

3) Infrapatellar Bursa

This is found underneath the kneecap. Inflammation is known as Clergyman's Knee and is usually caused by more erect kneeling than with Prepatellar bursitis

4) Suprapatellar bursa

This is found above the kneecap underneath the quadriceps tendon at the bottom of the thigh.

5) Pes Anserine Bursa

This is found on the inner side of the knee approx 2 inches below the joint with the sartorius, gracilis and semitendonosis muscles. Inflammation of Pes Anserine is especially common in runners.

Other Knee Bursa

The other bursa knee locations are:

Anteriorly (front of the knee): pretibial and deep infrapatellar bursa

Medially (inner side): medial gastrocnemius bursa, the bursa between semitendonosus tendon and the head of the tibia and occasionally there is a bursa between the tendons of semimembranosus and semitendinosus

Laterally (outer side): lateral gastrocnemius, fibular, fibulopopliteal and the subpopliteal bursae

Possible Problems

Problems usually develop in the bursa when there is muscle tightness and/or weakness which causes excessive friction on the bursa. The knee bursa can become either

1) Inflamed - ie swollen known as bursitis or
2) Dried out - ie they loose the fluid inside them.

This results in more friction on the bone and muscles/tendons leading to bursa knee pain. Usually a combination of exercises, medication and/or injections helps them to recover. Visit the Bursitis of the knee section to find out more about prevention and bursitis treatment.

Go to Anatomy Guide or Homepage


Your Comments

Share your knee pain experiences with others, whether it be ideas, top tips, things that worked well for you, problems you've had etc.......

© knee-pain-explained.com 2010-2014
Updated 15th October 2014
All rights reserved. Terms & Conditions apply

Protected by Copyscape Online Copyright Search

The material on this website is intended for educational information purposes only.  It should not substitute medical advice, diagnosis or treatment.


KneePainExp

See Also

Anatomy Guide

How can I strengthen my leg?

Test your flexibility - would stretching help you?

What is causing my knee pain?



Search This Site


Visitor Comments

“This is one of the best self-help & info sites of any medical condition I've ever seen. Excellent work.” Amy, UK

“Thanks to KPE.com. Lots of improvement after just two days.” Suresh, India

"This is the best self-help site I have ever seen for knee pain. It is very difficult to find such a comprehensive volume of information on one site without being advised to "Just purchase this product!" Many, many thanks" Jennifer, US

"Superb site, many thanks, so much helpful content especially the targeted strengthening exercises for me.” Gerri, UK

“Thank you so much, your response makes so much sense. Thank you again for your time in answering my questions.” Cynthia, US

"Your website is a gold mine, thank you very much."
Gavril, Denmark

"I LOVE your website. Out of all the others, yours is so informational and easy to read." Michelle, US

"This is the best site dealing with knee problems that I have come across. I will be putting the stretches and exercises into practise. Thank you!"
Margaret, S. Africa