Pes anserinus refers to the inflammation of the pes anserine bursa, and a resultant pain and impaired mobility to the inside of the knee. The pes anserine bursa (fluid-filled pad that acts as a cushion at the joints) is located on the inside of the leg, just below the knee; between the tibia (shin bone) and some tendons as they attach onto the tibia.

Bone structure diagram showing location of inflammation known as pes anserinus.

What causes this condition?

Inflammation at the pes anserine bursa is caused by repetitive friction over the bursa, usually caused by a sudden increase in load through the knee. For example, a large, sudden increase in training load or a change in type of training. This is often experienced by long distance athletes such as cyclists or runners. It can also be caused by tightness of the muscles of the thigh, weakness of the stabiliser muscles of the leg, or anatomical abnormalities of the leg.

What are the symptoms of pes anserinus?

The most common symptom is pain at the inside of the knee, just below the knee joint. The pain is usually aggravated by ascending/descending stairs, sleeping on your side with the knees together, crossing one leg over the other, or getting out of the car. Stiffness and pain is also often felt on initially getting up in the morning, lasting just over an hour. Weakness of the leg and changes in gait pattern (walking posture) may also be noted.

What can Physiotherapy do to help?

Physiotherapy is proven to be the best treatment for this kind of inflammation, by addressing the factors causing it. This may mean:

(a) adjusting your training plan

(b) releasing tight muscles

(c) teaching you exercises to strengthen the weak muscles, or

(d) giving you home advice on how to manage your condition.

If you are struggling with pain on the inner knee, our team of Physiotherapists are trained and ready to assist you in working towards pain-free movement once again.

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