The word enthesitis isn’t one that naturally rolls off the tongue. In fact, it’s not even used that commonly by doctors or nurses unless they specialize in the area of rheumatology. It is, however, an important factor in psoriatic arthritis, so it’s useful to know about to better understand the disease.

Enthesitis is the inflammation of the entheses, which are the places where tendons or ligaments attach to bones. Tendons attach muscles to bones while ligaments attach bones to one another. In the first study of its kind among patients with PsA, it was observed that about 35% of patients had enthesitis.


Enthesitis associated with PsA is a result of the inflammation that is caused by the immune system disorder that is at the root of the disease.

Enthesitis creates pain, stiffness and tenderness at the area of attachment. It is also often accompanied by swelling at the larger attachment points in the lower limbs. It commonly occurs at the attachments in the heel, knee, hip, toes, fingertips, elbow, backbone and bottom of the foot.


One of the challenges for those not yet diagnosed with PsA is that such pains can be dismissed as an injury from another cause -- imagine that nagging ‘running injury’ that just doesn’t seem to heal. Enthesitis can also be misdiagnosed as another condition that can produce similar pains or discomfort.

Three independent risk factors have been found for people with PsA to develop enthesitis: A higher body mass index (BMI, or weight/height ratio), a higher number of actively inflamed joints, and being a younger age.

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