Enthesitis is a condition where the entheses – sites where tendons and ligaments insert and attach onto the bone surface become painful and inflamed. 1 This inflammation is thought to be the result of faulty signaling between cells in the immune system.1
The development of enthesitis has been associated with the presence of HLA B27, a gene strongly linked to Ankylosing Spondylitis (AS).2 The two conditions often occur together, with between 25 and 58% of AS patients also reporting enthesitis.2 In fact, the link is so strong that enthesitis has been defined as a characteristic feature of AS.2
Enthesitis can strike anywhere the bone meets tendon.3 It frequently affects sites commonly associated with AS, for example the pelvis and the lower back. However, enthesitis pain can also be experienced in the periphery – the knees, the heels, (which is the most frequent site) and the soles of the feet.3 This means that the pain in any of these areas as well as in the lower back could all be warning signs of possible AS.4,5
Enthesitis is often underdiagnosed in the clinic.5 It can be tricky for your doctor to spot as the obvious symptoms are not always present and current diagnostic methods lack sensitivity.2 You can help overcome these obstacles by keeping a record of your symptoms with the tracker above.
Fill the tracker in over the course of a month, noting location of pain and the number of days it has appeared then show it to your doctor at your next appointment. A big-picture view of your symptoms may help your doctor diagnose enthesitis more quickly and precisely. This, in turn, will contribute to a better understanding of your overall disease state and greater likelihood of diagnosing AS.
In terms of how your doctor will diagnose enthesitis, the first step will usually be a physical examination, pressing at the ends of tendons and ligaments to check for pain.6 Ask your doctor to check any areas where you have experienced pain.
Sometimes, lack of apparent swelling or inaccessibility of the site of pain can prevent physical diagnosis.5,6 In this case imaging technologies, such as ultrasound or MRI can be used.2,5,7 These technologies are also more sensitive than physical assessments, if your doctor has not detected enthesitis but you’re still in pain, you may wish to ask them to explore these options to confirm their diagnosis.2,5,7
As with many aspects of AS, a diagnosis of enthesitis may take time to confirm. While you wait, there are a number of steps you can take to manage your discomfort. General self-care tips for inflammation will work well – warm baths, insoles and cushioning, ice packs to sooth swollen joints. Evidence from AS patients suggests that massages may also help relieve pain and improve quality of life.8
If you think you or anyone you know may be affected by enthesitis, start keeping a record of your symptoms and talk to a doctor about your options.
This article was written by Dr Shashank Akerkar, with help from the resident experts at ThisASLife.com. A social site helping the whole AS community to: Learn. Share. Inspire. Discuss.