TY - JOUR T1 - Assessment of Enthesitis in Psoriatic Arthritis JF - The Journal of Rheumatology JO - J Rheumatol SP - 869 LP - 870 DO - 10.3899/jrheum.181380 VL - 46 IS - 8 AU - PHILIP S. HELLIWELL Y1 - 2019/08/01 UR - http://www.jrheum.org/content/46/8/869.abstract N2 - There has been an increasing focus on enthesitis in psoriatic arthritis (PsA). Enthesitis, defined as inflammation at the insertion of tendons and ligaments into bone, has been proposed as the primary pathological lesion of PsA, and this hypothesis has received support from animal models that have focused on the enthesis in spondyloarthropathy-like disease1,2. Enthesitis is part of the entry “stem” for the ClASsification for Psoriatic ARthritis criteria (CASPAR) criteria, although it must be emphasized that only a few cases of PsA had isolated entheseal involvement in that study3.Yet the clinical evaluation of enthesitis remains a vexing problem. When delivering educational symposia, I am often asked by dermatology and rheumatology colleagues how to assess and treat enthesitis. To the dermatologists I say look only at the Achilles insertion because (1) it is readily identifiable, (2) it is the major enthesis of the body, and (3) involvement is quite specific for spondyloarthropathy (SpA). I caution against misinterpreting a fusiform swelling of the Achilles tendon 5–10 cm proximal to the insertion as insertional tendinitis — Achilles paratendinitis is quite common and mostly unrelated to SpA. To the rheumatologist I give the same advice, but also advise using a simple enthesitis index for assessment, such as the Leeds enthesitis index, in which the patient is queried about pain when pressure is applied at each lateral epicondyle, medial femoral condyle, and Achilles tendon insertion. I warn about overinterpreting pure entheseal disease without arthritis for 2 reasons. First, there is a consistently … Address correspondence to Dr. P.S. Helliwell, Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, 2nd Floor, Chapel Allerton Hospital, Harehills Lane, Leeds LS7 4SA, UK. E-mail: P.Helliwell{at}leeds.ac.uk ER -