Objective: Enthesopathy is one of the features characterizing patients with spondylarthropathies. Its diagnosis is usually based on clinical symptoms such as the presence of calcanear pain or tenderness at the insertion(s) of ligaments. More objective ways to estimate the presence and nature of enthesopathy are needed. Therefore, we analysed both by clinical and sonographic methods the presence of enthesopathy in the lower extremities of patients with spondylarthropathy.
Methods: 31 consecutive patients with spondylarthropathies (15 with reactive arthritis, 12 with ankylosing spondylitis, and 4 with psoriatic arthritis) were studied for the presence of enthesopathy in the lower extremities, independently by clinical examination and by high resolution sonography.
Results: Sonography detected inflammatory lesions in 44 entheses of 20 patients. Oedema at the insertion of the tendon was the most common finding. Signs of enthesitis were more common in the lower portion of the leg. In addition to enthesitis, bursitis was a common finding by sonography. By clinical examination, enthesitis was diagnosed in 56 sites in 20 patients, most frequently at the insertions of the Achilles tendon and the plantar fascia. Bursitis around the calcaneus and synovitis/pain in the hip and knee joints were most frequently misinterpreted to indicate enthesopathy at the clinical examination. In addition, half of the insertions with only oedema at sonography were clinically asymptomatic.
Conclusions: Sonographic examination of ligamentous insertions offers morphologic information which is unobtainable by the clinical judgement of tenderness in the estimation of enthesopathy in patients with spondylarthropathies.