Discriminant validity study of Achilles enthesis ultrasound.

OBJECTIVE: We want to know if the ultrasound examination of the Achilles tendon in spondyloarthritis is different compared to other rheumatic diseases.

MATERIAL AND METHODS: We studied 97 patients divided into five groups: rheumatoid arthritis, spondyloarthritis, gout, chondrocalcinosis and osteoarthritis, exploring six elementary lesions in 194 Achilles entheses examined.

RESULTS: In our study the total index ultrasonographic Achilles is higher in spondyloarthritis with significant differences. The worst elementary spondyloarthritis lesions for discriminations against other pathologies were calcification.

CONCLUSIONS: This study aims to demonstrate the discriminant validity of Achilles enthesitis observed by ultrasound in spondyloarthritis compared with other rheumatic diseases that may also have ultrasound abnormalities such enthesis level.