Spectrum of ultrasound pathologies of Achilles tendon and plantar aponeurosis entheses in patients with suspected enthesitis

Purpose: Ultrasonographical assessment of pathological changes in Achilles tendon and plantar aponeurosis entheses in patients with suspected enthesitis.

To examine prospectively with ultrasonography what kind of pathologies are seen in Achilles tendon and plantar aponeurosis entheses in patients with suspected enthesitis.

Material and methods: 30 painful Achilles tendons and 38 painful plantar aponeurosis entheses were examined with ultrasound in 28 men and 40 women, mean age 68 years, in order to confirm a clinical diagnosis of enthesitis. Ultrasound examinations were performed with an Esaote MyLab Class C scanner with linear 18 MHz transducer.

Results: 20% of Achilles tendon and 45% of assessed plantar aponeurosis entheses were found to have no abnormalities. The most common Achilles tendon pathologies included: mineralized scars within enthesis (i.e. enthesophytes) (70%), delaminated tendons at the level of the Achilles bursa (40%), exudate in the Achilles tendon bursa (27%), bony erosions at the enthesis attachement site (27%), edema of Kager's fat pad (20%), and increased vascularity of the Kager's fat pad (20%). Any case of increased vascularization of entheses. The only cases with increased vascularity were found in Achilles tendons and originated from the inflammed Kager's fat pad (13%) and achillobursitis calcanei (10%). The most common pathological changes of plantar aponeurosis included aponeurosis (body structure) delamination tears (34%), mineralized scars within the enthesis (enthesophytes) (29%). Any case with vascularization.

Conclusions: The results of the study indicate that clinical diagnosis of enthesitis is difficult to confirm with ultrasononography. The most frequent findings are not specific for enthesitis, and more probable reflects degeneration and microtrauma, except in certain cases of achillobursitis calcanei.