Healthy subject

Equipment: AU5-Harmonic, Esaote Biomedica (Genoa, Italy)

Transducer: 10 MHz, linear

Comments: Posterior transverse scan at the heel. t = Achilles tendon; f = retrocalcaneal fat pad.

Diagnosis: Seronegative spondyloarthropathy

Equipment: AU4-Idea, Esaote Biomedica (Genoa, Italy)

Transducer: 13 MHz, linear

Comments: Acute retrocalcaneal bursitis. Anechoic aspect of the synovial fluid (*) is one aspect of an exudative inflammation. t = Achilles tendon.

Diagnosis: Tendinitis of the Achilles tendon

Equipment: AU4-Idea, Esaote Biomedica (Genoa, Italy)

Transducer: 13 MHz, linear

Comments: Achilles tendon (middle third). Ultrasound examination shows a diffuse thickening and a focal area of reduced ecogenicity of the Achilles tendon. t = Achilles tendon.

Diagnosis: Psoriatic arthritis

Equipment: AU4-Idea, Esaote Biomedica (Genoa, Italy)

Transducer: 13 MHz, linear

Comments: Acute retrocalcaneal bursitis. Anechoic distension of retrocalcaneal bursa (*). t = Achilles tendon.

Diagnosis: Seronegative spondyloarthropathy

Equipment: AU4-Idea, Esaote Biomedica (Genoa, Italy)

Transducer: 13 MHz, linear

Comments: Retrocalcaneal bursitis. Retrocalcaneal bursa widening with clearly evident features of synovial proliferation (*), surrounded by a thin film of synovial fluid. t = Achilles tendon.

Diagnosis: Seronegative spondyloarthropathy

Equipment: AU4-Idea, Esaote Biomedica (Genoa, Italy)

Transducer: 13 MHz, linear

Comments: Retrocalcaneal bursitis. Ultrasound detects a hypoanechoic fluid collection within the retrocalcaneal bursa (*). t = Achilles tendon.

Diagnosis: Seronegative spondyloarthropathy

Equipment: AU4-Idea, Esaote Biomedica (Genoa, Italy)

Transducer: 13 MHz, linear

Comments: Ultrasound detects clearly evident erosions of the calcaneus (°). t = Achilles tendon; cb = calcaneal bone.