Ultrasound findings in intersection syndrome

The purpose of our study is to demonstrate the role of ultrasound as a first-line technique in the evaluation of intersection syndrome, reporting and illustrating its typical and atypical findings. In a 2-year period, we reviewed nine patients who received an ultrasound examination for non-specific inflammatory signs in the distal forearm: four men (28-53 years old) and five women (34-57 years old), with a mean age of 44.1 years. The ultrasound examination revealed, in all patients, the presence of peritendinous oedema and a small amount of synovial fluid within the tendon sheaths at the crossing intersection point between the first and the second dorsal extensor tendon compartments, with loss of the hyperechoic cleavage plane between the two tendon groups. In two patients, we observed an irregularly thickened tendon sheath, with small hyperechoic nodules within the fluid, related to proliferation of the synovial membrane. In one case, we detected a relevant thickening of the extensor carpi radialis longus and brevis tendon. Only one patient showed moderate muscle oedema within the first extensor compartment muscles, while another one had significant subcutaneous oedema. Ultrasound is effective in the first-level diagnosis of intersection syndrome.