At site of swelling pointed by patient, there is Focal area of synovial sheath thickening involving tibialis anterior tendon. Minimal fluid was noted in adjacent sheath. Local hypervascularity is seen in thickened sheath. Tendon echopattern is normal - fibrillar type without any hypoechoic areas.
No tendon tear is noted.
Last image shows side by side comparision of symptomatic and asymptomatic tendons in short axis.
Symptomatic side shows hypoechoic thickened sheath around tendon which is absent around asymptomatic tendon.
Asymptomatic tendon appears tobe hypoechoic than symptomatic one , due to anisotropy artifact.