Hip Effusion (Transient synovitis) of the hip
Self-limiting condition in which there is an inflammation of the inner lining (the synovium) of the capsule of the hip joint.
Physical exam and radiography are common tools for diagnosis, sonography is a great tool that increases acuracy.
Patients tupically present with limping. In the LT Hip you can see an anechoic space (red) consistent with fluid. If very large or infectious etiology is of concern an Ultrasound guided needle aspiration may be performed.