A multiloculated fluid equivalent signal cystic structure, measuring 10 x 22 x 38 mm, with sharply defined margins, is located over the dorsolateral aspect of the wrist. It has a thin capsule and appears to have an elongated pedicle originating from the scapholunate articulation, sagittal. This pedicle traverses the space between the second and fourth common extensor compartments, moving into the subcutaneous region and lying superficial to the second extensor compartment and extensor pollicis longus tendon.
