Kyphoplasty.

A variant of vertebroplasty known as "kyphoplasty" has been suggested for correcting vertebral compression fractures. A balloon placed inside the vertebral body is inflated to create a cavity, thereby restoring vertebral body height and allowing low-pressure cement injection. This procedure is gaining popularity in the United States. Over 1000 patients had been treated by the end of 2000. However, kyphoplasty is costly (chiefly because the balloon is disposable) and has not been evaluated in carefully designed studies. Although retrospective findings have been reported as highly promising, they are not sufficient to validate this procedure. The principle is innovative and the procedure deserves further investigation as a potentially effective means of correcting loss of vertebral height. Furthermore, use of a bone substitute instead of cement deserves investigation.

Intralesional Ethibloc Injections in Bone Cysts.

Benign bone cysts (aneurysmal and unicameral) often require treatment to prevent pathological fractures. Percutaneous injections are less invasive than surgery. We describe the different percutaneous treatments available: local injection of steroids, calcitonin, or bone marrow in unicameral bone cysts, and Ethibloc(R)(Ethicon, Ethnor Laboratories, Nevilly Sur Seine, France) injection in both unicameral or aneurysmal bone cysts. Within the tumor, histologic modifications usually occur after these injections, due to the fibrogenic properties of the agent. Therefore, we emphasize the necessity of obtaining an histologic proof before any injection, especially in aneurysmal bone cysts.