Silastic sphere arthroereisis for surgical treatment of flexible flatfoot: a preliminary report.

Numerous procedure have been proposed for the treatment of flexible flatfoot. Many procedures use bone blocks and bond grafts placed into the sinus tarsi to limit subtalar joint motion. Arthroereisis is the limitation of exogenous joint motion without complete arthrodesis. This has been performed by utilizing a variety of endoprosthetic devices. Some require suture or bone cement for placement. Such techniques may add to the complications and limitations of these procedures. When indicated, the implantation of a Silastic 3 sphere into the sinus tarsi appears to be a promising alternative. The procedure is uncomplicated and does not require an osteotomy, grafting, cement, or internal or external fixation. Joint integrity is maintained without violation of the talocalcaneal articular facets. Properly performed, the Silastic sphere is self contained and retained with minimal potential of subluxation. The sphere also functions with a "ball-bearing" action, thereby reducing the abrupt torsional forces of impaction while limiting excessive pronation.