- Percutaenous insertion into the proximal tibia surrounding the proposed osteotomy site under fluoroscopic guidance of 6 to 9 radio-opaque 0.8mm tantalum beads using a specifically designed gun. A standardized pattern of widespread tantalum bead distribution will be used. To avoid bead loosening caused by postoperative bone resorption, they will be placed a distance of at least 0.5 cm from the osteotomy line.