抄録
For mono-compartmental osteoarthritis, we perform focal dome osteotomy distal to the tibial tuberosity using the Ilizarov apparatus. In this paper, we introduce a unique osteotomy technique. Before surgery, we designed a malalignment test to identify the source of the mechanical axis deviation and the center of rotaion of angulation (CORA). After the lower leg is fixed with the Ilizarov apparatus a Rancho Cube is attached to a rod connecting the proximal ring at the level of the CORA. A distal hole in the Rancho Cube is used as a drill guide. Next, the tibia is drilled through the hole of the Rancho Cube around the CORA. Circular osteotomy is accomplished by connecting the multiple drill holes with a small chisel. Using this technique it is possible to cut the bone around the CORA and preserve soft tissue around the osteotomy site. Acute correction is performed until the mechanical axis passes through the Fujisawa point. The advantages of the technique we introduced are high adjustability of the bone ends, large bone-to-bone contact, high primary stability, rapid bone healing and complete correction without translation.
