The Shape and Size Discrepancy between Bone and Prosthesis in Total Knee Arthroplasty

Cho, Woo Shin; Moon, Ho Saeng; Park, Su Sung; Noh, Kyoung Min; Cha, Ho In

Abstract

To determine size and shape discrepancy between the bone of Korean women and the prostheses in total knee arthroplasty, the height(antero-posterior length) and width(medio-lateral length) of the distal femur and the proximal tibia were measured at the bone resection level for 104 knees of 62 female patients who underwent primary total knee arthroplasty and compared with the same parameters of the total knee prostheses designed by five different companies. On the condition that the height of the prostheses matched with each cases of the bone were optimal, the difference in the width was evaluated, and the criteria of the discrepancy were overhang if the width of the prosthesis was larger than bone, optimal if width of the prosthesis was same or smaller and difference was within 5 mm, and down-size if smaller and difference was over Smm. In femoral prostheses, 34.6% of all were optimal, 13.1%, overhang and 52.3%, down-size. In tibial prosthesis, 54.1% of all were optimal, 13.9%, overhang and 32%, down-size. In conclusion, although further investigation for clinical application is needed, there were discrepancies in size and shape between the femur and tibia of Korean women and total knee prostheses and improvement in design should be considered.