Preoperative planning for lower extremity osteotomies - An analysis using 4 different methods and 3 different osteotomy techniques

Lower extremity osteotomy is a common procedure for managing deformity and unicompartmental gonarthrosis. One consideration not typically addressed is how the osteotomy will affect the leg length of the extremity. This articl e presents a numerical analysis of apparent leg-length change before and af ter osteotomy surgery. It also compares the differences resulting from the 3 different major types of osteotomies (closing wedge, opening wedge, and d ome). Three different preoperative planning methods and a fourth intraopera tive technique were studied. Using different methods of preoperative planni ng with the same osteotomy technique resulted in leg-length changes of 0.5 to 3 mm. Differences >7 degrees in lower extremity alignment may result dep ending on the planning method used. When comparing osteotomy techniques, 2 cm in leg-length difference was calculated.