To define the significant factors for lateral condyle prominence following the lateral closing wedge osteotomy for cubitus varus.

Analyzed the 15 cases performed lateral closing wedge osteotomy for cubitus varus. We measured the carrying angle by the arm and forearm axis lines of soft tissues, lateral condyle prominence index, the distance from center of rotation to osteotomy site and the distance from center of rotation to elbow joint.

The lateral condyle prominence group with lateral condyle prominence index (LCPI) over 300% was 5 cases (33%), and no prominence group was 10 cases (67%). The distance between CORA and osteotomy site in lateral condyle prominence group was mean 44 mm (range, 35-52) and no prominence group was mean 21 mm (range, 17-27). The distance between CORA and elbow joint was mean -3 mm (range -15~7) and 16 mm (range, 8-24) respectively.

Lateral condyle prominence was developed in case of the increased preoperative LCPI, increased distance between CORA and osteotomy site, and decreased distance between CORA and elbow joint.