The Change of Mechanical Angle after High Tibial Osteotomy using Blade Plate

Cho, Se Hyun; Park, Hyung Bin; Song, Hae Ryong; Koo, Kyung Hoi; Jeong, Soon Taek; Ha, Yong Chan; Ha, Sung Jin

Abstract

PURPOSE
To search cause of recurrence of varus deformity and to correlate the mechanical angle of the knee joint at the third postoperative month following high tibial osteotomy to the final mechanical angle and to the clinical results.
MATERIALS AND METHODS
Study of thirty knee joints with lateral closed wedge osteotomy and fixation with 90-degree angle blade plate. Plateau-Blade angle was measured to evaluate the loss of correction at the osteotomy site. At the third postoperative month, the knees were divided into two groups according to the mechanical angle. Group I included the patients with valgus angle (16 knees) and group II included the patients with varus angle (14 knees) . The final mechanical angle was measured and the clinical results were evaluated with the knee score and the function score of Knee Society.
RESULTS
Plateau-Blade angle decreased 2.5 in group I and 4.8 in group II at postoperative three month. At the final follow-up, the loss of correction angle was 0.8 in group I and 2.3 in Group II (p>0.05) . The final knee score was 86 in group I and 80 in group II (p>0.05) . The final function score was 90 in Group I and 80 in Group II.
CONCLUSIONS
Because the final function score of valgus angle group is superior to that of varus angle group and recurrence of varus was mainly occur within postoperative three months, meticulous postoperative management needed to maintain valgus mechanical angle.