Weight-Bearing-Line Analysis in Supramalleolar Osteotomy for Varus-Type Osteoarthritis of the Ankle by Naoki Haraguchi, Koki Ota, Naoya Tsunoda, Koji Seike, Yoshihiko Kanetake, and Atsushi Tsutaya J Bone Joint Surg Am Volume 97(4):333-339 February 18, 2015 ©2015 by The Journal of Bone and Joint Surgery, Inc.

Technique for making the hip-to-calcaneus radiograph. Technique for making the hip-to-calcaneus radiograph. The patient maintains a bipedal stance on a radiolucent platform and faces the long film cassette. For the lowest point of the calcaneus to be visualized on the radiograph, the cassette is slid into position with its lower edge passing the edge of the platform. The patient’s patella is placed forward. The x-ray beam is centered on the knee of the imaged leg from a distance of 2 m. Voltage and current are 200 mA and 85 kV, respectively. It is important to confirm on the radiograph that the patella is centered between the femoral condyles. Naoki Haraguchi et al. J Bone Joint Surg Am 2015;97:333-339 ©2015 by The Journal of Bone and Joint Surgery, Inc.

Distribution of the preoperative mechanical ankle joint axis points and the postoperative mechanical ankle joint axis points of each ankle. Distribution of the preoperative mechanical ankle joint axis points and the postoperative mechanical ankle joint axis points of each ankle. A total of eleven ankles had a preoperative mechanical ankle joint axis point of ≤0% (preoperative points for these ankles are indicated by red diamonds). These points did move somewhat laterally with surgery, but many of these points did not reach 60% of the ankle joint (postoperative points for these ankles are indicated by red diamonds). Naoki Haraguchi et al. J Bone Joint Surg Am 2015;97:333-339 ©2015 by The Journal of Bone and Joint Surgery, Inc.

Preoperative hip-to-calcaneus radiograph showing obliteration of the joint space between the medial malleolus and the medial facet of the talus with subchondral bone contact and the mechanical axis (red line) passing through the medial part of the ankle joint. Preoperative hip-to-calcaneus radiograph showing obliteration of the joint space between the medial malleolus and the medial facet of the talus with subchondral bone contact and the mechanical axis (red line) passing through the medial part of the ankle joint. Naoki Haraguchi et al. J Bone Joint Surg Am 2015;97:333-339 ©2015 by The Journal of Bone and Joint Surgery, Inc.

Hip-to-calcaneus radiograph made three years after supramalleolar osteotomy. Naoki Haraguchi et al. J Bone Joint Surg Am 2015;97:333-339 ©2015 by The Journal of Bone and Joint Surgery, Inc.

The lower part of the postoperative hip-to-calcaneus radiograph shows that the mechanical axis (red line) has been transferred to the lateral part of the ankle, and the joint space between the medial malleolus and the medial facet of the talus has opened. The lower part of the postoperative hip-to-calcaneus radiograph shows that the mechanical axis (red line) has been transferred to the lateral part of the ankle, and the joint space between the medial malleolus and the medial facet of the talus has opened. Naoki Haraguchi et al. J Bone Joint Surg Am 2015;97:333-339 ©2015 by The Journal of Bone and Joint Surgery, Inc.

Bar graph showing the postoperative improvement in scores for the three groups based on the postoperative mechanical ankle joint axis point (<60% for nine ankles, 60% to 79% for eight, and ≥80% for nine). Bar graph showing the postoperative improvement in scores for the three groups based on the postoperative mechanical ankle joint axis point (<60% for nine ankles, 60% to 79% for eight, and ≥80% for nine). The top and bottom of each box represent the 75th and 25th percentiles, the horizontal line inside the box represents the median, the diamond represents the mean, and the whiskers are the minimum and maximum values. There was significantly greater improvement in the ankles with a postoperative mechanical ankle joint axis point of ≥80% than in the ankles with a postoperative mechanical ankle joint axis point of <60% (p = 0.030; Wilcoxon rank-sum test with Bonferroni correction). The asterisk indicates a significant difference. Naoki Haraguchi et al. J Bone Joint Surg Am 2015;97:333-339 ©2015 by The Journal of Bone and Joint Surgery, Inc.