Supracondylar corrective osteotomy for cubitus varus--the internal rotation component and its importance. An unique...

In 20 patients with cubitus varus, a clinical test suggested by Yamamoto et al (1985) was carried out to measure the internal rotation. Average internal rotation was found to be 37.5 +/- 9.390. A correction for internal rotation was carried out for all the patients having angle more than 20 degrees. Following osteotomy, post-operative Yamamoto's angle was measured and was found to be 8.85 +/- 6.5. An experiment was carried out on postmortem human humerus with cubitus varus. The internal rotation was measured with Kirschner wires and was found to be 30 degrees. Osteotomy was carried out to eliminate varus and correct internal rotation. Radiographs taken before and after the osteotomy confirmed the correction. We conclude that this derotation has to be corrected and Yamamoto's test should be used to assess the correction.