Humeral torsional deformity after supracondylar osteotomy for cubitus varus: its influence on the postosteotomy carrying angle.

Humeral torsion was measured in 23 patients by computed tomography (CT) scan after supracondylar osteotomy for cubitus varus. The opposite unoperated humerus was used as the control. The mean torsion in the unoperated humerus was 70 degrees. Patients who did not have "derotation" of the distal fragment during osteotomy had approximately 30 degrees more internal torsion on the operated side than on the opposite side. The carrying angle after osteotomy was not influenced by lack of correction of torsional deformity in the humerus, and correction of torsion during osteotomy was not essential for correction of the carrying angle.