Metacarpal rotational osteotomy.

Maximum metacarpal rotation and corresponding phalangeal correction were measured in 80 fingers of 40 cadaver hands. Total metacarpal rotation averaged 50 degrees to 52 degrees in the index, long, and ring fingers and 69 degrees in the small finger. Phalangeal correction averaged 36 degrees to 37 degrees in the index, long, and ring fingers and 50 degrees in the small finger (70% of rotation in the metacarpal). The orientation of the metacarpophalangeal joint was not a significant limiting factor. However, the deep transverse metacarpal ligament did limit maximum rotation at the metacarpal and the phalanx. The advantages of basal metacarpal osteotomy make this technique the procedure of choice for correcting malrotation of up to an average of 18 degrees to 19 degrees for the index, long, and ring fingers. For the small finger, 20 degrees to 30 degrees of correction is possible, depending on the direction of rotation. A table has been devised to predict the correction for individual digits.