Analytical techniques using multiple-exposure roentgenograms were
employed to investigate surgical repositioning of either the femoral or the
tibial attachment of the medial collateral ligament. The motion of the
femoral attachment of the ligament with respect to the tibial attachment
was used to compute the changes in length of the borders of the ligament
for normal knees and for knees with repositioned attachments. The results
support the conclusion that when advancement of the medial collateral
ligament is utilized in the treatment of medial instability, optimization
is accomplished by distal and anterior advancement with the knee in 30
degrees of flexion. Femoral displacement (proximal realignment) or tibial
displacement at knee-flexion angles greater than 45 degrees is not
recommended.