The ankne is a modified hinge, complex weight bearing joint and has an important role in walking. And the lateral malleolus of fibula has important role in maintaining the stability of ankle joint supprting one-sixths of its weight, and moves 3mm downward on weight bearing. And its talar articular surface is 5.8 mm wider laterally than medially.

And diastasis of the ankle joint is associated with extensive ligamentous rupture.

Many various treatment about ankle fractures assoclated wih diastasls have been reported, and rigid internal fixation with trans-syndesmotic screw fixation is a general opinion.

But its complication and appropriate indications are rather troublesome.

Recently, Boden reported establishment of stability of distal tibiofibular joinin diastasis combining fractures, without syndesmotic screw fixation.

The following clinical results were shown by analysis of 11 cases of ankle fractures associated with diastasis, treated by rigid bimalleolar internal fixation without syndesmotic screw fixation in the Department of Orthopedic Surgery, Hallym University, College of Medicine for two years, from Jan. 1988 to Dec. 1989.