The primary goal of treatment of the posterior lip fracture is to effect the returning of normal function that is accomplished by the early institution of motion.

A variety of both open and closed treatment have been recommended, but many authors have advocated internal fixation of large fragments that compromise 25 per cent or more of the articular surface on the lateral radiography

Open reduction with internal fixation of the posterior lip fragment has been associated with technical problems. VisualiBation of the articular surface is obscure by overhanging of the posterior tibial margin and talus. And than efforts at open reduction of posterior lip fragments are frequently unsuccessful. We used the posteromedial approach to this lesion.

The results obtained from this study were as follows;

1. Of the 17 cases, male was 9 cases(53%), female was 8 cases(47%) the most common victim was twentieth and thirtieth decades.

2. The mean afticular surface involvement of the posterior lip fragments in the sagittal plane were 28 percent.

3. The location of posterior lip fragment was central(2 cases), posteromedial(6 cases), posterolateral(9 cases).

4. The posteromedial approach affords the most predictable way to cary out an absolutely anatomic reduction of posterior lip fractures and a low complication rate.