Résumé
PURPOSE: To investigate the effect of lateral buttress on the fracture healing of Jensen type 4 intertrochanteric fracture of the femur treated by dynamic compression hip screw (DCS) in elderly patients, retrospectively. MATERIALS AND METHODS: From March 1999 to February 2003, 54 patients, older than 65 years, of Jensen type 4 intertrochanteric fractures of the femur treated by DCS were included. The relationship between the structual integrity of lateral buttress measured by proximal-medial fragment angle (PMFA) and postoperative neck-shaft angle, penetrating length of lag screw, the sliding length and incidence of fixation loss were evaluated. RESULTS: Among 38 patients of group II (PMFA above 50 degree), 6 cases (15.8%) including 4 cases of cutting out of lag screw from femoral head, 1 case of nonunion and 1 case of excessive extrusion of lag screw failed radiologically. But there was no fixation loss case in 16 cases of group I (PMFA 50 and below 50). The neck-shaft angle in last follow-up was 138.1 degree in group I and 132.1 in group II. The sliding length of lag screw was 7.0 mm in group I and 12. 5 mm in group II (p<0.05). CONCLUSION: Preoperative evaluation of intactness of lateral buttress measured by proximal-medial fragmentary angle is an useful method in treatment of Jensen type 4 intertrochanteric fractures treated by DCS in elderly patients.