The purpose of this retrospective study was to evaluate the effects of Dyna Locking Trochanteric (DLT) nail (U & I Corporation 529-1, Yonghyun-dong, Uijungbu Kyunggi-Do, Korea 480-050) in 31-A1 and 31-A2 intertrochanteric femur fractures. Eighty-seven patients (63 female and 24 male, mean age 77 years) were treated. The mean duration of follow-up was 16.6 +/- 3.1 months (range, 12-24 months). There were 36 cases of 31-A1 and 51 cases of 31-A2 fractures. The duration of surgery, fluoroscopy screening time, the blood loss, the hospital stay, the tip-apex distance were significantly less in the 31-A1 fracture group compared with the 31-A2 fracture group (p < 0.001). Cut-out was observed in 13 patients (14.9%) above 80 years old with 31-A2 fractures. Especially in elderly patients with unstable 31-A2 fractures, the wedge wing on the neck screw does not work properly. Therefore further biomechanical investigations and also prospective clinical studies with larger series are needed to improve the device.