AS2 study

INTERVENTION: Group 1 Investigational: Patients receiving a ZNN CM Asia with ASS technique. Group 2 Conventional Signature: Patients receiving a ZNN CM Asia without ASS (conventional) technique. CONDITION: Trochanteric fracture of the femur PRIMARY OUTCOME: The maintenance rate of immediate post‐operative reduction position versus 2‐3 week post‐operative SECONDARY OUTCOME: Surgery time; Effect of post‐operative reduction position (AP3XML3 classification) against reduction positon at the operation; Effect for CT assessment due to fracture type at the traumatism; Effect for CT assessment due to post‐operation reduction position; Effect for CT assessment with or without ASS; Safety evaluation INCLUSION CRITERIA: Eligible for intramedullary nailing. Fracture type is classified as 3‐partB or 4‐part fracture in 3D‐CT classification (Nakano), and combination with a subtype P in lateral classification (Ikuta) at preoperative CT assessment.(In the case of classified in X‐ray at preoperative: Classified as Type 4 or Type 5 in Jensen classification, and combination of subtype P in lateral classification (Ikuta)) Japanese Male or female over 20 years of age Primary closed intertrochanteric fracture of the femur Subjects willing to return for follow‐up evaluations.