ObjectiveTo investigate the effectiveness of closed or limited open reduction and intramedullary nail fixation in the treatment of Seinsheimer type Ⅴ subtrochanteric fracture.MethodsBetween May 2014 and July 2018, 36 patients with Scinsheimer type Ⅴ subtrochanteric fractures were treated with closed or limited open reduction and intramedullary nail fixation. There were 25 males and 11 females with an age of 23-86 years (mean, 55.8 years). The cause of injury included falling in 19 cases, traffic accident in 9 cases, falling from height in 7 cases, and heavy object injury in 1 case; all were fresh closed injuries. The interval between injury and operation was 1-14 days (mean, 6.8 days). There were 18 cases of closed reduction and 18 cases of limited open reduction during the operation. Seventeen cases were fixed with femoral reconstruction intramedullary nail, 5 with InterTan long nail, 14 with lengthened proximal femoral nail anti-rotation, and 7 cases were assisted with auxiliary steel wire binding. After operation, through X-ray film and clinical follow-up, the fracture reduction and maintenance status, internal fixation position, and fracture healing were judged; the range of motion, walking ability, and complications of hip joint were observed, and the function of hip joint was evaluated according to Merle d’Aubigne Postel hip joint scoring standard.ResultsAll the incisions of medullary operation healed by first intention, and no vascular, nerve injury, or infection occurred. All patients were followed up 12-24 months, with an average of 14.2 months. Among the 36 patients, 1 patient received revision surgery due to varus displacement of femoral head and screw penetration at 2 months after closed reduction, with poor recovery of hip function. X-ray film re-examination showed that the fractures of the other 35 patients healed after 9-15 months, with an average of 11.5 months. During follow-up, there was no complication such as internal fixation failure, fracture redisplacement, bone nonunion or malunion, and deep vein thrombosis of lower extremity occurred. The function of hip joint recovered well, and the patients could walk and squat normally without affecting daily life or work. At last follow-up, according to Merle d’Aubigne Postel hip joint scoring standard, 28 cases were rated as excellent, 4 cases as good, 3 cases as fair, and 1 case as poor, the excellent and good rate was 88.9%.ConclusionC-arm X-ray fluoroscopic closed or limited open reduction and intramedullary nail fixation for the treatment of Seinheimer Ⅴ type subtrochanteric fracture, if necessary, with the aid of auxiliary steel wire binding, it has the advantages of less blood supply destruction at the fracture end, satisfactory reduction, firm fixation, and early rehabilitation training, with definite effectiveness.