Objective To compare the biomechanical characteristics of the less invasive stabilization system (LISS) and the dynamic condylar screw (DCS) in the fixation of subtrochanteric fractures of the femur so as to provide theoretical basis for choosing internal fixator in clinical application. Methods Twelve cadaveric human femurs (35-50 years old) were selected with similar proximal femur, excluding deformities, fractures, and other lesions. The twelve femur specimens were randomly divided into 2 groups, 6 specimens per group. An 1 cm gap of osteotomy model was made in the proximal femur up to 1 cm below the lesser trochanter to simulate a comminuted subtrochanteric fracture of femur, and the distal end was embedded with denture acrylic and liquid for denture acrylic. Fracture was fixed by LISS in group A, and was fixed by DCS in group B. The specimens were fixed on Instron-8874 servo-hydraulic mechanical testing machine in a single-leg standing position, and the axial compression test and dynamic fatigue test were carried out to compare the compressive strength and the strain distribution at both sides of the fracture line. Results Axial compression test: the strain values of the 2 strain gauges in group A were significantly smaller than those in group B (P lt; 0.01); the vertical down displacement of the femoral head in group A was significantly smaller than that in group B (P lt; 0.01) under the same load; when the load was 600 N, the axial rigidity of group A was (209.06 ± 18.63) N/mm, which was significantly higher than that of group B [(65.79 ± 7.26) N/mm] (t=3.787, P=0.004). Dynamic fatigue test: the vertical down displacement of the femoral head in group A was significantly smaller than that in group B in the same cyclic loading cycle (P lt; 0.01); when the vertical down displacement of the femoral head was 0.5 mm, the force and the cyclic loading cycles in group A were significantly larger than those in group B (P lt; 0.01). Conclusion LISS, which has good mechanical stability, can meet the requirements for subtrochanteric fracture of femur fixation in biomechanics and anatomical structures. It can be proven that the LISS internal fixator is firmer than the DCS internal fixator by biomechanical comparison.
ObjectiveTo compare the effectiveness between open reduction and closed reduction of pediatric subtrochanteric fractures using elastic stable intramedullary nailing (ESIN). MethodsBetween January 2010 and January 2014, 22 children with subtrochanteric fractures were treated by ESIN internal fixation combined with hip cast fixation, and the clinical data were retrospectively reviewed. Closed reduction was used in 12 cases (group A) and miniopen reduction in 10 cases (group B). There was no significant difference in gender, age, sides, fracture causes, type of fracture, complications, and time from injury to operation between 2 groups (P>0.05). The operation time, intraoperative blood loss, fracture healing time, and complications were recorded and compared between 2 groups, the limb function was evaluated according to the Flynn et al. outcome score. ResultsThe intraoperative blood loss of group A was significantly less than that of group B, but the operation time of group A was significantly longer than that of group B (P<0.05). All the patients were followed up 12-36 months (mean, 14.9 months). There was no major complications in the other patients of both groups except 1 patient having delayed wound healing in group B. There was no significant difference in fracture healing time between 2 groups (t=-1.006, P=0.327). Inverted angle of 10° and shortened limb of 1.8 cm were observed in 1 case of group A, and sagittal plane angle of 15° and shortened limb of 2 cm in 1 case of group B. There was no abnormal walking and function of hip and knee activity at last follow-up. According to the Flynn et al. outcome score, the results were excellent in 8 cases and good in 4 cases in group A, and were excellent in 6 cases and good in 4 cases in group B, showing no significant difference between 2 groups (χ2=0.041, P=0.956). ConclusionBoth closed and open fracture reduction using ESIN have satisfactory outcomes for treating pediatric subtrochanteric fractures. A mini-open reduction should be selected intraoperatively if closed reduction proves to be difficult.
Objective To discuss the effectiveness of intramedullary nail fixation with selective cable wiring in the treatment of ipsilateral femoral neck fracture and subtrochanteric fracture. Methods Between June 2012 and December 2015, a total of 19 patients with ipsilateral femoral neck fracture and subtrochanteric fracture underwent closed reduction of femoral neck fracture and intramedullary nail fixation combined with selective cable wiring. There were 5 males and 14 females with a median age of 52 years (range, 35-77 years). The cause of injury included traffic accident injury in 17 cases and falling injury in 2 cases. According to Garden classification for femoral neck fractures, 7 cases were rated as type Ⅱ, 8 as type Ⅲ, and 4 as type Ⅳ. Femoral subtrochanteric fractures were classified by Seinsheimer classification, with 9 cases as type Ⅱ, 5 as type Ⅲ, 3 as type Ⅳ, and 2 as type V. The interval from injury to operation ranged from 2 to 7 days with an average of 3.7 days. Results The operation time was 58-125 minutes (mean, 82.4 minutes) and the intraoperative blood loss was 225-725 mL (mean, 289.5 mL). All incisions achieved healing by first intention and no early complication such as infection was observed. All patients were followed up 12-18 months (mean, 13.9 months). At 1 month after operation, the tip apex distance was 9-23 mm (mean, 15.2 mm). All patients achieved bone union with the healing time of 18-42 weeks (mean, 27.4 weeks). One case of hip varus and femoral neck re-displacement (femoral neck shaft angle was 122°) occurred at 3 months after operation, which achieved bone union at 42 weeks after operation. Five patients complained of postoperative pain with the visual analogue scale (VAS) score of 1-3 (mean, 1.8), which did not influence normal life. A total of 16 patients recovered preoperative hip function. During follow-up, no fracture nonunion, femoral head necrosis, implant failure, screw cut-out, and loosening of cable wiring was observed. The Harris hip score (HSS) was 72-92 (mean, 82.8) at last follow-up and 15 patients (78.9%) achieved good hip function. Conclusion Intramedullary nail fixation combined with selective cable wiring was effective in the treatment of ipsilateral femoral neck fracture and subtrochanteric fracture.
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.
Objective To compare the effectiveness of lower extremity axial distractor (LEAD) and traction table assisted closed reduction and intramedullary nail fixation in treatment of femoral subtrochanteric fracture. Methods The clinical data of 117 patients with subtrochanteric fracture of femur treated by closed reduction and intramedullary nail fixation between May 2012 and May 2022 who met the selection criteria were retrospectively analyzed. According to the auxiliary reduction tools used during operation, the patients were divided into LEAD group (62 cases with LEAD reduction) and traction table group (55 cases with traction table reduction). There was no significant difference in baseline data, such as gender, age, injured side, cause of injury, fracture Seinsheimer classification, time from injury to operation, and preoperative visual analogue scale (VAS) score, between the two groups (P>0.05). Total incision length, operation time, intraoperative blood loss, fluoroscopy frequency, closed reduction rate, fracture reduction quality, fracture healing time, weight-bearing activity time, and incidence of complications, as well as hip flexion and extension range of motion (ROM), Harris score, and VAS score at 1 month and 6 months after operation and last follow-up were recorded and compared between the two groups. Results There were 14 cases in the LEAD group from closed reduction to limited open reduction, and 43 cases in the traction table group. The incisions in the LEAD group healed by first intention, and no complication such as nerve and vascular injury occurred during operation. In the traction table group, 3 cases had perineal crush injury, which recovered spontaneously in 1 week. The total incision length, operation time, intraoperative blood loss, fluoroscopy frequency, and closed reduction rate in the LEAD group were significantly better than those in the traction table group (P<0.05). There was no significant difference in the quality of fracture reduction between the two groups (P>0.05). Patients in both groups were followed up 12-44 months, with an average of 15.8 months. In the LEAD group, 1 patient had delayed fracture union at 6 months after operation, 1 patient had nonunion at 3 years after operation, and 1 patient had incision sinus pus flow at 10 months after operation. In the traction table group, there was 1 patient with fracture nonunion at 15 months after operation. X-ray films of the other patients in the two groups showed that the internal fixator was fixed firmly without loosening and the fractures healed. There was no significant difference in fracture healing time, weight bearing activity time, incidence of complications, and postoperative hip flexion and extension ROM, Harris score, and VAS score at different time points between the two groups (P>0.05). ConclusionFor femoral subtrochanteric fracture treated by close reduction and intramedullary nail fixation, compared with traction table, LEAD assisted fracture reduction can significantly shorten the operation time, reduce intraoperative blood loss and fluoroscopy frequency, reduce incision length, effectively improve the success rate of closed reduction, and avoid complications related to traction table reduction. It provides a new method for good reduction of femoral subtrochanteric fracture.