Analysis Of Risk Factors Of PFNA In The Treatment Of Fracture Fixation Of Intertrochanteric Fracture Of Femur

Objective: To review the failure of fixing intertrochanteric fracture with proximal femoral nail anti-otation(PFNA),and to investigate the risk factors of the failure.Method: A retrospective study of all proximal femoral fractures treated with the PFNA in Wei Hai Municipal Hospital from January 2012 to January 2016 was performed.Patient demographic data was obtained from hospital records.Patients included in the study were divided into two groups according to the success of the internal fixation device: internal fixation group(group A)and internal fixation failure group(group B).Fractures were classified according to AO/ OTA for the Study of Internal Fixation.Fracture reduction,thickness of lateral wall,type of lateral wall,obtained collo-diaphyseal angle,and blade position within the head(tip-apex distance and Cleveland zone)were recorded from the intraoperative and immediate postoperative radiographs.Postoperative radiographs obtained in the routine treatment of patients were studied for review looking primarily for the risks of each possible factors.The data of the measurement and the age and sex of the patients were analyzed and statistically analyzed with SPSS.Result: One hundred forty patients could be followed up clinically.The mean continuous follow-up was 20.3 months(6-46),There were nine surgical implant related failures(6.4%).The single most common mode of failure was cut-out in five cases(55.6%).The thickness of the lateral wall of the femur trochanter in the patients with internal fixation failure was 21.7 mm,which was significantly lower than that in the internal fixation group(27.5 mm),the difference was statistically significant,and it is the most important risk factor for surgical failure.Tip-apex distance in the 20-30 mm no case of internal fixation failure,Tip-apex distance is the second factor in the failure of internal fixation;Obtained collo-diaphyseal angle <130 patients failure rate was significantly higher than the angle> 130 patients,the difference between the two groups(P <0.05).There was also a significant difference in the statistical analysis of patients with poor fracture reduction and poor quality.After performing the Mann–Whitney U test a statistically significant difference between the two groups was seen(internal fixation failure either did or did not occur)for both Tip-apex distance,Obtained collo-diaphyseal angle and thickness of lateral wall.There was no significant difference between the groups for age sex and Cleveland quadrant as a result of Pearson's Chi squared test.Internal fixation failure factors are: proximal femur thickness,fracture reduction quality,helical blade in the femoral head position and obtained collo-diaphyseal angle,The logistic regression test showed that thickness of lateral wall was the strongest factor for internal fixation failure complications;the second most important factor was TAD.Conclusion: Thickness of lateral wall of proximal femur,TAD>30mm or TAD<20mm,Obtained collo-diaphyseal angle,poor fracture reduction may be intertrochanteric fracture of the femur by PFNA treatment of internal fixation failure related factors,.Age sex and Cleveland quadrant were not attributed to the failure of PFNA fxation.