Effect of proximal femur nail anti-rotation on unstable intertrochanteric fractures: A prospective observational study

Objective:To assess the effect of proximal femur nail anti-rotation on the functional and radiological outcome of unstable intertrochanteric fractures.Methods:This prospective observational study was conducted in the orthopedic department of a tertiary care hospital.Altogether 86 patients with unstable intertrochanteric fractures treated with proximal femur nail anti-rotation between January 2010 and January 2015 were included.Patients were followed in the outpatient clinic at regular intervals after discharge to assess the radiological union of fractures and complications.The functional outcomes were evaluated after 2 years by Harris hip score.Results:All patients achieved a radiological union of fractures after a mean duration of 24.6 weeks.The follow up showed 23 complications(systemic and local).Eight patients developed urinary tract infections,and three patients developed chest infections,two patients had screw cut-out,one patient had knee stiffness,one patient developed superficial surgical site infection,and four patients developed varus collapse and shortening subsequently.The two year follow up showed that 69(80.2%)patients had an excellent and good functional outcome according to Harris hip score.Conclusions:With lower complication rates,proximal femur nail is a valid and reasonable option especially in treating unstable intertrochanteric fractures.

Proximal Femur Bionic Nail (PFBN): A Panacea for Unstable Intertrochanteric Femur Fracture

With the aging population,intertrochanteric femur fracture in the elderly has become one of the most serious public health issues and a hot topic of research in trauma orthopedics.Due to the limitations of internal fixation techniques and the insufficient mechanical design of nails,the occurrence of complications delays patient recovery after surgical treatment.Design of a proximal femur bionic nail(PFBN)based on Zhang’s N triangle theory provides triangular supporting fixation,which dramatically decreases the occurrence of complications and has been widely used for clinical treatment of unstable intertrochanteric femur fracture worldwide.In this work,we developed an equivalent biomechanical model to analyze improvement in bone remodeling of unstable intertrochanteric femur fracture through PFBN use.The results show that compared with proximal femoral nail antirotation(PFNA)and InterTan,PFBN can dramatically decrease the maximum strain in the proximal femur.Based on Frost’s mechanostat theory,the local mechanical environment in the proximal femur can be regulated into the medium overload region by using a PFBN,which may render the proximal femur in a state of physiological overload,favoring post-operative recovery of intertrochanteric femur fracture in the elderly.This work shows that PFBN may constitute a panacea for unstable intertrochanteric femur fracture and provides insights into improving methods of internal fixation.