Does hip morphology correlate with proximal femoral fracture type?

Purpose: To determine if boney morphology influences the anatomic location of hip fractures in elderly patients. Methods: All patients with hip fractures between 2008 and 2012 who had hip radiographs taken prior to the fracture were reviewed. Fractures were classified as intracapsular or extracapsular and hip morphology was measured on the pre-fracture x-rays. Hip morphology was determined by alpha angle, lateral central edge angle, acetabular index, neck-shaft angle, hip axis length, femoral neck diameter, Tönnis classification for hip osteoarthritis (OA) and the presence of a crossover sign. Results: 148 subjects (78.4% female, age 83.5 years) with proximal femur fractures were included. 44 patients (29.7%) had intracapsular fractures and 104 (70.3%) had extracapsular fractures. 48% of patients had previous hip fractures on the contralateral side and 74.6% had the same type of fracture bilaterally. The rates of bilateral intracapsular and extracapsular fractures were similar (33.7% vs. 40.9% respectively, p = 0.39). Extracapsular fractures had a statically significant higher neck-shaft angle, a shorter hip axis length, a narrower femoral neck diameter and a higher grade of Tönnis classification of OA ( p = 0.04, 0.046, 0.03, 0.02 respectively). Acetabular coverage and the proximal femoral head-neck junction, which were evaluated by lateral centre-edge angle (LCEA), acetabular index and the presence of a crossover sign, did not correlate with fracture type. The alpha angle > 40° had a statistically significant higher likelihood for extracapsular fractures ( p = 0.013). Conclusions: Acetabular coverage and proximal femoral head-neck junction morphology, were found to partially correlate with the location of hip fractures and do not fully elucidate fracture type susceptibility.

The Influence of Acetabular Morphology on Prediction of Proximal Femur Fractures Types in an Elderly Population

Introduction The role of proximal femur morphology to the development of certain proximal femur fracture types both femoral neck and trochanteric fractures has been observed. However, the relavance of acetabular morphology to the development of proximal femur fractures is not extensively questioned. Therefore the aim of the study was to determine whether there is a correlation between acetabular morphology and pathogenesis of 2 different hip fracture types after low energy trauma. Methods This retrospective study includes 60 cases (41 women, 19 men) with a proximal femoral fracture after a low energy trauma between July 2012 and December 2014. Acetabular depth and acetabular index were measured on pelvic radiographs. Neck shaft angle, hip axis length and cortical index were measured on pelvic computed tomography scans. All measurements were performed on the contralateral hip. Results Mean age was 77.56 ± 8.99 years (range 61-92 years). No statistically significant difference was found with regard to neck shaft angle, acetabular depth or cortical index measurements between patients with femoral neck fracture and patients with trochanteric femoral fractures (p>0.05). Acetabular index measurement was higher (p = 0.001) and hip axis length measurement was lower (p = 0.001) in trochanteric fracture group as compared to femoral neck fracture. Conclusions The rate of trochanteric femur fractures is higher in patients with high acetabular index, whereas the rate of femoral neck fractures is higher in patients with increased hip axis length.