Different Morphometric and Densitometric Parameters Predict Cervical and Trochanteric Hip Fracture: The EPIDOS Study

Abstract

We used an experimental software measuring the hip axis length (HAL) and bone mineral density (BMD) in specific regions of the lower and upper part of the femoral neck on dual-energy X-ray absorptiometry scans. To determine whether these parameters were significant predictors of the type of hip fracture, we measured 167 healthy women (controls), 24 women with trochanteric, and 42 women with cervical hip fractures within the EPIDOS prospective cohort. EPIDOS is a multicenter prospective study on risk factors for hip fracture performed in 7575 elderly women living at home, aged 75-95 and conducted in five French centers (Amiens, Lyon, Montpellier, Paris, Toulouse). Measurements were performed on data acquired at baseline before the occurrence of fracture. In the cervical fracture group, HAL was significantly longer than in controls (94.2 vs. 92.3, p ‫؍‬ 0.03), and the associated odds ratio (OR) adjusted for age, weight, and total femoral neck BMD was significant (OR ‫؍‬ 1.64, 95% confidence interval [CI] 1.06 -2.55). In contrast, HAL was not significantly different from controls in the trochanteric fracture group. Femoral neck diameter was not a predictor of fracture. The upper and lower femoral neck BMD was lower in the trochanteric fracture group than in controls, and both measurements predicted trochanteric femoral neck fracture. In contrast, the prediction of cervical femoral neck fracture was enhanced by measuring only the upper part of the femoral neck (OR ‫؍‬ 2.79 vs. 1.97 for the total femoral neck) while BMD of the lower part was not different from controls. Hip axis length is a predictor of femoral neck fracture. Femoral neck BMD distribution is different between cervical and trochanteric fractures. These results support the hypothesis of a different pathophysiological mechanism between the two types of hip

In vivo discrimination of hip fracture with quantitative computed tomography: Results from the prospective European Femur Fracture Study (EFFECT)

“…(49) Trochanteric fractures also have been shown to be associated with increased mortality when compared with cervical fractures, and this could not be explained by differences in age or comorbidity. (4) Since there is evidence in both in vitro (14,15,42,47,50) and in vivo (3,30) studies that cervical and trochanteric fractures have different risk factors, we compared densitometric and geometric variables between the two subgroups and analyzed hip fracture discrimination separately for each subgroup. Compared with cervical fracture cases, we found lower DXA aBMD and QCT BMD values in trochanteric fracture cases, but differences were not statistically significant.…”

“…These results are in agreement with current knowledge that women with trochanteric fractures have a more severe and generalized low bone density involving particularly the trabecular component, with lower aBMD in the trochanteric region and lumbar spine. (51) Cervical fractures seem to depend more on proximal femur or pelvic geometry (such as a larger femoral neck shaft angle or a longer hip axis length in cervical fractures (2,3,30,50) ) combined with focal bone loss. (51) In the EPIDOS study, aBMD values of novel upper and lower femoral neck subregions were lower in trochanteric fractures than in controls, but prediction of cervical fractures was improved by measuring aBMD only in the upper subregion of the femoral neck.…”

“…(51) In the EPIDOS study, aBMD values of novel upper and lower femoral neck subregions were lower in trochanteric fractures than in controls, but prediction of cervical fractures was improved by measuring aBMD only in the upper subregion of the femoral neck. (3) It is well established that bone density measurements made at the specific fracture site provide stronger fracture risk prediction. (2,17,18,30,51) Using statistical parametric mapping, Li and colleagues (45) demonstrated recently the existence of a small region between the femoral neck and head with significantly lower BMD values in cervical compared with trochanteric fracture cases.…”

“…Assessment of fracture risk is complicated additionally by the fact that there are major differences between patients with ORIGINAL ARTICLE J JBMR trochanteric-intertrochanteric fractures and cervical fractures. (2)(3)(4) For example, patients with trochanteric-intertrochanteric fractures have a more severe and generalized BMD deficit, bone geometry appears to play a lesser role, and morbidity is higher. (2)(3)(4) In clinical practice, the physician now can assess the risk of hip fracture for an individual patient from several clinical factors, which include age, weight, fracture after age 50 years, parental hip fracture, smoking status, alcohol intake, glucocorticoid therapy, and secondary causes of osteoporosis, with or without areal bone mineral density (aBMD).…”

“…(2)(3)(4) For example, patients with trochanteric-intertrochanteric fractures have a more severe and generalized BMD deficit, bone geometry appears to play a lesser role, and morbidity is higher. (2)(3)(4) In clinical practice, the physician now can assess the risk of hip fracture for an individual patient from several clinical factors, which include age, weight, fracture after age 50 years, parental hip fracture, smoking status, alcohol intake, glucocorticoid therapy, and secondary causes of osteoporosis, with or without areal bone mineral density (aBMD). (5,6) These variables can be pooled into the recent World Health Organization (WHO) FRAX tool (www.shef.ac.uk/FRAX/) or similar algorithms to calculate a 10-year fracture risk.…”