Do bone geometric properties of the proximal femoral diaphysis reflect loading history, muscle properties, or body dimensions?
Abstract Objectives: The aim of this study was to investigate activity‐induced effects from bone geometric properties of the proximal femur in athletic vs nonathletic healthy females by statistically controlling for variation in body size, lower limb isometric, and dynamic muscle strength, and cross‐sectional area of Musculus gluteus maximus. Methods: The material consists of hip and proximal thigh magnetic resonance images of Finnish female athletes (N = 91) engaged in either high jump, triple jump, soccer, squash, powerlifting, endurance running or swimming, and a group of physically active nonathletic women (N = 20). Cross‐sectional bone geometric properties were calculated for the lesse…
The relationship between loading history and proximal femoral diaphysis cross-sectional geometry
Objectives We investigated the relationship between loading history and bone biomechanical properties used in physical activity reconstructions. These bone properties included bone bending and torsional strength (J), cortical area (CA), the direction of the major axis (theta angle), and element shape ratios determined from cross sections of standardized bone length. In addition, we explored the applicability of anatomically determined cross sections. Methods Our material consisted of hip and proximal thigh magnetic resonance images of Finnish female athletes (N = 91) engaged in high-jump, triple-jump, endurance running, swimming, power-lifting, soccer and squash; along with a group of activ…
The cross-sectional area of the gluteus maximus muscle varies according to habitual exercise loading: Implications for activity-related and evolutionary studies.
Greater size of the gluteus maximus muscle in humans compared to non-human primates has been considered an indication of its function in bipedal posture and gait, especially running capabilities. Our aim was to find out how the size of the gluteus maximus muscle varies according to sports while controlling for variation in muscle strength and body weight. Data on gluteus maximus muscle cross-sectional area (MCA) were acquired from magnetic resonance images of the hip region of female athletes (N=91), and physically active controls (N=20). Dynamic muscle force was measured as counter movement jump and isometric knee extension force as leg press. Five exercise loading groups were created: hig…
Effect of fall direction on the lower hip fracture risk in athletes with different loading histories : A finite element modeling study in multiple sideways fall configurations
Physical loading makes bones stronger through structural adaptation. Finding effective modes of exercise to improve proximal femur strength has the potential to decrease hip fracture risk. Previous proximal femur finite element (FE) modeling studies have indicated that the loading history comprising impact exercises is associated with substantially higher fracture load. However, those results were limited only to one specified fall direction. It remains thus unclear whether exercise-induced higher fracture load depends on the fall direction. To address this, using magnetic resonance images of proximal femora from 91 female athletes (mean age 24.7 years with >8 years competitive career) and …
Exercise loading history and femoral neck strength in a sideways fall: A three-dimensional finite element modeling study
Over 90% of hip fractures are caused by falls. Due to a fall-induced impact on the greater trochanter, the posterior part of the thin superolateral cortex of the femoral neck is known to experience the highest stress, making it a fracture-prone region. Cortical geometry of the proximal femur, in turn, reflects a mechanically appropriate form with respect to habitual exercise loading. In this finite element (FE) modeling study, we investigated whether specific exercise loading history is associated with femoral neck structural strength and estimated fall-induced stresses along the femoral neck. One hundred and eleven three-dimensional (3D) proximal femur FE models for a sideways falling situ…
Ricci-flow based conformal mapping of the proximal femur to identify exercise loading effects.
AbstractThe causal relationship between habitual loading and adaptive response in bone morphology is commonly explored by analysing the spatial distribution of mechanically relevant features. In this study, 3D distribution of features in the proximal femur of 91 female athletes (5 exercise loading groups representing habitual loading) is contrasted with 20 controls. A femur specific Ricci-flow based conformal mapping procedure was developed for establishing correspondence among the periosteal surfaces. The procedure leverages the invariance of the conformal mapping method to isometric shape differences to align surfaces in the 2D parametric domain, to produce dense correspondences across an…
Impact loading history modulates hip fracture load and location : A finite element simulation study of the proximal femur in female athletes
Sideways falls impose high stress on the thin superolateral cortical bone of the femoral neck, the region regarded as a fracture-prone region of the hip. Exercise training is a natural mode of mechanical loading to make bone more robust. Exercise-induced adaptation of cortical bone along the femoral neck has been previously demonstrated. However, it is unknown whether this adaption modulates hip fracture behavior. The purpose of this study was to investigate the influence of specific exercise loading history on fall-induced hip fracture behavior by estimating fracture load and location with proximal femur finite element (FE) models created from magnetic resonance images (MRI) of 111 women w…