Although humans have a large repertoire of potential movements, gait patterns tend to be stereotypical and appear to be selected according to optimality principles such as minimal energy. When applied to dynamic musculoskeletal models such optimality principles might be used to predict how a patient's gait adapts to mechanical interventions such as prosthetic devices or surgery. In this paper w...

Astride jumps in an aerobic dance routine has produced a "runner's" stress fracture.

BACKGROUND Stress fractures and other musculoskeletal injuries are major sources of morbidity among female military trainees. Several risk factors have been postulated, particularly pre-existing fitness, usually assessed with post-entry run time for ≥ 1.0 mile. PURPOSE Physical fitness is not formally evaluated prior to Army entry. If a valid and simple test that identified women at increased...

When the shale gas reservoir is fractured, stress shadows can cause reorientation of hydraulic fractures and affect complexity. To reveal variation shadow with perforation spacing, numerical model between different spacing was simulated by extended finite element method (XFEM). The analyzed from two centers, fracture path, ratio length to spacing. simulations showed that rock at centers always ...

In a survey of 75 dancers (mean age, 24.3 years) in four professional ballet companies, we found that the prevalence of scoliosis was 24 percent and that it rose with increases in age at menarche. Fifteen of 18 dancers (83 percent) with scoliosis had had a delayed menarche (14 years or older), as compared with 31 of 57 dancers (54 percent) without scoliosis (P less than 0.04). The dancers with ...

A method is described whereby fractures of the neural arch similar to those in spondylolysis are produced experimentally. The forces, bending moments and displacements required to initiate the fractures are given; The mechanical aspects in the aetiology of spondylolysis are explained by a simplified two-dimensional force analysis.

background fractures of the knee account for about 6% of all trauma admissions. while its management is mostly focused on fracture treatment, it is not the only factor that defines the final outcome. objectives this study aimed to study objective and subjective outcomes after proximal tibial versus distal femoral fractures in terms of knee instability and health-related quality of life. patient...