The Load on Lumbar Disks in Different Positions of the Body

Nachemson, Alf

doi:10.1097/00003086-196600450-00014

Cited by 487 publications

(205 citation statements)

References 0 publications

Supporting

Mentioning

177

Contrasting

Unclassified

Order By: Relevance

“…And it is notorious that one of the main actions of the abdominal muscles is the spine flexion, however, this kind of movement lead to a lot of stress at the vertebral body, and in case the person presents bone fragility, a fracture may happen. Early in 1966 Nachemson (55) detected that spine flexion was the position that most stressed the vertebral bodies. Later in 1984, Sinaki and Mikkelsen (56) figured out that from a group of osteoporotic postmenopausal women that performed spine flexions as an exercise routine, 89% presented vertebral fractures after a period of two years.…”

Section: Precaution During Exercisesmentioning

confidence: 99%

Physical exercise and osteoporosis: effects of different types of exercises on bone and physical function of postmenopausal women

Moreira

Oliveira

Lirani-Galvão

et al. 2014

Arq Bras Endocrinol Metab

162

117

View full text Add to dashboard Cite

Physical exercise is an important stimulus for osteoporosis prevention and treatment. However, it is not clear yet which modality would be better to stimulate bone metabolism and enhance physical function of postmenopausal women. This review paper aims to summarize and update present knowledge on the effects of different kinds of aquatic and ground physical exercises on bone metabolism and physical function of postmenopausal women. Moderate to intense exercises, performed in a high speed during short intervals of time, in water or on the ground, can be part of a program to prevent and treat postmenopausal osteoporosis. Mechanical vibration has proven to be beneficial for bone microarchitecture, improving bone density and bone strength, as well as increasing physical function. Although impact exercises are recognized as beneficial for the stimulation of bone tissue, other variables such as muscle strength, type of muscle contraction, duration and intensity of exercises are also determinants to induce changes in bone metabolism of postmenopausal women. Not only osteoanabolic exercises should be recommended; activities aimed to develop muscle strength and body balance and improve the proprioception should be encouraged to prevent falls and fractures. Arq Bras Endocrinol Metab. 2014;58(5):514-22

show abstract

Section: Precaution During Exercisesmentioning

confidence: 99%

Physical exercise and osteoporosis: effects of different types of exercises on bone and physical function of postmenopausal women

Moreira

Oliveira

Lirani-Galvão

et al. 2014

Arq Bras Endocrinol Metab

162

117

View full text Add to dashboard Cite

show abstract

“…Gravity loads of each vertebral level were derived from the work of Schultz and co-workers [25]. These gravitational loads were amplified based on the equations of Nachemson [20] in order to integrate the muscular component for a subject in an upright standing position. This approach of estimation of spinal and muscle loads was preferred, since resulting combined gravity and muscle forces are obtained from measurements of intradiscal pressures, which are closely related to vertebral growth plates activity.…”

Section: Biomechanical Model Of Bone Growth Modulationmentioning

confidence: 99%

Biomechanical simulations of the spine deformation process in adolescent idiopathic scoliosis from different pathogenesis hypotheses

Villemure

Aubin

Dansereau

et al. 2004

European Spine Journal

View full text Add to dashboard Cite

IntroductionAdolescent idiopathic scoliosis (AIS) is a complex threedimensional (3D) anomaly of the spine involving lateral deviations in the frontal plane, modifications of the sagittal profile, spinal torsion and transverse plane deformations [16,21,23]. There is still no generally accepted scientific theory for its etiology [7,16,21,23]. The pathogenesis of AIS is not clearly defined regarding either how Abstract It is generally recognized that progressive adolescent idiopathic scoliosis (AIS) evolves within a selfsustaining biomechanical process involving asymmetrical growth modulation of vertebrae due to altered spinal load distribution. A biomechanical finite element model of normal thoracic and lumbar spine integrating vertebral growth was used to simulate the progression of spinal deformities over 24 months. Five pathogenesis hypotheses of AIS were represented, using an initial geometrical eccentricity (gravity line imbalance of 3 mm or 2°rotation) at the thoracic apex to trigger the self-sustaining deformation process. For each simulation, regional (thoracic Cobb angle, kyphosis) and local scoliotic descriptors (axial rotation and wedging of the thoracic apical vertebra) were evaluated at each growth cycle. The simulated AIS pathogeneses resulted in the development of different scoliotic deformities. Imbalance of 3 mm in the frontal plane, combined or not with the sagittal plane, resulted in the closest representation of typical scoliotic deformities, with the thoracic Cobb angle progressing up to 39°(26°when a sagittal offset was added). The apical vertebral rotation increased by 7°t owards the convexity of the curve, while the apical wedging increased to 8.5°(7.3°with the sagittal eccentricity) and this deformity evolved towards the vertebral frontal plane. A sole eccentricity in the sagittal plane generated a non-significant frontal plane deformity. Simulations involving an initial rotational shift (2°) in the transverse plane globally produced relatively small and nontypical scoliotic deformations. Overall, the thoracic segment predominantly was sensitive to imbalances in the frontal plane, although unidirectional geometrical eccentricities in different planes produced three-dimensional deformities at the regional and vertebral levels, and their deformities did not cumulate when combined. These results support the hypothesis of a prime lesion involving the precarious balance in the frontal plane, which could concomitantly be associated with a hypokyphotic component. They also suggest that coupling mechanisms are involved in the deformation process.

show abstract

“…Or comme le confirment un assez grand nombre de recherches sur la position assise et plus particulièrement sur les opératrices de machine à coudre, cette position est accompagnée de nombreux problèm es physiologiques et musculo-squelettiques (Sjogaard et al 1988 ;Vihma, Nurminen et Mutanen 1982 ;Serratos-Perez et Mendiola-Anda 1993 ;Vézina, Tierney et Messing 1992 ;Punnett et al 1985 ;Sokas, Spiegelman et Wegman 1989 ;Brisson, Vinet et Vézina 1989 ;Blader et al 1991 ;Li, Haslegrave et Corlett 1995 ;Laville 1985). Certains, comme la pression exercée sur les disques intervertébraux, dans la région lombaire, sont mêmes plus importants en position assise que debout (Grandjean et Hunting 1977 ;Nachemson 1966 ;Yates et Karwowski 1987, 1992. Il ne faudrait donc pas croire que l'ancienne position assise occupée par les couturières dans le système traditionnel n'entraîne pas des maux importants.…”

Section: Resultsunclassified

Assis ou debout ?

Brossard¹

1998

Relations industrielles

View full text Add to dashboard Cite

The Load on Lumbar Disks in Different Positions of the Body

Cited by 487 publications

References 0 publications

Physical exercise and osteoporosis: effects of different types of exercises on bone and physical function of postmenopausal women

Physical exercise and osteoporosis: effects of different types of exercises on bone and physical function of postmenopausal women

Biomechanical simulations of the spine deformation process in adolescent idiopathic scoliosis from different pathogenesis hypotheses

Assis ou debout ?

Contact Info

Product

Resources

About