A Biomechanical Model of the Human Spinal System

Dietrich, Marek; Kędzior, Krzysztof; Zagrajek, T.

doi:10.1243/pime_proc_1991_205_257_02

Cited by 33 publications

(17 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The abdominal wall was represented by the elements located at the cylinder periphery, and the abdominal cavity was represented by the elements located at the cylinder centre. Young's moduli of 1 MPa and 0.01 MPa and Poisson coefficients of 0.2 and 0.45 were chosen from the literature (SUNDARAM and FENS, 1977; UEYOSHI and SHIMA, 1985;DIETRICH et al, 1991;MARRAS and SOMMERICH, 1991) for the abdominal wall and cavity, respectively.…”

Section: Methodsmentioning

confidence: 99%

Biomechanical modelling of orthotic treatment of the scoliotic spine including a detailed representation of the brace-torso interface

Périé

Aubin

Lacroix

et al. 2004

Med. Biol. Eng. Comput.

View full text Add to dashboard Cite

As part of the development of new modelling tools for the simulation and design of brace treatment of scoliosis, a finite element model of a brace and its interface with the torso was proposed. The model was adapted to represent one scoliotic adolescent girl treated with a Boston brace. The 3D geometry was acquired using multiview radiographs. The model included the osseo-ligamentous structures, thoracic and abdominal soft tissues, brace foam and shell, and brace-torso interface. The simulations consisted of brace opening to include the patient's trunk followed by brace closing. To validate the model, the resulting geometry was compared with the real in-brace geometry, and the resulting contact reaction forces at the brace-torso interface were compared with the equivalent forces calculated from pressure measurements made on the in-brace patient. Differences between coronal equivalent and reaction forces were less than 7N. However, sagittal reaction forces (47N) were computed on the abdomen, whereas negligible equivalent forces were measured. The simulated geometry presented partially reduced coronal Cobb angles (1-4 degrees), over-corrected sagittal Cobb angles and maximum deformation plane (5 degrees), completely corrected coronal shift, and sagittal shift and rib humps that were not corrected. This study demonstrated the feasibility of a new approach that represents the load transfer from the brace to the spine more realistically than does the direct application of forces.

show abstract

Section: Methodsmentioning

confidence: 99%

Biomechanical modelling of orthotic treatment of the scoliotic spine including a detailed representation of the brace-torso interface

Périé

Aubin

Lacroix

et al. 2004

Med. Biol. Eng. Comput.

View full text Add to dashboard Cite

show abstract

“…A number of optimization and EMG driven models have been used to estimate the muscle forces in various lifting conditions. Many of these models do not properly account for the nonlinear passive resistance and/or complex geometry/loading/dynamics (i.e., inertia and damping) of the spine [16,26,35,93]. In addition, many are simplified in not considering dynamic equilibrium equations simultaneously in all directions and at all levels.…”

Section: Introductionmentioning

confidence: 99%

Analysis of squat and stoop dynamic liftings: muscle forces and internal spinal loads

2006

View full text Add to dashboard Cite

Despite the well-recognized role of lifting in back injuries, the relative biomechanical merits of squat versus stoop lifting remain controversial. In vivo kinematics measurements and model studies are combined to estimate trunk muscle forces and internal spinal loads under dynamic squat and stoop lifts with and without load in hands. Measurements were performed on healthy subjects to collect segmental rotations during lifts needed as input data in subsequent model studies. The model accounted for nonlinear properties of the ligamentous spine, wrapping of thoracic extensor muscles to take curved paths in flexion and trunk dynamic characteristics (inertia and damping) while subject to measured kinematics and gravity/ external loads. A dynamic kinematics-driven approach was employed accounting for the spinal synergy by simultaneous consideration of passive structures and muscle forces under given posture and loads. Results satisfied kinematics and dynamic equilibrium conditions at all levels and directions. Net moments, muscle forces at different levels, passive (muscle or ligamentous) forces and internal compression/shear forces were larger in stoop lifts than in squat ones. These were due to significantly larger thorax, lumbar and pelvis rotations in stoop lifts. For the relatively slow lifting tasks performed in this study with the lowering and lifting phases each lasting~2 s, the effect of inertia and damping was not, in general, important. Moreover, posterior shift in the position of the external load in stoop lift reaching the same lever arm with respect to the S1 as that in squat lift did not influence the conclusion of this study on the merits of squat lifts over stoop ones. Results, for the tasks considered, advocate squat lifting over stoop lifting as the technique of choice in reducing net moments, muscle forces and internal spinal loads (i.e., moment, compression and shear force).

show abstract

“…To overcome the foregoing shortcomings, linear finite element models along with optimization algorithms have been developed and used to evaluate muscle recruitment, internal loads, and stability margin (Dietrich et al, 1991;Gardner-Morse et al, 1995;GardnerMorse and Stokes, 1998;Gardner-Morse, 1995, 2001). A simplified geometrical model of the spine with rotational degrees-of-freedom and nonlinear stiffness properties along with EMG-assisted optimization approach was used to evaluate muscle forces and stability margin in various tasks (Cholewicki and McGill, 1996).…”

Section: Introductionmentioning

confidence: 99%

Model and in vivo studies on human trunk load partitioning and stability in isometric forward flexions

Arjmand

Shirazi‐Adl

2006

Journal of Biomechanics

162

View full text Add to dashboard Cite

A Biomechanical Model of the Human Spinal System

Cited by 33 publications

References 6 publications

Biomechanical modelling of orthotic treatment of the scoliotic spine including a detailed representation of the brace-torso interface

Biomechanical modelling of orthotic treatment of the scoliotic spine including a detailed representation of the brace-torso interface

Analysis of squat and stoop dynamic liftings: muscle forces and internal spinal loads

Model and in vivo studies on human trunk load partitioning and stability in isometric forward flexions

Contact Info

Product

Resources

About