Pilot Validation of a Computal Seated Human Model Using an Instrumented Chair

Sitting-acquired deep tissue injuries (SADTI) are the most serious type of pressure ulcers. In order to investigate the ethiology of SADTI a new approach is under development. A musculo-skeletal model can predict forces at different seated positions and thereby find an optimum position where the risk of SADTI is minimized. This study focuses on validation of a musculo-skeletal model developed in the AnyBody Modeling System for predicting reaction forces on a wheelchair. A Wheelchair with forcemeasuring equipment was developed, an experiment was conducted, and the experimental results were compared with the predictions of the computational model. The results show that the model predicted changes in reaction forces due to changes in the chair posture well. It was concluded that the experimental approach is satisfactory and more experiments should be carried out to completely validate the computational model.

[1]  B. Nigg,et al.  Biomechanics of the musculo-skeletal system , 1995 .

[2]  C J Snijders,et al.  Shear stress measured on beds and wheelchairs. , 1997, Scandinavian journal of rehabilitation medicine.

[3]  D. Walsh,et al.  Impact of sitting time on seat-interface pressure and on pressure mapping with multiple sclerosis patients. , 2005, Archives of physical medicine and rehabilitation.

[4]  D. Hobson.  Comparative effects of posture on pressure and shear at the body-seat interface. , 1992, Journal of rehabilitation research and development.

[5]  Stephen Sprigle,et al.  Effect of seat inclination on seated pressures of individuals with spinal cord injury. , 2004, Physical therapy.

[6]  L. By,et al.  Skin stress and blood flow in sitting paraplegic patients. , 1984, Archives of physical medicine and rehabilitation.

[7]  Michael Damsgaard,et al.  Analysis of musculoskeletal systems in the AnyBody Modeling System , 2006, Simul. Model. Pract. Theory.

[8]  Michael Damsgaard,et al.  The seated human - biomechanical modeling/ergonomic design , 2004 .

[9]  C G Cayten,et al.  A new pressure ulcer risk assessment scale for individuals with spinal cord injury. , 1996, American journal of physical medicine & rehabilitation.

[10]  Michael Clark,et al.  Science and practice of pressure ulcer management , 2006 .

[11]  R. Patterson,et al.  Sitting forces and wheelchair mechanics. , 1990, Journal of rehabilitation research and development.

[12]  L. A. Christensen,et al.  Basisbog i Medicin og Kirurgi , 2007 .

[13]  V. C. Roberts,et al.  The effect of shear forces externally applied to skin surface on underlying tissues. , 1993, Journal of biomedical engineering.

[14]  R. Bode,et al.  Medical complications during acute rehabilitation following spinal cord injury--current experience of the Model Systems. , 1999, Archives of physical medicine and rehabilitation.

[15]  Amit Gefen,et al.  The biomechanics of sitting‐acquired pressure ulcers in patients with spinal cord injury or lesions , 2007, International wound journal.

[16]  G A Hoek van Dijke,et al.  Influence of shear on skin oxygen tension. , 1994, Clinical physiology.

[17]  Tamara Reid Bush,et al.  Support force measures of midsized men in seated positions. , 2007, Journal of biomechanical engineering.

[18]  R. Patterson,et al.  continuous sitting force measurements with differ- ent support surfaces in the spinal cord injured and able-bodied , 1991 .

[19]  L. Bennett,et al.  Shear vs pressure as causative factors in skin blood flow occlusion. , 1979, Archives of physical medicine and rehabilitation.

[20]  R Roaf,et al.  The causation and prevention of bed sores. , 2006, Journal of tissue viability.