S Knob: Innovation Projection
Handrims in Wheelchair for
Patients with Tetraplegia
Suroj Jonglumsam*, Saowaluk Jantharakasamjit*, Thanitta Thanakiatpinyo**, Amnart
Duangtrakoon***
*Division of Occupational Therapy, Department of Rehabilitation Medicine, Faculty of Medicine Siriraj Hospital,
Mahidol University,** Department of Rehabilitation Medicine, Faculty of Medicine Siriraj Hospital, Mahidol
University, *** Occupational Therapy Unit, Ofce of The Director of Vajira Hospital, Faculty of Medicine Vajira
Hospital, Navamindradhiraj University.
Siriraj Medical Bulletin 2021; 14(2): 90-95
Abstract
Propelling wheelchair in patients with tetraplegia will help them engage in social
activities but they are not able to propel the wheelchair by themselves. This also affects them
to perform the activities of daily living, social participation, and their mental health. The
wheelchair with a projection pushrims will help propel the wheelchair easily, but this type
of wheelchair is very expensive. Therefore, we invented the “S Knob” which can be installed
around the handrim of the wheelchair for the patients. It’s not expensive, easy to install, and
the patients or their family can install it by themselves at home. After installing S Knobs
on the handrims, the participant with spinal cord injury can propel the wheelchair straight
forward, backward, turn right-left and turn 360 degrees by themselves. Ninety percent of
the patients are satised with this innovation, collected by satisfaction survey form. This
innovation also decreases the cost of buying an expensive projection pushrims. However,
this innovation cannot help the patient with tetraplegia propel the wheelchair on slopes or
rough terrain, so his caregiver has to help in this part to prevent the injury from propelling
the wheelchair.
Keywords: wheelchair; button around hand rim; tetraplegia
Correspondence to: Saowaluk Jantharakasamjit
E-mail: saowalukoat@gmail.com
Received: 17 February 2021
Revised: 22 March 2021
Accepted: 23 March 2021
http://dx.doi.org/10.33192/Simedbull.2021.20
Review Article
90  14  2 . - . 2564
S Knob:  
 
 
 
*, *,  **,  ***
*    ,
**   , ***
  
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


91
Siriraj Medical Bulletin
92 ี่� 14 ฉั่� 2 เม.ย - มิ.ย 2564
Original Article







* 


































93
Siriraj Medical Bulletin

















7







  








 5 5 5 4 2 2
Left 5 4 4



7
































 
  
  


 


 




1
94 ี่� 14 ฉั่� 2 เม.ย - มิ.ย 2564
Original Article



































     

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
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
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
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
















95
Siriraj Medical Bulletin





















