- no kinetic differences among grasps, whether considered individually or grouped by the number of fingers on the barrel.
- when grasps were grouped according to the thumb position, the adducted grasps exhibited higher mean grip and axial forces.
- Grip forces were generally similar across the different grasps.
- Kinetic differences resulting from thumb position seemed to have no effect on speed and legibility.
Reference: Schwellnus H, Carnahan H, Kushki A, Polatajko H, Missiuna C, Chau T. Writing forces associated with four pencil grasp patterns in grade 4 children. Am J Occup Ther. 2013 Mar;67(2):218-27. doi: 10.5014/ajot.2013.005538.