A pilot study was conducted to test and compare
efficiency and functional capabilities of a 3D-printed prosthetic arm
and a commercially available manufactured myoelectric hand to determine
if 3D-printed upper-limb prostheses could provide a cost-effective
alternative. The results and observations made by the researchers
suggested the myoelectric prosthesis was more practical and efficient
than the 3D-printed device. The study was published in the July 2017 issue of the Journal of Prosthetics & Orthotics (JPO).
A
Box and Blocks Test was used to assess the efficiency of a myoelectric
i-limb (Touch Bionics, Livingston, Scotland) and a 3D-printed Limbitless
Arm (Limbitless Solutions, Orlando, Florida). The research team
designed a quasi-experimental, static group comparison trial with 24
able-bodied participants, 14 men and ten women who were healthy, were
right hand–dominant, and had a mean age of 26.1 years (± 4.2 years). Two
custom devices, to which the two prostheses attached distally, were
created to accommodate the participants. The prostheses were tested by
the participants over two visits with a two-week crossover period.
The
mean number of blocks moved with the 3D-printed device was
significantly lower than with the myoelectric prosthesis. For trial 1,
the mean was 8.4 ± 3.6 blocks with the 3D-printed device versus 12.9 ±
3.3 with the i-limb. For trial 2, the mean was 8.3 ± 3.6 blocks with the
3D-printed device versus 13.8 ± 4.1 with the i-limb. Furthermore, the
researchers found that the mean number of blocks moved improved when
using the myoelectric prosthesis versus the 3D-printed hand by 53.6
percent in trial 1 and 66.3 percent in trial 2.
The researchers
obtained similar findings after completing separate analyses by gender.
For men, in trial 1 the mean was 9.1 ± 3.3 blocks with the 3D-printed
device versus 12.9 ± 3.7 with the myoelectric prosthesis; in trial 2,
the mean was 9.6 ± 3.2 blocks with the 3D-printed device versus 14.1 ±
4.7 with the myoelectric prosthesis. For women, in trial 1 the mean was
7.5 ± 3.9 blocks with the 3D-printed device versus 12.8 ± 2.9 with the
myoelectric prosthesis; in trial 2, the mean was 6.3 ± 3.4 blocks with
the 3D-printed device versus 13.4 ± 3.2 with the myoelectric prosthesis.