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Table 1 Prosthetic suspension, control and overall prosthesis related observations

From: Case-study of a user-driven prosthetic arm design: bionic hand versus customized body-powered technology in a highly demanding work environment

Task/issue TBI (iLimb) CBPA (body-powered)
Carry items for more than 8m distanceb. Frequent drops due to postural interference [90, 91, 140]ab. No problem.
Pulling or lifting bodies (typically 60–90 kg). Excessive pull displaced or detached skin-electrode contact [92] and strained stump skin mechanically [72]. Socket (suspension) fit was not sufficiently robust for heavy pulling or holdinga. No problem.
Sweat issuesb. Electrode control loss after 10 min with shortest examinations of 30 min [84, 85]a. Electrode rash with sweat exposure, slow healing over  6 weeks [98100]a. No problem other than having to pour out sweat occasionally.
Typingb [216]. Shoulder and elbow pain due to (a) distal weight / center of COG [87] and (b) compensatory posture [178] required to fit awkward hand shape into typing position. Skin abrasions and blisters on stump skin due to friction occured already over a few hours [72]b. No problem. Weight and design of split hook, prehensor and wrist optimal for highly repetitive hard push operations. Ideal posture with Hosmer model 5 series hooks.
Meetings, presentationsb. The prosthesis attracted unwarranted and irritated attention, also by being unreliable, which in part was seen a consequence of limb positioning effect [90, 91], myoelectrode dysfunction [84, 85] and grip problems (see Table 2). The CBPA’s wrist unit allowed for rapid swaps of the terminal device (split hook) against a prosthetic hand. such as the Becker hand. As this device worked flawlessly with regard to grip reliability and no noise, it did not distract others nearly as much.
Overall reliability. Battery [95], sweat, socket fit, electrode function (“bad hand day”) [84, 85], software issues and hand grip control issues lead to a rating as insufficient reliability for the job and tasks evaluated here. Occasional repair necessary after wear down of cable or supporting structures, with a frequency of about once every 9 to 12 months.
Cost for operating or running the deviceb. Each glove around 300-700 USD, lasting up to 10 min even under light work conditions. Device at 80,000 USD. For a 3 year period of use with 12 weeks of on-call work, 10 hours per day with 7 days a week, assuming that a glove withstands 3 hours of actual work usage (which it does not), an hourly hardware cost of 198 USD/ hour is obtained. No glove or weardown issues; split hook claws can be covered with silicone tubing if required (a few cents per fitting). Prosthetic arm at 6,000 USD, custom shoulder anchor at 3,000 USD, custom wrist at 1,500 USD, prosthetic split hook or prehensor at 400 to 1,200 USD. Becker hand 650 USD. For the same 3 year period of use, hourly hardware cost of about 5 USD results (about 2% of TBI).
  1. aNot acceptable / not negotiable in work environment
  2. bRated just as good or better without prosthesis