Biomedical Engineering Reference
In-Depth Information
depends on a number of diverse considerations (Kelley, Pangilinan et al., 2009):
•
Amputation level.
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Contour of the residual limb.
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Expected function of the prosthesis.
•
Cognitive function of the patient.
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Vocation of the patient (desk job or manual labor).
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Patient interests (e.g., hobbies).
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Cosmetic importance of the prosthesis.
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Financial resources of the patient.
10.8.1 Actuation and Control of Upper Limb Prostheses
For upper limb prostheses, gross motions of the shoulder or the upper arm and sometimes
of the chest are generally captured by a harness connected to a terminal device (TD)
such as a hook or hand, as illustrated in Figure 10-12. For above-the-elbow amputees,
double- or even triple-cable harnesses may be required with one to control the hook, a
second to restore elbow flexion, and a third to lock it in place.
For patients to be able to control a body-powered prosthesis, they must be capable
of one or more of the following gross body movements: glenohumeral flexion, scapular
abduction or adduction, shoulder depression and elevation, or chest expansion. Addition-
ally, they need sufficient muscle power and range of motion to provide effective actuation
of the TD.
FIGURE 10-12
Shoulder harness
controlled
articulated hook.
