1. The patient must have a source of power which can be harnessed.
2. An analysis of a patient's needs should include special attention to the essential motions to be replaced (grasp, pronation, supination, elbow flexion and extension, internal and external rotation of the shoulder, and shoulder flexion).
3. The brace must be light, comfortable to wear, and, if possible, should be so constructed that the patient can put it on or take it off by himself.
4. The necessary working area for the desired activity should be known and properly planned for.
5. Arm braces at the present stage of their development can replace many normal activities but not all of them. They should be planned to accomplish specific tasks.
6. Arm braces must work from a stable base on the patient's body.
7. Harnessing must supply a satisfactory range of motion and power for the activities desired.
8. A brace must be relatively simple in operation so that its value is worth the patient's effort in making it function.
9. The braces must be simple and sturdy enough so that frequent breakdowns do not occur and frequent adjustments are unnecessary.
Other important factors that should always be considered are:
1. The patient must desire help and must he willing to put up with minor inconveniences in the appliance and its appearance.
2. Careful analysis of the patient's desires and potentials by physician, physical therapist, occupational therapist, and prosthetist before final prescription will assure a better functioning appliance.
3. Proper training in the use of the appliance by a qualified occupational therapist or physical therapist is desirable upon delivery of the brace or apparatus.
4. The prosthetist must be willing to devote time for the final careful adjustment of equipment, for often a change from one-quarter to one-half of an inch in a suspension point will mean success or failure.
5. The manufacturer of functional braces for the arm and the fitter should have a knowledge of upper-extremity function. They should be thoroughly familiar with harnessing of artificial arms and the equipment involved in their use; they should be able to think in terms of motion rather than in terms of statics and positioning.