Functional Importance of a Powered Multifunction Wrist Protocol

Measuring the function of upper limb prostheses is challenging and requires multiple test formats. A toolkit of functional outcome tests recommend by the Academy of Prosthetics and Orthotics ULPOM committee will be used to measure functional effectiveness of prosthetic treatment will be used as the primary outcome measure. The outcome measures to evaluate prosthesis use includes both quantitative and qualitative testing of prosthesis control and functional performance.

An objective test of unilateral hand function that can be used to evaluate functionality of passive, mechanical, or myoelectric hands without bias to type [31]. Movement of abstract objects (classified into six prehension patterns) and activities of daily living are timed by the subject. Scores are compared to a normalized, able-bodied control score of 100.

A timed test that evaluates gross manual dexterity. Small (1-inch) blocks are moved one at a time from one side of a box to the other over a wooden partition. The final score is the number of blocks transferred in 1 minute, typically averaged over three trials. For this test, only opening and closing of the terminal device is required, although subjects with transradial amputations do typically use compensatory movements. It is possible that a 2-DOF wrist may move inadvertently and impair performance on this task. As a result, we would view either an improvement or no change in this score to be a positive finding.

A standardized test of manual dexterity that evaluates hand function during performance of seven hand-related tasks using common items such as cards, cans, paper clips, and coins [32]. Subjects are evaluated by the time required to complete each task

An observational assessment tool that measures the subject's ability to control a myoelectric hand. The ability to control gripping, holding, releasing, and coordinating 30 items is scored on a 4-point capability scale. The prosthetic hand is used in an active assist or passive support role. Rasch analysis is used to convert capability ratings to a single measure of each subject's functional ability. Both Ms Turner and Dr. Miller are trained to complete this assessment.

A 19- item, self-reported measure of an individual's ability to perform self-care and upper limb-based daily living tasks (e.g. button shirt, tie shoelaces) using a 5-point scale [35]. Rasch analysis of the questionnaire ratings is used to calculate an overall measure of each subject's functional ability.

A questionnaire that asks patients to list up to five tasks they have difficulty with and rate the difficulty on an 11-point numerical scale [36]. Difficulty ratings can be averaged for each participant.

A test of prosthetic function that requires the user to move three clothespins from a vertical bar to a horizontal bar (thereby requiring use of the elbow, terminal device, and wrist rotator). This test has been in use by CBM as a measure of prosthesis function for over a decade.

For the TAC Test, participants must move the virtual hand into a target posture and hold it there for a preset period of time. The TAC Test can require movement of from one to all available degrees of freedom (e.g. hand grasp plus wrist motion). Results are measured in terms of classification accuracy, completion rate, completion time, and path efficiency. This test will be used to ensure that subjects have satisfactory PR control over all DOFs prior to starting their home trial.