Development and Psychometric Validation of Capacity Assessment of Prosthetic Performance for the Upper Limb (CAPPFUL).

OBJECTIVES: (1) To develop a performance-based measure for adult upper limb (UL) prosthetic functioning through broad (ie, overall performance) and functional domain-specific (eg, control skills) assessment of commonplace activities; (2) to conduct initial psychometric evaluation of the Capacity Assessment of Prosthetic Performance for the Upper Limb (CAPPFUL). DESIGN: Internal consistency of CAPPFUL and interrater reliability for task, functional domain, and full-scale (sub)scores among 3 independent raters were estimated. Known-group validity was examined comparing scores by amputation level. Convergent validity was assessed between CAPPFUL and 2 hand dexterity or function tests; discriminant validity was assessed against self-reported disability. SETTING: Six prosthetic rehabilitation centers across the United States. PARTICIPANTS: Subjects (N=60) with UL amputation using a prosthesis. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Not applicable. RESULTS: Interrater reliability was excellent for scoring on the task, domain, and full-scale scores (intraclass correlation coefficients=.88-.99). Internal consistency was good (α=.79-.82). Generally, subjects with higher UL amputation levels scored lower (worse) than subjects with lower UL amputation levels. CAPPFUL demonstrated strong correlations with measures of hand dexterity or functioning (rs=-.58 to .72) and moderate correlation with self-reported disability (r=-.35). CONCLUSIONS: CAPPFUL was designed as a versatile, low-burden measure of prosthesis performance for any UL functional prosthetic device type and any UL amputation level. CAPPFUL assesses overall performance and 5 functional performance domains during completion of 11 tasks that require movement in all planes while manipulating everyday objects requiring multiple grasp patterns. Psychometric evaluation indicates good interrater reliability, internal consistency, known-group validity, and convergent and discriminant validity.

Predictors of retention and attrition in a study of an advanced upper limb prosthesis: implications for adoption of the DEKA Arm.

PURPOSE: The purpose was to identify factors associated with completion of the VA home study of the DEKA Arm. Design and methodological procedures used: Differences between groups were examined using chi-square and t-tests. A multivariable logistic regression model predicting completion was generated and odds ratios (OR) for significant variables calculated. Post-hoc analysis was performed to plot the receiver operating characteristics (ROC) curve. RESULTS: Participants who completed were more likely to be prosthesis users at study onset (p = .03), and less likely to have a history of musculoskeletal problems (p = .047). There were no statistically significant differences between groups who completed and those who did not in gender, race, veteran status, age, body mass index (BMI), weight, height, musculoskeletal pain at baseline, satisfaction with current prosthesis, type of prosthesis, or months of prosthesis use. Two variables, prosthesis use and history of musculoskeletal problems were significant at p < .10. The area under the curve (AUC) accuracy index was 0.78. CONCLUSIONS: We considered completion of the home use study a reasonable proxy for participant willingness to adopt the device; and believe that findings can be extrapolated to guide DEKA Arm prescription recommendations. Participants most likely to complete the study were already using a personal prosthesis, and without pre-existing musculoskeletal problems. Implications for rehabilitation Data from the VA Study of the DEKA Arm were analysed to determine which factors were associated with likely successful adoption of the DEKA Arm. Participants most likely to complete the study were those who already using a personal prosthesis, and those without pre-existing chronic or re-occurring musculoskeletal problems. This information may be useful when attempting to identify and target the most appropriate candidates for DEKA Arm prescription.

Movement quality of conventional prostheses and the DEKA Arm during everyday tasks.

BACKGROUND: Conventional prosthetic devices fail to restore the function and characteristic movement quality of the upper limb. The DEKA Arm is a new, advanced prosthesis featuring a compound, powered wrist and multiple grip configurations. OBJECTIVES: The purpose of this study was to determine if the DEKA Arm improved the movement quality of upper limb prosthesis users compared to conventional prostheses. STUDY DESIGN: Case series. METHODS: Three people with transradial amputation completed tasks of daily life with their conventional prosthesis and with the DEKA Arm. A total of 10 healthy controls completed the same tasks. The trajectory of the wrist joint center was analyzed to determine how different prostheses affected movement duration, speed, smoothness, and curvature compared to patients' own intact limbs and controls. RESULTS: Movement quality decreased with the DEKA Arm for two participants, and increased for the third. Prosthesis users made slower, less smooth, more curved movements with the prosthetic limb compared to the intact limb and controls, particularly when grasping and manipulating objects. CONCLUSION: The effects of one month of training with the DEKA Arm on movement quality varied with participants' skill and experience with conventional prostheses. Future studies should examine changes in movement quality after long-term use of advanced prostheses. Clinical relevance Movement quality with the DEKA Arm may depend on the user's previous experience with conventional prostheses. Quantitative analyses are needed to assess the efficacy of novel prosthetic devices and to better understand how to train people to use them effectively.

Self-reported and performance-based outcomes using DEKA Arm.

Mechanical properties of the DEKA Arm and associated engineering innovations are easy to observe. What is less clear is how these advances translate into functional benefits for the user with amputation. Study aims were to (1) quantify outcomes including dexterity, performance of daily activities, and prosthetic skill and spontaneity of users of the DEKA Arm and (2) compare outcomes when using the DEKA Arm with scores using the existing prosthesis. This was a quasi-experimental study. Descriptive analyses examined outcomes by DEKA Arm configuration level. Of the 39 subjects fit with a DEKA Arm, 32 were trained in use and completed end-of-study testing. Data from 26 prosthetic users were used to compare outcomes using existing prostheses with outcomes with the DEKA Arm. Dexterity and activity performance with the DEKA Arm varied by amputation level (p < 0.01). Self-reported function and number of activities performed using the prosthesis were similar across levels. Comparisons with existing prostheses showed the effect on dexterity varied by level. Activity performance and spontaneity of prosthetic use improved for users of the shoulder configuration level, while use of the prosthesis to perform activities and perceived difficulty performing self-selected tasks improved for all levels.