The focus of this study is to conduct a clinical study in individuals with transradial amputations to compare function using a 1-DOF or 2-DOF wrist. All prostheses will be attached to a single DOF Otto Bock hand and controlled using a pattern recognition system equivalent to the Coapt system. This study will enable the investigator to quantify the relative functional value of powered wrist flexion during both in-laboratory testing and home use. In addition, the investigators will address the effectiveness of different hand-wrist combinations to enhance patient-centered clinical decision making.
The primary objective of this project is to evaluate the functional importance of a multi function wrist compared to a single degree of freedom wrist. This will be accomplished through in laboratory testing and an 8-week home trial. The first aim will involve in-laboratory functional performance testing with a 1-DOF or a 2-DOF wrist and a one degree of freedom hand. Changes in performance will be assessed with multiple outcome measures that include both quantitative and qualitative testing of prosthesis control and functional performance. The second aim will determine how a 2-DOF wrist impacts control and home use of a one degree of freedom hand. Subjects will compete an 8 week home based trial. Participants will be instructed to complete a written home log of activities and electronic logging usage data will also be collected for each experimental condition. The investigators hypothesize that adding a wrist flexion/extension module to a wrist rotation module and a single-DOF terminal device will provide significant improvements in function for transradial amputees.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
NONE
Enrollment
9
A commercially available and registered with the FDA prosthesis equipped with a powered single-degree of freedom wrist and powered hand.
An experimental, non FDA registered prosthesis equipped with a multi function wrist and a powered hand.
Shirley Ryan AbilityLab
Chicago, Illinois, United States
Academy of Prosthetics and Orthotics ULPOM committee toolkit of outcome measures to record change of prosthetic performance
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.
Time frame: Baseline and 8 weeks for Condition A; Baseline and 8 weeks for Condition B
SHAP: Southampton Hand Assessment Procedure; a clinically validated hand function test to assess the effectiveness of upper limb prostheses.
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.
Time frame: Baseline and 8 weeks for Condition A; Baseline and 8 weeks for Condition B
Modified Box and Blocks Test of Manual Dexterity
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.
Time frame: Baseline and 8 weeks for Condition A; Baseline and 8 weeks for Condition B
Jebsen-Taylor Hand Function Test
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
Time frame: Baseline and 8 weeks for Condition A; Baseline and 8 weeks for Condition B
Assessment of Capacity for Myoelectric Control (ACMC)
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.
Time frame: Baseline and 8 weeks for Condition A; Baseline and 8 weeks for Condition B
Orthotics and Prosthetics User Survey - Upper Extremity Function Status
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.
Time frame: Baseline and 8 weeks for Condition A; Baseline and 8 weeks for Condition B
Patient Specific Functional Scale
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.
Time frame: Baseline and 8 weeks for Condition A; Baseline and 8 weeks for Condition B
Clothespin Relocation Test
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.
Time frame: Baseline and 8 weeks for Condition A; Baseline and 8 weeks for Condition B
Virtual Testing: Target Achievement Control Test
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.
Time frame: 2 days
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.