Evaluation of a Myoelectrical Arm for Transradial Amputation in Functional Activities

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In this paper, the authors designed an experimental protocol to evaluate a home-based training program developed to increase the motor performance of a patient with transradial myoelectric prosthesis during daily life.

Despite the authors’ efforts and the interesting study, I reckon this paper is not suitable for publication in its current status and it needs some edits.

Here are my comments:

 

-I do not understand why in the Introduction the authors gave emphasis to the distinction between upper and lower limb. I suggest removing this section and paying attention exclusively to the case of upper limb amputation;

- I suggest adding a paragraph at the end of the Introduction where the structure of the paper is presented;

-I suggest adding the inclusion/exclusion criteria adopted for the participant’s enrolment;

-I suggest adding more information on the clinical status of the patient such as the time since the amputation and the etiology;

-I do not understand the duration of treatment and thus the months between the two evaluation sessions;

-I have appreciated the use of two appendices reporting the details of the training program and evaluation protocol. Nonetheless, I reckon some details has to be reported in the main body, too: otherwise, it is difficult to understand the following sections. In addition, the text has to report the rationale behind the choice of the performed activities;

-I suggest checking the sampling frequencies reported at the beginning of page 4. It seems the EMG signals were acquired with a sampling rate of 40 Hz. Maybe, the order of the frequencies is not correct;

- I suggest reporting the monitored muscles in the “Evaluation protocol” subsection and the rationale behind their choice;

- I suggest modifying figure 1 removing the subfigure on the right;

- I do not understand the number of repetitions performed by the authors for each session. Is it just 2? If yes, why only 2 repetitions that is a very low value;

-Which kind of normalization was executed for kinematic, kinetic and myoelectric signal? Please, report it;

-I suggest strongly revising figures from 2 and 6 reporting mean and standard deviations signals and not only the mean value;

-I suggest replacing Table I and II with some plots (e.g., multiple boxplot and barplot) that could strongly increase the readability of the paper;

-Although the authors stated the statistical analysis was not performed because of low number of samples, I suggest perform it and report the obtained results since statistical analysis is a crucial feature for a scientific paper published in a peer-reviewed journal.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This study investigated the effects of training programs to adapt to a myoelectric arm in performing the activities of daily life. One user performed it, and some potentials were reported in balance, muscle efficiency, and functionality. I believe the experiments is valuable as the one with the transradial amputation was recruited, but the manuscript needs to be improved.

 

In the introduction, check here: “Lastly, there is lack of scientific evidence regarding the outcomes of myoelectric am … “.

 

I think the participant’s prior experience should be reported in detail, like frequency of use of the body-powered prosthesis, type of tasks that she does in daily life, and skill level.

 

The design of the training program should be clarified. While several factors are considered, there is no detailed theoretical framework. Also, how this approach differs from existing prosthetic training programs should be explained.

 

What was reference value used for EMG normalization?

 

The explanation of trunk and shoulder angles should be clarified. Specifically, what reference frame was used for these angles, and how were changes in movement interpreted in terms of functional improvement? I also suggest adding a figure to illustrate the key angles analyzed in the study.

 

The study evaluates movement kinematics and task performance but does not directly assess user satisfaction. Since prosthesis movement characteristics likely impact cognitive load and user experience, it would be useful to discuss how this could be measured directly. For example, EEG signals have been used to assess user satisfaction in response to EMG-controlled robotic hand movement [1]. Expanding the discussion with relevant examples would be helpful.

[1] https://doi.org/10.3390/s23010277

 

Author Response

Please see the attachment. 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Article review

Title: Evaluation of a Myoelectrical Arm for Transradial Amputation in Functional Activities

Dear Researchers,

It is with great pleasure that I extend my sincerest congratulations to you for your exemplary work in this research endeavor. It is imperative for the scientific community to transcend the confines of the laboratory and extend its contributions to the betterment of society and the enhancement of the quality of life for citizens. In this regard, I would like to offer some observations on the arduous efforts you have made to ensure the comprehension of your article by a broader audience.

Introduction

1. A) “Lastly, there is lack of scientific evidence regarding the outcomes of myoelectric am training program, as there is lack of standardized methods recommended for training with myoelectric arm with multi-grip modes [10].”

1^st Comment: Please add the "r" to the word "am".

1. B) In the third page of the document, the objective of the research is articulated. It is stated therein that the prosthetic myoelectric arm was procured from a certified prosthetist and orthotist (CPO) at Medical Center Orthotics & Prosthetics (Silver Spring, MD, USA).

2^nd Comment: It is reasonable to hypothesize that the scientist in question has developed a unique technology for the purpose of prosthetic limb implantation. Given the assertion that a study with a larger sample size is being prepared, it is pertinent to inquire about the adaptability of the protocol in question. Specifically, it would be beneficial to ascertain whether the participating scientists and prosthetic limb insertion clinics are utilizing disparate technologies and methodologies. Alternatively, would the protocol be adapted to include a sample of patients treated by the same physician?

Methodology

1. C) 3^rd Comment: In the initial paragraph of the methodology, the term "participants" was utilized. Given the assertion in the abstract that there is only one participant, it would be advisable to replace the word "participants" with "participant."

Methodology participant

1. D) 4^th Comment: It is essential to determine whether a motor skill test was administered to the participant in question. Given the researcher's intention to expand the study's sample size, it would be prudent to implement a motor skill protocol. This would ensure the safety of the research process by allowing the researcher to predict the participant's ability to respond promptly and correctly to the administered tests.

 

Discussion

1. E) 5^th Comment: The author posits that the time to complete the task with the bottle cap increased by 0.06 seconds. This increase is hypothesized to be due to either the training process being ineffective or the assessment tasks not thoroughly examining the necessary range of trunk and shoulder movement in each axis of rotation to ascertain any improvement.The ineffectiveness of the process would logically extend to other assessments. The failure to adequately consider the necessary range of motion of the torso and shoulder in each axis of rotation to detect any improvement constitutes a significant limitation of the study, which necessitates further justification and evaluation to avoid similar errors in future research.It is imperative to provide a more thorough and substantiated argument to address this critical concern.

Ε) “The participant may have become more cognitively attuned to flexion as the muscle activation that opens the hand and may have translated that to more activation in the triceps during the post evaluation”.

“As data is collected from more participants, the Wil-coxon signed-rank test [24] will be utilized to compare baseline and post training data to determine if there is a significant change”.

“a standing desk will be utilized with minimal surface area as the testing platform to further reduce the interference on motion capture caused by surface reflection”.

“The participant needed to use her right hand to manually set the wrist unit to proper pronation/supination angle at the beginning of each task”.

6^th Comment: As previously mentioned, the aforementioned paragraphs represent the limitations of the research. It is beneficial to acknowledge these limitations so that they can be evaluated by other scientists and to avoid similar errors, if possible. It is therefore recommended that the discussion be reformulated and that a paragraph be added at the end that enumerates all the limitations. This will assist future research in understanding what to avoid.

1. F) “a standing desk will be utilized with minimal surface area as the testing platform to further reduce the interference on motion capture caused by surface reflection”.

7^th Comment: However, it must be acknowledged that a minimal surface area may impose undue stress on an individual acclimating to a prosthesis, potentially impeding the desired outcome of the evaluation.I would greatly appreciate your insights on this matter.

Conclusion

24. G) An outcome measure to note was the task completion which showed improvement on average for the tBBT task by 24.04 seconds, box lifting by 1.6 seconds, bottle pouring by 8.96 seconds, and pulley task by 8.4 seconds. However, the time for the bottle cap task increased slightly by 0.06 seconds.

8^th Comment: The aforementioned paragraph is reiterated in the text in its exact original form. In order to avoid redundancy, it would be advisable to rephrase it in a manner that maintains the same core meaning while employing different words, given that the content has already been established.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

In this paper, the authors designed an experimental protocol to evaluate a home-based training program developed to increase the motor performance of a patient with transradial myoelectric prosthesis during daily life.

This is the second version of the manuscript and its overall quality was improved.

Nonetheless, I have some additional revisions to suggest mainly regarding data normalization. Why did the authors not normalize myoelectric activity with respect to the Maximum Voluntary Contraction or the GRF with respect to the body weight?

Author Response

Please see the attachment.

Reviewer 2 Report

Comments and Suggestions for Authors

I have no further concerns.

Author Response

Thank the reviewer for reviewing our manuscript.