PONE-D-19-20223

Biomechanical Influence of Gait Patterns on Knee Joint: Kinematic & EMG analysis

PLOS ONE

Dear Ju seok Ryu,

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PLOS ONE

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This research was supported by a grant of the Korea Health Technology R&D Project through the Manuscript Click here to download Korea Health Industry Development Institute (KHIDI), funded by the Ministry 23 of Health & Welfare, Republic of Korea (grant number : HI18C1169)

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Partly

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: No

Reviewer #2: I Don't Know

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #1: Yes

Reviewer #2: No

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Dear corresponding Author thanks for your submission. Please check these comments:

- The age diffrence between the two groups is significant. How can you be sure that this different is not the cause of different walking style? It is a sample problem.

- Please can you show information how you measured the stride width? You mean the horizontal distance between two feet? Or the stride length, in some part of the paper it is not clear.

- The statistical approach is very simple and I don't think that it is correct to use the paired T-Test for the comparison of different way to walk in the same group. This kind of procedure is called "repeated measure" and so the statistical approach should be different. Usually some correction factors are used (such as Bonferroni). Please check this point with a statistic specialist just to be sure.

- The results in table 2 are difficult to understand. Please can you explain how the sistem works to measure the FTA in varus and valgus. Moreover the table 2 in not clear in terms of significance: there are two different symbols and it is not clear the comparison. Please modify.

- The legend of figure 1A is wrong. The platform used is not a force plate but a pressure plate with a sensorized matrix.

- From the results it is not clear how did you use the stride width parameter. It is a very very interesting parameter but there is no explanation of the modification of this parameter in differents gait style. In the discussion paragraph you speak about stride width (line 259) but no data are presented in the results.

- Line 281: which part of the results allow you to write this sentence?

- So the practical application of this paper, as you wrote in conclusion, is to suggest to walk with abducted legs because the higher muscular recruitment? Can you explain better this point? I understand that the muscle recruitment is higher for sure but the pain and discomfort as well. So it seems a strange suggestion.

Reviewer #2: This paper requires major revision. It is not coherent or methodologically sound (at least as described).

Putting aside the missing definite article in the title, the title itself is misleading, especially since they state in their discussion that they cannot make conclusions about knee OA.

The topic is poorly explained and background on both clinical and basic research is basically non-existent.

The hypotheses are vague, asserting weakness and its effect on gait and on the knee and on knee OA. They are not specific. Moreover, the argument for why this affects the knee rather than the hip is not stated clearly or convincingly. A causative effect is simply asserted and not explained in a way that makes it predictable.

There is no real discussion in the introduction of the role played by abductors in normal gait and how the different gaits really worked. Is it not the case, that the patterns of EMG are very predictable across gaits. So this is really a question of comparisons between LSS and control. But even then the results are reasonably predictable.

I need clearer hypotheses and clearer statements about why this data is being pursued, aside from that it hasn't been collected before.

The adducted gait is intense and un-natural. I can only envision it as a shuffle. I could use more description of this gait to justify its inclusion.

The choice of gaits leads to obvious associations. For example, it makes sense a priori that stride width would require more abductors. It also makes sense that stride width changes knee alignment.

How do you know you got EMG from lesser gluteals. I believe you, but would like to know how you verified that was the case in detail.

I have no idea why the EMG was normalized to QF. Please expain the logic for this. It doesn't make sense to me at this point. I also worry that some of the patient group has OA already and that QF weakness and OA are correlated. So this may lead to weir values.

Much of the discussion addresses complexities and contradicitions in the results. But these challenges are unexpected to the reader because they are are poorly laid out in the introduction.

The discussion does a more thorough job setting up the problem and much of it could have appeared in the intro. But also in the discussion we learn that the data necessary to test at least one of the hypotheses has not been collected. "Therefore, the causality between knee osteoarthritis and LSS cannot be drawn from this study." This was a purpose of the study.

Figure 4 seems to be mislabeled.

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Reviewer #1: No

Reviewer #2: No

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PONE-D-19-20223R1

Biomechanical Influence of Gait Patterns on Knee Joint: Kinematic & EMG analysis

PLOS ONE

Dear Dr. Ryu,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

==============================

ACADEMIC EDITOR: The issues raised by reviewer should be addressed adequately before considering the manuscript for pubblication. 

==============================

We would appreciate receiving your revised manuscript by Mar 22 2020 11:59PM. When you are ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter.

To enhance the reproducibility of your results, we recommend that if applicable you deposit your laboratory protocols in protocols.io, where a protocol can be assigned its own identifier (DOI) such that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). This letter should be uploaded as separate file and labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. This file should be uploaded as separate file and labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. This file should be uploaded as separate file and labeled 'Manuscript'.

Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out.

We look forward to receiving your revised manuscript.

Kind regards,

Riccardo Di Giminiani

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: (No Response)

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: (No Response)

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: (No Response)

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: (No Response)

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: (No Response)

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: 1) the age problem in the sample is still present

2) I know the sotfware you use and it doesn't measure the width, moreover it is not showed in the figure 1A as you write.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

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Reviewer #1: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files to be viewed.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email us at figures@plos.org. Please note that Supporting Information files do not need this step.

Biomechanical Influence of Gait Patterns on Knee Joint: Kinematic & EMG analysis

PONE-D-19-20223R2

Dear Dr. Ryu,

We are pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it complies with all outstanding technical requirements.

Within one week, you will receive an e-mail containing information on the amendments required prior to publication. When all required modifications have been addressed, you will receive a formal acceptance letter and your manuscript will proceed to our production department and be scheduled for publication.

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Riccardo Di Giminiani

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: (No Response)

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: (No Response)

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: (No Response)

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: (No Response)

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: (No Response)

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Reviewer #1: No