Potential Instability and Malfunction of Knee Joints with Vastus Medialis Impairment after Total Knee Arthroplasty

Round 1

Reviewer 1 Report

The paper discuss about potential instability and malfunction after TKA due to VM impairment. The experiment has well designed and conducted. Results presented well and concluded. 

Author Response

Thank you. We really appreciate your kind evaluation for our study.

We got English spell check again with a native English speaking colleague and professional English editing service. 

Reviewer 2 Report

This study investigates potential instability and malfunction of the knee joint with/without VM impairment at normal and post TKA.

In general, the study was well designed, but the manuscript was poorly written. It is highly suggested that the statistical condition and interpretation should be checked with an elite statistician, and the English grammar and readability should be extensively improved before publication.

There are some general and physiological concepts that need to be clarified.

1. The overall experiment seems to only focus on extensors. Is there any consideration of the physiological effects of flexors on the balance and stability of the knee joint? Why? Please explain it.
2. Does this experiment consider screw home rotation of the knee during flexion and extension? Why? Please explain it.

 [Materials and Methods]

1. Line116~120, What is the basis for the angular configuration of the force direction of muscles in each plane? Which literature article configuration is referenced?
2. Line 130, Why use two different p-values, and what do they mean?
3. Figure 2(a), Is the "Fv" in the picture a typo? It should be "Fy."
4. Figure 2(b), the abbreviation of “IMU” should be annotated with the full name.

[Results]

1. Line 158~160, The interpretation of this result description and graphics seems a bit far-fetched.
2. Line 163~169, This comparison is not very appropriate because, basically, the surgical and non-surgical groups come from the different left and right knees, which is different from comparing whether the VM is impaired in a single group (surgical or non-surgical group).

 [Discussion]

1. Line 246~265, There are too many assumptions in this whole paragraph and a lack of experimental scientific evidence. It is recommended that if the motion analysis can be used to understand the changes in the relative spatial coordinates of the femur and tibia in the knee joint.
2. Please add a description of the limitation and make a summary at the end.

Author Response

Please see the attachment.

Author Response File: Author Response.doc

Round 2

Reviewer 2 Report

The author's reply and amendments make this article more complete and readable.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.