Comparison of Physical Activity Training Using Augmented Reality and Conventional Therapy on Physical Performance following a Total Knee Replacement: A Randomized Controlled Trial

Round 1

Reviewer 1 Report

Dear authors,

Congratulations on your work. I suggest you provide some ideas for future studies regarding the gender of the sample. In my opinion, the huge difference between males/females was the central gap of your study.

Kind regards

Author Response

Thank you for taking the time to comment on our manuscript. Your comments were highly insightful and enabled us to greatly improve the quality of our manuscript. Please find below our point-by-point responses to your comments.

Reviewer comments:

Dear authors,

Congratulations on your work. I suggest you provide some ideas for future studies regarding the gender of the sample. In my opinion, the huge difference between males/females was the central gap of your study.

Kind regards

Response:

Thank you for taking the time to comment on our manuscript. We totally agree with you regarding the huge gap between males and females. This was also our big challenge during the whole research process. Unfortunately, due to the COVID-19 restrictions in Hospital settings, the ethical committee allowed us to include only volunteers resulting in a limited sample size and an unbalance in gender. We reported this issue in the manuscript as the main limitation. As suggested, ideas for future studies regarding gender has been added in the last part of the “Discussion” section.

Reviewer 2 Report

ABSTRACT

- total knee arthroplasty (TKA); need to be more consistent throughout the paper

-  4 weeks is an inadequate amount of time to determine true strength gains as it takes 6-8 weeks for true cellular changes. Any gains made before that time are purely from motor control and improved recruitment of motor units

-  Real time feedback and motivation for rehab - good ideas; may be better utilized in a home exercise program than in the clinic though 

- “Thought, exercises using AR could be used to provide real-time feedback and motivation for rehabilitation. “ This does not make sense grammatically…

 

INTRODUCTION

- AR is a technology that combines digital information with information from physical-*word*environments and allows users to interact simultaneously with virtual objects in real-time using enhance 3D effects [15]. Spelling error

- In other words, *the* is a need for evidence regarding the effectiveness of AR-based training on the physical performance of patients after orthopedic surgeries. Spelling error

- Our hypothesis is that training with AR would rapidly decrease pain and improve functional ability and its effects would be superior to conventional physical therapy in patients after TKR….. how does AR impact pain? What is the neuroscience behind pain and how does AR tap into that to reduce it?

 

 

MATERIALS & METHODS

- were any of the testers blinded? Double blinded?

- what are the outcome measurements? (Manual muscle test for strength, visual analog scale for pain, goniometer for ROM, and what for balance?)

- one PT for all 3 measures? What was the inter-rater and intra-rater reliability?

- 24 is a relatively small sample size. What were the recruitment measures? Demographics? Chronicity of knee pain? Age? Oswestry scores? Gender? 

- 3 days or more post op? How much more? Inflammatory stage and healing process matters here

- randomization: states participants were blinded, but should probably mention this early on as this is a good thing to declare for strength of results

- The program, including the training and measurements, was under the supervision and guidance of the therapist in charge or trained research assistant - small issue but lots of room for error here, hopefully the trainees were well trained and watched carefully 

- exercises are relatively easy to understand... but if you’re looking for how to say it in the way USA says it: 

(1) Knee extension in a supine position with a high pillow/towel under the knee = quad set

(2) Lifting a sandbag in a supine position with a pillow/towel under the knee = short arc quad (SAQ)

(3) Knee flexion with a band on supine position 

(4) Knee flexion while pulling the heel on supine position = heel slides, usually done with a towel under the heel for assistance

 

Experiment procedure: ART = regimented therapeutic exercises; TBT = 30min PROM + 15min CPM. --> CPM is no longer considered relevant as it’s not been proved to be advantageous to doing nothing. Research has shown that active range of motion (AROM) is superior to passive ROM or nothing at all. What does it say that the superior method delivered via ART is not significantly better than the second-rate method delivered in-person…HOWEVER. If the primary goal was ROM - this may make sense. If the primary goal is long term function - the other method makes sense. 

 

OUTCOME MEASURES: 

1. ROM was the thing being measured - they did a great job assessing and interpreting this. 

2. Muscle strength - good that they had an objective device to measure, but did everyone know how to use it? Did the same person use it per person? Per time measured? **there was nothing mentioned about flexibility of hip flexors, hamstrings, or calves. These are HUGE factors in relation to ROM, strength, and function

3. Pain - VAS, excellent choice as this is the gold standard and commonly used

4. Balance - measured using motion analysis while swaying in different directions. That’s good but.. is it double limb? single limb? Firm surface? Compliant surface? Static? Dynamic? Etc. based on which you choose - why?

 

RESULTS

ROM - Decrease in knee flexion ROM between Pre and post surgery, improvement between post surgery and post PT. Post intervention ART had higher PROM - this is great!

 

DISCUSSION

All the good information in here needed to be at the beginning of the paper because this is what I was looking for. I shouldn’t have to read the whole thing to get there.

* what’s interesting is that someone who is in favor of ART would say that conventional PT is no better than ART but someone who is in PT would say that ART was no better than ART - all a matter of who is writing the paper or interpreting the results. 

 

Burn victims: VR is good for pain, but not so much with the ROM  - this is consistent with the neuroscience behind pain and interpretation of pain. 

 

This explains the positive effect of AR on pain 297 reduction. In the present study, twenty-three of twenty-four participants are women, and 298 it seems that women are more sensitive to pain than men  - evidence???

 

CONCLUSION

No significant difference between the two groups - therefore, AR is not necessary or relevant. 

 

Moreover, realtime feedback in a virtual environment provided to the patients was highly appreciated.* Thus, AR-based training properly motivates participants and gives them more experience 344 during the treatment. This study supports the therapeutic use of AR for total knee arthroplasty rehabilitation and suggests the application of personalized training protocol for 346 better outcomes. 

 

*highly appreciated? Does not matter in science

Author Response

We appreciate the positive and constructive comments on our manuscript. We have considered all the comments carefully and have detailed how we addressed them below. We have also revised our manuscript accordingly. We believe our manuscript is now stronger because of the changes that have been made.

Please see the attachment.

Author Response File: Author Response.docx