Change in Physical and Mental Quality-of-Life between the Short- and Mid-Term Periods after Cervical Laminoplasty for Cervical Spondylotic Myelopathy: A Retrospective Cohort Study with Minimum 5 Years Follow-up

Round 1

Reviewer 1 Report

Tamai et al have done a retrospective investigation of 80 patients with cervical myelopathy regarding to physical assessment and mental quality of life. 

In my opinion the first thing is the missed surgical procedure in the title. Alle patients have received a laminoplasty. The performance is not written in detail.

In second, MRI findings were not correlated. Especially in myelopathy, this is an important issue to analyse the significance of performed therapy. The might be a big difference between varying extent of myelopathy signs. 

At the end, a a reader it doesn't give us a help for decision. In which situation, should be perform a therapy) How would the alternative treatment?

A novelty is not seen in this paper.  

Author Response

Response to Reviewer 1:

Tamai et al have done a retrospective investigation of 80 patients with cervical myelopathy regarding to physical assessment and mental quality of life. In my opinion the first thing is the missed surgical procedure in the title. All patients have received a laminoplasty. The performance is not written in detail.

Response: We deeply appreciate the reviewer’s careful review and insightful comments. We completely agree with reviewer’s suggestion of adding “laminoplasty” to our title. Accordingly, we have revised the title in our revised manuscript. Additionally, we have revised subsection “2.3. Surgical procedure” to improve the clarity of our surgical procedures. Thanks for your important suggestion.  (Line 68-75)

In second, MRI findings were not correlated. Especially in myelopathy, this is an important issue to analyses the significance of performed therapy. The might be a big difference between varying extent of myelopathy signs.

Response: These are very important points. We carefully reviewed preoperative MRI findings to evaluate the numbers of stenosis levels and snake-eye appearance. We have defined MRI findings in the “Material and Methods” section and summarized the results in Table 1. (Line 76-82, Table1, and Line 149-151). However, as the radiological findings did not correlate with the PCS/MCS score changes, we did not include the variable in our final multivariate analysis. We appreciate your suggestion.

At the end, a reader it doesn't give us a help for decision. In which situation, should be perform a therapy). How would the alternative treatment? A novelty is not seen in this paper.

Response: We agree with your comment. We also realized that we need to revise our manuscript to highlight the novelty of the study. Hence, in the revised manuscript, we added that “physicians may have to continue to follow-up on patients with a cJOA score of <13.0 for more than 2 years. Furthermore, physicians could consider additional therapy, such as rehabilitation and/or exercises, especially for patients with a cJOA score of <13.0 during the short-term follow-up period” in the Discussion section. (Line 236-240)

Reviewer 2 Report

I read your study with interest, there are indeed not many studies with longer than 2 year follow up, therefore this provides a significant piece of knowledge to clinician for patient counseling. I do have a couple of minor comments:

1) please change the terminology to Degenerative Cervical Myelopathy from CSM. This terminology has been adopted by guidelines and multistakholder surveys. Reference 6 of your paper introduced this term in 2015.

2) Are you able to provide information about reoperation rates or complications rates and if this related to these health quality outcomes?

3) I would discuss in greater detail in your discussion some of the other findings in the literature regarding health quality outcomes at 2 years, a few papers have been published regarding this.

Author Response

Response to Reviewer 2:

I read your study with interest, there are indeed not many studies with longer than 2 year follow up, therefore this provides a significant piece of knowledge to clinician for patient counseling. Response: We would like to thank the reviewer for their careful review of our manuscript and kind feedback.

Please change the terminology to Degenerative Cervical Myelopathy from CSM. This terminology has been adopted by guidelines and multistakholder surveys. Reference 6 of your paper introduced this term in 2015.

Response: We completely agree with this comment; DCM is the “world standard terminology,” which includes cervical spondylotic myelopathy (CSM), ossification of the posterior longitudinal ligament (OPLL), ossification of the ligamentum flavum (OLF), and other minor degenerative conditions causing cervical myelopathy. However, in the current study, we excluded patients with OPLL because we thought that there would be major differences in long-term QOL changes between patients with CSM and OPLL. (Line 66) Hence, we concluded that CSM will be more appropriate than DCM in our study. I hope our reasoning is acceptable.

Are you able to provide information about reoperation rates or complications rates and if this related to these health quality outcomes?

Response: We sincerely appreciate you for bringing up this issue. In the revised manuscript, we have indicated the number of complications, including C5 palsy and surgical site infection, and reoperation rate in Table 1. However, we did not include them in the multivariate analysis because the total numbers were too low to provide reliable statistical results. We realized this would be a critical limitation of this study. Hence, we have added a statement regarding this limitation in the limitation section. (Line84-87, Table1, Line246-247)

I would discuss in greater detail in your discussion some of the other findings in the literature regarding health quality outcomes at 2 years, a few papers have been published regarding this.

Response: Thank you for your valuable advise. We have added detailed discussion about QOL improvement at 2 years postoperatively in comparison with the results of previous studies (Line 204-212).

Round 2

Reviewer 1 Report

Authors have indeed answered the questions properly and have done an adequate calculation, especially regarding MRI findings. The novelty is not high. But the revised manuscript shows in my opinion a more clearly scientific approach with an uncomplicated answer.