Review Reports - The Histopathological Examination of the Degeneration of Menisci in Osteoarthritic Knees Using an Adapted Bonar Score: Does Osteoarthritis Equally Influence the Lateral and Medial Menisci?

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Please report that the modified Bonar score was developed by Zabrzyński et al. at the first mention. Then, delete Zabrzyński et al in the other parts of the manuscript and in the captions of the figures.

Has the modified Bonar score been validated for meniscal tissue? If not, how could authors be sure that there is no difference between the lateral and medial menisci? Please clarify this point.

It could be useful to use a validated score for meniscus tissue such as the score of Pauli et al. for comparison. Please discuss about this point.

Please use the term osteoarthritis instead of arthritic that is not specific. Check the whole manuscript.

Introduction

The introduction has to be improved. A brief introduction about osteoarthritis and the role of menisci in early and advanced OA has to be reported.

Inflammation has not been described. This is an important factor as it correlates with symptoms and outcomes (e.g. doi: 10.3390/jcm11154330).

Lines 50-51: please move this part after the description of the menisci. Moreover, the biomechanics role of menisci has to better described.

Lines 72-75: please move this part to the methods section.

Lines 86-95: the microscopically description of the menisci has to be placed before the reporting of Bonar score.

Line 77: Reference 16 is not specific. Please delete.

Line 80: reference 17 is not referred to Park et al. Please correct.

Lines 82-84: reference 19 is not about menisci but long head of biceps tendon. Please substitute with a more specific one.

Materials and methods

Line 114: Please use osteoarthrosis instead of gonarthrosis.

Lines 115-116: Ahlback score has to be described. Please report a specific reference. Ahlbäck grading of knee OA should be not used because of poor reliability. Kellgren Lawrence should be used.

Line 115: osteoarthritis is not “severe unilateral idiopathic arthritis”. Please clarify this important concept.

2.1. Preoperative assessment

Line 124: please report the functional outcomes.

2.3. Histopathological assessment

Please add the complete information (name, city, country, etc.) about all the materials used.

Line 154: reference is lacking. Please add.

2.4. Ethics statement

This part has to be moved at the beginning of the Materials and methods section where the Ethical Committee approval has been provided.

Results

Functional outcomes are not reported. Please add.

Authors should avoid repetitions of data between results reported in the figures/tables.

Table 1: please report how data are presented (number, mean, standard deviation, range).

P-values are lacking. Please report them in the table.

Lesser decimals could be useful.

Lines 349-350: please delete “according to the modified Bonar score by Zabrzyński et al.” It ahs already been reported few lines before that authors are describing the results with the modifeied Bonar score.

Figures

Instead of reporting several figures without statistical differences between the parameters evaluated, it could be useful to summarize these results in specific tables regarding both deformity groups, valgus deformity group and varus deformity group also reporting the p-values. Otherwise, it is better to report directly in the figure to which group authors are referring. Readers cannot understand the figures without reading the captions.

Figures of correlations could be more useful.

Figure 1: Please report only modified Bonar score in the y-axis.

Please delete p-value. It has already been reported that the difference is not significative.

Caption of Figure 1: please report only at the first mention that modified Bonar score was developed by Zabrzyński et al.

Discussion

Lines 385-6: authors reported that this is the first study analyzing microscopic menisci degeneration in patients with osteoarthritis. Pauli et al. had already analyzed human knee menisci in aging and osteoarthritis at macroscopic and microscopic levels in 2011. Please clarify and correct.

Lines 387-388: Other studies investigated meniscus structure by electron microscopy. Please add.

Lines 394-397: authors have to report the first study exploring the use of Bonar score in meniscus pathology. Please add.

Lines 410-411: these lines are a repetiton of the previous concept. Please correct.

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Thank you for your interesting manuscript regarding the feasibility of the Bonar score for the assessment of degenerative menisci. It was interesting to me, but I have some suggestions.

Abstract: short and on-point

Introduction: leads straight to the topic and gives a good overview

Materials and Methods:

Line 129: IFP – please use short-forms after explaining them

The approach and methods are described adequately

Results

Table 1: please use the common term n instead of “no. of patients”

Tables and Figures are fine and commented below comprehensively

Discussion:

Most of the results are discussed and compared with those in the current literature.

I suggest explaining the possible reasons for the similarity of microscopically assessed degenerative changes in the medial and lateral menisci.

Please highlight and mention the future approaches and their clinical applications.

Additional suggestions for Improvements:

Revise sentence structure for clarity and conciseness. Throughout the manuscript, some sentences are too long and therefore misleading.

The absence of information, such as the average BMI and a more detailed breakdown of comorbidities, limits the reader's understanding of the cohort. Furthermore, the predominance of women and varus deformities were not fully accounted for in the manuscript.

Add information about how long the menisci were fixed in formalin before processing, as this can affect tissue quality.

Specify which areas of the menisci were sampled and how many sections were analysed per patient. The methodology for sectioning and sampling the menisci has not yet been described in detail. Without knowing if the samples were taken from comparable regions in each meniscus, the findings could be biased.

The description of light microscopy could be expanded to include magnification levels used for each analysis and whether there was any interobserver variability between the two blinded observers.

Additional details on how the Bonar scoring system was statistically validated in this study. Two experienced observers evaluated the samples, but there was no mention of whether the intra- or inter-observer agreement was assessed quantitatively (for example, Cohen’s kappa). This is critical in histological studies that involve subjective scoring.

Provide more context on why non-parametric tests (Mann–Whitney U test) were chosen and if alternative tests were considered.

The limitations section could be made more robust. For instance, mention how the findings could be affected by the fact that the samples were taken only from patients with end-stage osteoarthritic patients, which may not represent all stages of meniscal degeneration.

Expand the discussion to compare your histological findings more thoroughly with those of previous studies. Highlight similarities and discrepancies in the pathology and scoring systems used.

Include a section discussing the broader implications of this study in clinical practice.

This is a very interesting topic and is well written. After minor changes this manuscript should be suitable for publication.

Sincerely

Comments on the Quality of English Language

minor changes needed

Author Response

Dear Editor,

Thank you for the opportunity to improve and resubmit our manuscript entitled:

“The histopathological examination of menisci degeneration in osteoarthritic knees using adapted Bonar score. Does osteoarthritis equally influence the lateral and medial menisci?”

The suggestions offered by the reviewers have been immensely helpful. We appreciate all the comments on the manuscript.

We have included the reviewer comments, and responded to them individually, indicating how we addressed each concern and describing the changes we have made:

Line 129: IFP – please use short-forms after explaining them

We explained the term.

Table 1: please use the common term n instead of “no. of patients”

We changed the “no. of patients” and used the term n instead.

I suggest explaining the possible reasons for the similarity of microscopically assessed degenerative changes in the medial and lateral menisci.

We added the explanation for the similarity of microscopically assessed degenerative changes in the medial and lateral menisci.

“This could result from the fact that our patients have developed degeneration process with chronic knee conditions - idiopathic arthritis.”

Please highlight and mention the future approaches and their clinical applications.

Future analyzes of the Bonar score in meniscus histopathology should be extended to research on larger population separately on men and women groups. Morevoer, the studies should be introduced in different BMI groups. The future clinical applications could be linked with treatment with unilateral versus total knee arthroplasty.

Revise sentence structure for clarity and conciseness. Throughout the manuscript, some sentences are too long and therefore misleading.

We revised sentence structure throughout the manuscript.

The absence of information, such as the average BMI and a more detailed breakdown of comorbidities, limits the reader's understanding of the cohort. Furthermore, the predominance of women and varus deformities were not fully accounted for in the manuscript.

The studied group was limited however is it often in the histopathological assessment of the tissue. Moreover, in our future studies, which deal with functional outcomes the studied group will be extended.

Add information about how long the menisci were fixed in formalin before processing, as this can affect tissue quality.

For 24 hours in each case.

Specify which areas of the menisci were sampled and how many sections were analysed per patient. The methodology for sectioning and sampling the menisci has not yet been described in detail. Without knowing if the samples were taken from comparable regions in each meniscus, the findings could be biased.

In each specimen, specifically from lateral and medial meniscus, three meniscus areas (posterior root, anterior root, body) were harvested. Finally, the mean score according to three various areas were given to each meniscus.

The description of light microscopy could be expanded to include magnification levels used for each analysis and whether there was any interobserver variability between the two blinded observers.

We added the magnification levels to the manuscript.

There was no bias between two observers. They work together.

Additional details on how the Bonar scoring system was statistically validated in this study. Two experienced observers evaluated the samples, but there was no mention of whether the intra- or inter-observer agreement was assessed quantitatively (for example, Cohen’s kappa). This is critical in histological studies that involve subjective scoring.

There was no bias between two observers. They work together.

Provide more context on why non-parametric tests (Mann–Whitney U test) were chosen and if alternative tests were considered.

All statistical analysis was done in GraphPad program and all the statistical tests were done according to software.

The limitations section could be made more robust. For instance, mention how the findings could be affected by the fact that the samples were taken only from patients with end-stage osteoarthritic patients, which may not represent all stages of meniscal degeneration.

We develop the limitations section as suggested.

“Moreover, the samples were taken only from patients with end-stage of OA, which can influence the results concerning the equal impact of OA on the lateral and medial menisci. Due to the fact that in end-stage of OA there is a high-level of tissue degeneration.”

Expand the discussion to compare your histological findings more thoroughly with those of previous studies. Highlight similarities and discrepancies in the pathology and scoring systems used.

We expanded our discussion.

“In our previous study we also used the Bonar score system in quantifying the pathological changes in meniscal tissue. We quantified the effect of nicotine on meniscal tissue, using Bonar scoring system and its modification in microscopic examination. This was our first attempt to explore the use of the Bonar score in meniscus pathology. Moreover, Park et al. also used the Bonar score in meniscus root pathology. On the other hand, Pauli et al. developed their own grading, histopathological system. They added a main criteria: surface, and also evaluated the cellularity, collagen organization and matrix staining (ground substance), then excluded the tenocytes and vascualrity criteria.”

Include a section discussing the broader implications of this study in clinical practice.
We added this section.

“Future analyzes of the Bonar score in meniscus histopathology should be extended to research on larger population separately on men and women groups. Morevoer, the studies should be introduced in different BMI groups. The future clinical applications could be linked with treatment with unilateral versus total knee arthroplasty.”

We wish to express again our appreciation for the insightful comments which have helped us significantly to improve our manuscript.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

No comments