Assessment of Quality in Osteoporotic Human Trabecular Bone and Its Relationship to Mechanical Properties

Round 1

Reviewer 1 Report

In this study, Presbitero et al. provided alternative methods to estimate multiple quality parameters of osteoporotic bone, paying particular attention to trabecular bone. Their approach wanted to analyze and combine different assessment, such as porosity, trabecular thickness, and space, and mechanical tests. The purpose of the study is very interesting, and the project was well-conducted. The paper is well-written and makes the reading fluent, the introduction offers exhaustive information to understand the results, the used references are appropriate. However, there are some inaccuracies and doubts to be clarified:

 

• Did the donors receive osteoporosis diagnosis to be eligible as “donors” or they were chosen because of the age? Moreover, why did not the authors choose also older donors to have a wider range of age?

 

• The described machining process is very interesting. Some pictures of the main stages and of the final cubic samples should be added to Figure 1.

 

• Had the authors found some differences in measurements among samples from different zones of the same femoral head? It could be interesting evaluate potential dissimilarities.

 

• Why did not the authors perform porosity measurements in control sample?

 

• In the Discussion section, the authors should discuss their results about trabecular thickness and space comparing them to that already existing in literature.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

This topic is very interesting. Please look at these points: 1. Line 40-41: . "Specifically, this device measures the quantity of mineralization in specified areas of the skeleton". Which areas? femur and lumbar spine? 2. Line 32-33. "The biomechanical competence of trabecular bone is dependent not only on the absolute amount of bone but also on the trabecular microarchitecture [6]." Please discuss this concept further, even small bones have trabecular features useful for biomechanics. Look at this important ref. The Y-shaped trabecular bone structure in the odontoid process of the axis: a CT scan study in 54 healthy subjects and biomechanical considerations. J Neurosurg Spine. 2019 Feb 1:1-8. doi: 10.3171/2018.9.SPINE18396. 3. Lines 47-49:"Relatively small changes in BMD can result in dramatic reductions in the risk of fracture due to the... changes in bone strength [16]." Is this risk the same if the BMD increases or decreases? Please explain better. 4. Lines 57-68: "Although we orient our study to the analysis of trabecular regions, it is important to mention that several publications have extensively analyzed the cortical zones..." Please improve references here, see above, considering also congenital trabecular conditions, see these refs. Regional and experiential differences in surgeon preference for the treatment of cervical facet injuries: a case study survey with the AO Spine Cervical Classification Validation Group. Eur Spine J. 2021 Feb;30(2):517-523. doi: 10.1007/s00586-020-06535-z. -- Congenital absence of a cervical spine pedicle. Neurol India. 2016 Jan-Feb;64(1):189-90. doi: 10.4103/0028-3886.173669. -- Congenital short femur. Saudi Med J. 2012 Apr;33(4):455-6. -- Trabecular bone micro-architecture and bone mineral density in adolescent idiopathic and congenital scoliosis. Orthop Surg. 2009 Feb;1(1):78-83. doi: 10.1111/j.1757-7861.2008.00014.x. PMID: 22009786; PMCID: PMC6640004. 5. Overall the introduction seems to be a bit long, try to reduce it and clearly state what is the aim of this paper. Lines 90-94 can be removed in my opinion. 6. Lines 279-282: "Therefore, we firmly believe an approximation of... comparison between quality and quantity parameters of our samples." What this sentence mean? Please revise. 7. Line 317-319: "Therefore, our results provide the true BMD of trabecular tissue, and this is an important assessment as this tissue is the most affected part of bone by osteoporosis." This is a good result, highlight it in conclusion section. 8. Lines 223-226: "Based on that, the error between the gold-references and such best approxi224 mation was always between 0.42% and ... concrete glass, and alkaline activated composite, 226 the bias was 1.66%, 14.63%, and 24.77%, respectively". are these values important in clinical field? If yes, please improve this point. 9. Figure 9 is very interesting. Can authors add more detail in the figure legend? Overall a good paper, but a revision is required.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Authors solved all my criticisms.