Could Subtle Obstetrical Brachial Plexus Palsy Be Related to Unilateral B Glenoid Osteoarthritis?
, Hugo Bothorel 4, Philippe Collin 5, Bassem Elhassan 6, Luc Favard 7, Nazira Bernal 8, Patric Raiss 9 and George S. Athwal 10
Lars Henrik Frich
Round 1
Reviewer 1 Report
This manuscript has been revised. I have 3 minor comments:
The manuscript is based on the PRISMA guidelines which should be mentioned in the abstract
Figures does not belong in "discussions" and figure 3 should be placed in the "results" section.
Table 2 is rather extensive, and I believe it should be moved to "supplementary materials"
Author Response
|
Reviewer 1 |
|
|
| Comments |
Answers/Corrections |
Line |
|
Suggestions for Authors |
||
| This manuscript has been revised. I have 3 minor comments: 1- The manuscript is based on the PRISMA guidelines which should be mentioned in the abstract 2- Figures does not belong in "discussions" and figure 3 should be placed in the "results" section. 3- Table 2 is rather extensive, and I believe it should be moved to "supplementary materials". |
1- Added: “A literature review was performed following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) to estimate the incidence of OBPP risk factors in the general population.”
2- Figures no longer belong in discussions. The Figure 3 was moved to the results section.
3- We completely agree. The Table 2 was moved to supplementary materials since important literature results are already summarized in the Table 1.
|
1- Lines 26-8
2- Lines 138-45
3- Supplementary Materials
|
Reviewer 2 Report
The authors thoroughly addressed the suggestions provided in the previous review, improving the quality of their report. Yet, there are some small points that need improvement.
I think it would be advisable to better define the study population: were they patients presenting to the orthopaedic surgeon for shoulder problems and were prescribed a CT scan? Or were they selected among the CT scans performed at the institution?
In the methods section, it is stated that unilateral or bilateral CT scans were performed, but in the results section a percentage of bilateral disease is provided. Could you, please, clarify how the diagnosis was made?
In line 134, referral to the use of R has been made, but the kind of computations made with the program is not explained. Could you, please, enhance this section?
Author Response
|
Reviewer 2 |
|
|
| Comments |
Answers/Corrections |
Line |
|
Suggestions for Authors |
||
| The authors thoroughly addressed the suggestions provided in the previous review, improving the quality of their report. Yet, there are some small points that need improvement. 1- I think it would be advisable to better define the study population: were they patients presenting to the orthopaedic surgeon for shoulder problems and were prescribed a CT scan? Or were they selected among the CT scans performed at the institution? 2- In the methods section, it is stated that unilateral or bilateral CT scans were performed, but in the results section a percentage of bilateral disease is provided. Could you, please, clarify how the diagnosis was made? 3- In line 134, referral to the use of R has been made, but the kind of computations made with the program is not explained. Could you, please, enhance this section? |
Thank you for your comments. Please see our answers below.
1- Specified: “All patients presented to the orthopaedic surgeon for shoulder problems and were prescribed a CT scan.”
2- Specified: “A bilateral CT scan was systematically performed if the patient symptomatology was suggestive of a shoulder pathology on both sides.”
3- Explained: “to summarize the literature findings, describe the characteristics of the present patient series (descriptive statistics) and create the forest plot illustration.” |
1-Lines 84-5
2- Lines 88-9
3- Lines 126-9 |
Author Response File: 
Author Response.pdf
Reviewer 3 Report
Overview:
The authors have designed a retrospective evaluation of 187 shoulders with static posterior subluxation of the humeral head but without clear signs of OBPP lesions.
Strengths
- Overall, this study addresses an important and interesting subject
- Relatively large cohort for this specific problem (type B glenoid)
- Good comparison to the literature
Although no definitive correlation was found between OBPP and Walch type B OA the hypothesis make a lot of sense and as concluded other studies are needed to further investigate the possible association between subclinical neurological lesions during child
Weaknesses
As stated in the limitations paragraph
ALarger cohort is needed for this type of study
Table 2
Is too long and should be presented in some other fashion
Author Response
|
Reviewer 3 |
|
|
| Comments |
Answers/Corrections |
Line |
| Comments and Suggestions for Authors |
|
|
| Overview: The authors have designed a retrospective evaluation of 187 shoulders with static posterior subluxation of the humeral head but without clear signs of OBPP lesions. |
/ |
|
| Strengths· Overall, this study addresses an important and interesting subject· Relatively large cohort for this specific problem (type B glenoid)· Good comparison to the literature Although no definitive correlation was found between OBPP and Walch type B OA the hypothesis make a lot of sense and as concluded other studies are needed to further investigate the possible association between subclinical neurological lesions during child |
Thank you |
|
| Weaknesses As stated in the limitations paragraph a larger cohort is needed for this type of study |
We agree. Limitation acknowledged. |
|
| Table 2Is too long and should be presented in some other fashion |
As suggested by the reviewer 1, the Table 2 was moved to supplementary materials since important literature results are already summarized in the Table 1.
|
Supplementary materials |
Author Response File: Author Response.pdf
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.
Round 1
Reviewer 1 Report
This body of this work aims to determine the incidence of OBPP risk factors in patients with glenoid type B osteoarthritis. The assessment and treatment of the glenoid morphologic changes is challenging and requires attention.
The manuscript has an interesting hypothesis but provides little new information on the issue of glenoid dysplasia in osteoarthritic patients.
taken into consideration the methodological restraints.
Introduction:
The Incidence of OBPL is a little higher than reported: 1-5/1000 births Ref : Paediatr Child Health. 2006 Feb;11(2):93-100. Perinatal brachial plexus palsy. Andersen J1, Watt J, Olson J, Van Aerde J.
Line 43: The etiology of OBPP is presumed to be traumatic traction of the brachial plexus nerve roots during childbirth. Neurogenic injury results in muscle and joint imbalance that leads to morphologic changes that progress with age.
It is unclear what the authors here refer to. Waters and Bae (JBJS 2008) suggested that glenohumeral deformity may appear early in life, progress with age and correlates with internal rotation contracture. Glenoid dysplasia in OBPL usually is present as early as a few months after debut but the association between age and morphologic changes is not fully understood.
Line 45: Commonly, an internal rotation contracture occurs due to muscle imbalance between the subscapularis and posterior cuff with resultant posterior subluxation and retroversion of the glenohumeral joint.
The authors should give an explanation about how excessive retroversion is caused by muscle imbalance. Importance of glenoid ossification centers could strengthen this argument.
Methods:
The presentation of data characterises a review or meta-analyses and does not follow traditional guidelines.
A minor concern that I have is the interview part, which is qualitative at best.
Results:
Validity of data could be questioned. Not many patients 60+ years of age remembers if the sustained a clavicular fracture during delivery. Etc.
Results:
R data missing
Discussion:
Is short and precise.
Figures are missing.
The reader can profit from a figure showing glenoid dysplasia in both cases
Author Response
Response to Reviewers
Date: Feb 1st, 2021
|
Reviewer 1 |
|
|
| Comments |
Answers/Corrections |
Line |
|
Introduction |
||
| This body of this work aims to determine the incidence of OBPP risk factors in patients with glenoid type B osteoarthritis. The assessment and treatment of the glenoid morphologic changes is challenging and requires attention. The manuscript has an interesting hypothesis but provides little new information on the issue of glenoid dysplasia in osteoarthritic patients. taken into consideration the methodological restraints.
-> The Incidence of OBPL is a little higher than reported: 1-5/1000 births Ref : Paediatr Child Health. 2006 Feb;11(2):93-100. Perinatal brachial plexus palsy. Andersen J1, Watt J, Olson J, Van Aerde J. |
Modified |
Line 66
|
| Line 43: The etiology of OBPP is presumed to be traumatic traction of the brachial plexus nerve roots during childbirth. Neurogenic injury results in muscle and joint imbalance that leads to morphologic changes that progress with age. It is unclear what the authors here refer to. Waters and Bae (JBJS 2008) suggested that glenohumeral deformity may appear early in life, progress with age and correlates with internal rotation contracture. Glenoid dysplasia in OBPL usually is present as early as a few months after debut but the association between age and morphologic changes is not fully understood. |
We agree with this comment. Severe (clinically obvious lesions) OBPP might be present early as a few months after debut. It may take a longer time in case of subtle lesion.
We change the manuscript as follows: The etiology of OBPP is presumed to be traumatic traction of the brachial plexus nerve roots during childbirth. Neurogenic injury results in muscle and joint imbalance that leads to morphologic changes that progress with time, depending of the severity of the lesion. |
Line 71 |
| Line 45: Commonly, an internal rotation contracture occurs due to muscle imbalance between the subscapularis and posterior cuff with resultant posterior subluxation and retroversion of the glenohumeral joint. The authors should give an explanation about how excessive retroversion is caused by muscle imbalance. Importance of glenoid ossification centers could strengthen this argument. |
The ratio of the infraspinatus and teres minor volume to the subscapularis volume is associated with glenoid morphology, retroversion, and humeral-head subluxation. This suggests that an axial plane force imbalance is associated with glenoid deformity. (doi :10.2106/JBJS.19.00086) However, the importance of ossification center is not yet clearly defined.
We change for: It has been shown that muscle imbalance between the subscapularis and posterior cuff is associated to posterior subluxation and retroversion of the glenohumeral joint. (doi : 10.2106/JBJS.19.00086)
|
Lines 71-2 |
|
Methods |
||
| The presentation of data characterises a review or meta-analyses and does not follow traditional guidelines. A minor concern that I have is the interview part, which is qualitative at best. |
The authors re-performed a thorough literature review according to the PRISMA method.
|
Lines 124-144 |
|
Results |
||
| Validity of data could be questioned. Not many patients 60+ years of age remembers if the sustained a clavicular fracture during delivery. Etc. |
We agree with this comment. However, we believe that the collected data are representative for the following reasons. First, the birth book is generally kept by patients and we systematically asked for. Second, we asked routinely patients to questions their parents about delivery conditions. Third, a clavicular fracture during delivery makes parents feeling guilty, leading to psychologically and emotionally damage. Such experience is usually shared with descendants.
We added this information in the limitations of the study |
Lines 248-251. |
| R data missing |
We have to admit that we did not fully understand the question. We are sorry for this and will enjoy answering it if formulated differently. If it refers to the version of R, the information is already available. |
Line 153 |
|
Discussion |
||
|
Is short and precise. Figures are missing. The reader can profit from a figure showing glenoid dysplasia in both cases |
Thank you. The authors added one figure. The legend of the figure is the following: Illustration of C (A) and B (B) glenoids. C glenoid observed in severe neurological lesion are characterized by a retroversion above 25 degrees, a humeral head subluxation above 80%, a rounded posterior rim, a “lazy J” sign and a hypoplastic neck. On the other hand, B glenoid are characterized by a retroversion above 15 degrees, a humeral head subluxation above 60%, a concave glenoid, osteophytes, a sharp posterior rim and a normal glenoid neck.
|
Figure 3 lines 224-231. |
|
Reviewer 2 |
|
|
| Comments |
Answers/Corrections |
Line |
| The paper explores the relation between subclinical obstetric brachial plexus palsy and developement of type B glenoid osteoarthritis. The underlying hypotesis is that a subclinical neurological damage to the shoulder could cause a muscular imbalance leading to posterior migration of the humeral head and degenerative changes. Unfortunately, risk factors for obstetric brachial plexus palsy and, therefore, for subclinical neurological damage, were not found in higher prevalence in a cohort of patients with a type B glenoid.The paper is generally well written, yet there are a few points that I think need to be clarified. |
Thank you for your comments. Please see our answers below. |
|
|
Introduction |
||
| The introduction is appropriate, but the aim of the study is expressed only as a hypotesis. I feel that the aim of the study should be plainly stated. |
We added a third paragraph in the introduction |
Lines 93-102 |
|
Material and methods |
||
| In the Patients and Methods section, I suggest improving the description of patients' recruitment and inclusion criteria: no information about the involved centres is provided, the reason why patients presented to the institutions is not provided and the reason for the prescription of the CT scan is not stated. Furthermore, no information is given about the CT scanning protocol: did every patient undergo a bilateral shoulder CT scan? |
We added this information. |
Lines 105-112. |
| Osteoarthritis with a type B glenoid is uncommon in young patients, that are, anyway, included in the study cohort. An explanation for this should be provided. |
Thank you for this interesting remark. Patients with posterior static subluxation are usually young and present after a while B glenoid. This category of patient was included as well. This has been specified if the manuscript. |
Line 108-112.
|
| It is stated that data regarding the involved side are collected, but they seem not to be reported in the results section nor elsewhere. |
deleted |
Line 118
|
| Accurate results of the literature review are provided in the Results section. Since the data obtained from this review are an essential part of this paper, details on the methods of the literature review should be provided in the methods section. |
We re-performed the literature review according to the PRISMA guidelines |
Lines 124-144 Figure 1 |
|
Results |
||
| The Results section is clear and concise and the tables are well built. |
Thank you |
|
|
Discussion |
||
| Results are extensively discussed in the light of available literature. Limitations of the study are just listed in the text; a deeper analysis would help direction future investigations. |
Limitations have been added or better explained. Please refer to the above questions. |
Lines 245-51 |
| Some minor spelling errors can be found throughout the text. |
Some spelling errors have been corrected (i.e clavicular line 120). |
Line 120 Tables 1 and 2 |
|
Reviewer 3 |
|
|
| Comments |
Answers/Corrections |
Line |
| The article attempts to explore the cause of static posterior subluxation and B2 Glenoids. They have done a reasonable job of exploring BBPP as a contribution. While it does not prove that Hypothesis it is of clinical value in that it calls attention again to the idea that muscular imbalance likely causes the subluxation and wear pattern even if the cause of the imbalance is not yet understood. The article includes a good bibliography to have available in the literature for future studies to access. Of course it would have been preferable to have prospective or actual reports of details of the birthing rather than just anecdotal from the patients and their parents |
Thank you |
|
Author Response File: 
Author Response.docx
Reviewer 2 Report
The paper explores the relation between subclinical obstetric brachial plexus palsy and developement of type B glenoid osteoarthritis. The underlying hypotesis is that a subclinical neurological damage to the shoulder could cause a muscular imbalance leading to posterior migration of the humeral head and degenerative changes. Unfortunately, risk factors for obstetric brachial plexus palsy and, therefore, for subclinical neurological damage, were not found in higher prevalence in a cohort of patients with a type B glenoid.
The paper is generally well written, yet there are a few points that I think need to be clarified.
The introduction is appropriate, but the aim of the study is expressed only as a hypotesis. I feel that the aim of the study should be plainly stated.
In the Patients and Methods section, I suggest improving the description of patients' recruitment and inclusion criteria: no information about the involved centres is provided, the reason why patients presented to the institutions is not provided and the reason for the prescription of the CT scan is not stated. Furthermore, no information is given about the CT scanning protocol: did every patient undergo a bilateral shoulder CT scan?
Osteoarthritis with a type B glenoid is uncommon in young patients, that are, anyway, included in the study cohort. An explanation for this should be provided.
It is stated that data regarding the involved side are collected, but they seem not to be reported in the results section nor elsewhere.
Accurate results of the literature review are provided in the Results section. Since the data obtained from this review are an essential part of this paper, details on the methods of the literature review should be provided in the methods section.
The Results section is clear and concise and the tables are well built.
Results are extensively discussed in the light of available literature. Limitations of the study are just listed in the text; a deeper analysis would help direction future investigations.
Some minor spelling errors can be found throughout the text.
Author Response
Response to Reviewers
Date: Feb 1st, 2021
|
Reviewer 1 |
|
|
| Comments |
Answers/Corrections |
Line |
|
Introduction |
||
| This body of this work aims to determine the incidence of OBPP risk factors in patients with glenoid type B osteoarthritis. The assessment and treatment of the glenoid morphologic changes is challenging and requires attention. The manuscript has an interesting hypothesis but provides little new information on the issue of glenoid dysplasia in osteoarthritic patients. taken into consideration the methodological restraints.
-> The Incidence of OBPL is a little higher than reported: 1-5/1000 births Ref : Paediatr Child Health. 2006 Feb;11(2):93-100. Perinatal brachial plexus palsy. Andersen J1, Watt J, Olson J, Van Aerde J. |
Modified |
Line 66
|
| Line 43: The etiology of OBPP is presumed to be traumatic traction of the brachial plexus nerve roots during childbirth. Neurogenic injury results in muscle and joint imbalance that leads to morphologic changes that progress with age. It is unclear what the authors here refer to. Waters and Bae (JBJS 2008) suggested that glenohumeral deformity may appear early in life, progress with age and correlates with internal rotation contracture. Glenoid dysplasia in OBPL usually is present as early as a few months after debut but the association between age and morphologic changes is not fully understood. |
We agree with this comment. Severe (clinically obvious lesions) OBPP might be present early as a few months after debut. It may take a longer time in case of subtle lesion.
We change the manuscript as follows: The etiology of OBPP is presumed to be traumatic traction of the brachial plexus nerve roots during childbirth. Neurogenic injury results in muscle and joint imbalance that leads to morphologic changes that progress with time, depending of the severity of the lesion. |
Line 71 |
| Line 45: Commonly, an internal rotation contracture occurs due to muscle imbalance between the subscapularis and posterior cuff with resultant posterior subluxation and retroversion of the glenohumeral joint. The authors should give an explanation about how excessive retroversion is caused by muscle imbalance. Importance of glenoid ossification centers could strengthen this argument. |
The ratio of the infraspinatus and teres minor volume to the subscapularis volume is associated with glenoid morphology, retroversion, and humeral-head subluxation. This suggests that an axial plane force imbalance is associated with glenoid deformity. (doi :10.2106/JBJS.19.00086) However, the importance of ossification center is not yet clearly defined.
We change for: It has been shown that muscle imbalance between the subscapularis and posterior cuff is associated to posterior subluxation and retroversion of the glenohumeral joint. (doi : 10.2106/JBJS.19.00086)
|
Lines 71-2 |
|
Methods |
||
| The presentation of data characterises a review or meta-analyses and does not follow traditional guidelines. A minor concern that I have is the interview part, which is qualitative at best. |
The authors re-performed a thorough literature review according to the PRISMA method.
|
Lines 124-144 |
|
Results |
||
| Validity of data could be questioned. Not many patients 60+ years of age remembers if the sustained a clavicular fracture during delivery. Etc. |
We agree with this comment. However, we believe that the collected data are representative for the following reasons. First, the birth book is generally kept by patients and we systematically asked for. Second, we asked routinely patients to questions their parents about delivery conditions. Third, a clavicular fracture during delivery makes parents feeling guilty, leading to psychologically and emotionally damage. Such experience is usually shared with descendants.
We added this information in the limitations of the study |
Lines 248-251. |
| R data missing |
We have to admit that we did not fully understand the question. We are sorry for this and will enjoy answering it if formulated differently. If it refers to the version of R, the information is already available. |
Line 153 |
|
Discussion |
||
|
Is short and precise. Figures are missing. The reader can profit from a figure showing glenoid dysplasia in both cases |
Thank you. The authors added one figure. The legend of the figure is the following: Illustration of C (A) and B (B) glenoids. C glenoid observed in severe neurological lesion are characterized by a retroversion above 25 degrees, a humeral head subluxation above 80%, a rounded posterior rim, a “lazy J” sign and a hypoplastic neck. On the other hand, B glenoid are characterized by a retroversion above 15 degrees, a humeral head subluxation above 60%, a concave glenoid, osteophytes, a sharp posterior rim and a normal glenoid neck.
|
Figure 3 lines 224-231. |
|
Reviewer 2 |
|
|
| Comments |
Answers/Corrections |
Line |
| The paper explores the relation between subclinical obstetric brachial plexus palsy and developement of type B glenoid osteoarthritis. The underlying hypotesis is that a subclinical neurological damage to the shoulder could cause a muscular imbalance leading to posterior migration of the humeral head and degenerative changes. Unfortunately, risk factors for obstetric brachial plexus palsy and, therefore, for subclinical neurological damage, were not found in higher prevalence in a cohort of patients with a type B glenoid.The paper is generally well written, yet there are a few points that I think need to be clarified. |
Thank you for your comments. Please see our answers below. |
|
|
Introduction |
||
| The introduction is appropriate, but the aim of the study is expressed only as a hypotesis. I feel that the aim of the study should be plainly stated. |
We added a third paragraph in the introduction |
Lines 93-102 |
|
Material and methods |
||
| In the Patients and Methods section, I suggest improving the description of patients' recruitment and inclusion criteria: no information about the involved centres is provided, the reason why patients presented to the institutions is not provided and the reason for the prescription of the CT scan is not stated. Furthermore, no information is given about the CT scanning protocol: did every patient undergo a bilateral shoulder CT scan? |
We added this information. |
Lines 105-112. |
| Osteoarthritis with a type B glenoid is uncommon in young patients, that are, anyway, included in the study cohort. An explanation for this should be provided. |
Thank you for this interesting remark. Patients with posterior static subluxation are usually young and present after a while B glenoid. This category of patient was included as well. This has been specified if the manuscript. |
Line 108-112.
|
| It is stated that data regarding the involved side are collected, but they seem not to be reported in the results section nor elsewhere. |
deleted |
Line 118
|
| Accurate results of the literature review are provided in the Results section. Since the data obtained from this review are an essential part of this paper, details on the methods of the literature review should be provided in the methods section. |
We re-performed the literature review according to the PRISMA guidelines |
Lines 124-144 Figure 1 |
|
Results |
||
| The Results section is clear and concise and the tables are well built. |
Thank you |
|
|
Discussion |
||
| Results are extensively discussed in the light of available literature. Limitations of the study are just listed in the text; a deeper analysis would help direction future investigations. |
Limitations have been added or better explained. Please refer to the above questions. |
Lines 245-51 |
| Some minor spelling errors can be found throughout the text. |
Some spelling errors have been corrected (i.e clavicular line 120). |
Line 120 Tables 1 and 2 |
|
Reviewer 3 |
|
|
| Comments |
Answers/Corrections |
Line |
| The article attempts to explore the cause of static posterior subluxation and B2 Glenoids. They have done a reasonable job of exploring BBPP as a contribution. While it does not prove that Hypothesis it is of clinical value in that it calls attention again to the idea that muscular imbalance likely causes the subluxation and wear pattern even if the cause of the imbalance is not yet understood. The article includes a good bibliography to have available in the literature for future studies to access. Of course it would have been preferable to have prospective or actual reports of details of the birthing rather than just anecdotal from the patients and their parents |
Thank you |
|
Author Response File: Author Response.docx
Reviewer 3 Report
The article attempts to explore the cause of static posterior subluxation and B2 Glenoids. They have done a reasonable job of exploring BBPP as a contribution.
While it does not prove that Hypothesis it is of clinical value in that it calls attention again to the idea that muscular imbalance likely causes the subluxation and wear pattern even if the cause of the imbalance is not yet understood.
The article includes a good bibliography to have available in the literature for future studies to access.
Of course it would have been preferable to have prospective or actual reports of details of the birthing rather than just anecdotal from the patients and their parents
Author Response
Response to Reviewers
Date: Feb 1st, 2021
|
Reviewer 1 |
|
|
| Comments |
Answers/Corrections |
Line |
|
Introduction |
||
| This body of this work aims to determine the incidence of OBPP risk factors in patients with glenoid type B osteoarthritis. The assessment and treatment of the glenoid morphologic changes is challenging and requires attention. The manuscript has an interesting hypothesis but provides little new information on the issue of glenoid dysplasia in osteoarthritic patients. taken into consideration the methodological restraints.
-> The Incidence of OBPL is a little higher than reported: 1-5/1000 births Ref : Paediatr Child Health. 2006 Feb;11(2):93-100. Perinatal brachial plexus palsy. Andersen J1, Watt J, Olson J, Van Aerde J. |
Modified |
Line 66
|
| Line 43: The etiology of OBPP is presumed to be traumatic traction of the brachial plexus nerve roots during childbirth. Neurogenic injury results in muscle and joint imbalance that leads to morphologic changes that progress with age. It is unclear what the authors here refer to. Waters and Bae (JBJS 2008) suggested that glenohumeral deformity may appear early in life, progress with age and correlates with internal rotation contracture. Glenoid dysplasia in OBPL usually is present as early as a few months after debut but the association between age and morphologic changes is not fully understood. |
We agree with this comment. Severe (clinically obvious lesions) OBPP might be present early as a few months after debut. It may take a longer time in case of subtle lesion.
We change the manuscript as follows: The etiology of OBPP is presumed to be traumatic traction of the brachial plexus nerve roots during childbirth. Neurogenic injury results in muscle and joint imbalance that leads to morphologic changes that progress with time, depending of the severity of the lesion. |
Line 71 |
| Line 45: Commonly, an internal rotation contracture occurs due to muscle imbalance between the subscapularis and posterior cuff with resultant posterior subluxation and retroversion of the glenohumeral joint. The authors should give an explanation about how excessive retroversion is caused by muscle imbalance. Importance of glenoid ossification centers could strengthen this argument. |
The ratio of the infraspinatus and teres minor volume to the subscapularis volume is associated with glenoid morphology, retroversion, and humeral-head subluxation. This suggests that an axial plane force imbalance is associated with glenoid deformity. (doi :10.2106/JBJS.19.00086) However, the importance of ossification center is not yet clearly defined.
We change for: It has been shown that muscle imbalance between the subscapularis and posterior cuff is associated to posterior subluxation and retroversion of the glenohumeral joint. (doi : 10.2106/JBJS.19.00086)
|
Lines 71-2 |
|
Methods |
||
| The presentation of data characterises a review or meta-analyses and does not follow traditional guidelines. A minor concern that I have is the interview part, which is qualitative at best. |
The authors re-performed a thorough literature review according to the PRISMA method.
|
Lines 124-144 |
|
Results |
||
| Validity of data could be questioned. Not many patients 60+ years of age remembers if the sustained a clavicular fracture during delivery. Etc. |
We agree with this comment. However, we believe that the collected data are representative for the following reasons. First, the birth book is generally kept by patients and we systematically asked for. Second, we asked routinely patients to questions their parents about delivery conditions. Third, a clavicular fracture during delivery makes parents feeling guilty, leading to psychologically and emotionally damage. Such experience is usually shared with descendants.
We added this information in the limitations of the study |
Lines 248-251. |
| R data missing |
We have to admit that we did not fully understand the question. We are sorry for this and will enjoy answering it if formulated differently. If it refers to the version of R, the information is already available. |
Line 153 |
|
Discussion |
||
|
Is short and precise. Figures are missing. The reader can profit from a figure showing glenoid dysplasia in both cases |
Thank you. The authors added one figure. The legend of the figure is the following: Illustration of C (A) and B (B) glenoids. C glenoid observed in severe neurological lesion are characterized by a retroversion above 25 degrees, a humeral head subluxation above 80%, a rounded posterior rim, a “lazy J” sign and a hypoplastic neck. On the other hand, B glenoid are characterized by a retroversion above 15 degrees, a humeral head subluxation above 60%, a concave glenoid, osteophytes, a sharp posterior rim and a normal glenoid neck.
|
Figure 3 lines 224-231. |
|
Reviewer 2 |
|
|
| Comments |
Answers/Corrections |
Line |
| The paper explores the relation between subclinical obstetric brachial plexus palsy and developement of type B glenoid osteoarthritis. The underlying hypotesis is that a subclinical neurological damage to the shoulder could cause a muscular imbalance leading to posterior migration of the humeral head and degenerative changes. Unfortunately, risk factors for obstetric brachial plexus palsy and, therefore, for subclinical neurological damage, were not found in higher prevalence in a cohort of patients with a type B glenoid.The paper is generally well written, yet there are a few points that I think need to be clarified. |
Thank you for your comments. Please see our answers below. |
|
|
Introduction |
||
| The introduction is appropriate, but the aim of the study is expressed only as a hypotesis. I feel that the aim of the study should be plainly stated. |
We added a third paragraph in the introduction |
Lines 93-102 |
|
Material and methods |
||
| In the Patients and Methods section, I suggest improving the description of patients' recruitment and inclusion criteria: no information about the involved centres is provided, the reason why patients presented to the institutions is not provided and the reason for the prescription of the CT scan is not stated. Furthermore, no information is given about the CT scanning protocol: did every patient undergo a bilateral shoulder CT scan? |
We added this information. |
Lines 105-112. |
| Osteoarthritis with a type B glenoid is uncommon in young patients, that are, anyway, included in the study cohort. An explanation for this should be provided. |
Thank you for this interesting remark. Patients with posterior static subluxation are usually young and present after a while B glenoid. This category of patient was included as well. This has been specified if the manuscript. |
Line 108-112.
|
| It is stated that data regarding the involved side are collected, but they seem not to be reported in the results section nor elsewhere. |
deleted |
Line 118
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| Accurate results of the literature review are provided in the Results section. Since the data obtained from this review are an essential part of this paper, details on the methods of the literature review should be provided in the methods section. |
We re-performed the literature review according to the PRISMA guidelines |
Lines 124-144 Figure 1 |
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Results |
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| The Results section is clear and concise and the tables are well built. |
Thank you |
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Discussion |
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| Results are extensively discussed in the light of available literature. Limitations of the study are just listed in the text; a deeper analysis would help direction future investigations. |
Limitations have been added or better explained. Please refer to the above questions. |
Lines 245-51 |
| Some minor spelling errors can be found throughout the text. |
Some spelling errors have been corrected (i.e clavicular line 120). |
Line 120 Tables 1 and 2 |
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Reviewer 3 |
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| Comments |
Answers/Corrections |
Line |
| The article attempts to explore the cause of static posterior subluxation and B2 Glenoids. They have done a reasonable job of exploring BBPP as a contribution. While it does not prove that Hypothesis it is of clinical value in that it calls attention again to the idea that muscular imbalance likely causes the subluxation and wear pattern even if the cause of the imbalance is not yet understood. The article includes a good bibliography to have available in the literature for future studies to access. Of course it would have been preferable to have prospective or actual reports of details of the birthing rather than just anecdotal from the patients and their parents |
Thank you |
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Author Response File: Author Response.docx
