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. 2024 May 15;19(5):e0295350. doi: 10.1371/journal.pone.0295350

Evaluation of the horizontal approach to the medial malleolar facet in sagittal talar fractures through dorsiflexion and plantarflexion positions

Xian Li 1,2,3,#, Xiao-ke Wang 3,#, Li-ren Han 1, Hao Li 1, Hui-chao Tian 1, Jun Yan 1,2,*, Hai-juan Liu 4,*
Editor: Amir Human Hoveidaei5
PMCID: PMC11095721  PMID: 38748674

Abstract

Background

Talar fractures often require osteotomy during surgery to achieve reduction and screw fixation of the fractured fragments due to limited visualization and operating space of the talar articular surface. The objective of this study was to evaluate the horizontal approach to the medial malleolus facet by maximizing exposure through dorsiflexion and plantarflexion positions.

Methods

In dorsiflexion, plantarflexion, and functional foot positions, we respectively obtained the anterior and posterior edge lines of the projection of the medial malleolus on the medial malleolar facet. The talar model from Mimics was imported into Geomagic software for image refinement. Then Solidworks software was used to segment the medial surface of the talus and extend the edge lines from the three positions to project them onto the "semicircular" base for 2D projection. The exposed area in different positions, the percentage of total area it represents, and the anatomic location of the insertion point at the groove between the anteroposternal protrusions of the medial malleolus were calculated.

Results

The mean total area of the "semicircular" region on the medial malleolus surface of the talus was 542.10 ± 80.05 mm2. In the functional position, the exposed mean area of the medial malleolar facet around the medial malleolus both anteriorly and posteriorly was 141.22 ± 24.34 mm2, 167.58 ± 22.36mm2, respectively. In dorsiflexion, the mean area of the posterior aspect of the medial malleolar facet was 366.28 ± 48.12 mm2. In plantarflexion, the mean of the anterior aspect of the medial malleolar facet was 222.70 ± 35.32 mm2. The mean overlap area of unexposed area in both dorsiflexion and plantarflexion was 23.32 ± 5.94 mm2. The mean percentage of the increased exposure area in dorsiflexion and plantarflexion were 36.71 ± 3.25% and 15.13 ± 2.83%. The mean distance from the insertion point to the top of the talar dome was 10.69 ± 1.24 mm, to the medial malleolus facet border of the talar trochlea was 5.61 ± 0.96 mm, and to the tuberosity of the posterior tibiotalar portion of the deltoid ligament complex was 4.53 ± 0.64 mm.

Conclusions

Within the 3D model, we measured the exposed area of the medial malleolus facet in different positions and the anatomic location of the insertion point at the medial malleolus groove. When the foot is in plantarflexion or dorsiflexion, a sufficiently large area and operating space can be exposed during surgery. The data regarding the exposed visualization area and virtual screws need to be combined with clinical experience for safer reduction and fixation of fracture fragments. Further validation of its intraoperative feasibility will require additional clinical research.

Introduction

Talar fractures are relatively uncommon, accounting for less than 1% of all fractures, and comprising only 3% to 6% of fractures in the foot and ankle [1]. The talus is composed of a head, neck, and body, with an extremely irregular shape, and the majority of it is covered by articular cartilage [2]. Most talar fractures are caused by violent trauma such as falls from height or car accidents [3]. Furthermore, talar fractures are often associated with ankle fractures, severe soft tissue damage, calcaneal fractures, and metatarsal fractures. These can disrupt the ankle joint’s mobility system and lead to complications such as ischemic necrosis, arthritis and deformities [3–7]. Therefore, talar fractures should be stabilized, anatomically reduced, and firmly fixed as early as possible [8, 9].

Talar body fractures account for 7% to 38% of all talar fractures and are one of the most challenging foot and ankle procedures [7, 10]. The structure of the talar body is unique, its upper surface connects to the tibial plafond, and it extends laterally to attach to the medial and lateral malleoli [2, 5]. Such complex anatomy hinders the exposure, reduction, and fixation of the fractured fragments during surgery [11]. Previous studies have typically employed osteotomy of the medial or lateral malleolus in the treatment of talar body fractures to maximize the exposure of the talus’ upper articular surface, especially in cases of comminuted and displaced fractures [4, 7, 12, 13]. However, in our surgical experience with talar procedures, we have found that when the foot is maximally dorsiflexed or plantarflexed, it is possible to expose a significant portion of the medial malleolar facet. In some cases of talar body sagittal fractures, screw fixation may be achieved without the need for osteotomy. This study was designed to evaluate the horizontal approach to the medial malleolus surface in sagittal talar fractures through dorsiflexion and plantarflexion.

Materials and methods

We prospectively recruited 91 adults patients who underwent postoperative follow-up for unilateral lower limb fractures. Dual lower limb consecutive CT scans were performed, with the unaffected side foot maintaining functional position, maximal dorsiflexion, and maximal plantarflexion, each undergoing one CT scan at the imaging research center of our hospital during December 2022 and June 2023, including 38 females and 53 males. Patients were excluded if they had deformity, fracture, arthritis, or tumor in the foot. This study was conducted in accordance with the World Medical Association Declaration of Helsinki and approved by the Ethical Committee of Liaocheng People’s Hospital (No. 2021033). Written informed consent was obtained from all patient who participated in this study (includes patient with traction as shown in Fig 4). The mean age of the patients on whom the models were based was 41.47 ± 14.98 years (range, 18–74 years).

Fig 4. After applying traction, the joint space widens (red lines).

Fig 4

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A In the neutral position (no traction). B In the neutral position (with traction). C In the lateral position (no traction). D In the lateral position (with traction).

DICOM-formatted CT-scan images of each patient were imported into Mimics software (21.0; Materialise, Leuven, Belgium). We removed the soft tissue and affected bones by the function of image segmentation, region growth and multiple slice editing of Mimics software, respectively. A total of 273 virtual foot and ankle models were created. In dorsiflexion, plantarflexion, and functional foot positions, we respectively obtained the anterior and posterior edge lines of the projection of the medial malleolus on the medial malleolar facet (Fig 1). At the same time, we found that the medial malleolar facet had a shape resembling a “semicircle”, and regardless of whether the foot was in the functional position, dorsiflexed, or plantarflexed, the movement of the medial malleolus occurred within this "semicircular" region (Fig 2A). Tracing the outline of the foot in the three positions on the talus, it is not difficult to observe that plantarflexion and dorsiflexion expand the exposure area on the anterior and posterior aspects of the talus (Fig 2B). The talar model from Mimics was imported into Geomagic software (2019, 3D Systems, North Carolina, USA) for image refinement. Then Solidworks software (2021, Dassault Systemes, USA) was used to segment the medial surface of the talus and extend the edge lines from the three positions to project them onto the "semicircular" base for 2D projection. The following areas were measured: Total area (TA) of the "semicircular" region on the medial malleolar facet; In the functional position, the exposed area of the medial malleolar facet around the medial malleolus both anteriorly (FAA) and posteriorly (FAP); In dorsiflexion, the exposed area of the posterior aspect of the medial malleolar facet (DA); In plantarflexion, the exposed area of the anterior aspect of the medial malleolar facet (PA); Unexposed overlap area in both dorsiflexion and plantarflexion (UA). The percentage of the increased exposure area in dorsiflexion and plantarflexion positions were calculated.

Fig 1. The anterior and posterior edge lines of the projection of the medial malleolus on the medial surface of the talus (red lines).

Fig 1

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A In the functional position, the anterior edge lines of the projection of the medial malleolus. B In the functional position, the posterior edge lines of the projection of the medial malleolus. C In dorsiflexion, the posterior edge lines of the projection of the medial malleolus. D In plantarflexion, the anterior edge lines of the projection of the medial malleolus.

Fig 2. The measurement of exposed area of medial malleolar facet.

Fig 2

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A The "semicircular" area of the medial malleolar facet. B The projected lines on the medial malleolus facet in the three positions (Black-Functional position; Red-Plantarflexion position; Green-Dorsiflexion position).

In addition, in the functional position, we observed that the groove between the anteroposternal protrusions of the medial malleolus was closer to the center of the medial malleolar facet. This groove could potentially serve as the insertion point for screw fixation (Fig 3A). To determine the anatomic location of the insertion point on the medial malleolar facet, a virtual screw was inserted into the talar model and the distances were measured: the distance of the insertion point to the top of the talar dome (L1), the distance of the medial malleolus facet border of the talar trochlea (red line, L2), and the distance from the insertion point to the tuberosity of the posterior tibiotalar portion of the deltoid ligament complex (L3), respectively (Fig 3B).

Fig 3. The measurement of virtual screws in the model.

Fig 3

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A The insertion point of the virtual screw is within the groove between the anteroposternal protrusions of the medial malleolus. B Anatomic location of virtual screw (L1: the distance of the insertion point to the top of the talar dome; L2: the distance of the insertion point to the medial malleolus facet border of the talus trochlea; L3: the distance of the insertion point to the tuberosity of the posterior tibiotalar portion of the deltoid ligament complex).

The collected data were analysed by SPSS 25.0 statistical software. The experimental data are represented as the mean ± standard deviation. The independent sample T test was used to compare the genders. Statistical significance was accepted at P < 0.05.

Results

The study subjects included 53 males and 38 females aged between 18 and 74 years old, with a mean age of 41.47 ± 14.98 years.

As shown in Table 1, the mean total area of the "semicircular" region on the medial surface of the talus was 542.10 ± 80.05 mm2; In the functional position, the exposed mean area of the medial surface of the talus around the medial malleolus both anteriorly and posteriorly was 141.22 ± 24.34 mm2, 167.58 ± 22.36mm2. For the data captured above, the exposed mean area (TA, FAA, FAP) of the intersex difference was significant (P<0.05). In dorsiflexion, the mean area of DA was 366.28 ± 48.12 mm2; In plantarflexion, the mean of PA was 222.70 ± 35.32 mm2; The mean area of UA was 23.32 ± 5.94 mm2. For the data captured above, the exposed mean area (DA, PA, UA) of the intersex difference was significant (P<0.05). However, in dorsiflexion, the mean percentage of the increased exposure area was 36.71 ± 3.25%, and in plantarflexion, the mean percentage of the increased exposure area was 15.13 ± 2.83%, fom Table 1, the results were not statistically significant between males and females (P>0.05).

Table 1. Comparison between different genders: Average TA, FAA, FAP, DA, PA, UA, (DA-FAP)/TA and (PA-FAA)/TA.

Group TAy (mm2) FAAy (mm2) FAPy (mm2) DAy (mm2) (DA-FAP)/TA (%) PAy (mm2) (PA-FAA)/TA (%) UAy (mm2)
All (n = 91) 542.10±80.05 141.22±24.34 167.58±22.36 366.28±48.12 36.71±3.25 222.70±35.32 15.13±2.83 23.32±5.94
Male (n = 53) 599.37±68.81 158.62±20.39 179.29±23.63 399.13±49.11 36.51±3.26 248.12±33.88 14.94±3.25 28.511±4.23
Female (n = 38) 490.03±47.89 125.39±15.25 156.95±15.38 336.42±20.03 36.90±3.40 199.60±15.12 15.31±2.53 18.60±1.73
t valuex 4.261 4.256 2.593 3.902 -0.262 4.310 -0.292 7.155
P valuex 0.001 <0.001 0.018 0.001 0.796 <0.001 0.773 <0.001
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xt and P are the results of gender comparisons

yFor the area of TA, FAA, FAP, DA, PA, and UA intersex difference was significant (P < 0.05)

From Table 2, the mean distance L1 was 10.69 ± 1.24 mm, L2 was 5.61 ± 0.96 mm, and L3 was 4.53 ± 0.64 mm, respectively. For the data captured above, the distance (L1, L2, L3) of the intersex difference was significant (P<0.05).

Table 2. Comparison between different genders: Average L1, L2, L3.

Group L1y (mm) L2y (mm) L3y (mm)
All (n = 91) 10.69±1.24 5.61±0.96 4.53±0.64
Male (n = 53) 11.39±1.20 6.16±0.81 4.88±0.62
Female (n = 38) 10.06±0.91 5.11±0.82 4.21±0.49
t valuex 2.863 2.926 2.724
P valuex 0.010 0.009 0.013
Open in a new tab

xt and P are the results of gender comparisons

yFor the distance of L1, L2 and L3, intersex difference was significant (P < 0.05)

Discussion

In our research, the areas of the TA, FAA, FAP, DA, PA, UA were significantly larger in males compared with females. This may be due to anatomical differences in the bone size between females and males [14, 15]. From Table 1, The exposed area on the medial malleolar surface of the talus significantly increases when the foot was in dorsiflexion or plantarflexion, and the increased area in plantarflexion accounted for one-third of the total talar area. In conjunction with Fig 1, when there is a sagittal fracture of the talar body, it is entirely feasible to use screws to fix the fracture fragments separately in dorsiflexion and plantarflexion. The extensive exposure in dorsiflexion provides a sufficient distance from the deltoid ligament complex, the artery of the tarsal canal, the posterior tibial artery, and tibial nerve when performing screw fixation, ensuring an ample and safe operating space [4]. As shown in Fig 1, In dorsiflexion and plantarflexion, the joint becomes locked, increasing the contact area of the joint and providing ample exposure of the talus articular surface. Increased exposure, sufficient space, and joint locking; these factors are advantageous for the reduction of displaced fracture fragments. For fracture patients, there may be damage to the deltoid ligament complex the tibialis anterior, the tibialis posterior, the flexor hallucis longus, and the flexor digitorum longus [3, 10]. Additionally, muscle relaxation under anesthesia can lead to a larger surgical exposure area, which is beneficial for improving the visualization of the fracture fragments [16]. DeKeyser et al demonstrated that the posterior medial and posterior lateral approaches can increase the exposure area of the talar dome with traction [17, 18]. Therefore, applying traction during the operation can further increase the operating space. As shown in Fig 2B and Table 1, the area not exposed in dorsiflexion and plantarflexion are relatively small, and will further diminish or even disappear during traction.

From Fig 3B, we found that the insertion point at the groove between the anteroposternal protrusions of the medial malleolus is not directly beneath the highest point of the talar dome. However, it is within the space exposed during dorsiflexion. When visualizing screw fixation at this location is limited in the functional position, increasing the operating space can be achieved by transitioning to dorsiflexion. During the operation, under lead shielding for protection, two operators manually applied traction to the talus in both the neutral position and lateral position. It can be observed that the joint space between the talus and tibia widens, and the insertion point also will moves closer to the center of the talar body accordingly (Fig 4). Building upon the research of DeKeyser et al, applying posterior-inferior traction during dorsiflexion will further expand the visualization area, allowing for screw placement closer to the center of the talar body to achieve maximum holding force for fixing the fractured fragments. As shown from Table 2, the distances of the L1, L2, L3 were significantly larger in males compared with females. This may be due to anatomical differences in the bone size between females and males [14, 15].

This study evaluated the horizontal approach to the medial malleolus surface in sagittal talar fractures through dorsiflexion and plantarflexion. The findings demonstrate a significant increase in the exposure area of the medial malleolus facet in both dorsiflexion and plantarflexion positions. Moreover, under anesthesia and traction during surgery, there is a notable enhancement in the visualization of the talus. This may facilitate the reduction and screw fixation of fracture fragments without osteotomy, thereby reducing patient trauma associated with the surgery.

There are still some limitations to this study. We only analyzed the data based on genders, not different age, body size and type of fracture groups. These factors may also affect the visualization of the medial malleolus facet and the positioning of screws. In addition, the study was performed on intact tali, but the normal anatomy is distorted in the case of talar fractures. It is necessary to improve the quality of fracture reduction by preoperative 3D reconstruction and intraoperative use of reduction forceps. Furthermore, we lack a sufficient number of cadaveric specimens to verify the exposed area of the medial malleolus facet in different positions and the operational space for reduction and screw placement during surgery. More relevant clinical studies are needed to confirm these findings.

Conclusion

We provide guidelines for the horizontal approach to the medial malleolus facet in sagittal talar fractures in a 3D simulation. Within the 3D model, we measured the exposed area of the medial malleolus facet in different positions and the anatomic location of the insertion point at the medial malleolus groove. The data regarding the exposed visualization area and virtual screws need to be combined with clinical experience for safer reduction and fixation of fracture fragments. Further validation of its intraoperative feasibility will require additional cadaveric specimens research and clinical studies.

Supporting information

S1 Data. Minimum data set.

(DOCX)

pone.0295350.s001.docx (13.8KB, docx)

Data Availability

All relevant datasets for this study are publicly available from the Dryad repository (https://doi.org/10.5061/dryad.r7sqv9skk).

Funding Statement

This study was financially supported by the National Natural Science Foundation of ShanDong Province in the form of a grant (ZR202102280280) received by JY. The grant funds allocated for this study were specifically used to collect CT scans. No additional external funding was received for this study.

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Decision Letter 0

Amir Human Hoveidaei

14 Dec 2023

PONE-D-23-36659Evaluation of the horizontal approach to the medial malleolar facet in sagittal talar fractures through dorsiflexion and plantarflexion positions.PLOS ONE

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Reviewer #1: Thank you for the opportunity to review this interesting article on medial malleolar approaches to sagittal talar fractures. This seems to be a novel addition to the literature with impressive methods and results.

There are many grammatical/punctuation errors which will need to be addressed prior to publication. Please revise semicolon usage. Also, “in plantarflexion” is correct whereas “in plantarflexion position” is not. “In the plantarflexion position” is correct as well.

Please find my revisions below with corresponding line numbers:

33-35: change to “The talar model from Mimics was imported into Geomagic software for image refinement. Then Solidworks software was used to segment the medial surface of the talus and extend the 35 edge lines from the three positions to project them onto the "semicircular" base for 2D projection”. This can be edited for clarity as well.

39-50: Replace semicolons with periods (check for whole section for punctuation errors)

42: add “, respectively”

42: remove “position”

62: please standardize either “foot-and-ankle” or “foot and ankle” throughout the manuscript

64: should be “falls”

68: please elaborate on “etc” or remove

68: add comma after reduced

71: delete “surgeries in”

78: The foot cannot be dorsiflexed and plantarflexed at the same time. Please clarify - replace “and” with “or”

87: were patients retrospectively or prospectively recruited? Please clarify

94: Was consent obtained for all patients? Or just the one whose radiographs are in figure 4? If all patients please updated the text. If only figure 4 please change the text to explain it that it is the one patient whose radiographs are displayed in the manuscript.

95: what does “all methods were carried out in accordance with relevant guidelines”? Which methods and what guidelines?

96: should be formatted “(range, 18-74 years)” please correct for the rest of the manuscript

108-111: make changes suggested in my comment for lines 33-35

119: should be “in the functional position” correct if this error is found elsewhere in the manuscript

123: replace “measured the distances” with “the distances were measured”

124: write “the distance of the medial malleolar facet border …” … “(red line, L2), and the distance from the insertion point to the tuberosity of the medial malleolus facet …”

125: put the L1, L2, L3 as (L1) after the description. Ex: “from the insertion point to the top of the talar dome (L1), …”

125: I don’t think I’ve seen this wording before: tuberosity of medial malleolus facet of deltoid ligament posterior tibial talar. Please explain and re-word. Is this the posterior tibiotalar portion of the deltoid ligament complex? (Change this phrasing in wherever else it is applicable ex: Fig 3)

128: write out standard deviation instead of “SD”

128: what kind of T test? Student t-test? Wilcoxin sign-rank? T tests were used to compare what data?

138, 141, 146: in what manner was the intersex difference significant? Please elaborate. Intersex difference in area?

152-153: needs citation. Also, what are the differences between female and male? Also it should be “females and males” in the text

157-159: needs citation. What tendons, nerves, and vessels may be in the way.

161: which factors? Please elaborate

162-164: need citations. which tendons? Which muscles? Provide study citation for muscle relaxation leading to greater exposure area.

174-175: informed consent statement disrupts flow of discussion, remove (assuring that it can be found in the methods section)

181: replace obviously - too informal

182-183: As with 152-153, please describe the differences with literature. Also it should be “females and males” in the text

188-190: please cite literature on the reduced economic burden

193-194: please cite literature to support your claim that “Chinese people … have different skeletal shapes with American and European populations.” Also it should be different shapes “than”

195: plural of talus is tali, please update text

196-197: please elaborate on what is meant by “It is necessary to improve the quality of fracture reduction by preoperative 3D reconstruction and intraoperative use of reduction forceps.” How does this fit into the limitations section?

Reviewer #2: This study presents a commendable and insightful approach to a complex subject. However, I would like to offer some suggestions to enhance the clarity and impact of the paper.

Abstract:

Line 46: This sentence requires correction for better clarity. Additionally, it would be beneficial to include information about UA in the abstract.

Line 51: In the conclusion part of the abstract, it's essential to explicitly mention the findings related to your horizontal approach, as it is central to the study.

Introduction:

The introduction is well-written and sets a strong foundation for the study.

Methods:

Consider organizing the Methods section into clearly defined subsections. This would greatly enhance the readability and logical flow of the paper.

Some content in the Methods section appears to pertain to the Results. Please review and relocate these sentences to the appropriate section.

Results:

For a more comprehensive analysis, consider using the proportion of each variable relative to the total talus surface area. This adjustment could account for variations in talus size due to factors like height and gender.

Lines 141-144 require rewriting for better clarity and coherence.

Discussion:

It would be advantageous to start the discussion with the study's most significant findings, as this sets the tone and focus for the rest of the discussion.

The section discussing limitations is well-articulated.

Conclusion:

The conclusion is well-formed and effectively summarizes the study.

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6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

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Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: Yes: Mohammad Poursalehian

**********

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Decision Letter 1

Amir Human Hoveidaei

26 Feb 2024

PONE-D-23-36659R1Evaluation of the horizontal approach to the medial malleolar facet in sagittal talar fractures through dorsiflexion and plantarflexion positions.PLOS ONE

Dear Dr. Yan,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Apr 11 2024 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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  • An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Amir Human Hoveidaei

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Additional Editor Comments:

Dear authors,

Many thanks for submitting the paper. Based on the reviewer comments we can accept after minor revisions.

Best,

Amir H Hoveidaei, MD, MSc

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: (No Response)

Reviewer #2: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Thank you for the opportunity to once again review this compelling article. At this time I believe that there remains some minor revisions before this article is acceptable for publication. Please find below my review.

Whole article: There should be spaces before parenthesis “ (“

Abstract:

34: change to “In dorsiflexion, plantarflexion, and functional foot positions” and make sure this grammatical correction is applied to other instances. On line 110 “in the functional position, dorsiflexed, or plantarflexed” is also an acceptable way to phrase this.

36: delete extra period

Introduction:

67: change all instances of “foot-and-ankle” to “foot and ankle”

72: should be “and deformities”

102: space before “years”

Results:

169: remove and replace obviously with formal language

Table 1: improve formatting for reader

189, Reference 14: this is a study on a pediatric population, however this study has a mean age of approx. 45, please find literature that represents the patients in your study.

198: change comma after “locking” to ; or –

199-203: run on sentence, please split into 2 sentences. “Additionally” should be the start of the second sentence. And please make sure that there are citations for the claims made in the first sentence.

219-220: same claim as 189. See above.

234: change talus to tali

235: be more specific than “skeletal shapes”. The shapes of which bones? What is the shape difference? What about the bone micro-architecture is different? Or remove sentence entirely.

Reviewer #2: (No Response)

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: Yes: Mohammad Poursalehian

**********

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Decision Letter 2

Amir Human Hoveidaei

11 Mar 2024

Evaluation of the horizontal approach to the medial malleolar facet in sagittal talar fractures through dorsiflexion and plantarflexion positions.

PONE-D-23-36659R2

Dear Dr. Yan,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at http://www.editorialmanager.com/pone/ and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Amir Human Hoveidaei, MD, MSc

Academic Editor

PLOS ONE

Acceptance letter

Amir Human Hoveidaei

30 Apr 2024

PONE-D-23-36659R2

PLOS ONE

Dear Dr. Yan,

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team.

At this stage, our production department will prepare your paper for publication. This includes ensuring the following:

* All references, tables, and figures are properly cited

* All relevant supporting information is included in the manuscript submission,

* There are no issues that prevent the paper from being properly typeset

If revisions are needed, the production department will contact you directly to resolve them. If no revisions are needed, you will receive an email when the publication date has been set. At this time, we do not offer pre-publication proofs to authors during production of the accepted work. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few weeks to review your paper and let you know the next and final steps.

Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

If we can help with anything else, please email us at customercare@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Amir Human Hoveidaei

Academic Editor

PLOS ONE

Associated Data

    This section collects any data citations, data availability statements, or supplementary materials included in this article.

    Supplementary Materials

    S1 Data. Minimum data set.

    (DOCX)

    pone.0295350.s001.docx (13.8KB, docx)
    Attachment

    Submitted filename: Response to Reviewers.doc

    pone.0295350.s002.doc (69.5KB, doc)
    Attachment

    Submitted filename: Response to Reviewers.doc

    pone.0295350.s003.doc (31KB, doc)

    Data Availability Statement

    All relevant datasets for this study are publicly available from the Dryad repository (https://doi.org/10.5061/dryad.r7sqv9skk).

    Articles from PLOS ONE are provided here courtesy of PLOS

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