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Cited by 16Hip disorders and treatmentsLower Extremity Biomechanics and PathologiesOrthopaedic implants and arthroplasty

The DOI matches its Crossref record; 24 of the 24 references it cites were found in a registry or an index; 15 of the 20 sources its claims cite were checked for support.

Femoral head translation in borderline and definite dysplastic hips during weight‐bearing: 2D/3D image registration analysis

Open access
Sakai, Shinichiro, Kutsuna, Tatsuhiko, Kono, Kohei, Kinoshita, Tomofumi, Mashima, Naohiko, Takao, Masaki·2023·Journal of Experimental Orthopaedics
DOI 10.1186/s40634-023-00707-8PMC PMC10686934
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Abstract

Abstract Purpose The aims of this study were to 1) assess femoral head translation during weight‐bearing in symptomatic developmental dysplasia of the hip (DDH) and 2) compare it between borderline DDH and definite DDH. Methods The study included four individuals with borderline DDH and nine with definite DDH, scheduled for periacetabular osteotomy. Anteroposterior X‐ray images of the hip joint were obtained in the standing position, and computed tomography images of the pelvis were obtained in the supine position. Femoral head translation from the supine to a standing position was measured using 2D/3D X‐ray image registration. Results From a supine to a standing position, the femoral head translated 0.3 mm laterally, 0.5 mm anteriorly, and 0.5 mm superiorly on average. The mean femoral head translation in 3D between the supine and standing positions was 1.5 mm. The 3D femoral head translation in the borderline DDH group was significantly greater than that in the definite DDH group. In the definite DDH group, there was a significant correlation between the center edge (CE) angle and 3D femoral head translation ( ρ = ‐0.78, P = 0.012). Conclusions Symptomatic DDH showed femoral head translation in the anterior, lateral, and superior directions during weight‐bearing. In definite DDH, the amount of femoral head translation was negatively correlated with the CE angle. The amount of 3D translation in patients with borderline DDH was larger than that in definite DDH. Dynamic joint instability during weight‐bearing was observed in borderline DDH as well as definite DDH. Treatment to enhance joint stability during weight‐bearing is important in both cases.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

In symptomatic developmental dysplasia of the hip (DDH), the femoral head translates anteriorly, laterally, and superiorly during weight-bearing, with a mean 3D translation of 1.5 mm from supine to standing. Borderline DDH showed greater 3D translation than definite DDH, and in definite DDH translation was negatively correlated with the center edge (CE) angle.

Key findings

  • From supine to standing, the femoral head translated 0.3 mm laterally, 0.5 mm anteriorly, and 0.5 mm superiorly on average; mean 3D femoral head translation was 1.5 mm.
  • 3D femoral head translation was significantly greater in borderline DDH than in definite DDH (2.2 mm vs 1.2 mm).
  • In definite DDH, the CE angle correlated with 3D femoral head translation (ρ = -0.78, P = 0.012); all morphological parameters except PASA and FEAR index showed significant correlations with 3D translation in this group.
  • No morphological factors were correlated with 3D femoral head translation among all subjects. Postoperative JOA scores improved from 74 to 98 in borderline DDH and from 74 to 96 in definite DDH.

Methods

  • Prospective cohort study of 13 symptomatic hips from 13 patients with DDH who underwent rotational acetabular osteotomy; 4 hips were classified as borderline DDH (18° ≤ CE angle < 25°) and 9 as definite DDH (CE angle < 18°).
  • Standing anteroposterior hip X-rays and supine pelvic CT images were used; femoral head translation from supine to standing was measured with 2D/3D X-ray image registration, using the anterior pelvic plane coordinate system.
  • An in vitro porcine hip validation study assessed registration accuracy; statistical comparisons used Student’s t-test or Mann–Whitney U test, and correlations used Pearson or Spearman coefficients, with P < 0.05.

Limitations

  • Stated by the authors: no normal hip control was evaluated to avoid radiation exposure; the definition of borderline dysplasia remains unclear (they used 18° ≤ CE angle < 25°, while 20° ≤ CE angle < 25° is also common); the number of cases was small despite meeting the power analysis minimum; and the measured translations were small relative to the method’s accuracy, with in vitro validation indicating measurement accuracy of < 1 mm.
  • Evident from the text: all participants were female, so findings may not generalize to male patients; the study assessed supine-to-standing translation rather than dynamic gait or other weight-bearing activities.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1186/s40634-023-00707-8

Cites

24 of 24 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

15 of 20 cited sources checked · 10 supported · 1 flagged · accuracy not yet measured

  • Premisecitation

    Stress concentration on the limited articular surface for weight-bearing and dynamic joint instability are considered significant biomechanical factors that cause joint degeneration in younger patients.

    “Stress concentration on the limited articular surface for weight-bearing and dynamic joint instability are considered significant biomechanical factors that cause joint degeneration in younger patients [9].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [9] Henak CR Abraham CL Anderson AE Maas SA Ellis BJ Peters CL Patient-specific analysis of cartilage and labrum mechanics in human hips with acetabular dysplasia Osteoarthritis Cartilage 2014 22 210 217 10.1016/j.joca.2013.11.003 24269633 PMC3946188 source

      The Introduction links acetabular dysplasia and altered hip mechanics to osteoarthritis, but the Discussion expressly rejects increased cartilage contact stress as the explanation found in this study: the labrum carries much of the load, and cartilage stresses in dysplastic hips were not increased relative to normal hips. The paper does not establish dynamic joint instability as a cause of degeneration in younger patients. No page numbers are available in our copy. (LLM, conf=0.86)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
  • Premisecitation

    Few studies have evaluated the in vivo dynamic instability in DDH during weight-bearing.

    “However, few studies have evaluated the in vivo dynamic instability in DDH during weight-bearing [1, 18].”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites [1] Akiyama K Sakai T Koyanagi J Yoshikawa H Sugamoto K Evaluation of translation in the normal and dysplastic hip using three-dimensional magnetic resonance imaging and voxel-based registration Osteoarthritis Cartilage 2011 19 700 710 10.1016/j.joca.2011.01.017 21315165 source

      The Introduction says there have been few in vivo studies of hip instability, supporting the scarcity claim. The Discussion describes an earlier gait-cycle study, but does not establish that the few studies evaluated instability specifically during weight-bearing; it also says this paper's own MRI measurements were static and could not assess functional effects during daily activities. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [18] Sato T Tanino H Nishida Y Ito H Matsuno T Banks SA Dynamic femoral head translations in dysplastic hips Clin Biomech 2017 46 40 45 10.1016/j.clinbiomech.2017.05.003 28501788 source
  • Study design and conductcitation

    The degree of femoral head translation during weight-bearing was small compared with the measurement accuracy of the computational 2D/3D image registration method.

    “Finally, the degree of femoral head translation during weight-bearing was small compared with the measurement accuracy of our computational 2D/3D image registration method (root mean square error of 0.2 mm in translation and 0.2° in rotation in porcine patellar bones [11]).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [11] Ishimaru M Shiraishi Y Ikebe S Three-dimensional motion analysis of the patellar component in total knee arthroplasty by the image matching method using image correlations J Orthop Res 2014 32 619 626 10.1002/jor.22596 24522960 source
    • Rests on an assumption: The 2D/3D image registration method's accuracy, validated in vitro on porcine bones, applies to in vivo human DDH hips.
  • Interpretationown data

    The values of femoral head translation during weight-bearing in DDH are similar to those reported in previous studies on dynamic instability of definite DDH.

    “In this study, the femoral head translation during weight-bearing in DDH ranged from 0.5 to 2.3 mm, similar values to those reported in previous studies on dynamic instability of definite DDH [1, 18].”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites [1] Akiyama K Sakai T Koyanagi J Yoshikawa H Sugamoto K Evaluation of translation in the normal and dysplastic hip using three-dimensional magnetic resonance imaging and voxel-based registration Osteoarthritis Cartilage 2011 19 700 710 10.1016/j.joca.2011.01.017 21315165 source

      The Results report millimetre-scale femoral-head translation in dysplastic hips, including 0.76–2.39 mm from neutral to flexion. But the Discussion says the measurements came from static MRI positions and could not evaluate functional effects during daily activity. The paper therefore supports a similarity in magnitude, not translation measured during weight-bearing or dynamic instability. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [18] Sato T Tanino H Nishida Y Ito H Matsuno T Banks SA Dynamic femoral head translations in dysplastic hips Clin Biomech 2017 46 40 45 10.1016/j.clinbiomech.2017.05.003 28501788 source
    • Rests on an assumption: The 2D/3D image registration method's accuracy, validated in vitro on porcine bones, applies to in vivo human DDH hips.
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.
  • Premisecitation

    The image-matching method had a root mean square error of 0.2 mm in translation and 0.2° in rotation when measuring the patellar bone of a fresh-frozen porcine knee joint.

    “The accuracy of measurements of the patellar bone of a fresh-frozen porcine knee joint yielded a root mean square error of 0.2 mm in translation and 0.2° in rotation [11].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [11] Ishimaru M Shiraishi Y Ikebe S Three-dimensional motion analysis of the patellar component in total knee arthroplasty by the image matching method using image correlations J Orthop Res 2014 32 619 626 10.1002/jor.22596 24522960 source
  • It may state two separate claims as one. 10
  • Probably not a substantial claim. 9
  • The quote only partly states this claim. 2

  • It may state two separate claims as one.

    Interpretationcitation

    The CE angle was the determinant for 3D-translation from the neutral to the Patrick position in Akiyama et al., which coincides with our results for definite DDH.

    “The CE angle was the determinant for 3D-translation from the neutral to the Patrick position, which coincides with our results for definite DDH.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [1] Akiyama K Sakai T Koyanagi J Yoshikawa H Sugamoto K Evaluation of translation in the normal and dysplastic hip using three-dimensional magnetic resonance imaging and voxel-based registration Osteoarthritis Cartilage 2011 19 700 710 10.1016/j.joca.2011.01.017 21315165 source
    • Rests on an assumption: The 2D/3D image registration method's accuracy, validated in vitro on porcine bones, applies to in vivo human DDH hips.
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • It may state two separate claims as one.

    Interpretationcitation

    Regression analyses in Sato et al. showed significant correlations between maximum femoral head translation and the CE angle, AHI, and ARO, which coincides with our results for definite DDH.

    “Regression analyses showed significant correlations between maximum femoral head translation and the CE angle, AHI, and ARO, which coincides with our results for definite DDH.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [18] Sato T Tanino H Nishida Y Ito H Matsuno T Banks SA Dynamic femoral head translations in dysplastic hips Clin Biomech 2017 46 40 45 10.1016/j.clinbiomech.2017.05.003 28501788 source
    • Rests on an assumption: The 2D/3D image registration method's accuracy, validated in vitro on porcine bones, applies to in vivo human DDH hips.
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • Probably not a substantial claim.

    Premisecitation

    Hip joint stabilization relies on acetabular bony coverage and integrity of soft tissues, including the acetabular labrum, ligamentum teres, and capsular structures.

    “Hip joint stabilization relies on acetabular bony coverage and integrity of soft tissues, including the acetabular labrum, ligamentum teres, and capsular structures [13].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [13] Kalisvaart MM Safran MR Microinstability of the hip-it does exist: etiology, diagnosis and treatment J Hip Preserv Surg 2015 2 123 135 10.1093/jhps/hnv017 27011829 PMC4718498 source

  • Probably not a substantial claim. It may state two separate claims as one.

    Premisecitation

    Dynamic instability of the hip joint is characterized by excessive femoral head translation within the acetabulum, determined by bone morphology and integrity and laxity of surrounding soft tissues.

    “Dynamic instability of the hip joint is characterized by excessive femoral head translation within the acetabulum [16], which is determined by the bone morphology and integrity and laxity of surrounding soft tissues, including the labrum, capsular-ligamentous complex, and ligamentous teres.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [16] Neira A Amenabar T Cristi-Sanchez I Evaluation of atraumatic hip instability measured by triaxial accelerometry during walking J Hip Preserv Surg 2019 6 134 139 10.1093/jhps/hnz018 31660198 PMC6662898 source

  • Probably not a substantial claim. It may be too vague to check against evidence.

    Premisecitation

    The optimal evaluation method of dynamic hip instability remains unclear.

    “Much previous research has debated the morphological characteristics to diagnose hip instability; however, the optimal evaluation method of dynamic hip instability remains unclear [2, 4, 17, 20, 22, 23].”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [2] Batailler C Weidner J Wyatt M Pfluger D Beck M Is the Femoro-Epiphyseal Acetabular Roof (FEAR) index on MRI a relevant predictive factor of instability in a borderline dysplastic hip? Bone Joint J 2019 101-B 1578 1584 10.1302/0301-620X.101B12.BJJ-2019-0502.R1 31787002 source
    • cites [4] Dangin A Tardy N Wettstein M May O Bonin N Microinstability of the hip: a review Orthop Traumatol Surg Res 2016 102 S301 S309 10.1016/j.ostr.2016.09.002 27744000 source
    • cites [17] Packer JD Cowan JB Rebolledo BJ Shibata KR Riley GM Finlay AK The Cliff Sign: A New Radiographic Sign of Hip Instability Orthop J Sports Med 2018 12 6 2325967118807176 10.1177/2325967118807176 PMC6240982 30480017 source

  • It may state two separate claims as one.

    Premisecitation

    Damage to the labrum and cartilage, together with lack of acetabular bony coverage and inherent soft tissue laxity, can contribute to various degrees of dynamic instability of the hip joint and cause progressive osteoarthritic changes.

    “This damage, together with the lack of acetabular bony coverage and inherent soft tissue laxity, can contribute to various degrees of dynamic instability of the hip joint and cause progressive osteoarthritic changes [8, 12, 19].”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [8] Han S Alexander JW Thomas VS Choi J Harris JD Doherty DB Does capsular laxity lead to microinstability of the native hip? Am J Sports Med 2018 46 1315 1323 10.1177/0363546518755717 29505731 source
    • cites [12] Jacobsen S Sonne-Holm S Hip dysplasia: a significant risk factor for the development of hip osteoarthritis A cross-sectional survey Rheumatology (Oxford) 2005 44 211 218 10.1093/rheumtology/keh436 15479751 source

      The Discussion (page unavailable) says reduced load-transferring area in dysplastic hips may lead to degeneration and reports an association between hip dysplasia and osteoarthritis. It does not address labral or cartilage damage, soft-tissue laxity, or dynamic instability as the proposed mechanism. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [19] Smith MV Panchal HB Ruberte Thiele RA Sekiya JK Effect of acetabular labrum tears on hip stability and labral strain in a joint compression model Am J Sports Med 2011 39 Suppl 103S S110 10.1177/0363546511400981 21709039 source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingnone given

    Rotational acetabular osteotomy improved the symptoms of four patients with borderline DDH.

    “Rotational acetabular osteotomy improved the symptoms of four patients with borderline DDH, suggesting that a slight variation in acetabular coverage between normal and borderline dysplastic hips could influence hip instability, but not mechanical stress concentration, in some patients.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • The quote only partly states this claim.

    Findingown data

    The mean 3D femoral head translation between the supine and standing positions was 1.5 mm in symptomatic DDH.

    “The mean femoral head translation in 3D between the supine and standing positions was 1.5 mm.”
    • Also stated in: § In vivo study · plain
      “The mean femoral head translation in 3D between the supine and standing positions was 1.5 mm (Table 2).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The 2D/3D image registration method's accuracy, validated in vitro on porcine bones, applies to in vivo human DDH hips.
    • Rests on an assumption: The supine position provides a neutral reference for measuring femoral head translation.
    • Rests on an assumption: The standing position represents the weight-bearing condition relevant to dynamic hip instability.
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • The quote only partly states this claim.

    Findingown data

    In symptomatic DDH, from a supine to a standing position, the femoral head translated on average 0.3 mm laterally, 0.5 mm anteriorly, and 0.5 mm superiorly.

    “From a supine to a standing position, the femoral head translated 0.3 mm laterally, 0.5 mm anteriorly, and 0.5 mm superiorly on average.”
    • Also stated in: § In vivo study · plain
      “From the supine to standing position, the femoral head translated 0.3 mm laterally, 0.5 mm anteriorly, and 0.5 mm superiorly on average.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The 2D/3D image registration method's accuracy, validated in vitro on porcine bones, applies to in vivo human DDH hips.
    • Rests on an assumption: The supine position provides a neutral reference for measuring femoral head translation.
    • Rests on an assumption: The standing position represents the weight-bearing condition relevant to dynamic hip instability.
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • Probably not a substantial claim.

    Interpretationreasoning

    The degree of inherent joint laxity may influence susceptibility to joint instability.

    “The degree of inherent joint laxity may influence susceptibility to joint instability.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Interpretationreasoning

    Soft tissue laxity, in addition to labral and cartilage damage, can affect hip joint stabilization.

    “Soft tissue laxity, in addition to labral and cartilage damage, can affect hip joint stabilization.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationown data

    Dynamic joint instability during weight-bearing was observed in borderline DDH as well as definite DDH.

    “Dynamic joint instability during weight-bearing was observed in borderline DDH as well as definite DDH.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Femoral head translation measured from the supine to the standing position reflects dynamic joint instability during weight-bearing.
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • It may state two separate claims as one.

    Interpretationown data

    The results suggest that hip bony morphology and inherent soft tissue laxity vary among dysplastic hips, and both contribute significantly to joint stability.

    “The results of this study suggest that hip bony morphology and inherent soft tissue laxity vary among dysplastic hips, both of which contribute significantly to joint stability.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • It may state two separate claims as one.

    Interpretationreasoning

    A slight variation in acetabular coverage between normal and borderline dysplastic hips could influence hip instability, but not mechanical stress concentration, in some patients.

    “Rotational acetabular osteotomy improved the symptoms of four patients with borderline DDH, suggesting that a slight variation in acetabular coverage between normal and borderline dysplastic hips could influence hip instability, but not mechanical stress concentration, in some patients.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • It may state two separate claims as one.

    Interpretationown data

    The finding of greater dynamic hip instability during weight-bearing in borderline DDH than in definite DDH supports the hypothesis that the etiology of borderline DDH is instability.

    “In this study, higher dynamic hip instability during weight-bearing was found more commonly in borderline DDH than in definite DDH, which supports the hypothesis that the etiology of borderline DDH is instability.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Femoral head translation measured from the supine to the standing position reflects dynamic joint instability during weight-bearing.
    • Rests on an assumption: The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

  • Probably not a substantial claim.

    Study design and conductreasoning

    The study did not evaluate femoral head translation during weight-bearing of normal hip joints as a control.

    “First, we did not evaluate femoral head translation during weight-bearing of the normal hip joints as a control to avoid the effects of radiation exposure.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Study design and conductown data

    The number of cases was small, despite being the minimum required number according to the power analysis.

    “Third, the number of cases was small, despite being the minimum required number according to our power analysis.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    The definition of borderline dysplasia remains unclear.

    “Second, the definition of borderline dysplasia remains unclear.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [5] Domb BG Stake CE Lindner D El-Bitar Y Jackson TJ Arthroscopic capsular plication and labral preservation in borderline hip dysplasia: two-year clinical outcomes of a surgical approach to a challenging problem Am J Sports Med 2013 41 2591 2598 10.1177/0363546513499154 23956133 source
    • cites [7] Fukui K Briggs KK Trinidade CAC Philippon MJ Outcomes after labral repair in patients with femoroacetabular impingement and borderline dysplasia Arthroscopy 2015 31 2371 2379 10.1016/j.arthro.2015.06.028 26315056 source

  • It may state two separate claims as one.

    Study design and conductown data

    The 2D/3D X-ray image registration method had translational errors of -0.69 mm (X), 0.21 mm (Y), -0.09 mm (Z) and rotational errors of -0.10° (X), -0.37° (Y), 0.13° (Z) in an in vitro porcine hip validation.

    “The translational and rotational errors of the 2D/3D X-ray image registration were -0.10° and -0.69 mm for the X-axis direction, -0.37° and 0.21 mm for the Y-axis direction, and 0.13° and -0.09 mm for the Z-axis direction, respectively.”
    • Also stated in: § Discussion · hedged
      “The in vitro validation study using porcine hip bones, presented herein, also indicated a measurement accuracy of < 1 mm.”
    Quote in the paperNot a substantial claim
19 of 19

  • The paper relies on this without support.

    Femoral head translation measured from the supine to the standing position reflects dynamic joint instability during weight-bearing.

    “Dynamic joint instability during weight-bearing was observed in borderline DDH as well as definite DDH.”

  • The paper relies on this without support.

    The 2D/3D image registration method's accuracy, validated in vitro on porcine bones, applies to in vivo human DDH hips.

    “At least, we consider that the femoral head translation during weight-bearing in symptomatic DDH could be measured using our computational 2D/3D image registration method.”

  • The paper relies on this without support.

    The supine position provides a neutral reference for measuring femoral head translation.

    “The direction and distance of movement of the femoral head center from the supine to the standing position were measured (Fig. 3).”

  • The paper relies on this without support.

    The standing position represents the weight-bearing condition relevant to dynamic hip instability.

    “Anteroposterior X-ray images of the hip joint were obtained with the patient in the standing position using an X-ray flat panel detector system (FPD, Zexira®; Toshiba, Tokyo, Japan).”

  • The paper relies on this without support.

    The study sample of symptomatic DDH hips is representative of the broader population of symptomatic DDH.

    “In this prospective cohort study, we evaluated 13 symptomatic hips from 13 patients with DDH who underwent rotational acetabular osteotomy between April 2018 and April 2022 at our institution.”
5 of 5

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Mean age differs between the text and Table 1

    Minor

    The text reports a mean age of 30.8 years, while Table 1 reports 29.8 years for the same 13 patients. The ages listed individually in Table 2 average 29.8 years.

  • Borderline-group sex count omits one patient

    Minor

    Table 1 lists four patients in the borderline DDH group but gives its female/male count as 3/0. The text states that all participants were female.

2 of 2

Citations

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. 10.1016/j.ostr.2016.09.002 · DOI

Cited by

Sorted by citations

Related

Metadata

Authors
Sakai, S., Kutsuna, T., Kono, K., Kinoshita, T., Mashima, N., & Takao, M.
Affiliations
  • Department of Bone and Joint Surgery Graduate School of Medicine Shitsukawa Ehime University Ehime 791‐0295 Toon City Japan
  • Ehime University (JP)
Corresponding author
Takao, Masaki
Venue
Journal of Experimental Orthopaedics
Publisher
Wiley
Published
2023-01
Volume
10
Issue
1
Pages
126-126
ISSN
2197-1153 (ISSN-L)
DOI
10.1186/s40634-023-00707-8
PMC
PMC10686934
OpenAlex
W4389147027
Semantic Scholar
6ec98e1348d21d366b4a7b83c7522175e328fafc
Cited by
16
References
22
Citations by year
2026: 1 · 2025: 13 · 2024: 2
FWCI
3.86
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Experimental Orthopaedics (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
Japan Society for the Promotion of Science London (JP18K09104, JP19H01176)
Topics
  • Health Sciences › Medicine › Surgery › Hip disorders and treatments
  • Physical Sciences › Engineering › Biomedical Engineering › Lower Extremity Biomechanics and Pathologies
  • Health Sciences › Medicine › Surgery › Orthopaedic implants and arthroplasty
Keywords
developmental dysplasia of the hip, weight bearing, center-edge angle, 2D-3D registration, periacetabular osteotomy, hip stability

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