The trunk model: a multi-segment approach of the thorax

3D motion anlysis is a tool for evaluating gait and posture parameters in orthopaedic deformities. Spinal desorders are very common in paediatric orthopaedic practice. Recently used motion capture methods are not suitable for modeling the kinematics of the trunk segments. The aim of this study was to develop a kinematic model for the trunk that could be applied to measure segmental motions. In the present model the trunk was divided into three parts: the upper thorax, the lower thorax and the pelvis. 13 healthy volunteers were measured to calculate standard graphs for the segmental movements of the trunk. The distance of the C7-Th10 vertebrea, the sagittal- and frontal plane balance and the intersegmental rotation were evaluated. Results of this study present normative values of the trunk motion and highlight the flexibility of the thorax. Our trunk model provide possibility for segmental modeling the trunk in adolescence posture desorders such as scoliosis, Scheuermann’s kyphosis and also in adult spinal diseases. DOI: 10.17489/biohun/2013/1/1

Tools to Assess the Trustworthiness of Evidence-Based Point-of-Care Information for Health Care Professionals : Systematic Review

10 pp.Background: User-friendly information at the point of care should be well structured, rapidly accessible, and comprehensive. Also, this information should be trustworthy, as it will be used by health care practitioners to practice evidence-based medicine. Therefore, a standard, validated tool to evaluate the trustworthiness of such point-of-care information resources is needed. Objective: This systematic review sought to search for tools to assess the trustworthiness of point-of-care resources and to describe and analyze the content of these tools. Methods: A systematic search was performed on three sources: (1) we searched online for initiatives that worked off of the trustworthiness of medical information; (2) we searched Medline (PubMed) until June 2019 for relevant literature; and (3) we scanned reference lists and lists of citing papers via Web of Science for each retrieved paper. We included all studies, reports, websites, or methodologies that reported on tools that assessed the trustworthiness of medical information for professionals. From the selected studies, we extracted information on the general characteristics of the tools. As no standard, risk-of-bias assessment instruments are available for these types of studies, we described how each tool was developed, including any assessments on reliability and validity. We analyzed the criteria used in the different tools and divided them into five categories: (1) author-related information; (2) evidence-based methodology; (3) website quality; (4) website design and usability; and (5) website interactivity. The percentage of tools in compliance with these categories and the different criteria were calculated. Results: Included in this review was a total of 17 tools, all published between 1997 and 2018. The tools were developed for different purposes, from a general quality assessment of medical information to very detailed analyses, all specifically for point-of-care resources. However, the development process of the tools was poorly described. Overall, seven tools had a scoring system implemented, two were assessed for reliability only, and two other tools were assessed for both validity and reliability. The content analysis showed that all the tools assessed criteria related to an evidence-based methodology: 82% of the tools assessed author-related information, 71% assessed criteria related to website quality, 71% assessed criteria related to website design and usability, and 47% of the tools assessed criteria related to website interactivity. There was significant variability in criteria used, as some were very detailed while others were more broadly defined. Conclusions: The 17 included tools encompass a variety of items important for the assessment of the trustworthiness of point-of-care information. Overall, two tools were assessed for both reliability and validity, but they lacked some essential criteria for the assessment of the trustworthiness of medical information for use at the point-of-care. Currently, a standard, validated tool does not exist. The results of this review may contribute to the development of such an instrument, which may enhance the quality of point-of-care information in the long term. Trial Registration: PROSPERO CRD42019122565; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=12256

Subject-specific musculoskeletal models and gait characteristics are essential to estimate hip loading for total hip replacement patients

Heupbelasting speelt een rol in de ontwikkeling van osteoartrose en beïnvloedt het proces van botremodellering en osseointegratie van het implantaat na het plaatsen van een totale heupprothese (THP). Dit doctoraatsproject behandelt de kwantificatie van de belasting van het heupgewricht (pre-operatief) en het implantaat (post-operatief) tijdens het gaan, en dit met behulp van biomechanische analysemethoden. Gepersonaliseerde musculoskeletale modelleringstechnieken in combinatie met inverse dynamische simulaties worden gebruikt voor de identificatie van factoren gerelateerd aan gangkarateristieken enerzijds en musculoskeletale geometrie anderzijds, die bepalend zijn voor de belasting van het heupgewricht. Een beter inzicht in deze factoren is essentiëel voor de optimalisatie van chirurgische planning en revalidatie. Dit doctoraatsproject omvat vier deelstudies, die elk de volgende aspecten behandelen: Functionaliteit na THP: veranderingen in groot-motorische functie, pijn en bewegingsamplitudo;Veranderingen in spierkracht, kinematica van het gaan, gewrichtsmomenten en heupbelasting in subjecten voor en na THP;Het effect van subject-specifieke modellering van de heupgeometrie op de heupbelasting;Het effect van subject-specifieke modellering van heupgeometrie met inbegrip van het heupcentrum, en subject-specifieke gangkarakteristieken op de heupbelasting. Een eerste deelstudie documenteert de veranderingen in groot-motorische functie na THP door middel van de Harris Hip Score (HHS). Dit is een gevalideerd scoresysteem dat de functionele veranderingen kwantificeert na THP. De interafhankelijkheid van pijn, groot-motorische functie, en bewegingsamplitudo werd bestudeerd bij een groep jonge patienten behandeld met een ongecementeerde, op maat gemaakte THP. 79 patienten (< 60, gemiddelde leeftijd 46.2 jaar) werden bestudeerd over een periode van vijf jaar. De totale HHS en de subscores (pijn, groot-motorische functie, bewegingsamplitudo, aanwezigheid van anatomische vervormingen) werden geanalyseerd voor de ingreep en op vier verschillende momenten na de ingreep. Daarnaast werd de interafhankelijkheid tussen de scores, body mass index (BMI), leeftijd en primaire diagnose nagegaan. De resultaten toonden een positieve evolutie na THP, met een tijdsafhankelijke verbetering in pijn, groot-motorische functie en bewegingsamplitudo. Vermindering van pijn werd gerapporteerd in de eerste twee maanden. Daarna werd een verbetering in groot-motorische functie werd vastgesteld, alsook een verdere verbetering in pijn en bewegingsamplitudo. Patienten met congenitale heupdysplasie hadden lagere HHS en een geringere stijging van de HHS over vijf jaar. Na een initiele verbetering in pijnscore werd een significante verbetering in groot-motorische functie van twee maand tot vijf jaar na THP vastgesteld. De primaire diagnose had een significante invloed op de scores tussen één en vijf jaar na de ingreep. Deze resultaten benadrukken het belang van een zorgvuldige timing van de evaluatiemomenten voor het meten van veranderingen in groot-motorische functie na THP. Uitgaande van de resultaten van deze eerste deelstudie werd het tijdsstip voor het meten van veranderingen in gangkarakteristieken na THP vastgelegd op zes weken na de ingreep. Op dat moment is de pijn in grote mate verminderd en werd verbetering in groot-motorische functie vastgesteld. In een tweede deelstudie werden de veranderingen in spierkracht, kinematica van het gaan, gewrichtsmomenten en heupbelasting, evenals de relatie tussen deze parameters geanalyseerd bij 20 patienten en dit net voor en zes weken na THP. De resultaten van deze studie toonden een daling in spierkracht van de heupflexoren en abductoren en geassocieerde veranderingen in gangkinematica en -kinetica aan de aangedane zijde, zes weken na THP. Op vlak van kinematica in het frontale en het sagittale vlak kwamen volgende veranderingen voor:een verminderde heupextensie geassocieerd met een toegenomen bekkenkanteling op het moment van afstoot;een toename in heupadductie tijdens de tweede dubbele steun;een continue bekken hoogstand en toegenomen heupexorotatie. Daarnaast werd een toename in heupflexiemoment tijdens de tweede dubbele steun en powergeneratie tijdens de initiële zwaaifase vastgesteld. Deze afwijkingen in het gangpatroon beïnvloedden de belastingsconfiguratie ter hoogte van het heupgewricht. Meer specifiek werd een daling in de totale contactkracht en zijn verticale component en ook een daling in de geassocieerde inclinatiehoeken van de totale contactkracht in sagittale en transverse vlak vastgesteld, wat duidt op een meer verticale oriëntatie van de implantaatbelasting. Een verminderde verticale oriëntatie van de implantaatbelasting was gerelateerd met excessieve bekkenscheefstand en geassocieerde heupadductie. Uitgaande van deze bevindingen kunnen we suggereren dat de kinesitherapie in de vroege post-operatieve fase in eerste instantie moet focussen op het versterken van de heupflexoren en -abductoren en het stretchen van de anterieure en mediale structuren met als doel het normaliseren van heup- en bekkenkinematica en bijgevolg ook de heupbelasting te normaliseren.In deze studie werd gebruik gemaakt van een generisch model, zonder implementatie van subject-specifieke geometrie. Bijgevolg zijn de geobserveerde veranderingen in heupbelasting het resultaat van de subject-specifieke veranderingen in kinematica en kinetica zes weken na de ingreep. De derde deelstudie behandelt het effect van subject-specifieke modellering van de heupgeometrie op de berekende spieractivatiepatronen en heupcontactkrachten tijdens gaan, gebruik makend van musculoskeletale modellering, inverse dynamische analyses en statische optimalisatie. Eerst werd door middel van een sensitiviteitsanalyse het effect nagegaan van geïsoleerde veranderingen in femorale neklengte (NL) en nek-schacht hoek (NSH) op de berekende spieractivatiepatronen en heupcontactkrachten tijdens de steunfase van het gaan. Een vervormbaar generisch musculoskeletaal model werd stapsgewijs aangepast volgens een fysiologische variatie van NL en NSH. In een tweede gelijkaardige analyse werd de heupgeometrie, gemeten op gedigitaliseerde radiografieën van 20 subjecten met primaire heuposteoarthrose, geïmplementeerd in het model. Ook werd het effect van heupabductorzwakte op spieractivatiepatronen en heupcontactkracht bestudeerd. Deze analyse toont dat verschillen in NL (41 mm 74 mm) en NSH ( 113&deg; - 140&deg;) een effect hebben op de spieractivatie van de heupabductoren in de steunfase en bijgevolg op de heupcontactkracht, met verschillen tot drie keer lichaamsgewicht tot gevolg. Bijgevolg kunnen we concluderen dat de resultaten van zowel de sensitiviteitsanalyse als de subject-specifieke analyse aantonen dat, op het moment van maximale contactkracht, een stijging in NL resulteert in een stijging van de drie componenten van de heupcontactkrachte en een verminderde verticale orientatie van de heupbelasting. Veranderingen in NSH hebben slechts een gering effect op de configuratie van de heupbelasting. In de vierde en laatste deelstudie werd het gecombineerde effect nagegaan van subject-specifieke modellering van de heupanatomie (NL, NSH en femorale anteversie), met inbegrip van de locatie van het heupcentrum (HC), samen met de subject-specifieke gangkarakteristieken op de kwantificatie van heupmomenten, spiermomenten en heupcontactkrachten tijdens gaan. Hiervoor werd gebruik gemaakt van musculoskeletaal modelleren, inverse dynamische analyse en statische optimalisatie. Voor tien subjecten met heupostearthrose werden de heupmomenten, de spiermomenten en de heupbelasting in termen van grootte en oriëntatie berekend, gebruik makend van drie verschillende modeltypes. In elk modeltype werd een verschillende graad van subject-specifiek geometrie geïmplementeerd: (1) een generisch herschaald musculoskeletaal model, (2) een generisch herschaald musculoskeletaal model met subject-specifieke heupanatomie, (3) een generisch herschaald musculoskeletaal model met subject-specifieke heupanatomie met inbegrip van een subject-specifieke locatie van het HC. De subject-specifieke anatomie en het HC werden bepaald aan de hand van CT-beelden. Er werden significante verschillen gevonden tussen de drie modeltypes in HC locatie, heupflexie-extensie moment, medio-laterale contactkracht en inclinatie hoek van de totale contactkracht in het frontale vlak. Uitgaande van deze resultaten kunnen we suggereren dat de CT-gebaseerde musculoskeletale modellen met geïndividualiseerde heupgeometrie met inbegrip van HC locatie gebruikt dienen te worden voor de accurate berekening van heupbelasting. Modellen met minder subject-specifiek detail geven aanleiding tot een substantiële onderschatting van de heupcontactkracht van de patiënt en tot foutieve conclusies met betrekking tot de geassocieerde oriëntatie van de kracht. Op basis van deze resultaten werd geconcludeerd dat gepersonaliseerde musculoskeletale modellen met inbegrip van subject-specifieke heup geometrie, HC locatie en gangkarakteristieken, essentieel zijn voor een accurate berekening van de heupbelasting.Table of Contents Acknowledgements i Table of Contents 1 Abstract (English) 5 Samenvatting (Nederlands) 9 Chapter 1: Methodology and rationale for quantifying hip joint loading 13 Introduction 13 Methodology 14 Overview 14 Musculoskeletal modelling 14 Gait analysis 15 Inverse dynamics 16 0ptimization 16 Objectives and hypotheses 17 Overview 17 Evaluating THR outcome 17 Influence of changed kinetics and kinematics on hip loading 18 Influence of musculoskeletal geometry on hip joint loading 19 Subject-specific modelling of hip anatomy 21 References 22 Chapter 2: Functional outcome after cementless, custom-made total hip replacement in patients younger than 60: A 5-year follow-up 27 Abstract 27 Introduction 27 Methods 29 Results 31 Harris Hip Score 31 HHS Sub Scores 32 Factors influencing HHS 33 Discussion 34 Acknowledgements 38 References 38 Chapter 3: Changes in kinematics, kinetics and hip contact forces during gait before and six weeks after total hip replacement 41 Abstract 41 Introduction 41 Methods 43 Subjects 43 Gait analysis 43 Musculoskeletal modelling 44 Statistics 44 Results 46 Maximal Voluntary Contraction (MVC) 46 Spatio-temporal parameters 46 Kinematics 46 Kinetics 48 Contact forces 48 Relation between muscle force generating capacity, kinematics, kinetics and contact forces 48 Discussion 51 Acknowledgements 54 References 55 Chapter 4: Subject-specific hip geometry affects predicted hip joint contact forces during gait 59 Abstract 59 Introduction 59 Methods 61 Subjects 61 Biomechanical analysis 62 Sensitivity analysis 64 Subject-specific modelling 66 Statistical analysis 66 Results 66 Effect of the neck-shaft angle (NSA) on muscle activity distribution 66 Effect of neck-length (NL) on muscle activity distribution 68 Effect of neck-shaft angle (NSA) on peak hip contact forces 68 Effect of neck-length (NL) on peak hip contact forces 69 Results of the statistical analysis 70 Effect of halved abductor force generating capacity 70 Discussion 70 Acknowledgements 74 References 74 Chapter 5: Modelling subject-specific hip geometry and hip joint centre location affects joint moments, muscle moment generating capacity and contact forces at the hip during gait 77 Abstract 77 Introduction 77 Methods 79 Subjects 79 Measurement of subject-specific geometry and HJC location 79 Gait analysis 79 Musculoskeletal modelling 80 Data analysis and statistics 82 Results 84 Discussion 86 Acknowledgements 89 References 89 Chapter 6: Conclusions 91 Overview 91 Evaluating THR outcome 91 Influence of changed kinetics and kinematics on hip loading 92 Influence of musculoskeletal geometry on hip joint loading 93 Subject-specific modelling of hip geometry 95 Limitations of this research 96 General conclusion 98 Suggestions for future research 101 References 103 Appendix I: Relation among subject-specific hip joint loading, stress distribution in the proximal femur and bone mineral density changes after total hip replacement 107 Abstract 107 Introduction 107 Methods 108 Finite element models 109 Calculation of muscle forces and hip contact forces using gait analysis and musculoskeletal modelling 109 Calculation of bone stress using finite element analysis 110 BMD measurements 112 Results 113 Changes in bone stresses before and after THR 113 Effect of altered loading conditions on bone stresses 115 Correlation with BMD 116 Discussion 117 Acknowledgements 119 References 119 Appendix II: Bijstellingen 123 Bijstelling 1 123 Bijstelling 2 123 Bijstelling 3 123 Appendix III: Professional Career Gerlinde Lenaerts 125 Biography 125 Current publication list 125 Papers in peer reviewed Journals 125 Published conference abstracts 126 Appendix IV: Author affiliations 129 Corresponding author 129 Co-authors 129 Appendix V: Abbreviations 131status: publishe

Tools to assess the trustworthiness of evidence-based point-of-care information for health care professionals: A systematic review

BACKGROUND: User-friendly information at the point of care should be well structured, rapidly accessible, and comprehensive. Also, this information should be trustworthy, as it will be used by health care practitioners to practice evidence-based medicine. Therefore, a standard, validated tool to evaluate the trustworthiness of such point-of-care information resources is needed. OBJECTIVE: This systematic review sought to search for tools to assess the trustworthiness of point-of-care resources and to describe and analyze the content of these tools. METHODS: A systematic search was performed on three sources: (1) we searched online for initiatives that worked off of the trustworthiness of medical information; (2) we searched Medline (PubMed) until June 2019 for relevant literature; and (3) we scanned reference lists and lists of citing papers via Web of Science for each retrieved paper. We included all studies, reports, websites, or methodologies that reported on tools that assessed the trustworthiness of medical information for professionals. From the selected studies, we extracted information on the general characteristics of the tools. As no standard, risk-of-bias assessment instruments are available for these types of studies, we described how each tool was developed, including any assessments on reliability and validity. We analyzed the criteria used in the different tools and divided them into five categories: (1) author-related information; (2) evidence-based methodology; (3) website quality; (4) website design and usability; and (5) website interactivity. The percentage of tools in compliance with these categories and the different criteria were calculated. RESULTS: Included in this review was a total of 17 tools, all published between 1997 and 2018. The tools were developed for different purposes, from a general quality assessment of medical information to very detailed analyses, all specifically for point-of-care resources. However, the development process of the tools was poorly described. Overall, seven tools had a scoring system implemented, two were assessed for reliability only, and two other tools were assessed for both validity and reliability. The content analysis showed that all the tools assessed criteria related to an evidence-based methodology: 82% of the tools assessed author-related information, 71% assessed criteria related to website quality, 71% assessed criteria related to website design and usability, and 47% of the tools assessed criteria related to website interactivity. There was significant variability in criteria used, as some were very detailed while others were more broadly defined. CONCLUSIONS: The 17 included tools encompass a variety of items important for the assessment of the trustworthiness of point-of-care information. Overall, two tools were assessed for both reliability and validity, but they lacked some essential criteria for the assessment of the trustworthiness of medical information for use at the point-of-care. Currently, a standard, validated tool does not exist. The results of this review may contribute to the development of such an instrument, which may enhance the quality of point-of-care information in the long term. TRIAL REGISTRATION: PROSPERO CRD42019122565; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=122565.status: accepte

How Pathological Gait Kinematics, Increased Femoral Anteversion and Neck Shaft Angle Adversely Affect the Loading Conditions of the Femoral Head During Gait in Children With Cerebral Palsy

status: publishe

Accuracy assessment of surgical planning and three-dimensional-printed patient-specific guides for orthopaedic osteotomies

This study analyses the accuracy of three-dimensional pre-operative planning and patient-specific guides for orthopaedic osteotomies. To this end, patient-specific guides were compared to the classical freehand method in an experimental setup with saw bones in two phases. In the first phase, the effect of guide design and oscillating versus reciprocating saws was analysed. The difference between target and performed cuts was quantified by the average distance deviation and average angular deviations in the sagittal and coronal planes for the different osteotomies. The results indicated that for one model osteotomy, the use of guides resulted in a more accurate cut when compared to the freehand technique. Reciprocating saws and slot guides improved accuracy in all planes, while oscillating saws and open guides lead to larger deviations from the planned cut. In the second phase, the accuracy of transfer of the planning to the surgical field with slot guides and a reciprocating saw was assessed and compared to the classical planning and freehand cutting method. The pre-operative plan was transferred with high accuracy. Three-dimensional-printed patient-specific guides improve the accuracy of osteotomies and bony resections in an experimental setup compared to conventional freehand methods. The improved accuracy is related to (1) a detailed and qualitative pre-operative plan and (2) an accurate transfer of the planning to the operation room with patient-specific guides by an accurate guidance of the surgical tools to perform the desired cuts

Subject-specific musculoskeletal models are needed to predict the influence of hip replacement on hip contact force

status: publishe

A Tool to Assess the Trustworthiness of Evidence-Based Point-of-Care Information for Health Care Professionals (CAPOCI): Design and Validation Study

BackgroundUser-friendly information at the point of care for health care professionals should be well structured, rapidly accessible, comprehensive, and trustworthy. The reliability of information and the associated methodological process must be clear. There is no standard tool to evaluate the trustworthiness of such point-of-care (POC) information. ObjectiveWe aim to develop and validate a new tool for assessment of trustworthiness of evidence-based POC resources to enhance the quality of POC resources and facilitate evidence-based practice. MethodsWe designed the Critical Appraisal of Point-of-Care Information (CAPOCI) tool based on the criteria important for assessment of trustworthiness of POC information, reported in a previously published review. A group of health care professionals and methodologists (the authors of this paper) defined criteria for the CAPOCI tool in an iterative process of discussion and pilot testing until consensus was reached. In the next step, all criteria were subject to content validation with a Delphi study. We invited an international panel of 10 experts to rate their agreement with the relevance and wording of the criteria and to give feedback. Consensus was reached when 70% of the experts agreed. When no consensus was reached, we reformulated the criteria based on the experts’ comments for a next round of the Delphi study. This process was repeated until consensus was reached for each criterion. In a last step, the interrater reliability of the CAPOCI tool was calculated with a 2-tailed Kendall tau correlation coefficient to quantify the agreement between 2 users who piloted the CAPOCI tool on 5 POC resources. Two scoring systems were tested: a 3-point ordinal scale and a 7-point Likert scale. ResultsAfter validation, the CAPOCI tool was designed with 11 criteria that focused on methodological quality and author-related information. The criteria assess authorship, literature search, use of preappraised evidence, critical appraisal of evidence, expert opinions, peer review, timeliness and updating, conflict of interest, and commercial support. Interrater agreement showed substantial agreement between 2 users for scoring with the 3-point ordinal scale (τ=.621, P<.01) and scoring with the 7-point Likert scale (τ=.677, P<.01). ConclusionsThe CAPOCI tool may support validation teams in the assessment of trustworthiness of POC resources. It may also provide guidance for producers of POC resources