A biomechanical investigation of seated balance and upright mobility with a robotic exoskeleton in individuals with a spinal cord injury

Spinal cord injury (SCI) is a complex medical condition with multiple sequelae. The level and severity of a lesion will determine the degree of disability and associated co- morbidities, the most obvious of which is paralysis. Other concomitant issues, such as muscle contractures, poor seated posture and fear of falling, can also lead to a reduced quality of life. Although there is currently no cure for SCI, many of the comorbidities can be managed or mitigated through technology and physical rehabilitation practices.The aim of this thesis was to inform spinal cord injury (SCI) mobility rehabilitation, focusing on postural control and upright stepping using robotic assisted gait training (RAGT). A systematic review investigating RAGT use in SCI concluded that although RAGT has the potential to benefit upright locomotion of SCI individuals, it should not replace other therapies but should be incorporated into a multi-modality rehabilitation approach.Seated postural control, upper-body posture and fear-of-falling in SCI individuals were also explored. Stability performance and control demand were compared between high- and low-level injury groups as was fear-of-falling. An individualised limit of stability boundary (LOS) facilitated the differentiation between high- and low-level injuries during static tasks; however, its use during dynamic tasks was limited and potentially influenced by fear-of-falling.Few studies have quantified the user’s motion inside a lower limb robotic exoskeleton (LEXO), and none have reported marker placement repeatability. Standard error of measurement was reported for three-dimensional trunk and pelvic orientations and hip, knee and ankle angles in the sagittal plane during level walking. This revealed the marker set and placement to produce good levels of agreement between visits, with most values falling between the accepted standard of 2-5o. These findings indicated that the marker placement was repeatable and could be used in the subsequent chapters involving motion capture of overground walking.Three-dimensional gait parameters of able-bodied individuals walking with and without a LEXO at two speeds (comfortable (CMBL) and speed-matched (SLOW) to the LEXO) were investigated. Statistical parametric mapping revealed significantly different waveforms at the ANOVA level for all kinematic variables, however minimal differences in sagittal plane lower limb kinematics were identified between LEXO and SLOW gait, suggesting LEXO gait resembled slow walking when speed-matched. Altered kinematics of the pelvis and trunk during LEXO use suggest that overground exoskeletons may provide a training environment benefiting postural control training.Finally, the biomechanical characteristics of able-bodied and SCI users walking in an overground LEXO were investigated. Variables associated with neuroplasticity in SCI (hip extension and lower limb un-loading) were not significantly different between groups, indicating that afferent stimuli to facilitate neuroplastic adaptations in individuals with a SCI can be generated during LEXO gait. Upper-body orientation facilitated stepping and maintained balance, thereby requiring the participant’s active involvement.This thesis has provided evidence that LEXOs can deliver appropriate stimuli for upright stepping and that upper-body engagement can facilitate postural control training, potentially leading to improved seated postural control

Aerospace medicine and biology: A cumulative index to a continuing bibliography (supplement 358)

This publication is a cumulative index to the abstracts contained in Supplements 346 through 357 of Aerospace Medicine and Biology: A Continuing Bibliography. It includes seven indexes: subject, personal author, corporate source, foreign technology, contract number, report number and accession number

Bio-Inspired Soft Artificial Muscles for Robotic and Healthcare Applications

Soft robotics and soft artificial muscles have emerged as prolific research areas and have gained substantial traction over the last two decades. There is a large paradigm shift of research interests in soft artificial muscles for robotic and medical applications due to their soft, flexible and compliant characteristics compared to rigid actuators. Soft artificial muscles provide safe human-machine interaction, thus promoting their implementation in medical fields such as wearable assistive devices, haptic devices, soft surgical instruments and cardiac compression devices. Depending on the structure and material composition, soft artificial muscles can be controlled with various excitation sources, including electricity, magnetic fields, temperature and pressure. Pressure-driven artificial muscles are among the most popular soft actuators due to their fast response, high exertion force and energy efficiency. Although significant progress has been made, challenges remain for a new type of artificial muscle that is easy to manufacture, flexible, multifunctional and has a high length-to-diameter ratio. Inspired by human muscles, this thesis proposes a soft, scalable, flexible, multifunctional, responsive, and high aspect ratio hydraulic filament artificial muscle (HFAM) for robotic and medical applications. The HFAM consists of a silicone tube inserted inside a coil spring, which expands longitudinally when receiving positive hydraulic pressure. This simple fabrication method enables low-cost and mass production of a wide range of product sizes and materials. This thesis investigates the characteristics of the proposed HFAM and two implementations, as a wearable soft robotic glove to aid in grasping objects, and as a smart surgical suture for perforation closure. Multiple HFAMs are also combined by twisting and braiding techniques to enhance their performance. In addition, smart textiles are created from HFAMs using traditional knitting and weaving techniques for shape-programmable structures, shape-morphing soft robots and smart compression devices for massage therapy. Finally, a proof-of-concept robotic cardiac compression device is developed by arranging HFAMs in a special configuration to assist in heart failure treatment. Overall this fundamental work contributes to the development of soft artificial muscle technologies and paves the way for future comprehensive studies to develop HFAMs for specific medical and robotic requirements

Soluções em fibra ótica para sistemas de reabilitação física e aplicações e-Health

In this dissertation a biaxial optical fiber sensor, based on Bragg gratings, is proposed for simultaneous monitoring of plantar and shear pressures. This work begins with the definition of the problem: the consequences of pathologies associated with diabetic foot and lower limbs disorders. It was analysed several previously published studies on plantar pressure sensors, the several methodologies and applications that already exist. A biomechanical research was carried out, with particular focus on gait pattern and human foot anatomy, in order to understand the different gait phases and points of greatest interest for foot pressure monitoring. Thus, the response of sensors based on Bragg gratings was studied in several configurations of sensing cells, then integrated in insoles. The sensitivities obtained for normal pressure were between 0.56 and 2.16 pm/kPa and, for shear pressure, between 0.51 and 3.98 pm/kPa. Those prove to be a non-invasive solution with potential to be included in e-health systems for real-time gait monitoring. They can be prepared for daily medical use, serving as important tools in aiding prevention and diagnosis, especially of foot diseases.Nesta dissertação é proposto um sensor biaxial em fibra ótica, baseado em redes de Bragg, para monitorização simultânea de pressões plantar e de cisalhamento. Este trabalho começa com a definição do problema: as consequências de patologias associadas ao pé diabético e distúrbios na sincronização dos membros inferiores. Foram analisados vários estudos publicados anteriormente sobre sensores de pressão plantar, as diversas metodologias e aplicações já existentes. Foi realizada uma pesquisa na área da biomecânica, com particular foco no padrão de marcha e na anatomia do pé humano, de forma a compreender as diferentes fases da marcha e os pontos de maior interesse para monitorização da pressão do pé. Assim, foi desenvolvido um estudo sobre a resposta de sensores baseados em redes de Bragg à pressão, em várias configurações de células sensoriais, culminando na integração desses sensores em palmilhas. Foram obtidas sensibilidades para pressão normal entre 0,56 e 2,16 pm/kPa e, para pressão de cisalhamento, entre 0,51 e 3,98 pm/kPa. Estas demonstram ser uma solução não invasiva, com potencial de ser incluída em sistemas e-Health, para monitorização da marcha em tempo real. Podem ser preparadas para uso médico diário, servindo como importantes ferramentas no auxílio para a prevenção e diagnóstico, em especial de doenças do pé.Mestrado em Engenharia Físic

Exploration of peripheral electrical stimulation adapted as a modulation tool for reciprocal inhibition through the activation of afferent fibers during gait

The most accessible manner to perform physical activity and allow locomotion in human beings is walking. This activity is allowed thanks to reciprocal Ia inhibition mechanism, controlled by the spinal and supraspinal inhibitory circuits. The idea of this mechanism is to deactivate the antagonist muscle while the agonist is being contracted, allowing the proper muscle coordination necessary to walk. The interruption of spinal fibers produced after Spinal Cord Injury, disrupt this control on reciprocal Ia inhibition. The result of this lack of control is a co-activation of antagonist muscles generating spasticity of lower limbs which induce walking impairments. The importance of walking recovery for the independence and society re-integration of patient, raise the quantity of emerging walking rehabilitation therapies. One of these therapies, the application of peripheral nerve stimulation, has demonstrated promising results although more studies are necessary. This theory is the base of this Master Thesis which aim is to develop and validate a gait neuromodu- lation platform that induce neuroplasticity of spinal circuits, improving reciprocal Ia inhibition. The idea of the platform is to deliver afferent stimulation into the Common Peroneal Nerve innervating Tibialis Anterior muscle, to induce reciprocal Ia inhibition onto the antagonist Soleus muscle. This platform has been validated in 20 healthy volunteers in order to assess its effectiveness. The first part of the experimental protocol is an off-line analysis of Gait Cycle to evaluate the activation of mus- cles during the different phases of this cycle. Then, there is an assessment of the activity of antagonist muscle previous to the stimulation intervention by using the analysis of soleus H-reflex. Posteri- orly, the afferent stimulation is applied during a 10 minutes treadmill training using three different strategies depending on patient: In-phase stimulation during swing phase, Out-of-phase stimulation during stance phase, and Control strategy to check if stimulation has a real effect. The final processes of experimental protocol are two different assessments of the soleus activity, one immediately after the intervention and other 30 minutes after to evaluate the duration of effects. The results obtained demonstrate that afferent electrical stimulation has a real effect on modulation of reciprocal Ia inhibition. On the one hand, when electrical stimulation is applied during the swing phase, there is an improvement of reciprocal Ia inhibition. On the other hand, when stimulation is delivered during the stance phase, there is a worsening of reciprocal Ia inhibition. These results conclude that afferent electrical stimulation, applied at the swing phase of gait cycle, is a promising strategy to induce reciprocal Ia inhibition in Spinal Cord Injury patients. The induc- tion of this inhibitory circuit will lead to the proper activation of muscles during walking, recovering impaired walkingLa forma más accesible de locomoción y actividad física en los seres humanos es caminar. Esta activi- dad se realiza gracias al mecanismo de inhibición recíproca, controlado por los circuitos inhibitorios espinales y supraespinales. La idea de este mecanismo es desactivar el músculo antagonista mientras se contrae el agonista, permitiendo la adecuada coordinación muscular durante la marcha. La interrupción de las fibras espinales tras una Lesión de la Médula Espinal desajusta el control de la inhibition reciprocal. El resultado de esta falta de control es una co-activación de los músculos antago- nistas generando espasticidad en las extremidades inferiores, lo que genera alteraciones en la marcha. La importancia de la recuperación de la marcha para lograr la independencia y la reintegración del paciente en la sociedad, ha incrementado el número de terapias emergentes en rehabilitación de la marcha. Una de estas terapias, la estimulación del nervio periférico, ha demostrado resultados prom- etedores. Esta teoría es la base de esta Tesis de Máster cuyo objetivo es desarrollar y validar una plataforma de neuromodulación de la marcha que induzca la neuroplasticidad de los circuitos espinales, mejorando los valores de inhibición recíproca. La idea es aplicar estimulación aferente en el Nervio Peroneo Común que inerva el músculo Tibial Anterior para inducir la inhibición recíproca en su músculo antagonista Soleo. Esta plataforma ha sido validada en 20 voluntarios sanos con el fin de evaluar su eficacia. La primera parte del protocolo experimental es un análisis del ciclo de la marcha para evaluar la activación de cada músculo durante las diferentes fases de este ciclo. Luego, previo a la intervención de estimu- lación, hay una evaluación de la actividad del músculo antagonista analizando el reflejo H del soleo. La intervención de estimulación aferente se aplica durante un entrenamiento de marcha con una du- ración de 10 minutos, utilizando tres estrategias diferentes dependiendo del paciente: estimulación ’In-phase’ durante la fase de oscilación, estimulación ’Out-of-phase’ durante la fase de postura, y ’Control’ para comprobar si la estimulación tiene un efecto real. Los procesos finales del protocolo son dos evaluaciones de la actividad del soleo, una inmediatamente después de la intervención y otra 30 minutos después para evaluar la duración de los efectos. Los resultados obtenidos demuestran que la estimulación eléctrica aferente tiene un efecto real en la modulación de la inhibición recíproca. Por un lado, cuando la estimulación eléctrica se aplica durante la fase de oscilación, hay una mejora de la inhibición recíproca. Por otro lado, cuando la estimulación se administra durante la fase de postura, hay un empeoramiento de la inhibición recíproca. Estos resultados concluyen que la estimulación eléctrica aferente, administrada en la fase de oscilación del ciclo de la marcha, es una estrategia prometedora para inducir la inhibición recíproca en pacientes con Lesión de la Médula Espinal. La inducción de este circuito inhibidor generará la adecuada acti- vación de los músculos durante la marcha, recuperando el ciclo de marcha normalLa manera més accessible de locomoció i activitat física en els éssers humans és caminar. Aquesta ac- tivitat es realitza gràcies al mecanisme d’inhibició recíproca, controlat pels circuits inhibitoris espinals i supraespinals. La idea d’aquest mecanisme és desactivar el múscul antagonista mentre es contrau l’agonista, permetent la coordinació muscular adequada durant la marxa. La interrupció de les fibres espinals després d’una lesió medul·lar desajusta el control de la inhibició reciprocal. El resultat d’aquesta manca de control és una coactivació dels músculs antagonistes gen- erant espasticitat a les extremitats inferiors, cosa que genera alteracions a la marxa. La importància de la recuperació de la marxa per a la independència i la reintegració del pacient a la societat, ha incrementat el nombre de teràpies emergents de rehabilitació de la marxa. Una daquestes teràpies, lestimulació del nervi perifèric, ha demostrat resultats prometedors. Aquesta teoria és la base dáquesta Tesi de Màster que té com a objectiu desenvolupar una plataforma de neuromodulació de la marxa que indueixi la neuroplasticitat dels circuits espinals, millorant els valors de inhibició recíproca. La idea és aplicar una estimulació aferent al Nervi Peroneal Comú que inerva el múscul Tibial Anterior per induir la inhibició recíproca al múscul antagonista Soli. Aquesta plataforma ha estat validada en 20 voluntaris sans per avaluar-ne l’eficàcia. La primera part del protocol experimental és una anàlisi del cicle de marxa per avaluar l’activació de cada múscul durant les diferents fases del cicle de la marxa. Després, amb la intervenció d’estimulació prèvia, hi ha una avaluació de l’activitat del múscul antagonista analitzant el reflex H del soli. La inter- venció d’estimulació aferent s’aplica durant un entrenament de marxa amb una durada de 10 min- uts, utilitzant tres estratègies diferents depenent del pacient: estimulació ’In-phase’ durant la fase d’oscil·lació, estimulació ’Out-of-phase’ durant la fase de postura, i ’Control’ per comprovar si la es- timulació té un efecte real. Els processos finals del protocol són dues avaluacions de l’activitat de soli, una immediatament després de la intervenció i una altra 30 minuts després per avaluar la durada dels efectes. Els resultats obtinguts demostren que l’estimulació elèctrica aferent té un efecte real en la modulació de la inhibició recíproca. D’una banda, quan s’aplica l’estimulació elèctrica durant la fase d’oscil·lació, hi ha una millora de la inhibició recíproca. D’altra banda, quan s’administra l’estimulació durant la fase de postura, hi ha un empitjorament de la inhibició recíproca. Aquests resultats conclouen que l’estimulació elèctrica aferent, a la fase d’oscil·lació del cicle de la marxa, és una estratègia prometedora per induir la inhibició recíproca en pacients amb lesió medul·lar. La inducció d’aquest circuit inhibidor generarà a l’activació adequada dels músculs durant la marxa, recuperant el cicle de marxa norma

Evidence Synthesis of Shoulder Pain Among Canadian Firefighters

Injury or degeneration of rotator cuff tendon leads to rotator cuff disease (subacromial impingement syndrome and rotator cuff tears). Shoulder pain – pain in the upper arm close to the deltoid muscle insertion has been reported as the most common symptom for subacromial impingement syndrome and rotator cuff tears. However, the current state of evidence on treatment effectiveness of rotator cuff disease is indeterminate. The shoulder function is essential for many of the physically demanding tasks that firefighters perform on the fire ground. For fire services and firefighters, the preservation of active duty is critical for their continued service to their communities. However, the prevalence of shoulder pain among Canadian firefighters has not been synthesized. Further, high quality randomized clinical trials (RCTs) provide the highest level of evidence and assist in clinical decision making. The International Committee of Medical Journal Editors (ICMJE) recommendation of RCT trial registration in public trials registry has been made to improve the reporting, transparency, rigor and reproducibility in RCTs. However, there is a paucity of evidence on the proportion of RCTs with proper trial registrations in the field of rehabilitation therapy. Therefore, the purposes of this thesis were 1) to assess the effects of arthroscopic versus mini-open rotator cuff repair surgery on function, pain and range of motion at in patients with rotator cuff tears; 2) to quantify the effects of surgical vs conservative interventions on clinical outcomes of pain and function in patients with subacromial impingement syndrome; 3) to assess the prevalence of musculoskeletal disorders (MSDs) among Canadian firefighters, 4) to examine the proportion of RCTs that were reported to have been prospectively, retrospectively registered or not registered in the field of rehabilitation therapy, and 5) to use the synthesized evidence to inform the design of a single center (fire-station), investigator-blinded, randomized, 12-month, parallel-group, superiority trial for the evaluation of the efficacy of a shoulder exercises on clinical outcomes in firefighters with shoulder pain. From the existing literature, we found evidence that both arthroscopic and mini-open techniques to rotator cuff repairs with post-operative rehabilitation exercises were effective in improving clinical outcomes of function, pain and shoulder range of motion in patients with rotator cuff tears. However, the between-group differences in outcomes were too small to be clinically important. The effects of surgery plus physiotherapy (exercises) vs physiotherapy (exercises) alone on pain and function were too small to be clinically important at 3-, 6-months, 1-, 2-, 5- and ≥ 10-years follow up. This further highlighted that rehabilitation exercises be considered as the first treatment approach in patients with shoulder pain. We also identified high point-prevalence estimates (1 in 4 firefighters) of shoulder-, back-, and knee-related MSDs among Canadian firefighters (shoulder pain was 23%). Our review study indicated that fifteen years after the introduction of standards for RCT registration by ICMJE, only one-third of the RCTs in the field of rehabilitation therapy were prospectively registered. Subsequently, the emergence of further evidence (observational studies in firefighters and RCTs in active-duty military personnel) indicating the clinical effectiveness of occupation-specific rehabilitation exercises along with our evidence syntheses provided the rationale for the design and conduct of an RCT to assess the effectiveness of firefighter-specific rehabilitation exercises among Canadian firefighter with shoulder pain

Book of Abstracts 15th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering and 3rd Conference on Imaging and Visualization

In this edition, the two events will run together as a single conference, highlighting the strong connection with the Taylor & Francis journals: Computer Methods in Biomechanics and Biomedical Engineering (John Middleton and Christopher Jacobs, Eds.) and Computer Methods in Biomechanics and Biomedical Engineering: Imaging and Visualization (JoãoManuel R.S. Tavares, Ed.). The conference has become a major international meeting on computational biomechanics, imaging andvisualization. In this edition, the main program includes 212 presentations. In addition, sixteen renowned researchers will give plenary keynotes, addressing current challenges in computational biomechanics and biomedical imaging. In Lisbon, for the first time, a session dedicated to award the winner of the Best Paper in CMBBE Journal will take place. We believe that CMBBE2018 will have a strong impact on the development of computational biomechanics and biomedical imaging and visualization, identifying emerging areas of research and promoting the collaboration and networking between participants. This impact is evidenced through the well-known research groups, commercial companies and scientific organizations, who continue to support and sponsor the CMBBE meeting series. In fact, the conference is enriched with five workshops on specific scientific topics and commercial software.info:eu-repo/semantics/draf

Neurogenic Bowel Dysfunction

Disorders of the central and peripheral nerve systems have severe effects on gut function. Hence, people who have sustained spinal cord injury and multiple sclerosis, Parkinson’s disease, or spina bifida patients may suffer from severe bowel symptoms, including constipation, incontinence to stools, difficult bowel evacuation, or pain. For the present book, a number of international experts have described how disorders of the nerve system affect bowel function, how to assess and treat bowel symptoms, and how the bacterial composition of the bowel may be affected

Hip deformities and femoroacetabular impingement

RESUMO: Conceptualmente, a conservação de uma estrutura anatómica é mais benéfica do que a sua substituição. No caso das articulações humanas, este conceito é particularmente importante face aos múltiplos problemas, ainda não resolvidos, relacionados com próteses e materiais usados na cirurgia ortopédica. Na articulação coxofemoral, o conceito de preservação, melhorando os parâmetros biomecânicos, assume uma complexidade técnica acrescida maioritariamente pelo facto de a circulação epifisária do fémur ser intra-articular e dada a proximidade de importantes estruturas neurovasculares. O conflito femoroacetabular (CFA) e a displasia acetabular no adulto jovem, são duas entidades patológicas comuns embora com múltiplas áreas ainda por investigar. A displasia infantil, não diagnosticada e não tratada, pode originar displasia acetabular residual na idade adulta e consequente sintomatologia e limitação funcional. O diagnóstico de CFA no adulto é baseado em critérios clínicos e radiográficos. Clinicamente apresenta-se igualmente com dor e limitação funcional. Radiologicamente, dois subtipos de CFA são habitualmente reconhecidos, o tipo Cam (mecanismo patológico decorrente de asfericidade femoral) e o tipo Pincer (por hipercobertura acetabular). Embora com padrões diferentes de envolvimento articular, os dois mecanismos de conflito condicionam dor, lesão estrutural do labrum e condropatia. Atualmente, a morfologia Cam é considerada como um dos principais fatores de risco morfológico que contribuem para o desenvolvimento de osteoartrose precoce da coxofemoral, eventualmente com necessidade de recurso a prótese total da anca. Apesar de a investigação inicial na área da cirurgia conservadora da anca ter documentado bons resultados cirúrgicos, atualmente a controvérsia é francamente superior ao consenso relativamente à melhor abordagem diagnóstica e terapêutica. Caracteristicamente, apesar de em muitos casos os achados clínicos e radiológicos serem inequívocos para o diagnóstico de CFA, um número substancial de doentes apresenta achados frustes ou equívocos. Por outro lado, múltiplos estudos descreveram uma alta prevalência de morfologia compatível com CFA na população adulta e em indivíduos saudáveis assintomáticos. Atualmente, não existe uma ferramenta de imagem ideal que facilite a alocação fidedigna de todos os doentes a um grupo patológico específico ou, por outro lado, exclua com confiança o diagnóstico de conflito. No entanto, os parâmetros de imagem podem ser utilizados para analisar e descrever as diferentes características morfológicas da anca e adicionalmente confirmar o diagnóstico de CFA. Esta tese enfoca, por um lado, a avaliação da morfologia coxofemoral em diferentes populações, investigando quais articulações estão mais predispostas ao desenvolvimento de sintomas e, por outro, os resultados do tratamento cirúrgico de uma coorte com o diagnóstico de CFA tipo Cam. Especificamente, a investigação efetuada: 1) examinou características morfológicas específicas da coxofemoral em diferentes populações (sintomáticas ou não sintomáticas); 2) desenhou um modelo estatístico baseado em preditores anatómicos no sentido de estabelecer as articulações em risco de desenvolvimento sintomático, incorporando geometrias articulares específicas e parâmetros espinhopélvicos; e 3) analisou os resultados de terapêutica cirúrgica numa coorte de doentes com o diagnóstico CFA tipo Cam. Durante a progressão clínica na área da imagiologia e nesta área patológica em particular, apercebemo-nos da existência de múltiplas lacunas de conhecimento que procurámos colmatar com a investigação agora publicada e descrita nesta tese. A sistematização por capítulos reflete precisamente a necessidade de abordar a questão em áreas de conhecimento, simultaneamente distintas e complementares. Os seis capítulos desta tese abrangem o espectro clínico desde o diagnóstico até ao tratamento da anca jovem. De modo a apresentar os objetivos desta tese numa sequência lógica, desde a anatomia geral até à morfologia e tratamento específicos do CFA, a análise da anca assintomática será descrita em primeiro lugar seguida pela análise da relação anatomoclínica entre morfologia articular e sintomas. Por último será abordada a terapêutica do doente sintomático. Na PARTE I, apresentamos os tópicos essenciais para compreender a abrangência do espectro da presente tese, designadamente a relevância e a contemporaneidade do tema “CFA” e adicionalmente o enquadramento anatómico, morfológico e vascular desta articulação. O Capítulo 1 é dedicado ao desenvolvimento e morfogénese da anca. No Capítulo 2, sublinhamos a importância e o papel da imagem através de uma revisão enfocada nas perspetivas atuais e futuras sobre este tópico (Artigo I). No Capítulo 3, realizamos uma revisão sistemática da literatura no sentido de descrever o estado da arte com foco na prevalência da morfologia de CFA em populações assintomáticas e sintomáticas. Este capítulo destaca as múltiplas lacunas de conhecimento relativas ao papel da morfologia da articulação coxofemoral na patogénese do CFA (Artigo II). Com base nesta parte introdutória, abordamos seguidamente os objetivos da presente tese, gerais e específicos, na PARTE II.Na PARTE III, descrevemos o corpo da investigação clínica original efetuada. O Capítulo 4 é dedicado à caracterização detalhada da morfologia da anca, designadamente óssea e vascular. A morfologia coxofemoral foi quantificada utilizando software com capacidade de semi-automatização analítica, permitindo estudar a prevalência e relação entre as diferentes morfologias articulares e o género, dominância e simetria articular (Artigo III). A morfologia Cam foi ainda alvo de caracterização mais aprofundada, através do desenvolvimento de um novo parâmetro quantitativo com potencialidade diagnóstica e de planeamento cirúrgico/ /prognóstico, primariamente testado numa coorte assintomática (Artigo IV) e seguidamente também em doentes com indicação cirúrgica (Artigo V). Na nossa atividade clínica diária apreciámos a necessidade urgente de melhor caracterizar a topografia da deformidade Cam e a respetiva relação com as artérias nutritivas da epífise femoral. A impressão clínica referida sugeria que a morfologia Cam frequentemente se estendia posteriormente ao quadrante póstero-superior, intersectando a região retinacular vascular. No entanto, por imagem a natureza arterial destas estruturas nunca havia sido confirmada. Por esta razão, a importância do parâmetro mencionado foi sublinhada e comprovada no estudo cadavérico com avaliação topográfica vascular do fémur proximal (Artigo VI). No Capítulo 5 testámos múltiplos parâmetros imagiológicos e respetivas variações/relações com diferentes morfologias coxofemorais, no sentido de identificar as articulações com risco clínico aumentado de desenvolvimento sintomático. Para este fim efetuámos estudos baseados em computação avançada com modelação estatística (Artigo VII) e também em ressonância magnética (RM) tridimensional (Artigo VIII). O Capítulo 6 descreve as opções de tratamento (Artigo IX) e os resultados clínicos num estudo clínico de uma coorte com follow-up mínimo de 2 anos, comparando a abordagem cirúrgica aberta e artroscópica (Artigo X). Os resultados dos diferentes capítulos estão sumarizados na PARTE IV, onde apresentamos a síntese geral, a discussão crítica dos resultados obtidos à luz da literatura atual e finalmente as conclusões relevantes. As oportunidades futuras de investigação são igualmente abordadas neste capítulo. Em resumo o trabalho constante da presente tese sugere: Primeiro, que a avaliação imagiológica detalhada da morfologia coxofemoral é essencial no sentido de compreender aprofundadamente não só a própria articulação como também a morfologia pélvica (Artigo I). Segundo, paradoxalmente, a definição clínica de um caso patológico e das diferentes entidades relacionadas, é ainda inexistente. Os parâmetros quantitativos e qualitativos que comummente estão associados com CFA tipo Pincer e Cam são francamente frequentes em diferentes populações (sintomáticas e assintomáticas) (Artigo II).Terceiro, em populações assintomáticas adultas, os intervalos de referência específicos para os parâmetros quantitativos associados a morfologia de CFA e displasia são mais latos e com limites superiores mais elevados do que os atualmente utilizados na prática clínica (Artigo III). A morfologia femoral bem como os epicentros/magnitudes das deformidades Cam são específicos de género, observando-se maiores valores de ângulo alfa e ómega em indivíduos do sexo masculino (Artigo IV). Quarto, é frequente a interseção entre a extensão póstero-superior da deformidade Cam e a convergência epifisária das estruturas vasculares retinaculares observadas em RM, aspetos que se revestem de primordial importância no planeamento cirúrgico. Adicionalmente a extensão radial da deformidade Cam (ângulo ómega) está significativamente mais relacionada com a sintomatologia clínica pré-cirúrgica do que o parâmetro mais comummente utilizado na prática clínica (ângulo alfa) (Artigo V). A origem das estruturas vasculares observadas por RM na prega retinacular é inequivocamente arterial, sendo que abrange uma extensão mais anterior do que classicamente assumido (Artigo VI). Quinto, as geometrias ovalares (em detrimento das morfologias esféricas e elipsoides) são melhor representativas de ambas as superfícies articulares da coxofemoral, designadamente do fémur e acetábulo, bem como das ancas sintomáticas que clinicamente exibem sinais de CFA (Pincer, Cam e misto) (Artigo VII). Indivíduos com maiores deformidades Cam, aspetos de hipocobertura acetabular e acentuação da anteflexão pélvica apresentam uma maior probabilidade de desenvolverem sintomas articulares (Artigo VIII). Esta observação é crítica, dado que fornece, na prática clínica, informação essencial acerca da potencial predisposição para fenómenos de exacerbação sintomática futura, permitindo desta forma instituição de medidas terapêuticas/preventivas adequadas. Na perspetiva do doente, um diagnóstico precoce e preciso, pode conceptualmente prevenir, numa primeira fase, alterações condropáticas articulares e, numa segunda instância, progressão para artrose estabelecida. Sexto, documentamos resultados clínicos e funcionais significativamente favoráveis quando comparamos a abordagem artroscópica e aberta no tratamento cirúrgico da deformidade Cam, sendo de observar que o género feminino está associado a menor score funcional na avaliação pré-operatória (Artigos IX e X). Futuramente, a imagiologia e a cirurgia conservadora da anca irão desenvolver-se conjuntamente e em paralelo com novos e maiores desafios. A descrição de novos parâmetros analíticos para avaliação da patoanatomia coxofemoral, associada à inovação tecnológica crescente e à implementação da inteligência artificial, impõem uma evolução clínica oposta à assunção de classificações patológicas demasiadamente simplistas. Nesse sentido a existência de guidelines de diagnóstico e terapêutica mais efetivas e baseadas na evidência, que nos levem além da pura diferenciação entre CFA e displasia, são urgentes. A história natural das deformidades Cam e Pincer, sintomáticas ou assintomáticas, é ainda grandemente desconhecida, assumindo-se como uma área determinante de investigação no que concerne ao diagnóstico, terapêutica e prognóstico.ABSTRACT: Conceptually, the preservation of a human anatomical structure makes more sense than its replacement. This concept is even more striking in the case of human joints due to the multitude of unsolved problems related to implants used in orthopaedic surgery. With respect to the hip, joint preservation assumes an increased technical complexity when compared to other joints; this is due to two main reasons: the intra-articular epiphyseal circulation of the femur and the proximity of large neurovascular structures. Femoroacetabular impingement (FAI) and acetabular dysplasia (DHD) in young adults are two common but poorly characterised pathological entities. If undiagnosed and untreated, dysplasia in childhood may lead to residual DHD in young adults, as diagnosed on radiographs, and may also give rise to symptoms such as hip pain and restricted range of motion. The diagnosis of FAI in adults is based on clinical and imaging criteria. The most frequently noticed symptoms of FAI include hip pain and restricted function. Radiologically, two main subtypes of FAI are recognised: The Cam-type, with the pathoanatomical mechanism located on the femoral side, and the Pincertype on the acetabular side. Although with different pathological patterns, both types cause pain and articular damage of the labrum and cartilage. While Cam-type FAI is believed to be a major contributing factor to the early onset of hip osteoarthritis (OA), which eventually requires a total hip replacement, the relationship of other shapes and morphologies with OA are still under debate. Despite the initial promising reports on outcomes following surgical management of these conditions, the best approach to diagnose and manage them still remains controversial. Although for some patients there are unambiguous clinical and imaging findings of FAI, for a substantial number of patients there are minimal or intermediate findings. Moreover, several studies have reported a high prevalence of FAI morphology among the “normal” population and in asymptomatic healthy individuals. At present, there is no adequate imaging tool to facilitate the reliable allocation of all patients into the correct diagnostic group or to confidently rule out diagnosis. However, imaging parameters can be used to describe different hip morphological characteristics and additionally confirm or preclude the diagnosis of FAI.This thesis focuses on assessing hip morphology in different populations by investigating which specific joints are more prone to developing symptoms and by evaluating treatment outcomes of a FAI cohort. Specifically, this research concentrates on the following: 1) examining population-specific (symptomatic and non-symptomatic) characteristics of hip morphology; 2) developing an anatomic-based model to establish “at-risk” hip joints, incorporating subject-specific hip geometries and spinopelvic parameters and 3) investigating treatment outcomes in a Cam-type FAI cohort. In our clinical progression in imaging and in this particular area of pathology, we became aware of the existence of several gaps that we sought to fill with the now published research hereby described. The systematisation by chapters precisely reflects the need to address the issue in simultaneously distinct and complementary areas of knowledge. This thesis consists of six chapters, which cover the entire spectrum from the diagnosis to treatment of the young hip. To present the aims of this thesis in a sequential manner from general morphology to more specific FAI-related topics, the analysis of the asymptomatic hip will be presented first, followed by how joint morphology is associated with symptoms and, finally, will conclude with treatment. In PART I, we introduce the topics that are relevant to understand the full scope of our thesis; we aim to accomplish this by addressing the relevance and contemporariness of the “FAI” theme and by describing the general and vascular anatomy of the hip. Chapter 1 is devoted to hip development and morphogenesis. In Chapter 2, we address the importance of imaging by conducting a thorough review of current and future perspectives on this topic (Paper I). In Chapter 3, we perform a systematic review of the literature to write a state-of-the-art overview, focussing on asymptomatic and symptomatic FAI morphology prevalence and highlighting the multiple gaps in knowledge regarding the role of hip morphology in the pathogenesis of FAI (Paper II). Building on the first part, we address the rationale and aims of this thesis in PART II. In PART III, we describe the original research that was performed and published. Chapter 4 focusses on the detailed characterisation of hip morphology, both osseous and vascular. Bony hip morphology was quantified using a semi-automated software, which allows to robustly study in detail shape variants in an asymptomatic population and their relationship with sex, side and limb dominance (Paper III). Cam morphology was further defined by developing a novel quantitative parameter, with diagnostic and treatment planning capabilities using a cohort of both asymptomatic individuals (Paper IV) and patients undergoing surgery (Paper V). Moreover, we felt the need to better characterise the topography of the deformity and its relationship with the nourishing arteries of the femoral head, as Cam morphology frequently has a posterior a bstr extension that overlaps the retinacular vascular structures. However, its arterial origin has never been described or confirmed in the literature. For this reason, the importance of the aforementioned parameter has been outlined by the cadaveric arterial topographic study of the proximal femur (Paper VI). In Chapter 5, we test multiple parameters and their associated shape variants to detect which ones allow identifying a risk-increased joint in various populations. To this end, we use both advanced computing for shape modelling (Paper VII) and three dimensional (3D) magnetic resonance imaging (MRI) (Paper VIII). Chapter 6 describes the various treatment options (Paper IX) and outcomes in a cohort clinical study, comparing open surgery with arthroscopic surgery in terms of treating Cam deformities (Paper X). The results of the aforementioned chapters are summarised in PART IV, presenting the general synthesis, discussing the results in the light of current literature and detailing the conclusions of this thesis. The scope of potential future research within this field is also presented in this chapter. In brief, this thesis suggests the following: First, detailed imaging assessment of hip morphology is paramount to better understanding both the hip joint and pelvic morphology (Paper I). Second, the case definitions of different morphologies and clinical entities are missing as far as FAI and related disorders are concerned. Qualitative and quantitative radiographic findings thought to be associated with Cam- and Pincer-type FAI, as well as the coexistence between them, are quite common among different populations (Paper II). Third, in adult asymptomatic populations, sex-specific reference intervals for hip measurements for DHD and FAI morphology are wider than currently accepted values (Paper III). Moreover, femoral morphology with distinct Cam magnitudes and epicentres is also sex-specific, with higher mean alpha angle (α°) and omega angle (Ω°) values seen in males (Paper IV). Forth, Cam deformity frequently overlaps with the retinacular vascular structures seen in an MRI; this finding has practical surgical relevance. Additionally, the radial extension of the Cam deformity (Ω°) is more significantly associated with the patients’ symptoms prior to surgery than the α° (paper V). The origin of the vascular structures seen in the retinacular fold is unequivocally arterial in nature, and these structures have a more anterior distribution than classically assumed (Paper VI). Fifth, ovoid geometries are more representative of both articular surfaces of the hip joint as well as of Cam, Pincer and mixed impinged hips when compared to spherical or ellipsoidal shapes (Paper VII). Individuals with larger Cam deformities, decreased acetabular coverage and increased pelvic anteflexion are more likely to experience hip symptoms (Paper VIII). This provides clinicians with indications of how the pathology exacerbates, allowing them to perform the correct clinical assessments and proceed with the correct form of care. From a patient’s perspective, an early and accurate diagnosis could prevent cartilage degradation and progression to OA. Sixth, similar outcomes and significant functional improvement are observed when comparing open and arthroscopic surgery in the treatment of Cam deformities (follow-up time of two years). It should be noted that the female gender was associated with poor hip function in the preoperative evaluation (papers IX and X). Looking ahead, imaging and hip preserving surgery (HPS) will evolve hand-in-hand in the face of new and greater challenges. The increasing number of analytic parameters describing hip joint pathomorphologies as well as new sophisticated 3D imaging-analysis together with emerging artificial intelligence-based technologies have transported us beyond simple classification systems. Moreover, more reliable diagnostic and treatment guidelines that go beyond differentiation into pure FAI and dysplasia are paramount. The largely unknown natural course of both hips with symptomatic FAI and asymptomatic individuals continues to present research opportunities as far as diagnosis, treatment and prognosis are concerned

IC 077 Guide to Texas Medical Center Historical Resources Project Records

The Medical World News Photograph Collection (IC 077) predominantly consists of photographic prints, negatives, and transparencies that document the production of a premiere medical news magazine. The collection contains most of the images published in the magazine from 1967-1985. See more at https://archives.library.tmc.edu/ic-077