The joint between the arytenoid cartilage and the cricoid cartilage is one of the smallest in the body. Its existence has been known since, if not before, the time of Galen (130-201 A.D.). However, little anatomical study has been carried out on this synovial joint and publications based on research into its exact anatomy and function are few. The results of these studies have been rarely questioned or scientifically re-examined, with the consequence that authoritative anatomical texts have perpetuated unconfirmed ideas of the behaviour of the cricoarytenoid joint. The purpose of this thesis is to present in detail the results of research into the anatomy and the functions of the cricoarytenoid joint and of the muscles that act upon it. This research began in 1977 with the dissection of 45 cadaver larynges. In this initial study the most striking anatomical finding was the identification of the so-called "posterior" cricoarytenoid ligament, of which inadequate and often incorrect detail has been presented in standard anatomy texts. Another surprising finding of this work was the variability of the shape and positions of the two cricoid facets. In 1978 these findings were published in detail (Sellars and Keen). An attempt to understand the accepted muscular control of the cricoarytenoid joint led to further research. This was carried out by the dissection of a further 23 larynges, with special care to examine the exact origin, direction and insertion of each muscle concerned. Six of these larynges, which had been surgically excised, were also stimulated electrically immediately after excision and the resultant arytenoid cartilage movements were recorded and analysed. The findings of this study were published in 1978 (Sellars) and these articles (Sellars and Keen, 1978; Sellars, 1978) are referred to in "Gray's Anatomy" and in Grant's "Method of Anatomy" (Sellars and Keen, 1978). Further examination of the reactions of these intrinsic laryngeal muscles to electrical stimulation has since been done on three additional fresh operative specimens. This additional work on laryngeal muscle action suggests that the explanation of specific intrinsic laryngeal muscle actions made in the earlier publication (Sellars, 1978) had been oversimplified. The main experimental work, on which this thesis is based, attempts to clarify and interpret the highly complex synchronized muscle actions that occur at the cricoarytenoid joint. Relevant facts found in both recent and old publications relating to this subject are presented and discussed. Before the review of literature is presented the embryology and basic anatomy of the larynx are described.

No description available.

Enquanto o papel dos enxertos cartilaginosos na reconstrução da lamela interna palpebral está bem estabelecido, o crescimento da conjuntiva sobre ele, proveniente de áreas adjacentes, necessita de comprovação mais aprofundada. Este estudo tem como objetivos analisar comparativamente, após a reconstrução palpebral inferior com enxertos de cartilagem auricular conchal com e sem pericôndrio, em ambas as pálpebras inferiores de coelhos, a presença de crescimento conjuntival sobre os enxertos, a área de epitelização conjuntival sobre eles, a integridade da estrutura corneana dos globos oculares em contato com os enxertos cartilaginosos e a presença de alterações das áreas dos enxertos de cartilagem com e sem pericôndrio, após sua implantação. Foram utilizados, para o experimento, 50 coelhos albinos adultos da raça New Zealand (Oryctolagus cuniculus), entre 3 e 4 meses de vida, com pesos médios variando de 2,5 a 3,0 quilogramas no início do experimento, provenientes do biotério da Faculdade de Medicina da Universidade de São Paulo. Cem pálpebras inferiores foram reconstruídas em sua lamela interna, com enxertos autógenos de cartilagem auricular conchal, e cobertos com retalho miocutâneo. As pálpebras do lado direito receberam enxerto de cartilagem com pericôndrio posicionado em contato direto com o globo ocular, enquanto as do lado esquerdo foram reconstruídas da mesma forma, porém com enxertos cartilaginosos sem pericôndrio. A cada semana, em um total de 5 semanas, eram sacrificados 10 animais após a reconstrução palpebral, e suas pálpebras inferiores foram analisadas macroscópica e histologicamente. A planimetria digital demonstrou que, com 5 semanas, a área média das cartilagens com pericôndrio apresentava redução de 8,33%, e a área média das cartilagens sem pericôndrio encontravase reduzida em 18,52%. Detectou-se, em cada semana de avaliação, que as áreas das cartilagens com pericôndrio se apresentaram significativamente maiores do que aquelas sem pericôndrio nas semanas 4 e 5 (p=0,0003 e p=0,0001, respectivamente), e uma tendência para significância na semana 2 (0,0706). Na primeira e terceira semanas, a diferença entre as áreas se manteve igual (p=0,8583 e p=0,2092). Em relação ao crescimento conjuntival, observouse que a diferença porcentual do crescimento sobre as cartilagens com e sem pericôndrio foi de 11,41% na primeira semana do experimento, de 13,64% na segunda semana, de 18,69% na terceira, de 10,38% na quarta, e de 6,17% na quinta. Observou-se, em cada semana do experimento, que a porcentagem média de crescimento da conjuntiva nas pálpebras reconstruídas com enxerto condro-pericondral apresentou-se significativamente maior do que aquelas apenas com enxerto cartilaginoso nas 5 semanas do experimento (p<0,0001). Observou-se que houve crescimento conjuntival sobre os enxertos de cartilagem em contato direto com o globo ocular, ocorrendo tanto nas cartilagens com pericôndrio, como naquelas que não o possuíam. A área de cobertura conjuntival com 5 semanas nas cartilagens com pericôndrio, foi maior do que a observada nas cartilagens sem pericôndrio. Não houve ceratite ou úlceras de córnea na maioria da amostra estudada e houve diminuição das áreas dos enxertos cartilaginosos em graus variados, com maior intensidade nos enxertos sem pericôndrio. / Although the role of cartilage grafts in reconstruction of the posterior eyelid lamella is well established, conjunctival epithelialization on such grafts has yet to be fully proven. The aim of this study is to perform a comparative analysis, after inferior eyelid reconstruction in rabbits with cartilage grafts with and without perichondrium, the presence of conjunctival epithelialization over conchal cartilage grafts, the area of conjunctival epithelialization over those grafts, the integrity of the corneal structure in contact with the cartilage grafts and the variation of the areas of the cartilage grafts with and without perichondrium. Fifty adult albino New Zealand rabbits (Oryctolagus cuniculus) between 3 and 4 months of age with average weights from 2.5 to 3.0 kilograms from the University of São Paulo Medical School animal colony were used for the experiment. The posterior lamellae of 100 lower eyelids from were reconstructed with autogenous grafts of conchal ear cartilage and covered with a myocutaneous flap. In the right eyelids, cartilage was grafted with the perichondrium in direct contact with the eyeball, while the left eyelids were reconstructed in a similar manner but using cartilage grafts without perichondrium. The animals were sacrificed after 1, 2, 3, 4 and 5 weeks after eyelid reconstruction, and their lower eyelids were analyzed macroscopically and histologically. The digital planimetry has demonstrated that in the first week of the experiment there was a reduction of 8,33%, in the average area of the cartilages with perichondrium and a reduction of 18,52% in the average area of the cartilages with perichondrium. The average areas of the cartilages with perichondrium were significantly larger than those on cartilages without perichondrium in weeks 4 and 5 (p=0,0003 and p=0,0001, respectively) and tended to vary over the week 2 (0,0706). No difference was noted between the areas in weeks 1 and 3 (p=0,8583 and p=0,2092). When the conjunctival growth was assessed, it was found that the percentage difference in conjunctival epithelialization on the cartilage with perichondrium and that without perichondrium was 11.41% in the first week of the experiment, 13.64% in the second week, 18.69% in the third, 10.38% in the fourth and 6.17% in the fifth. The average percentage conjunctival epithelialization in the eyelids reconstructed with a cartilage graft with perichondrium was significantly higher for the five weeks of the experiment than that in the eyelids reconstructed with cartilage without perichondrium (p<0.0001). It was found that there was conjunctival growth on the cartilage grafts with and without perichondrium when they were placed in direct contact with the eye. The area of the epithelialization on cartilages with perichondrium was larger than that on cartilages without perichondrium in week 5. Neither keratitis nor corneal ulcers were observed during the 5 weeks of the experiment in the majority of the animals operated on and there was reduction in the areas of the grafts in various degrees, with larger intensity in the grafts without perichondrium.

Enquanto o papel dos enxertos cartilaginosos na reconstrução da lamela interna palpebral está bem estabelecido, o crescimento da conjuntiva sobre ele, proveniente de áreas adjacentes, necessita de comprovação mais aprofundada. Este estudo tem como objetivos analisar comparativamente, após a reconstrução palpebral inferior com enxertos de cartilagem auricular conchal com e sem pericôndrio, em ambas as pálpebras inferiores de coelhos, a presença de crescimento conjuntival sobre os enxertos, a área de epitelização conjuntival sobre eles, a integridade da estrutura corneana dos globos oculares em contato com os enxertos cartilaginosos e a presença de alterações das áreas dos enxertos de cartilagem com e sem pericôndrio, após sua implantação. Foram utilizados, para o experimento, 50 coelhos albinos adultos da raça New Zealand (Oryctolagus cuniculus), entre 3 e 4 meses de vida, com pesos médios variando de 2,5 a 3,0 quilogramas no início do experimento, provenientes do biotério da Faculdade de Medicina da Universidade de São Paulo. Cem pálpebras inferiores foram reconstruídas em sua lamela interna, com enxertos autógenos de cartilagem auricular conchal, e cobertos com retalho miocutâneo. As pálpebras do lado direito receberam enxerto de cartilagem com pericôndrio posicionado em contato direto com o globo ocular, enquanto as do lado esquerdo foram reconstruídas da mesma forma, porém com enxertos cartilaginosos sem pericôndrio. A cada semana, em um total de 5 semanas, eram sacrificados 10 animais após a reconstrução palpebral, e suas pálpebras inferiores foram analisadas macroscópica e histologicamente. A planimetria digital demonstrou que, com 5 semanas, a área média das cartilagens com pericôndrio apresentava redução de 8,33%, e a área média das cartilagens sem pericôndrio encontravase reduzida em 18,52%. Detectou-se, em cada semana de avaliação, que as áreas das cartilagens com pericôndrio se apresentaram significativamente maiores do que aquelas sem pericôndrio nas semanas 4 e 5 (p=0,0003 e p=0,0001, respectivamente), e uma tendência para significância na semana 2 (0,0706). Na primeira e terceira semanas, a diferença entre as áreas se manteve igual (p=0,8583 e p=0,2092). Em relação ao crescimento conjuntival, observouse que a diferença porcentual do crescimento sobre as cartilagens com e sem pericôndrio foi de 11,41% na primeira semana do experimento, de 13,64% na segunda semana, de 18,69% na terceira, de 10,38% na quarta, e de 6,17% na quinta. Observou-se, em cada semana do experimento, que a porcentagem média de crescimento da conjuntiva nas pálpebras reconstruídas com enxerto condro-pericondral apresentou-se significativamente maior do que aquelas apenas com enxerto cartilaginoso nas 5 semanas do experimento (p<0,0001). Observou-se que houve crescimento conjuntival sobre os enxertos de cartilagem em contato direto com o globo ocular, ocorrendo tanto nas cartilagens com pericôndrio, como naquelas que não o possuíam. A área de cobertura conjuntival com 5 semanas nas cartilagens com pericôndrio, foi maior do que a observada nas cartilagens sem pericôndrio. Não houve ceratite ou úlceras de córnea na maioria da amostra estudada e houve diminuição das áreas dos enxertos cartilaginosos em graus variados, com maior intensidade nos enxertos sem pericôndrio. / Although the role of cartilage grafts in reconstruction of the posterior eyelid lamella is well established, conjunctival epithelialization on such grafts has yet to be fully proven. The aim of this study is to perform a comparative analysis, after inferior eyelid reconstruction in rabbits with cartilage grafts with and without perichondrium, the presence of conjunctival epithelialization over conchal cartilage grafts, the area of conjunctival epithelialization over those grafts, the integrity of the corneal structure in contact with the cartilage grafts and the variation of the areas of the cartilage grafts with and without perichondrium. Fifty adult albino New Zealand rabbits (Oryctolagus cuniculus) between 3 and 4 months of age with average weights from 2.5 to 3.0 kilograms from the University of São Paulo Medical School animal colony were used for the experiment. The posterior lamellae of 100 lower eyelids from were reconstructed with autogenous grafts of conchal ear cartilage and covered with a myocutaneous flap. In the right eyelids, cartilage was grafted with the perichondrium in direct contact with the eyeball, while the left eyelids were reconstructed in a similar manner but using cartilage grafts without perichondrium. The animals were sacrificed after 1, 2, 3, 4 and 5 weeks after eyelid reconstruction, and their lower eyelids were analyzed macroscopically and histologically. The digital planimetry has demonstrated that in the first week of the experiment there was a reduction of 8,33%, in the average area of the cartilages with perichondrium and a reduction of 18,52% in the average area of the cartilages with perichondrium. The average areas of the cartilages with perichondrium were significantly larger than those on cartilages without perichondrium in weeks 4 and 5 (p=0,0003 and p=0,0001, respectively) and tended to vary over the week 2 (0,0706). No difference was noted between the areas in weeks 1 and 3 (p=0,8583 and p=0,2092). When the conjunctival growth was assessed, it was found that the percentage difference in conjunctival epithelialization on the cartilage with perichondrium and that without perichondrium was 11.41% in the first week of the experiment, 13.64% in the second week, 18.69% in the third, 10.38% in the fourth and 6.17% in the fifth. The average percentage conjunctival epithelialization in the eyelids reconstructed with a cartilage graft with perichondrium was significantly higher for the five weeks of the experiment than that in the eyelids reconstructed with cartilage without perichondrium (p<0.0001). It was found that there was conjunctival growth on the cartilage grafts with and without perichondrium when they were placed in direct contact with the eye. The area of the epithelialization on cartilages with perichondrium was larger than that on cartilages without perichondrium in week 5. Neither keratitis nor corneal ulcers were observed during the 5 weeks of the experiment in the majority of the animals operated on and there was reduction in the areas of the grafts in various degrees, with larger intensity in the grafts without perichondrium.

The degenerative and traumatic injuries of a spine are very frequent. In those cases it is necessary to stabilize the corresponding spine segment using a spine implant. The spinal implants are rigid or flexible, the latter known as dynamic ones in medical practice. In this thesis, the problems of the physiological spinal segment and the segment with implant were solved using the computational modelling (finite element method). Computational model consists of 4 lumbar vertebrae L2 – L5, intervertebral discs, joints and spinal implants. The spinal segment was loaded by the force 400N and 200N, than by force 200N together with bending moments 2,5Nm and 5Nm depending of the motion. The displacement of the whole system, contact pressure of cartilages, equivalent strain in cancellous bone and equivalent stress in the implant were analyzed. The deformation of the physiological model and the model with the implant are comparable, but the bone tissue of the model with the implant is dramatically more loaded in vicinity of the screws.

Η οστεοαρθρίτιδα αποτελεί μια συχνά εμφανιζόμενη εκφυλιστική ασθένεια. Εντοπίζεται κυρίως στις μεγάλες αρθρώσεις (πχ ισχύο και γόνατο) και χαρακτηρίζεται από προοδευτική φθορά του αρθρικού χόνδρου. Στην παρούσα εργασία έγινε χαρτογράφηση του υγιούς και του οστεοαρθριτικού τμήματος ανθρώπινης κεφαλής μηριαίου οστού η οποία αφαιρέθηκε κατά τη διάρκεια αρθροπλαστικής επέμβασης. Η τεχνική που χρησιμοποιήθηκε ήταν η φασματοσκοπία micro-Raman η οποία παρέχει πληροφορίες που αφορούν στις δονήσεις μορίων. Συγκεκριμένα έγινε δυνατή η ανάπτυξη μεθοδολογίας για τη διαφοροποίηση κολλαγόνου Ι (οστό) και κολλαγόνου ΙΙ (χόνδρος) εξετάζοντας τις φασματικές περιοχές της προλίνης και υδροξυπρολίνης, κάμψεων CH2, CH3 και των αμιδίων Ι και ΙΙΙ. Επίσης η μελέτη των δονήσεων των φωσφορικών ιόντων και των ανθρακικών υποκατασταστατών τους έκανε δυνατή τη διαφοροποίηση του βιοαπατίτη του οστού από τον ασβεστοποιημένο χόνδρο. Η ανάλυση των δεδομένων έδειξε την απουσία αρθρικού χόνδρου στο κέντρο της κεφαλής, που υφίσταται το μέγιστο φορτίο, και την πλήρη αποκάλυψη του υποχόνδρινου οστού. Την εικόνα αυτή διαδέχονται, καθώς κινούμαστε περιμετρικά προς τα άκρα, περιοχές όπου κυριαρχεί ασβεστοποιημένος χόνδρος ή και συνύπαρξη οστού και χόνδρου σαν ένα ενδιάμεσο στάδιο οστεοαρθρίτιδας. Υγιείς περιοχές με εμφανές στρώμα αρθρικού χόνδρου δεν εντοπίζονται παρά μόνο πολύ μακριά από το κέντρο της κεφαλής του μηριαίου οστού. Η χαρτογράφηση περιοχών εσωτερικά, στην επιφάνεια μιας τομής, έδειξε μια σχετικά απότομη μετάβαση από το χόνδρο στο υποχόνδρινο οστό στις υγιείς περιοχές, εικόνα που συνάδει με τα όσα είναι γνωστά για τη δομή της άρθρωσης. Αντίθετα, οι οστεοαρθριτικές περιοχές χαρακτηρίζονταν από την απουσία των φασματικών περιοχών του κολλαγόνου τύπου ΙΙ (χόνδρος) στα εξωτερικά στρώματα αλλά και τη συνύπαρξη των δύο τύπων κολλαγόνου Ι και ΙΙ (οστού και χόνδρου) ή την παρουσία ασβεστοποιημένου κολλαγόνου ΙΙ σε διαδοχικές ζώνες και σε βάθος αρκετών χιλιοστών σε αρκετές περιπτώσεις προς το εσωτερικό της τομής. Τα φασματοσκοπικά αποτελέσματα, τέλος, επιβεβαιώθηκαν από ιστολογική εξέταση με χρώση safranin O της κάθε χαρτογραφημένης περιοχής στην εξεταζόμενη τομή οστεοαρθριτικής κεφαλής μηριαίου οστού. / Osteoarthritis is a very common degenerative disease, characterized by gradual degeneration of the articular cartilage and mainly affecting knees and hip joints. In the present work, a human osteoarthritic femoral head, removed during replacement surgery, was used for the mapping of its healthy and osteoarthritic areas. Laser Raman microscopy, a technique that provides information on molecules’ vibrations, was employed for the study. The development of a methodology for the distinction between collagen I (bone) and collagen II (cartilage) was accomplished through the study of proline, hydroxyproline, CH2, CH3 bending and amide I and III bands. On the other hand, the study of phosphate and carbonate substituents made the distinction between bone bioapatite and calcified cartilage feasible. Data analysis revealed the absence of articular cartilage and the full exposure of subchondral bone in the middle of the outer surface of femoral head section, where maximum friction due to movement is observed. Moving perimetrically from the middle of the outer surface to the rims of the section, areas of calcified cartilage and coexistence of bone and cartilage are observed, possibly as an intermediate disease stage. Healthy areas with distinct layer of articular cartilage are located only on the extreme rims of the section. Mapping of areas in depth of the femoral head section, revealed a relatively abrupt transition from cartilage to subchondral bone in healthy areas, which is consistent with our knowledge about joint structure. On the contrary, osteoarthritic areas were characterized by the absence of collagen II (cartilage) characteristic bands on the outer layers and in the same time by the coexistence of collagen I and II (bone and cartilage) or the presence of calcified collagen II through successive layers in some millimeters depth towards the interior of the femoral head section. Finally, spectroscopic results were confirmed by histological examination and Safranin O histochemical staining of each area mapped of the human femoral head section.

Articular cartilage covers the articulating ends of diarthrodial joints. It plays a vital role in the function of the musculoskeletal system by allowing almost frictionless motion to occur between the articular surfaces of a diarthrodial joint. Study of cartilage contact behavior will help to understand the intrinsic biomechanical properties related to cartilage degeneration and related pathology. In order to study the mechanical behavior of the cartilage a FEM based computational model of the knee-joint was developed from MRI data. A heuristic algorithm was developed based on Image processing techniques using Evolve2D toolbox and edge detection. An indigenous path following algorithm to capture minute details of bone and soft tissue curvature was developed using Image Processing Toolbox of Matlab. Parts including femur, tibia, femoral and tibial cartilages, lateral & medial menisci were extracted as a point cloud from each of the slices and rendered into a 3D model using GUI driven CAD package RHINOCEROS 4.0. Commercial FE software HYPERMESH 9.0 was used to develop FE model from geometric model. Cartilage and Menisci were modeled using eight node hexahedral elements and bones were modeled using four node quadrilateral elements. Bones were assumed to be rigid. Cartilage and menisci were assumed to be linearly elastic, isotropic and homogenous. The knee joint was subjected to a uniaxial compressive load with tibia remaining fixed and femur subjected to two primary boundary conditions: 1.Flexion - extension and Varus - Valgus rotation constrained; 2.Only Varus - Valgus rotation constrained. Parameters such as contact area, contact pressure, contact force, centre of contact pressure, mises stress distribution; maximum and minimum principal stresses were studied at maximum compressive load condition and also in intermittent steps. This model considered both geometric and contact non-linearity. From the FE analysis, it was observed that peak contact deformation and contact area on both femoral and tibial medial cartilage was found to be greater than the lateral side under full extension condition. More than 50% of the load transmission was through the medial side - which could be an indication of cartilage degeneration. Deformation of lateral meniscus was more than the medial meniscus under angular constrained conditions. Loading history during intermittent steps suggested that contact area on lateral tibial cartilage increased with load, indicating joint asymmetry. These results indicate the importance of the rotational constraints (boundary conditions) and represent more accurate physiological behavior of knee joint. Role of menisci in this study was analyzed, which indicated that consideration of menisci is essential in biomechanical estimation of load transmission. In conclusion, detailed segmentation to develop geometric model, precise boundary conditions & time dependent behavior of cartilage and menisci helped in understanding knee joint load bearing capacity to a better accuracy and can potentially give rise to designing better cartilage implants.