There is debate about how fossil hominin pedal morphology relates to terrestrial habits. Were early hominins adapted to a bipedal lifestyle with a significant arboreal component, or were they more dedicated to a terrestrial lifestyle? The proximal articular surfaces of the metatarsals (MT) are examined in Gorilla, Pan, Hylobates, and habitually shod and unshod Homo using three-dimensional morphometrics. The results for MT 1 show three trends. OH 8 (Homo habilis) is indistinguishable from humans, specimens SKX 5017 and SK 1813 (Paranthropus robustus) are apelike, and all other fossil 1st metatarsals are intermediate in shape between humans and apes. The MT 2 and MT 3 analyses show that humans have a narrower surface that is expanded in the plantar aspect relative to apes. These features increase joint stability for the human longitudinal arch. The MT 2 fossils for Stw 573d (Little Foot) and OH 8 are humanlike. The MT 2 specimen of SKX 247 (possibly Paranthropus) is apelike, while all other MT 2 fossils are intermediate between humans and apes. In the MT 3 analysis, Stw 387, Stw 496, Stw 388, and OH 8 metatarsals are humanlike in shape, while Stw 435 and Stw 477 are intermediate between humans and apes. The MT 3 surface of Hylobates is markedly convex, suggesting that the midfoot break in gibbons extends to include this joint in addition to the MT 4 and MT 5 tarsometatarsal joints. The results of the MT 4 analysis show a highly convex surface in apes, with Hylobates extending further to the dorsal aspect of this metatarsal, with a greater range of motion at the midfoot break compared to the African apes. The MT 4 specimens of OH 8 and Stw 628 show greater morphological affiliation with humans. The MT 5 analysis shows that Pan and Hylobates have a medio-laterally extended and concave articular surface that is convex in the dorso-plantar plane. The two human groups are narrower and flatter in the medio-lateral plane, with a little dorso-plantar convexity. There is overlap in shape patterns between groups in the MT 5 analysis. Greatest similarity is between humans and Gorilla. The MT 5 fossil specimens tend to show closer affiliation to humans and Gorilla.

PhD - Science / The study of the human metatarsals reveals frequent morphological variations from the typical descriptions. Pathologies of these bones in contemporary humans are common, and it has been suggested that some of these may be associated with some of these variants. Within this context, it was not clear to what extent footwear and other environmental factors such as modern substrates have influenced metatarsal morphology. This study essentially consists of three parts. First a preliminary morphometric study of the first, second and fifth metatarsals, to demonstrate the broad patterns of discrimination between selected hominoidea, namely humans, gorillas, chimpanzees and orangutans. In addition, the SKX 5017 first metatarsal fossil thought to be of Paranthropus robustus was included. Second, a primary morphometric investigation into the patterns of morphological discrimination in the five metatarsals of selected humans from South Africa, namely Sotho, Zulu, European and pre-pastoral subgroups. The contemporary human subgroups are associated with modern lifestyles and the pre-pastoral individuals represent habitually unshod forager societies from the western and southern Cape, dated 9750 - 2000 B.P. Third, a non-metric investigation into the patterns of variation in epigenetic and pathological variants of the metatarsus of the four human subgroups. A suite of existing metrical data was utilized for the preliminary hominoid study, and a suite of metrical and non-metrical data was collected for the primary human study from appropriate skeletal collections. Univariate analysis of these iv samples revealed important, though simplistic trends in morphology. Subsequent multivariate analyses utilizing principal components and canonical variates analysis were undertaken. Multivariate analysis of the hominoid samples revealed large scale variation between the species. This discrimination was on the basis of genetics, locomotor function and geography. Multivariate analysis of the human metrical data revealed very subtle morphological discrimination within and between the subgroups. Most of this discrimination appears to be genetic, followed by a functional or life-style based discrimination suggesting a broad discrimination between recent humans and the habitually unshod pre-pastoral subgroup. The epigenetic traits reveal considerable variation within groups, with similar trends between them. All subgroups have an appreciable number of identifiable pathological changes, with the recent human subgroups having the most and the prepastoral subgroup the least. In all subgroups, the hallucal metatarsal displays by far the greatest frequency in osseous modification. The main conclusions of this study are: 1.) The general patterns of morphological discrimination between the metatarsals of the human subgroups are very subtle. The non-metric traits are very variable, but do not discriminate between any of the subgroups. 2.) Both recent and ancient human groups present with similar patterns of pathological changes, but the frequency is different, these changes are to a great extent influenced by lifestyle. Regardless of temporal context, no clear correlation between morphological variation and pathological changes could be found.

Morton’s syndrome is a foot condition where the 1st metatarsal does not protrude as far distally as the 2nd metatarsal. Clinicians believe that short 1st metatarsal protrusion affects foot mechanics and leads to painful conditions of the foot. Normal protrusion ratio of the 1st and 2nd metatarsal has not been delineated in scientific literature, and little is known about the mechanics of feet with short 1st metatarsal protrusion beyond anecdotal clinical evidence. In the first part of this two-part study, a novel tool was developed to guide metatarsal measurement and reduce measurement error so values for normal metatarsal protrusion ratios could be established. In the second part, subjects were divided into those with shorter and longer than average 1st metatarsal protrusion ratio and we measured if there were any differences in the foot-floor forces between the two groups. In Part 1, the feet of 65 healthy subjects were measured with a novel measurement tool and it was determined that the average ratio (1st metatarsal/2nd metatarsal) was 0.902, suggesting a 1st metatarsal that does not protrude as far distally as the 2nd metatarsal. For Part 2, participants were divided into two groups: the short 1st metatarsal group had a ratio of more than one standard deviation below the mean (0.866 or lower) while the control group had a metatarsal ratio of more than one standard deviation above the mean (0.938 or higher). We hypothesized that short 1st metatarsal protrusion would cause an imbalance across the forefoot because the 1st metatarsal would not be able to carry the required load on the medial side of the foot; however, the results of the gait study did not show this as only forces in the walking direction near toe-off correlated with metatarsal protrusion ratio. We can only speculate as to the relationship between the metatarsal protrusion ratio and increased shear force in the walking direction, but it is possible that to compensate for the diminished stabilizing capacity of the shorter 1st metatarsal, the foot must push off with more force to propel the body forward. / Thesis (Master, Rehabilitation Science) -- Queen's University, 2013-01-14 14:38:55.255

Antecedentes: El hallux valgus (HV) es la patología del antepié más frecuente en adultos. Una de las técnicas quirúrgicas más ampliamente aceptada para su corrección es la osteotomía en chevron, cuyo objetivo es la realineación del primer metatarsiano mediante el desplazamiento lateral de su cabeza. Actualmente, no se ha determinado qué magnitud constituye un desplazamiento adecuado y satisfactorio para el paciente. Objetivos: El objetivo principal era analizar la influencia de la magnitud del desplazamiento lateral de la cabeza metatarsiana tras la osteotomía distal en chevron del primer metatarsiano sobre los resultados reportados por el paciente. Los objetivos secundarios fueron: (1) Identificar el desplazamiento mínimo de la cabeza metatarsiana necesario para obtener un resultado satisfactorio; (2) Evaluar si la posición sesamoidea cambiaba con el tiempo e influía en el resultado reportado por el paciente. Material y Métodos: Estudio de cohortes, prospectivo y comparativo de una muestra de 97 pacientes. El resultado clínico se evaluó mediante el cuestionario de calidad de vida Self-reported foot and ankle score (SEFAS), escala funcional de la Sociedad Americana del Pie y Tobillo (AOFAS), escala analógica visual del dolor (EVA) y satisfacción final del paciente con una escala Likert. Radiológicamente, el desplazamiento lateral de la cabeza metatarsiana fue cuantificado mediante: a) ángulo intermetatarsiano (AIM); y b) desplazamiento lineal lateral. Los pacientes se distribuyeron en dos grupos según presentaran un incremento postoperatorio mayor o igual o menor de la diferencia mínima clínicamente importante (DMCI) de 9 puntos en la escala SEFAS. Para el objetivo secundario (1) se realizó un análisis ROC, y para el (2) los pacientes se agruparon respecto a la posición sesamoidea obtenida con la cirugía. Resultados: No se encontró asociación significativa entre la magnitud del desplazamiento lateral de la cabeza metatarsiana medido mediante el AIM y la escala SEFAS al final del seguimiento. Aplicando una curva ROC, no se obtuvo un punto de corte significativo en el AIM para discriminar a los pacientes con un incremento igual o mayor a la DMCI en el resultado SEFAS final (área bajo la curva, AUC= 0,46; p= 0,611). Igualmente, no hubo un punto de corte significativo para el desplazamiento lineal lateral (AUC 0,47; p= 0,730). En el análisis multivariante realizado para identificar factores predictores de SEFAS satisfactorio, fueron significativos las variables finales de EVA-dolor y posición correcta de los sesamoideos. Los 66 pacientes con posición sesamoidea normal obtenida en la cirugía no tuvieron cambios en dicha posición al final del seguimiento. Por el contrario, 8 pacientes (25,8%) de los 31 en que la posición no fue correcta tuvieron un empeoramiento de la posición sesamoidea al final del seguimiento, y peor resultado final en SEFAS (p= 0,003), EVA-dolor (p= 0,026) y satisfacción (p= 0,011). Conclusión: La magnitud del desplazamiento de la cabeza metatarsiana no influye en el resultado funcional reportado por el paciente medido con la escala SEFAS, pero tiene influencia en la satisfacción del paciente con la cirugía. Una incorrecta posición sesamoidea obtenida en la cirugía puede conducir a un empeoramiento de dicha posición con el tiempo y peor resultado funcional. El principal factor de resultado favorable no es tanto la magnitud del desplazamiento lateral de la cabeza metatarsiana como la obtención en la cirugía de una correcta cobertura de los sesamoideos.

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Submitted by REGINA DE FATIMA MAZARO DOS SANTOS null (rfmazaro@cta.unesp.br) on 2016-02-29T18:00:29Z No. of bitstreams: 1 tese final Regina 2016.pdf: 1163098 bytes, checksum: d12fd877c5fe9d1b7e6d81131a1999f3 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-03-01T12:53:37Z (GMT) No. of bitstreams: 1 santos_rfm_dr_jabo.pdf: 1163098 bytes, checksum: d12fd877c5fe9d1b7e6d81131a1999f3 (MD5) / Made available in DSpace on 2016-03-01T12:53:37Z (GMT). No. of bitstreams: 1 santos_rfm_dr_jabo.pdf: 1163098 bytes, checksum: d12fd877c5fe9d1b7e6d81131a1999f3 (MD5) Previous issue date: 2016-02-02 / Este trabalho teve como objetivo analisar morfometricamente o tecido ósseo, muscular e cartilaginoso presentes nas articulações tibiotársicas e tarsometatársicas dos membros pélvicos direito e esquerdo, bem como a avaliação macroscópica e histológicados músculos e cartilagens, além de se investigar a densidade mineral óssea e a resistência óssea, de frangos de corte normais e com discondroplasia tibial. Foram utilizados 22 frangos de corte Cobb, com 42 dias de idade, distribuídos em dois tratamentos, que consistiram em dez aves normais e doze com discondroplasia tibial. Os dados foram analisados pelo software SAS. Os resultados evidenciaram que a perda do peso corporal e do membro pélvico de aves discondroplásicas evidenciam comprometimento sistêmico dos frangos e o desuso dos membros, o que acarreta em prejuízos econômicos ao descartar as aves afetadas. As diferenças estruturais observadas pelo aumento de peso em determinados músculos em detrimento de outros mostram que existe uso excessivo de alguns músculos em aves acometidas pela discondroplasia tibial resultando em alterações na marcha dos animais. Os parâmetros de crescimento e qualidade óssea do tibiotarso e metatarso de frangos de corte são influenciados negativamente pela discondroplasia tibial, no entanto, essa enfermidade não afeta a densidade mineral óssea e a resistência óssea dessas aves.O comportamento cartilagíneo observado no presente experimento caracteriza mecanismo compensatório com maior número de condrócitos em aves acometidas pela discondroplasia tibial, evidenciando uma resposta compensatória em relação às alterações morfofisiológicas dos ossos e músculos. / This study aimed to analyze morphometric bone, muscle and cartilage tissues present in the tibiotarsus and tarsometatarsal articulation of right and left hind limbs, to perform macroscopical and histological examination of muscles and cartilage, and to investigate bone mineral density and bone strengthin normal broiler chicks presenting tibial dyschondroplasia. A total of 22 Cobb broiler chicks with 42 years of age were enrolled into two experimental groups, which consisted of 10 normal birds and 12 chicks presenting tibial dyschondroplasia. Data obtained were analyzed by SAS software. The results showed that the body weight and hindlim blosses in chicks with tibial dyschondroplasia had evident systemic involvement and disuse members, which results in economic losses due to discard of affected chicks. Structural differences observed and caused by weight gain in certain muscles showed that there was an overuse of certain muscles in birds with tibial dyschondroplasia resulting in gait disturbance in those birds. The growth, tibiotarsus and metatarsa bones quality parameters in broiler chicks are negatively influenced by tibial dyschondroplasia, however, this disease does not affect bone mineral density and bone strength of these birds. The cartilage behavior observed in this experiment characterized a compensatory mechanism involving a largest number of chondrocytes in birds affected by tibial dyschondroplasia, indicating a compensatory response in relation to morphological and physiological changes in the bones and muscles.

付記する学位プログラム名: 充実した健康長寿社会を築く総合医療開発リーダー育成プログラム / 京都大学 / 0048 / 新制・課程博士 / 博士(人間健康科学) / 甲第22388号 / 人健博第74号 / 新制||人健||5(附属図書館) / 京都大学大学院医学研究科人間健康科学系専攻 / (主査)教授 黒木 裕士, 教授 高桑 徹也, 教授 妻木 範行 / 学位規則第4条第1項該当 / Doctor of Human Health Sciences / Kyoto University / DFAM

The Mio-Pliocene age Gray Fossil Site of northeastern Tennessee has the largest collection of tapir postcranial skeletons in the world. Though representing a single species, a few localized structures show high variability. This paper deals with variation of the first metatarsal, which in tapirs was reduced as an early adaptation for running and then retrofitted to serve as a special origin for flexors and adductors of the proximal phalanges. The first metatarsal connects the medial ankle with a posterior process of the third metatarsal in tapiroids. In Tapirus indicus, T. webbi, and 6 out of 31 T. polkensis feet at Gray, it extends more laterally to articulate with the fourth metatarsal. This condition is too variable for species distinction but is correlated with a decrease in the metatarsophalangeal joint facet, suggesting a mobility reduction likely related to the increased range and feeding strategy seen in extant T. indicus.

In vivo studies of mechanical loading on bone have suggested that load magnitude is one of the parameters that play a vital role in bone adaptation. This study examined how longitudinal growth of immature rat metatarsals is affected by different load magnitudes. The main hypotheses were that the longitudinal growth of immature bone would decrease with increased compressive load magnitude, and that the longitudinal growth would be more decelerated the higher the load mag- nitude. The three middle metatarsal bones in the back paws of 19-20 days old Sprague-Dawley rat fetuses were extracted. Metatarsal bones were loaded with 0.05 N, 0.25 N, 1.25 N and 6.25 N. Loading rate and number of cycles were constant at 0.01 mm/sec and 10 cycles respectively. Length measurements occurred every 2-3 day. Concluded from the study was that a load magni- tude of 0.05 N resulted in an increased longitudinal growth, compared to unloaded bones. For the other load magnitudes the results were insufficient and inconsistent and therefore nothing could be suggested for them. The problem remained as before and further studies are needed.