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J M Le Minor

Publications and source records attributed to J M Le Minor.

At least 19 recordsLinked to original sources

Intrinsic proportions of the human tarsus: an original approach to tarsal biometry.

Few precise biometrical data on human tarsal bones are available, and those published consist principally of linear and angular measurements made on dried bones or on radiographs. The material consisted of 86 complete adult human tarsi (dried bones). The tarsal proportions were determined using the relative tarsal weights (Weight of each of the seven tarsal bones/Weight of the total tarsusx100). The calcaneus was the greatest tarsal bone (41.95%), and the talus the second-largest (28.45%). The medial cuneiform, the cuboid, and the navicular had very similar proportions (7.00-8.38%), as did the intermediate and lateral cuneiforms (2.98% and 3.81%). The study of the ranks of each bone by decreasing proportion allowed the determination of individual variability. The posterior tarsal row was considerably larger (70.40%) than the anterior row (29.60%), resulting in an antero-posterior ratio of 0.42. The medial and lateral tarsal columns had quite similar proportions (50.63% and 49.37%), resulting in a latero-medial ratio of 0.98. The intrinsic tarsal proportions are fundamental biometrical data which seem to be of interest for a better characterization of the human foot in clinical practice and for quantitative approaches in functional and comparative morphology and in paleontology.

Adult↗

Sexual dimorphism of the human mandible: demonstration by elliptical Fourier analysis.

A new quantitative approach of the mandibular sexual dimorphism, based on computer-aided image analysis and elliptical Fourier analysis of the mandibular outline in lateral view is presented. This method was applied to a series of 117 dentulous mandibles from 69 male and 48 female individuals native of Rhenish countries. Statistical discriminant analysis of the elliptical Fourier harmonics allowed the demonstration of a significant sexual dimorphism in 97.1% of males and 91.7% of females, i.e. in a higher proportion than in previous studies using classical metrical approaches. This original method opens interesting perspectives for increasing the accuracy of sex identification in current anthropological practice and in forensic procedures.

Female↗

Relative weights of the human carpal bones: biological and functional interests.

The relative carpal weights (Weight of each of the eight carpal bones/Weight of the complete carpus x 100) were studied in a series of 95 complete human adult carpi (dried bones). The greatest was the capitatum (19.92%; mean rank 1.16) and the smallest the pisiform (4.43%; mean rank 8.00). The scaphoideum and the hamatum presented very near values (17.19 and 15.81%; mean ranks 2.34 and 2.74), as did the lunatum and trapezium (12.56 and 12.52%; mean ranks 4.41 and 4.48), and the triquetrum and trapezoideum (9.21 and 8.36%; mean ranks 6.19 and 6.68). Within the proximal row, a regular radio-ulnar decrease was observed from the scaphoideum (39.58%) to the pisiform (10.20%). Within the distal row, a marked break existed between the trapezoideum (14.77%) and the capitatum (35.19%); the capitato-hamatal element represented 63.11% of the distal row. The distal row (mean 56.61%) was always a little heavier than the proximal row (mean 43.39%), resulting in a mean proximo-distal weight ratio of 0.77. A radio-ulnar decrease in the relative weights was observed from the radial to the ulnar carpal columns. The determination of the relative carpal weights is simple, reproducible, non-invasive, rapid, and inexpensive, and can be considered an interesting and valuable approach to the estimation of the relative carpal volumes. Relative carpal weights reveal the intrinsic proportions of the carpus and are the reflection of biological, functional and evolutionary constraints. Interesting relations appear with carpal growth and ossification, with functional characteristics, and with evolutionary processes.

Adult↗

Congenital absence of the lateral metatarso-phalangeal sesamoid bone of the human hallux: a case report.

A case of congenital absence of the lateral metatarsophalangeal sesamoid bone of the hallux is reported, in a 47-year-old woman. The lateral sesamoid bone was absent on the right hallux, and extremely reduced on the left hallux. The normal intersesamoidean crest and both sesamoidean grooves of the metatarsal head were absent. Physical examination was normal, and no functional disturbance resulted from this variant. Only two previous cases have been found in the literature. It must be distinguished from a total resorption due to an infectious process, or from an absence due to surgical excision. This absence can be related to the general tendency of disappearance of the sesamoid bones within hominoid primates.

Ankle Injuries↗

Importance of elliptic Fourier methods for morphometry of complex outlines: application to the distal human femur.

The purpose of this technical note is to present an automatic procedure of shape characterisation using new developments in elliptical Fourier methods combined with image analysis techniques. It was applied, as an example, to the outline of the distal extremity of the distal human femur in inferior axial view. This outline was automatically extracted and characterised by an ordered series of harmonics, each harmonic being described by four new parameters called elliptical descriptors. Step by step reconstructions of outlines using an increasing number of harmonics were than performed. The simultaneous study of the elliptic descriptors and of the step by step reconstructions allowed a considerably easier geometric and morphologic interpretation of the harmonic contributions than classically. The main morphologic features of the distal femur (lateral and medial condyles, intercondylar fossa, lateral and medial borders of the articular surface, and patellar groove) were mainly described by the first seven harmonics. These new developments in elliptic Fourier methods open interesting perspectives for the study of complex outlines, providing an accurate individual morphologic characterisation, and thus the possibility of polymorphic analysis.

Anthropometry↗

Shape of the orbital opening: individual characterization and analysis of variability in modern humans, Gorilla gorilla, and Pan troglodytes.

The description of the human orbital shape is principally qualitative in the classical literature, and characterised by adjectives such as circular, rectangular or quadrangular. In order to provide a precise quantification and interpretation of this shape, a study based on automatic image analysis and Fourier analysis was carried out on 45 human skulls (30 males, 15 females), and for comparison on 61 skulls of Gorilla gorilla (40 males, 21 females), and 34 skulls of Pan troglodytes (20 males, 14 females). Sexual dimorphism in the shape of the orbital opening was not demonstrated. Its dominant morphological features could be characterized by Fourier analysis; elliptical elongation and quadrangularity were dominant morphological features of the shape of the orbital opening in the three species. Elliptical elongation was more marked in humans and Pan, whereas quadrangularity was particularly emphasized in Gorilla. An intraspecific variability of the shape of the orbital opening existed in humans, Gorilla and Pan, and seemed close in the three species. Interspecific partition between humans, Gorilla and Pan was demonstrated despite the variability observed in the three species studied. Interspecific differences between Gorilla and the Pan-humans group were principally explained by the differences in quadrangularity, and by differences in orientation of triangularity and pentagonality. Differences in the shape of the orbital opening between humans and Pan were principally explained by differences in hexagonality, and by differences in orientation of quadrangularity. A closeness of shape between some humans and some individuals in Pan and, to a lesser degree, with some individuals in Gorilla was observed, demonstrating the existence of a morphological continuum of the shape of the orbital opening in hominoids.

Animals↗

Shape of the piriform aperture in Gorilla gorilla, Pan troglodytes, and modern Homo sapiens: characterization and polymorphism analysis.

By using new methodologies based on automatic image analysis, the shape of the piriform aperture was analyzed in Gorilla gorilla (33 males, 13 females), Pan troglodytes (35 males, 22 females), and modern Homo sapiens (30 males, 12 females). The determination of the piriform aperture index (breadth/height) allowed the authors to demonstrate a marked elongation of the aperture in Homo compared with Gorilla and Pan. Individual characterization of the shape was possible with great precision and without ambiguity by using Fourier analysis. An absolute, interspecific partition between Gorilla, Pan, and Homo resulted from the canonical discriminant analysis of the Fourier descriptors. However, a closeness of shape between some individuals in Pan and some in Gorilla and Homo was observed, demonstrating a morphological continuum of the shape of the piriform aperture in hominoids: Pan was in intermediate position between Gorilla and Homo. Interspecific differences between Homo and the group Pan-Gorilla were explained principally by the differences in elongation (amplitude of the second harmonic) and pentagonality (amplitude of the fifth harmonic) and by differences in orientation of quadrangularity (phase of the fourth harmonic). Differences in the shape of the piriform aperture between Pan and Gorilla were explained by differences in orientation of elongation (phase of the second harmonic) and by differences in the component of triangularity (amplitude of the third harmonic). In Gorilla and Pan, the little, elongated, and relatively trapezoidal piriform aperture seems to be a shared primitive feature (plesiomorphic), whereas an elongated piriform aperture seems to be a characteristic and derived feature (apomorphic) of modern Homo sapiens.

Animals↗

New approaches to human facial morphology using automatic quantification of the relative positions of the orbital and nasal apertures.

The purpose of this study was to define and quantify the relative positions of the orbital and nasal apertures in the human face. The material consisted of 44 skulls (32 males, 12 females). For each skull, an image of the projection of the face was captured perpendicular to the palatal plane, using a CCD camera. The orbital and nasal apertures were segmented and characterized using classical image analysis procedures. New quantitative parameters were automatically determined from the centres of area of the facial apertures, and from horizontal and vertical lines of reference. Sexual differences were only significant for orbital height, nasal height, and orbitonasal height. A medio-lateral orbitonasal overlap, as well as a vertical orbitonasal overlap, existed in all individuals; the vertical overlap was always much more marked than the medio-lateral overlap. Significant proportions of the human face were also demonstrated: on average, the interorbital breadth corresponded to a fifth of the biorbital breadth, and thus to half of the mean orbital breadth; the nasal breadth corresponded to one fourth of the biorbital breadth, and the vertical orbitonasal overlap to one fourth of the orbitonasal height. Some instructive significant correlations were observed between these new parameters. The applications of the present methodology seem of great potential interest in anthropology and clinical biometry.

Adult↗

The retrotransverse foramen of the human atlas vertebra. A distinctive variant within primates.

The occurrence of a retrotransverse foramen of the atlas has been investigated in a series of 409 nonhuman primates representative of 40 genera, and in a series of 500 human atlases (dried bones). In nonhuman primates, no retrotransverse foramen was found in any of the individuals studied. In humans, the retrotransverse foramen was observed in 71 cases (14.2%). It was present bilaterally in 21 cases (29.6% of the 71 foramina), and unilaterally in 50 cases (70.4%). The foramen was present in 44 cases on the right side, and 48 on the left side. The character was noted as present only if it was complete; partial forms were not recorded. Various aspects of the retrotransverse foramen were observed. The present observations suggest that the retrotransverse foramen is a uniquely derived trait (autapomorphy) within primates which is restricted to some individuals in Homo sapiens. Appearance of this foramen in human evolution can be related to the acquisition of the erect posture and bipedal locomotion, and consecutive modifications of the regional venous circulation.

Animals↗

Relative position and extent of the nasal and orbital openings in Gorilla, Pan and the human species from the study of their areas and centres of area.

In order to quantify the relative position and extent of the nasal and orbital openings in hominoid primates, a new methodology based on image analysis was developed and applied to a series of 134 hominoid skulls (52 Gorilla gorilla; 30 Pan troglodytes; 44 Homo sapiens, and, as comparison material, 8 Pongo pygmaeus). The areas and the centres of area of the orbital and nasal openings were determined automatically. The orbitonasal triangle connecting these three centres of area was then constructed. This triangle was used to quantify the elongation of the face. It was most elongated in gorilla, shortest in the human species and intermediate in Pan; the elongation in Pongo was close to that in Gorilla. The proportions of the areas of the orbital and nasal openings in the face were related to the extent of the bony structures of the midface and were thus used to quantify the facial robustness. A robust face was demonstrated in Gorilla, but a gracile face in the human species. Robusticity in Pan was intermediate.

Anatomy, Comparative↗

Biphalangeal and triphalangeal toes in the evolution of the human foot.

The number of phalanges of the human toes was investigated in a series of 2,550 radiographs. Classical triphalangia of the lateral toes (2-5) was observed in 1,440 cases (56.47%). Biphalangeal disposition was observed for the 5th toe in 1,110 cases (41.02%), for the 4th toe in 64 cases (2.51%), for the 3rd toe in 5 cases (0.20%), and for the 2nd toe in 3 cases (0.12%). The frequency of biphalangia of a given toe was not independent of the others. Biphalangeal toes result primarily from the absence of development of the distal interphalangeal joint. Biphalangia of the toes is a derived character which is restricted, within primates, to the human species, in relation to the reduction of the toes in adaptation to bipedalism.

Adult↗

[The treatise "Nouveaux eléments d'anatomie descriptive" of H. Beaunis and A. Bouchard (1868)].

The treatise of anatomy of H. Beaunis (1830-1921) and A. Bouchard (1833-1899) published in 1868, had an important influence on the French anatomical sciences for more than thirty years. New editions were published in 1873, 1880, 1885, and the last in 1894. Both authors were professors at the Faculty of Medicine of Strasbourg, and tutors at the French Military Medical School established in Strasbourg. The 406 black-and-white woodcut ilustrations are mostly original. They were principally based on the drawings of E. Schweitzer (1837-1903) and A. Chuquet (1811-1899), both of whom lived in Strasbourg. Most of the illustrations were engraved by the Alsatian J. Lévy (1843-1918).

Anatomy↗

The sesamoid bone of musculus abductor pollicis longus (os radiale externum or prepollex) in primates.

The sesamoid bone of the musculus abductor pollicis longus has been investigated in a series of 276 nonhuman primates representative of 37 genera, and in a series of 300 radiographs of human subjects. The presence of this ossicle in primates is a primitive characteristic. It is present in all nonhuman primates, and is generally articulated with both the scaphoid and trapezium. Modifications of the general mammalian pattern exist only in Gorilla gorilla, where the sesamoid bone is observed in about half of the individuals, and in Homo, where this ossicle is normally absent.

Animals↗