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Biomedical subjects

J Koebke

Publications and source records attributed to J Koebke.

At least 127 records · Page 7Linked to original sources
PubMed1982

Morphological and functional studies on the lateral joints of the first and second cervical vertebrae in man.

The articular surfaces of the lateral atlanto-axial joints in man were analyzed with respect to their biomechanical aspects. The joint surfaces were investigated macroscopically, and the texture of the tangential fiber layer of the articular cartilage was studied with the aid of the split-line method. Furthermore, the thickness of cartilage was measured. From the results obtained the authors draw the conclusion that especially the mode of rotational movement between C1 and C2 changes within a life time. As a consequence, the distribution of stress in the lateral atlanto-axial joint is modified.

Adolescent↗
PubMed1982

[The dorsal metacarpal ligament I and arthrosis of the saddle joint of the thumb].

Morphology and function of the Ligamentum metacarpeum dorsale I are investigated. The ligament connects the capsule of the Articulatio carpometacarpea pollicis with the base of the second metacarpal bone. The ligament is responsible for the security and passive guidance of movements in the saddle joint of the thumb. In the course of an arthrotic affection of the Articulatio carpometacarpea pollicis the ligament is exposed to increased tensile stresses. The excessive mechanical stress often leads to partial ossification of the ligament. The ossification is radiologically identified as a spurlike protrusion at the base of the second metacarpal bone. The evaluation of clinical X-rays reveals, that an osseous spur can develop before the saddle joint of the thumb shows alterations. From this the bony spur is important for an early diagnosis of the rhizarthrosis.

Aged↗
PubMed1980

[Anatomical investigations on the lower leg and foot in cases of hypoplasia and aplasia of the tibia (author's transl)].

Deformities associated with absence or defect of the tibia were investigated on 3 lower legs and feet. In case of bilateral hypoplasia of the tibia, the deformities are nearly identical regarding the muscles and the skeletal system. The main vessels and nerves are developed normally. The extent of malformations seems to be greater in case of aplasia of the tibia. The question, wether some abnormalities typical for a defect of the tibia exist, is discussed. For this our own observations are compared with similar cases described in the literature.

Adolescent↗
PubMed1980

[Anatomical findings in hands with a triphalangeal thumb].

The muscles of the two triphalangeal thumbs of an adult female show characteristics typical for a thumb but also for one of the other fingers. The thenar muscles are partially underdeveloped. In addition to the three phalangeal bones of the first radial finger the skeleton of the hand shows other abnormalities.

Adult↗
PubMed1979

Morphological and functional studies on the odontoid process of the human axis.

Studies on the morphology of the odontoid process by various methods strongly suggest a functional adaption of this bony element. With regard to the inclination of the dens axis and the varying position of its articular facets, a modified trabecular system can be observed. Photoelastic experiments confirm that these modifications are correlated with two specific kinds of mechanical stress. The straight odontoid process is only subjected to stress due to compression, but the dorsally inclined dens to bending stress. Based on the morphological and experimental findings, flexion and extension between the first and second vertebrae (in addition to rotation as the principle movement) are discussed.

Adaptation, Biological↗
PubMed1979

[Morphology of the adult human hyoid bone].

Investigations on 504 human hyoid bones show that there exist three main types, whose occurrence is, to a certain degree, sex-related. The junction between the body and the larger horns of the hyoid often is not ossified even in advanced age. Any determination of age on the basis of the extent of the corpus-cornu maius-ossification is most unreliable.

Adolescent↗
PubMed1979

[Injury pattern of the hyoid bone].

Based on the classification of hyoid bone into hyperbola-, parabola-, and horseshoe-shaped types, conditions were stimulated under planar and punctiform ventral force as well as in case of strangulation in photoelastic experiment. The results thus obtained were compared to those from former investigations in the field of bone tissue density. Hence, each hyoid type shows characteristic patterns of lesion of its own. The patterns of fractures and localizations which had been expected theoretically could be verified when compared to lesions that occurred in vital state. Then it turned out that horizontal fractures were typical of lesions of hyperbolic hyoid bones and vertical fractures of the cornu maius typical of lesions of parabolic hyoid bones.

Asphyxia↗
PubMed1979

[Biomechanical investigations on the aetiology of arthrosis of the first carpometacarpal joint (author's transl)].

Forty-eight carpometacarpal joints of the thumb (dissecting room material) were investigated roentgenologically and macroscopically. The localization of arthrotic lesions of the articular surfaces of the first metacarpal bone and the greater multangular bone support the view that arthrosis of the first carpometacarpal joint is due primarly to mechanical factors. The opposition movement of the thumb is combined with a pronating rotation of the first metacarpal bone. This rotation leads to an incongruity of the joint and in consequence to an extreme diminuition of the pressure transmitting area. Photoelastic experiments demonstrate that the point-like contact areas are subjected to an extremly high stress. The functional analysis of the tangential fiber layer in the articular cartilage shows that the first carpometacarpal joint is adapted only to movements typical for a saddle-shaped joint.

Adult↗
PubMed1978

Some observations on the development of the human hyoid bone.

Investigations on the human hyoid bone in several developmental stages reveal that with the chondrification of the mesenchymal blastema a typical interzone between the body and the greater cornua is formed. This disc of closely packed blastemal cells, distinct and broad in the earlier stages, is reduced in thickness in the course of further development. In fetuses between 5 and 6 months old and in newborns the formation of joint cavities can be seen in some cases. In other cases, however, a small transverse line of cells persists between the two cartilaginous elements. These findings are interpreted as different developmental stages of a diarthrosis generally formed between the corpus and the cornu majus. The fact that in the adult the lesser horn is connected directly to the cornu majus and not to the body is confirmed by the embryological investigations reported in this study.

Humans↗
PubMed1977

[Differentiation behavior of the mesodermal germinal sone of differently old pregastrulation stages of Ambystoma mexicanum. Cultivation of untreated and lithium-treated isolates].

Isolates from the dorsal, lateral and ventral area of the marginal zone are showing differentiation capacities already in the stage of early morula. The composition of the differentiation pattern alters: ecto- and mesodermal tissues are realized until the late morula. Beyond these, endodermal structures are visible with the stage of early blastula. After a mild Li treatment of the isolates the differentiation pattern of the marginal zone shows significant modifications. Ectodermal organs are registered to a lesser degree. Gut-structures are already visible within the stage of middle morula. The capacity for gut-differentiation is not restricted to only the lateral and ventral areas but is also observed in the dorsal region of the marginal zone. The results of experiments are discussed on the basis of Nieuwkoop's formation of the mesoderm in urodelean amphibians.

Ambystoma↗
PubMed1976

[Compression of the external carotid artery. An anatomical finding to Eagle's syndrome (author's transl)].

An anatomical finding to Eagle's styloid process-carotid artery syndrome is presented. The left external carotid artery of a 64-year-old male is compressed by an anomalous styloid process and by the tendon of the stylohyoid muscle. Symptoms caused by anomality of the styloid process are reported by means of literature. The histological examination of the vessel wall in the level, where it is compressed, reveals typical characteristics of early arteriosclerosis.

Aged↗