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Biomedical subjects

R Reimann

Publications and source records attributed to R Reimann.

At least 55 records · Page 3Linked to original sources
PubMed1981

[Variable extensor apparatus of the small toe. Opposing muscle groups in competition for extensor function of the fifth involutional metacarpal ray of the lower extremity].

In 200 human feet 37 differently formed extensor apparatus of the fifth toe were found. This great variability is obviously caused by several independent phylogenetic processes related with the acquisition of the upright gait. In primitive tetrapods three extensor muscles exist for the toes, whereas in mammals two of these muscles are in a rivalling but not vicarious relationship: While the long extensor muscles (M. extensor digitorum longus) remain in all trinomial toes, the fibular extensor muscles (Mm. peronaei digitorum) are laterally displaced by the short extensor muscles (M. extensor digitorum brevis). Although in man the fibular extensor muscles are largely suppressed, the short extensor muscles hardly often reach the fifth toe because this involuting toe is only of limited motor importance with regard to the entire function of the human foot. The ontogenetic involution of the fibular extensor muscles - which in the human embryo are regularly developed as M. peronaeus digiti IV and M. peronaeus digiti V - usually remains at an intermediate stage, i.e. a tendon of the M. peronaeus brevis branches off towards the dorsum pedis. In the anthropoids this involution is associated with the evolution and acquisition of the M. peronaeus III. To obtain strong effects for pronation and dorsiflexion necessary for the upright gait the M. peronaeus III inserts at the stable metatarsus instead of the mobile fifth toe by which an earlier phylogenetic stage is achieved. In the metatarsus the peronaeus tertius muscle inserts in different positions with regard to the remnants of the fibular extensor muscles. In this paper the two processes - both involution of the peronaei digitorum muscles and evolution of the peronaeus tertius muscle - are illustrated by several intermediate links found in dissected feet.

Biological Evolution↗
PubMed1980

Viral pesticides : biohazard evaluation on the cytogenetic level.

Promising agents for integrated pest control are naturally occuring insect pathogenic viruses that belong to the group of baculoviruses. We have performed experiments using mammalian cells from different species in vivo and in vitro to test a possible effect of baculoviruses on chromosome aberration rates and sister chromatid exchanges. No cytogenetic effects were found.

Animals↗
PubMed1980

[The basic human thumb joint--an egg-shaped joint].

The metacarpophalangeal joint of the human thumb (Articulatio metacarpophalangea pollicis) is an ellipsoidal (condyloid) joint. The head of the first metacarpal bone is shaped like a spindle polled at either end. Its form relevant to the mobility is determined by the correlation of two flexures, expressed by the quotient R/r, where R = semi-diameter of the radio-ulnar flexure and r = semi-diameter of the dorso-palmar flexure in the middle of the head. Only the substantial kind of motion (flexion-extension) maintains the perfect contiguity of the articular surfaces. Owing to the deformability of the articular cartilage, the actual littleness of the articular surfaces as well as the relative smallness of the cavity with respect to the head permits both transverse motions (adduction-abduction) and axial motions (rotation inward and outward). The amplitude of the transverse motion unexpectedly does not correlate to the intensity of the radio-ulnar flexure of the head.

Finger Joint↗
PubMed1980

[Compensatory movements of the fibula necessitated by the wedge shape of the trochlea tali].

The lateral articular facet of the talus (Facies malleolaris lateralis) is slanting and irregularly shaped; therefore, the fibula shows compensative motions in transverse, sagittal, vertical and rotational directions when the ankle joint is moved. There are contradictory statements concerning the course of this compensative rotation, because the fibula shows individually different reactions. The fibula is not rotated during dorsiflexion in nearly 25% of legs; approximately one half of the remaining fibulae is rotated outward, the other half inward. The matter of fact is not surprising, when the shape of the lateral articular facet is inspected exactly: it resembles a flat saddle, the anterior part of which is screw-shaped. The fibula rotates outward during dorsiflexion, if the furrow of this screw-shaped area increases forward; it rotates inward, if the furrow diminishes forward; and it does not rotate at all, if the furrow is constant.

Ankle Joint↗
PubMed1979

[Margins and torsion of the human fibula].

The borders and ridges of the fibula show a difficult aspect caused by the bone-forming musculature. These structures are an occasion for misunderstanding and mistaken denominations, which even had a noticeable effect on the PNA. Two thirds of all human fibulae exhibit a clearly prominent 'crista musculi tibialia posterioris', giving tendinuous attachment to the tibialis posterior muscle. In diagnosis of borders this crista may lead to errors, because it branches off from the interosseous border underneath the upper fourth of the fibula and reaches the medial crest in the middle of the bone. Most of the borders of the fibula show a twisted course corresponding to the direction of the shaping musculature and effecting a fictitious torsion of the shaft. The proper torsion of the fibula, however, is substantiated by the difference between the absolute torsion (= twist of the two ends of the bone) and the accompanying torsion (= twist enforced by the torsion of the tibia).

Biomechanical Phenomena↗