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Lumbrical Muscles Neural Branching Patterns: A Cadaveric Study With Potential Clinical Implications.Hand (New York, N.Y.) Sep 2022Lumbrical muscles originate in the palm from the 4 tendons of the flexor digitorum profundus and course distally along the radial side of the corresponding...
BACKGROUND
Lumbrical muscles originate in the palm from the 4 tendons of the flexor digitorum profundus and course distally along the radial side of the corresponding metacarpophalangeal joints, in front of the deep transverse metacarpal ligament. The first and second lumbrical muscles are typically innervated by the median nerve, and third and fourth by the ulnar nerve. A plethora of lumbrical muscle variants has been described, ranging from muscles' absence to reduction in their number or presence of accessory slips. The current cadaveric study highlights typical and variable neural supply of lumbrical muscles.
MATERIALS
Eight (3 right and 5 left) fresh frozen cadaveric hands of 3 males and 5 females of unknown age were dissected. From the palmar wrist crease, the median and ulnar nerve followed distally to their terminal branches. The ulnar nerve deep branch was dissected and lumbrical muscle innervation patterns were noted.
RESULTS
The frequency of typical innervations of lumbrical muscles is confirmed. The second lumbrical nerve had a double composition from both the median and ulnar nerves, in 12.5% of the hands. The thickest branch (1.38 mm) originated from the ulnar nerve and supplied the third lumbrical muscle, and the thinnest one (0.67 mm) from the ulnar nerve and supplied the fourth lumbrical muscle. In 54.5%, lumbrical nerve bifurcation was identified.
CONCLUSION
The complex innervation pattern and the peculiar anatomy of branching to different thirds of the muscle bellies are pointed out. These findings are important in dealing with complex and deep injuries in the palmar region, including transmetacarpal amputations.
Topics: Cadaver; Female; Hand; Humans; Male; Median Nerve; Muscle, Skeletal; Ulnar Nerve
PubMed: 33349041
DOI: 10.1177/1558944720963881 -
Biophysical Journal Feb 2021The microvascular networks in the body of vertebrates consist of the smallest vessels such as arterioles, capillaries, and venules. The flow of red blood cells (RBCs)...
The microvascular networks in the body of vertebrates consist of the smallest vessels such as arterioles, capillaries, and venules. The flow of red blood cells (RBCs) through these networks ensures the gas exchange in as well as the transport of nutrients to the tissues. Any alterations in this blood flow may have severe implications on the health state. Because the vessels in these networks obey dimensions similar to the diameter of RBCs, dynamic effects on the cellular scale play a key role. The steady progression in the numerical modeling of RBCs, even in complex networks, has led to novel findings in the field of hemodynamics, especially concerning the impact and the dynamics of lingering events when a cell meets a branch of the network. However, these results are yet to be matched by a detailed analysis of the lingering experiments in vivo. To quantify this lingering effect in in vivo experiments, this study analyzes branching vessels in the microvasculature of Syrian golden hamsters via intravital microscopy and the use of an implanted dorsal skinfold chamber. It also presents a detailed analysis of these lingering effects of cells at the apex of bifurcating vessels, affecting the temporal distribution of plasmatic zones of blood flow in the branches and even causing a partial blockage in severe cases.
Topics: Animals; Arterioles; Blood Flow Velocity; Capillaries; Cricetinae; Microcirculation; Microvessels
PubMed: 33359171
DOI: 10.1016/j.bpj.2020.12.012 -
Anatomical Record (Hoboken, N.J. : 2007) Apr 2019The hypoglossal or twelfth cranial nerve is the motor nerve to the extrinsic and intrinsic muscles of the tongue, and the superior root of the ansa cervicalis and the...
The hypoglossal or twelfth cranial nerve is the motor nerve to the extrinsic and intrinsic muscles of the tongue, and the superior root of the ansa cervicalis and the thyrohyoid and geniohyoid branches are delivered through the nerve. This study investigated the muscular branches of the hypoglossal nerve to clarify their spatial relationships with the muscles of the tongue and the neighboring structures. The muscles and the nerve were gross anatomically examined in 42 cadavers. The superior root and the thyrohyoid branch left the nerve near the occipital and lingual arteries, respectively. The extrinsic muscles consisted of some components, and the geniohyoid branch and the lingual branches arose on the hyoglossus. The ascending lingual branches formed a plexus on the anterior part of the hyoglossus and were divided into the proximal and distal groups. They supplied the two parts of the hyoglossus, the three bundles of the styloglossus and the superior and inferior longitudinal muscles and communicated with the lingual nerve. The descending lingual branches supplied the inferior part of the genioglossus, and the terminal branches gave intramuscular twigs to its main part and the transverse and vertical muscles. The findings indicated that the branching pattern of the hypoglossal nerve is characterized by the positional relationships to the components of the extrinsic muscles. The hyoid bone can be an effective marker to identify the branches and affected position if it was used in combination with the morphology of the extrinsic muscles, and the knowledge of their variations is also beneficial. Anat Rec, 302:558-567, 2019. © 2018 Wiley Periodicals, Inc.
Topics: Aged; Female; Humans; Hypoglossal Nerve; Lingual Nerve; Male; Muscles; Tongue
PubMed: 29659197
DOI: 10.1002/ar.23819 -
American Journal of Botany Sep 2019Hedera helix is a striking example of a plant with morphological traits and growth habits that vary between juvenile and adult phases. The present study focuses on its...
PREMISE
Hedera helix is a striking example of a plant with morphological traits and growth habits that vary between juvenile and adult phases. The present study focuses on its branching morphology and variations with age and change in growth habit, based on conspicuous stem-branch attachments previously described in related Araliaceae species.
METHODS
We decorticated and morphologically analyzed 300 samples of ramifications from prostrate, climbing and self-supporting axes of H. helix. For bending experiments, 103 specimens with the self-supporting growth habit were collected.
RESULTS
Ramifications of H. helix exhibited a so-called "finger-like" branching morphology with abaxial branch lobes and varying degrees of fusion of woody strands. Three categories of woody strand coalescence were defined. Biomechanical experiments in which the branches of stem-branch attachments were bent revealed two main modes of failure, breaking failure in (1) the attachment region and (2) the side branch.
CONCLUSIONS
Coalescence of woody strands in H. helix ramifications results from accumulation of secondary xylem with age, influenced by mechanical stimuli causing specific loading situations during different growth habits. Mechanical experiments showed the tendency toward failure in the side branch with increasing fusion of woody strands, affected by the diameter ratio of the side branch to the main axis. Of specific interest is the comparison of H. helix branching with tropical Araliaceae, which do not show the described coalescence of woody strands to this extent. Fracture toughness of self-supporting H. helix axes with merged stem-branch attachment regions are comparable to other self-supporting plant species, despite anatomical and ontogenetic differences.
Topics: Araliaceae; Biophysics; Hedera
PubMed: 31449336
DOI: 10.1002/ajb2.1341 -
Frontiers in Cellular Neuroscience 2022Segmental peripheral nerve injuries (PNI) are the most common cause of enduring nervous system dysfunction. The peripheral nervous system (PNS) has an extensive and...
Segmental peripheral nerve injuries (PNI) are the most common cause of enduring nervous system dysfunction. The peripheral nervous system (PNS) has an extensive and highly branching organization. While much is known about the factors that affect regeneration through sharp bisections and linear ablations of peripheral nerves, very little has been investigated or documented about PNIs that ablate branch points. Such injuries present additional complexity compared to linear segmental defects. This study compared outcomes following ablation of a branch point with branched grafts, specifically examining how graft source and orientation of the branched graft contributed to regeneration. The model system was Lewis rats that underwent a 2.5 cm ablation that started in the sciatic nerve trunk and included the peroneal/tibial branch point. Rats received grafts that were rat sciatic autograft, inbred sciatic allograft, and inbred femoral allograft, each of which was a branched graft of 2.5 cm. Allografts were obtained from Lewis rats, which is an inbred strain. Both branches of the sciatic grafts were mixed motor and sensory while the femoral grafts were smaller in diameter than sciatic grafts and one branch of the femoral graft is sensory and the other motor. All branched grafts were sutured into the defect in two orientations dictated by which branch in the graft was sutured to the tibial vs peroneal stumps in recipients. Outcome measures include compound muscle action potentials (CMAPs) and CatWalk gait analysis throughout the recovery period, with toluidine blue for intrinsic nerve morphometry and retrograde labeling conducted at the 36-week experimental end point. Results indicate that graft source and orientation does play a significant role earlier in the regenerative process but by 36 weeks all groups showed very similar indications of regeneration across multiple outcomes.
PubMed: 36451654
DOI: 10.3389/fncel.2022.1055490 -
Neurointervention Jul 2022This study aimed to validate the usefulness of parent artery complex coil protection for the treatment of wide-neck, side-branched, and ruptured aneurysms. A...
This study aimed to validate the usefulness of parent artery complex coil protection for the treatment of wide-neck, side-branched, and ruptured aneurysms. A microcatheter was first introduced into the aneurysmal sac, and another microcatheter was introduced into the parent artery or near the orifice of the branch artery. A framing coil was deployed partially from the first microcatheter, and a protection coil was deployed from the second microcatheter to prevent protrusion of the first framing coil to the parent artery and side branches. After the first framing coil insertion, the protection coil was withdrawn to confirm the stability of the framing coil and blood flow. The procedures with this technique were successful for 3 patients. Parent artery complex coil protection can be an effective and safe coil embolization technique for the preservation of parent and side branch arteries and an alternative method for emergent ruptured cases.
PubMed: 35719037
DOI: 10.5469/neuroint.2022.00136 -
Folia Morphologica 2021This study aims to revisit the anatomy of orbital segment of the third cranial nerve (CN III). The study also involved morphometric measurements of CN III muscular...
BACKGROUND
This study aims to revisit the anatomy of orbital segment of the third cranial nerve (CN III). The study also involved morphometric measurements of CN III muscular branches. Detailed description of observed anatomical variations and their incidence was also included. The study supplements earlier findings with detailed observations of the neuromuscular relations.
MATERIALS AND METHODS
The study was conducted on 52 orbits taken from 26 cadaveric heads (10 males and 16 females; Central European population).
RESULTS
Anatomical variations of the orbital segment of the CN III observed on the examined material involved both the superior and inferior branch of this nerve. The muscular branch innervating the levator palpebrae superioris muscle occasionally pierces the superior rectus muscle. The nerve to the inferior oblique muscle may pierce and innervate the inferior rectus muscle. In rare instances, duplication of the parasympathetic root of the ciliary ganglion may also occur. Among the muscular branches, the smallest diameter reached the branch to the levator palpebrae superioris muscle. Among the three muscular branches derived from the inferior branch of the CN III, the nerve to the inferior oblique was the longest one. Its length varied from 28.9 mm to 37.4 mm. The shortest was the muscular branch to the inferior rectus muscle. Its length varied from 0 mm (when muscular sub-branches arose directly from the nerve to the inferior oblique muscle) to 7.58 mm.
CONCLUSIONS
This study presented the characteristic of orbital segment of the CN III, including anatomical variations and morphometric measurements relevant to intraorbital procedures.
Topics: Female; Head; Humans; Male; Oculomotor Muscles; Oculomotor Nerve; Orbit
PubMed: 32073135
DOI: 10.5603/FM.a2020.0017 -
Annals of Botany Nov 2022Shoot ontogenesis in grasses follows a transition from a vegetative phase into a reproductive phase. Current studies provide insight into how branch and spikelet...
BACKGROUND AND AIMS
Shoot ontogenesis in grasses follows a transition from a vegetative phase into a reproductive phase. Current studies provide insight into how branch and spikelet formation occur during the reproductive phase. However, these studies do not explain all the complex diversity of grass inflorescence forms and are mostly focused on model grasses. Moreover, truncated inflorescences of the non-model grass genus Urochloa (Panicoideae) with formation of primary branches have basipetal initiation of branches. Bouteloua species (Chloridoideae) are non-model grasses that form truncated inflorescences of primary branches with apical vestiges of uncertain homology at the tips of branching events and sterile florets above the lowermost fertile floret. Sterile florets are reduced to rudimentary lemmas composed of three large awns diverging from an awn column. Conflict about the awn column identity of this rudimentary lemma is often addressed in species descriptions of this genus. We test if Bouteloua species can display basipetal initiation of branches and explore the identity of vestiges and the awn column of rudimentary lemmas.
METHODS
We surveyed the inflorescence ontogeny and branch/awn anatomy of Bouteloua species and compared results with recent ontogenetic studies of chloridoids.
KEY RESULTS
Bouteloua arizonica has florets with basipetal maturation. Branches display basipetal branch initiation and maturation. Branch vestiges are formed laterally by meristems during early branching events. The spikelet meristem forms the awn column of rudimentary lemmas. Vestiges and sterile floret awns have anatomical similarities to C4 leaves.
CONCLUSIONS
Basipetal initiation of branches is a novel feature for Chloridoideae grasses. Branch vestiges are novel vegetative grass structures. Sterile floret awn columns are likely to be extensions of the rachilla.
Topics: Poaceae; Meristem; Inflorescence; Plant Leaves; Plant Proteins
PubMed: 35961673
DOI: 10.1093/aob/mcac104 -
Plants (Basel, Switzerland) Oct 2022Understanding the Sichuan potted landscapes, one of the five types of traditional Chinese potted landscapes, is important for exploring the development of Sichuan...
Understanding the Sichuan potted landscapes, one of the five types of traditional Chinese potted landscapes, is important for exploring the development of Sichuan landscape architecture in Southwest China. In this study, we analyzed the shape and aesthetic characteristics of the traditional regular bonsai of the Sichuan style according to trunk features, branch patterns, tree shape, branch arrangement, and branch and plate numbers. Studies have shown that the flat-branch-type branch plate slopes downward and the bottom rises, and the number of branch plates is 2n + 1 (where n is the number of layers of the branch plate, n > 4), which is a proportional sequence. The ratio of the main pile height to the footplate is approximately 1.5:1−2:1, the pot:footplate ratio is <1:1, and the maximum bend:trunk ratio is <1:2. There were extremely significant differences between the length of the foot plate and its adjacent branch and plate length and the distance between the branch and plate. Interestingly, the rolling branch-type plants are characterized by vertical curved branches, oblique curved branches, and curved branches, reflecting the beauty of harmony and symmetry. Overall, the regular-style Sichuan tree potted landscape is mainly characterized by the beauty of rhythm and symmetry.
PubMed: 36297808
DOI: 10.3390/plants11202784