RESUMO
A persistent median artery is a rare anomaly. It accompanies the median nerve along its course in the forearm and is of variable origin. It is associated with other local anatomical variations and may contribute significantly towards formation of the superficial palmar arch. In embryos, it is responsible mainly for the blood supply to the hand. The objective of this study was to research the frequency, type (forearm or palmar) and origin of the median artery in fetuses, correlating its presence with sex and body side. Red-colored latex was injected into 32 brachial arteries of human fetuses until its arrival in the hand could be seen. Twenty-four hours after the injection, the median arteries were dissected without the aid of optical instruments. Among the 32 forearms dissected, the median artery was present in 81.25 % (26) of the cases, and it was found more frequently in females and on the left side. Regarding origin, most of the median arteries originated in the common interosseous artery (38.5 %) and anterior interosseous artery (34.6 %). The mean length of the median arteries was 21.1 mm for the palmar type and 19.8 mm for the forearm type. The median artery has a high rate of persistence. It is important to be aware of this anatomical variation, since its presence may give rise to difficulties during routine surgical procedures on the wrist. Its presence may cause serious functional complications in the carpal tunnel, anterior interosseous nerve, round pronator syndromes, and ischemia of the hand.
Assuntos
Variação Anatômica , Artéria Braquial/anormalidades , Artéria Braquial/anatomia & histologia , Feto/anatomia & histologia , Antebraço/irrigação sanguínea , Antebraço/embriologia , Nervo Mediano/irrigação sanguínea , Síndrome do Túnel Carpal/etiologia , Feminino , Antebraço/inervação , Humanos , MasculinoRESUMO
Although the majority of peripheral-nerve regeneration studies are carried out on the sciatic nerve, lesions of the upper extremities are more common in humans and usually lead to significant physical disabilities. The present study was driven by the hypothesis that a combination of strategies, namely grafts of mesenchymal stem cells (MSC) and resorbable polycaprolactone (PCL) conduits would improve median-nerve regeneration after transection. Mouse median nerves were transected and sutured to PCL tubes that were filled with either green fluorescent protein (GFP(+)) MSC in DMEM or with DMEM alone. During the post-operative period, animals were tested weekly for flexor digitorum muscle function by means of the grasping test. After 8 weeks, the proximal and middle portions of the PCL tube and the regenerating nerves were harvested and processed for light and electron microscopy. The flexor digitorum muscle was weighed and subjected to biochemical analysis for creatine phosphokinase (CK) levels. Scanning electron microscopy of the PCL tube 8 weeks after implantation showed clear signs of wall disintegration. MSC-treated animals showed significantly larger numbers of myelinated and unmyelinated nerve fibers and blood vessels compared with DMEM-treated animals. The flexor digitorum muscle CK levels were significantly higher in the MSC-treated animals, but muscle weight values did not differ between the groups. Compared with the DMEM-treated group, MSC-treated animals showed, by the grasping test, improved functional performance throughout the period analyzed. Immunofluorescence for S-100 and GFP showed, in a few cases, double-labeled cells, suggesting that transplanted cells may occasionally transdifferentiate into Schwann cells. Our data demonstrate that the polycaprolactone conduit filled with MSC is capable of significantly improving the median-nerve regeneration after a traumatic lesion.
Assuntos
Creatina Quinase/metabolismo , Nervo Mediano/fisiopatologia , Transplante de Células-Tronco Mesenquimais , Músculo Esquelético/fisiopatologia , Poliésteres , Animais , Diferenciação Celular , Membro Anterior , Nervo Mediano/irrigação sanguínea , Nervo Mediano/lesões , Nervo Mediano/ultraestrutura , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/enzimologia , Músculo Esquelético/inervação , Fibras Nervosas Mielinizadas/ultraestrutura , Regeneração Nervosa , Células de Schwann/citologiaRESUMO
An unusual case of thrombosis of a persistent median artery as a cause of acute carpal tunnel syndrome is reported. The sudden onset of numbness in the median nerve distribution and pain in the fingers were the main symptoms. The embryonic development of the median nerve vascular supply and the reported incidence of persistent median artery are reviewed.
Assuntos
Síndrome do Túnel Carpal/etiologia , Mãos/irrigação sanguínea , Trombose/complicações , Adulto , Artérias/anormalidades , Artérias/cirurgia , Síndrome do Túnel Carpal/cirurgia , Feminino , Humanos , Nervo Mediano/irrigação sanguínea , Trombose/cirurgiaRESUMO
An ususual case of thrombosis of a persistent median artery as a cause of acute carpal tunnel syndrome is reported. The sudden onset of numbness in the median nerve distribution and pain in the fingers were main symptoms. The embryonic development of the median nerve vascular supply and the reported incidence of persistent median artery are reported(AU)
Assuntos
Relatos de Casos , Humanos , Feminino , Adulto , Síndrome do Túnel Carpal/etiologia , Trombose/complicações , Mãos/irrigação sanguínea , Nervo Mediano/irrigação sanguíneaRESUMO
An ususual case of thrombosis of a persistent median artery as a cause of acute carpal tunnel syndrome is reported. The sudden onset of numbness in the median nerve distribution and pain in the fingers were main symptoms. The embryonic development of the median nerve vascular supply and the reported incidence of persistent median artery are reported