Estudo da inervação e vascularização do membro torácico de Columba livia / Study of innervation and vascularization of the thoracic limb of Columba livia

No estudo referente aos territórios vásculo-nervos os em membro torácico de Pombos (Columba livia) foram utilizados 10 animais. Após a retirada de penas e pele, procedeu-se à identificação dos nervos no membro torácico direito, iniciando-se pela aplicação de compressas de ácido acético glacial 3% e dissecação de cada ramo do plexo braquial e seus músculos de inervação. Para a identificação dos territórios vasculares realizou-se a abertura da cavidade toraco abdominal, canulação do coração seguida de injeção de látex sintético via ventrículo esquerdo, dissecação dos vasos, medição e confecção de esquemas dos resultados. O plexo braquial é composto pelos nervos axilar, radial, peitoral e medianoulnar, em que os dois primeiros são responsáveis pela inervação da musculatura extensora, enquanto os dois últimos responsabilizam-se pela motricidade da musculatura flexora. Ainda pode ser observado um plexo acessório. O tronco braquiocefálico surge da Aorta ascendente, sendo encontrado um tronco direito e um esquerdo, emitindo as artérias carótida comum e subclávia como troncos principais. Destes surgem vasos que irrigam a cabeça, a região cervical e os membros torácicos. Em todas as aves observou-se uma constância na irrigação e inervação da musculatura, articulações e ossos do membro torácico, onde se pode presumir que existe uma constante na delimitação dos territórios vásculo-nervosos.

In the referring study of the vasculo-nervous territories in the thoracic of pigeons (Columba livia) 10 animals had been used. After the withdrawal of feathers and skin, proceeded the identification from the nerves in the right thoracic limb, initiating for the application of compresses of glacial acetic acid solution 3% and dissection of each branch of brachial plexus and its muscles of innervation. For the identification of the vascular territories it was become fulfilled opening of the toracoabdominal cavity, followed of synthetic latex injection saw ventricle left, dissection of the vases, measurement and confection of projects of the results. The brachial plexus is composed for the axillary, radial, pectoral and median-ulnar nerves, where the two first ones are responsible for the innervation of the extensor musculature, while the two last ones make responsible for the movements of the flexor musculature. And still can be observed one accessory plexus.The brachiocephalic trunk appears of the ascending aorta, being found a trunk right and a left, emitting the commom carotid and subclavies arteries as main trunk. Of the vases appear that irrigate the head, the cervical region and the thoracic limbs. In all birds was observed constancy in the irrigation and innervation of the musculature, joints and bones of the thoracic limb, where if it we can presume that existes a constant in the delimitation of the territories vasculo-nervous

Neuronal structure of microvascular transplants with and without neuronal anastomosis.

OBJECTIVE: Latissimus dorsi transplants have little neuronal regenerative capacity without neuronal anastomosis. Histologic differences between transplants with and without neuronal anastomosis and 2 distinct types of neurosurgical reanastomosis are highlighted in this study. PATIENTS AND METHODS: Fifty-four patients with squamous cell carcinomas of the oral cavity (T4) were treated by tumor resection and homolateral neck dissection. The defect was covered with a microvascular latissimus dorsi transplant. In 15 patients, no neuronal anastomoses were performed. In 21 patients, the thoracodorsal nerves were used for microneurosurgical reanastomosis, whereas in 18 patients, the cutaneous branches of the intercostal nerves were used for microneurosurgical reanastomosis. The transplant was examined during surgery and 9 months after surgery by means of a histologic examination of a biopsy specimen. The number of fascicles, the degree of fibrosis, and the myelination were examined. Furthermore, a neurosensory examination was performed 9 months after surgery. RESULTS: Overall, our patients had an average of 12.1 fascicles during surgery. After surgery, patients without neuronal anastomosis showed an average of 4.9 fascicles, patients with nerve anastomosis to the cutaneous branches of the intercostal nerve showed an average of 6.2 fascicles, and patients with anastomosis to the thoracodorsal nerve showed an average of 9.6 fascicles. In cases of nerve anastomosis, a lesser degree of fibrosis was found, together with good myelinization. The clinical examination showed the best neurosensory function in the transplants with anastomosis to the thoracodorsal nerve and the worst function in those without neuronal anastomosis. CONCLUSION: Neuronal reanastomosis led to more surviving neuronal structures in the postoperative histologic specimen. The highest density of fascicles was found in the well vascularized thoracodorsal nerve. The neurosensory function agrees with the histologic result.

Anatomic basis of vascularized nerve graft using the long thoracic nerve.

Vascularized nerve transplants can lead to satisfactory functional reconstruction for nerve defects. These include defects following traumatic nerve severance, iatrogenic severance during tumour resection and extensive defects in poorly vascularized transplant sites. No previous description of the long thoracic nerve as a vascularized nerve graft is available. The aim of this study was to demonstrate the anatomic and initial clinical application of such a graft. The long thoracic nerve was dissected in 84 cases to examine its length, diameter, ramification and type of perfusion. On removal of the nerve, adequate perfusion through the thoracodorsal artery and a constant anatomic course with minimal loss of function were found. The long thoracic nerve is accessible anatomically, easily dissected and removed. This may be carried out together with the thoracodorsal vein and artery and even with a pedicled myocutaneous latissimus dorsi transplant, an osseo-myocutaneous scapulo-latissimus dorsi transplant or an osseous scapular transplant. The long thoracic nerve transplant can be employed for extensive facial defects together with simultaneous osseous and myocutaneous transplants of the shoulder region.

Effect of adaptive pulse train duration on latissimus dorsi blood flow.

Blood flow, intramuscular pressure, and stroke work of the trained latissimus dorsi muscle (LD) were measured during electrical stimulation at contraction rates between 20 and 160/min using pulse trains of 2 to 6 pulses in length. Epimysial electrodes and intramuscular pressure sensors were implanted in the LD of 5 dogs. The muscle remained in situ. After 12 weeks of a progressive training protocol, LD blood flow (BF) was measured using an ultrasonic flow probe and work (SW) was determined from the measured force and shortening. For pulse trains of 2 or 3 pulses, BF increased with rate, and SW was maintained at all rates. For 4 pulses, BF and SW decreased when the contraction rate exceeded 120/min. SW decreased above 100/min and 80/min for 5 and 6 pulses, respectively. An upper rate limit dependent upon the pulse train duration exists above which BF and SW decline. Exceeding these upper rate limits should be avoided in cardiomyoplasty. Excessive stimulation rates could be detrimental to the muscle by creating a metabolic insufficiency or ischemia. The cardiac assistance benefit is compromised as SW declines during high contraction rates of long pulse train duration.