Axillary nerve neurotization by a triceps motor branch: comparison between axillary and posterior arm approaches / Neurotização do nervo axilar por um ramo do tríceps: comparação entre acesso axilar e posterior

ABSTRACT Objectives: This study is aimed at comparing the functional outcome of axillary nerve neurotization by a triceps motor branch through the axillary approach and posterior arm approach. Methods: The study included 27 patients with post-traumatic brachial plexus injury treated with axillary nerve neurotization by a triceps motor branch for functional recovery of shoulder abduction and external rotation. The patients were retrospectively evaluated and two groups were identified, one with 13 patients undergoing axillary nerve neurotization by an axillary approach and the second with 14 patients using the posterior arm approach. Patients underwent assessment of muscle strength using the scale recommended by the British Medical Research Council, preoperatively and 18 months postoperatively, with useful function recovery considered as grade M3 or greater. Results: In the axillary approach group, 76.9% of patients achieved useful abduction function recovery and 69.2% achieved useful external rotation function recovery. In the group with posterior arm approach, 71.4% of patients achieved useful abduction function recovery and 50% achieved useful external rotation function recovery. The difference between the two groups was not statistically significant (p = 1.000 for the British Medical Research Council abduction scale and p = 0.440 for external rotation). Conclusion: According to the British Medical Research Council grading, axillary nerve neurotization with a triceps motor branch using axillary approach or posterior arm approach shows no statistical differences.

RESUMO Objetivos: Comparar o resultado funcional da neurotização do nervo axilar por um ramo motor do tríceps através do acesso axilar e do acesso posterior. Métodos: Foram incluídos no estudo 27 pacientes com lesão pós-traumática de plexo braquial submetidos à neurotização do nervo axilar por um ramo motor do tríceps para recuperação funcional do ombro de 2010 a 2014. Os pacientes foram avaliados e dois grupos foram identificados, um com 13 pacientes submetidos a neurotização do nervo axilar por um acesso axilar e o segundo com 14 pacientes nos quais foi usada a via de acesso posterior. Os pacientes foram submetidos a avaliação da força muscular com a escala preconizada pelo British Medical Research Council (BMRC) no pré-operatório e com 18 meses de pós-operatório, foi considerada força motora efetiva graduação M3 ou maior. Resultados: No grupo que fez o acesso axilar, 76,9% dos pacientes obtiveram força motora efetiva de abdução e 69,2% de rotação externa. Já no grupo com acesso posterior, 71,4% dos pacientes conseguiram força motora efetiva de abdução e 50% de rotação externa. A diferença entre os dois grupos não foi estatisticamente significante (p = 1,000 para escala BMRC de abdução e p = 0,440 para rotação externa). Conclusão: Na avaliação da graduação de força na escala BRMC, o uso do acesso axilar para neurotização de um ramo motor do tríceps para o nervo axilar não apresenta diferenças estatísticas em relação ao uso do acesso posterior.

Axillary nerve neurotization by a triceps motor branch: comparison between axillary and posterior arm approaches.

OBJECTIVES: This study is aimed at comparing the functional outcome of axillary nerve neurotization by a triceps motor branch through the axillary approach and posterior arm approach. METHODS: The study included 27 patients with post-traumatic brachial plexus injury treated with axillary nerve neurotization by a triceps motor branch for functional recovery of shoulder abduction and external rotation. The patients were retrospectively evaluated and two groups were identified, one with 13 patients undergoing axillary nerve neurotization by an axillary approach and the second with 14 patients using the posterior arm approach. Patients underwent assessment of muscle strength using the scale recommended by the British Medical Research Council, preoperatively and 18 months postoperatively, with useful function recovery considered as grade M3 or greater. RESULTS: In the axillary approach group, 76.9% of patients achieved useful abduction function recovery and 69.2% achieved useful external rotation function recovery. In the group with posterior arm approach, 71.4% of patients achieved useful abduction function recovery and 50% achieved useful external rotation function recovery. The difference between the two groups was not statistically significant (p = 1.000 for the British Medical Research Council abduction scale and p = 0.440 for external rotation). CONCLUSION: According to the British Medical Research Council grading, axillary nerve neurotization with a triceps motor branch using axillary approach or posterior arm approach shows no statistical differences.

OBJETIVOS: Comparar o resultado funcional da neurotização do nervo axilar por um ramo motor do tríceps através do acesso axilar e do acesso posterior. MÉTODOS: Foram incluídos no estudo 27 pacientes com lesão pós-traumática de plexo braquial submetidos à neurotização do nervo axilar por um ramo motor do tríceps para recuperação funcional do ombro de 2010 a 2014. Os pacientes foram avaliados e dois grupos foram identificados, um com 13 pacientes submetidos a neurotização do nervo axilar por um acesso axilar e o segundo com 14 pacientes nos quais foi usada a via de acesso posterior. Os pacientes foram submetidos a avaliação da força muscular com a escala preconizada pelo British Medical Research Council no pré-operatório e com 18 meses de pós-operatório, foi considerada força motora efetiva graduação M3 ou maior. RESULTADOS: No grupo que fez o acesso axilar, 76,9% dos pacientes obtiveram força motora efetiva de abdução e 69,2% de rotação externa. Já no grupo com acesso posterior, 71,4% dos pacientes conseguiram força motora efetiva de abdução e 50% de rotação externa. A diferença entre os dois grupos não foi estatisticamente significante (p = 1,000 para escala British Medical Research Council de abdução e p = 0,440 para rotação externa). CONCLUSÃO: Na avaliação da graduação de força na escala British Medical Research Council, o uso do acesso axilar para neurotização de um ramo motor do tríceps para o nervo axilar não apresenta diferenças estatísticas em relação ao uso do acesso posterior.

High-Definition Video System for Peripheral Neurorrhaphy in Rats.

BACKGROUND: Although all microsurgeries are based on the use of surgical microscopes, several alternative magnification systems have shown promising results. Improvements in image quality facilitated the use of video systems in microsurgeries with safety and accuracy. The aim of this study was to evaluate the use of a low-cost, video-assisted magnification system in peripheral neurorrhaphy in rats. METHODS: Twenty Wistar rats were randomly divided into 2 matched groups according to the magnification system used: the microscope group, with neurorrhaphy performed under a microscope with an image magnification of 40×; and the video system group, with the procedures performed under a video system composed of a high-definition Sony camcorder DCR-SR42 set to 52× magnification, macro lenses, 42-inch television, and a digital HDMI cable. We analyzed weight, nerve caliber, total surgery time, neurorrhaphy time, number of stitches, and number of axons in both ends (proximal and distal). RESULTS: There were no significant differences between groups in weight, nerve caliber, or number of stitches. Neurorrhaphy under the video system took longer (video: 5.60 minutes; microscope: 3.20 minutes; P < .05). Number of axons was similar between groups, both in proximal and distal stumps. CONCLUSION: It is possible to perform a peripheral neurorrhaphy in rats through video system magnification, but with a longer surgical time.

A Low-Cost High-Definition Video System for Microsurgical Hindlimb Replantation in Rats.

Background The surgical microscope is still essential for microsurgery, but several alternatives that show promising results are currently under development, such as endoscopes and laparoscopes with video systems; however, as yet, these have only been used for arterial anastomoses. The aim of this study was to evaluate the use of a low-cost video-assisted magnification system in replantation of the hindlimbs of rats. Methods Thirty Wistar rats were randomly divided into two matched groups according to the magnification system used: the microscope group, with hindlimb replantation performed under a microscope with an image magnification of 40× and the video group, with the procedures performed under a video system composed of a high-definition camcorder, macrolenses, a 42-in television, and a digital HDMI cable. The camera was set to 50× magnification. We analyzed weight, arterial and venous caliber, total surgery time, arterial and venous anastomosis time, patency immediately and 7 days postoperatively, the number of stitches, and survival rate. Results There were no significant differences between the groups in weight, arterial or venous caliber, or the number of stitches. Replantation under the video system took longer (p < 0.05). Patency rates were similar between groups, both immediately and 7 days postoperatively. Conclusion It is possible to perform a hindlimb replantation in rats through video system magnification, with a satisfactory success rate comparable with that for procedures performed under surgical microscopes.

Avaliação do metabolismo de etanol em ratos expostos a diferentes temperaturas / Evaluation of the ethanol metabolism in rats undergone different temperatures

Objetivo: avaliar o metabolismo do etanol em diferentes temperaturas. Método: foram utilizados 11ratos mantidos à temperatura corporal de 30ºC (Grupo Frio) e posteriormente a 39,5ºC (Grupo Quente).O etanol foi administrado aos animais etanol na dose de 3g.kg-¹. Foi então realizada punção cardíaca comcoleta do material para determinação da concentração sanguínea do etanol. Resultados: no Grupo Frio asconcentrações séricas de etanol foram aproximadamente 22% menores que no Grupo Quente. Entretanto,resultados divergentes foram encontrados na literatura, sendo estes também ainda insuficientes para umadefinição final a respeito do efeito da temperatura no metabolismo do etanol. Conclusão: observou-seque ratos submetidos a temperaturas ambiente mais baixas registraram menores níveis séricos de etanol,após administração via oral, em comparação com animais submetidos a maiores temperaturas. Entretanto,mais estudos são ainda necessários para elucidar esta questão e suas implicações práticas no estudo dometabolismo do etanol

Introduction: overall, the ethanol causes 3,2% of deaths or 1,8 million deaths and, per year, represents 4,0% of alldeseases, mainly in countries in development. Studies of metabolism in people who live in different geographicregions have revealed metabolic rates 10% to 20% lower in tropical regions than in artic regions. Many experimentalresearchs, however, have revealed lower seric ethanol rates in rats undergone high temperatures. Objective: evaluatethe ethanol metabolism in rats undergone different temperatures. Method: for that, it was used 11 rats exposed to30oC and after to 39,5oC. The ethanol was given through gavage in the dose of 3g.Kg -¹. Then, a cardiac puction andthe collect of the material was performed in order to determinate the blood ethanol concentration. The results weresubmitted to statistic tests. Results: it was found that in the Cold Group, the ethanol concentrations wereapproximately 22% lower than in Heat Group. However, divergent results were found in literature, but they are stillinsufficient for a final definition about the temperature effect in ethanol metabolism. Conclusion: in rats undergonelower temperatures the seric concentration of ethanol is lower than in rats under higher temperatures. Thus, it wasconcluded that more studies are still necessary to clarify this question.