ABSTRACT Introduction: Reconstructive head and neck surgery is a challenge for the plastic surgeon and requires a large technical arsenal, in which microsurgery plays an essential role. The objective to retrospectively analyze microsurgical head and neck reconstruction performed at the Pontifical Catholic University of Campinas over a period of 2 years. Methods: The medical charts of patients who underwent microsurgical reconstruction after head and neck surgery between June 2014 and October 2016 were reviewed to determine which flap was used, the length of the vascular pedicle, recipient vessels, microvascular anastomoses, surgical time, length of hospital stay, complications, and success rate. Results: Thirty microsurgical reconstructions were performed using 3 types of flaps: anterolateral thigh (n = 15), antebrachial radial (n = 8), and fibula (n = 7). Recipient vessels: facial artery (70%) and facial vein (50%), as 92.4% of microvascular anastomoses were end-to-end. The average operative time was 10.1 hours. The average length of hospital stay was 10.7 days. Two flaps were lost due to arterial thrombosis, resulting in a success rate of 93.3%. Conclusions: The microsurgical reconstructions were effective for the repair of complex defects as well as to partially restore the shape and function of the affected tissues. Complications were observed in less than 50% of the cases, although these presented with significant morbidity. The success rate was similar to that reported by major centers of reconstructive microsurgery. The learning curve is long, although it tends to improve with staff training and the acquisition of experience over time.

RESUMO Introdução: Cirurgia reconstrutiva em cabeça e pescoço representa desafio ao cirurgião plástico e requer amplo arsenal técnico, no qual a microcirurgia figura papel essencial. O objetivo é analisar retrospectivamente as reconstruções microcirúrgicas em cabeça e pescoço realizadas na Pontifícia Universidade Católica de Campinas no período de dois anos. Métodos: Pacientes submetidos à reconstrução microcirúrgica após cirurgia de cabeça e pescoço, entre junho de 2014 e outubro de 2016, tiveram seus prontuários revisados para avaliação do retalho utilizado, comprimento do pedículo vascular, vasos receptores, anastomoses microvasculares, duração da cirurgia, tempo de internação, complicações e índice de sucesso. Resultados: Foram realizadas 30 reconstruções microcirúrgicas com três tipos de retalhos: anterolateral da coxa (n = 15), antebraquial radial (n = 8) e fíbula (n = 7). Vasos receptores: artéria facial (70%) e veia facial (50%), sendo que 92,4% das anastomoses microvasculares foram término-terminais. As cirurgias duraram, em média, 10,1 horas. O tempo médio de internação hospitalar foi de 10,7 dias. Houve perda de dois retalhos por trombose arterial, levando à taxa de sucesso de 93,3%. Conclusões: As reconstruções microcirúrgicas analisadas foram eficazes na reparação dos defeitos complexos, restaurando parcialmente forma e função dos tecidos acometidos. Foram observadas complicações em menos da metade dos casos, porém com morbidade elevada. O índice de sucesso foi semelhante ao de grandes centros de microcirurgia reconstrutiva. A curva de aprendizado é longa, mas tende a melhorar com o treinamento da equipe e aquisição de experiência ao longo do tempo.

ABSTRACT PURPOSE: To evaluate a new model of intraoperative electromyographic (EMG) assessment of the tibial and fibular nerves, and its respectives motor units in rats. METHODS: Eight Wistar rats underwent intraoperative EMG on both hind limbs at two different moments: week 0 and week 12. Supramaximal electrical stimulation applied on sciatic nerve, and compound muscle action potential recorded on the gastrocnemius muscle (GM) and the extensor digitorum longus muscle (EDLM) through electrodes at specifics points. Motor function assessment was performaced through Walking Track Test. RESULTS: Exposing the muscles and nerves for examination did not alter tibial (p=0.918) or fibular (p=0.877) function between the evaluation moments. Electromyography of the GM, innervated by the tibial nerve, revealed similar amplitude (p=0.069) and latency (p=0.256) at week 0 and at 12 weeks, creating a standard of normality. Meanwhile, electromyography of the EDLM, innervated by the fibular nerve, showed significant differences between the amplitudes (p=0.003) and latencies (p=0.021) at the two different moments of observation. CONCLUSION: Intraoperative electromyography determined and quantified gastrocnemius muscle motor unit integrity, innervated by tibial nerve. Although this study was not useful to, objectively, assess extensor digitorum longus muscle motor unit, innervated by fibular nerve.

PURPOSE: To compare sciatic nerve regeneration between non-diabetic (control) and streptozotocin-induced diabetic Wistar rats. METHODS:Four subgroups were evaluated. CN: Non-diabetic rats submitted to neurorrhaphy (n=9); DN: Diabetic rats submitted to neurorrhaphy (n=9); CG: Non-diabetic rats submitted to nerve grafting (n=10); DG: Diabetic rats submitted to nerve grafting (n=9). The nerve regeneration was evaluated by walking track analysis (sciatic functional index), electrophysiological test, histomorphometric analysis and triceps surae muscle weight. RESULTS:At 60 days post-surgery, functional recovery of DN was similar to that of the non-diabetic rats (CN, CG), but DG didn't achieve the same. Evoked potential amplitudes showed no statistically significant differences among subgroups. Triceps surae muscle was heavier in CN. No statistically significant differences were observed between the control and diabetes subgroups with respect to histomorphometric analysis. CONCLUSION: After 60 days, DN had a functionally similar recovery to that of the control animals, whereas nerve grafting in diabetic rats didn't allow the same. The muscle atrophy was lower in CN. In the rest of evaluations, as electrophysiological and histomorphometric, diabetic rats were not different from control ones.

A formação do hematoma intraneural com comprometimento de nervos periféricos pode ocorrer após trauma ou coagulopatias. O tratamento expectante ou abordagem cirúrgica descompressiva ainda não estão definidos. Foram estudados 40 ratos da raça Wistar divididos em 4 grupos. No grupo A realizou-se injeção intraneural de 0,2 ml de sangue autógeno no nervo ciático direito. No grupo B, após produção do hematoma, fez-se descompressão imediata com epineurotomia longitudinal. No grupo D realizamos liberação imediata do hematoma com neurólise interfascicular. No grupo C (CONTROLE) apenas realizou-se a exposição do nervo ciático sem formação de hematoma. A avaliação da função nervosa foi feita com o Índice de Função Ciática de Bain-Mackinnon-Hunter (IFC). O grupo A apresentou IFC inicial de -28,43, com recuperação funcional no 5º dia. A drenagem imediata desse hematoma através de uma epineurotomia longitudinal (B) determinou retorno da função ciática normal desde o 1º dia (IFC= -14,42). Tratando o hematoma através da neurólise interfascicular observamos um IFC inicial de -23,69 e retorno da função ciática normal no 3º dia. Os parâmetros histomorfométricos apontaram melhora dos parâmetros de isquemia após os 2 tipos de intervenção cirúrgica aplicadas neste estudo. Não houve diferença entre os tipos de intervenções aplicadas.

Emergence of intraneural hematoma with involvement of peripheral nerves can occur after trauma or coagulation disorders. The decision for expectant management or decompressive surgical techniques is still controversial. Forty male Wistar rats were divided into 4 groups. In group A, an intraneural injection of autologous blood was provided at the right sciatic nerve. In group B, after the hematoma creation, a longitudinal epineurotomy was performed. In the group C (sham-operated), the sciatic nerve was exposed without hematoma. In group D. immediately after the hematoma creation, an interfascicular neurolysis was performed. Nerve function recovery was assessed using the Bain-Mackinnon-Hunter Sciatic Function Index (SFI). At the end of the study, the animals were sacrificed and a specimen of the sciatic nerve at compression midpoint was removed for morphometric analysis. Group A displayed an initial SFI of -28.43, with full functional recovery on the fifth day. Immediate drainage of the hematoma by longitudinal epineurotomy (group B) promoted recovery of normal sciatic function on the first day (SFI -14.42). Addressing the hematoma via interfascicular neurolysis resulted in an initial SFI of -23.69 and recovery of normal sciatic function on the third day. The morphometric variables indicated an improvement of ischemic parameters following both types of surgical intervention.