ABSTRACT
PURPOSE: To present an animal model to assess the effects of end-to-side innervation in the heterotopically transplanted model with reduced chances of neural contamination. METHODS: The medial portion of the gastrocnemius muscle in wistar male rats was isolated and its pedicle dissected and performed a flap in the abdominal portion. To prevent neural contamination in the abdominal region, the muscle was wrapped with a Goretex(r) sheet. The specimens were divided into 2 groups (G). In G1 was performed an end-to-end suture between tibial nerve of the gastrocnemius and femoral motor nerve and between the saphenous sensory nerve and the motor nerve. In G2 was performed a end-to-side suture between the tibial nerve and the motor femoral and between the tibial nerve and saphenous motor nerve. The specimens were evaluated 60 days later to check the structure of the neurorraphy. Sections were obtained proximal and distal to the coaptation site. RESULTS: The medial gastrocnemius muscle had the advantage of maintaining visible mass after 60 days. No disruption of the coaptation site was found. No major injury to the donor nerve was seen in group 2. CONCLUSION: The proposed model is simple, reproduciple and prevent the neural contamination in the flap in end-to-side suture. .
Subject(s)
Animals , Male , Models, Animal , Muscle, Skeletal/innervation , Muscle, Skeletal/transplantation , Nerve Transfer/methods , Suture Techniques , Transplantation, Heterotopic/methods , Femoral Nerve/transplantation , Microscopy, Electron , Microsurgery/methods , Rats, Wistar , Reproducibility of Results , Plastic Surgery Procedures/methods , Surgical Flaps , Time Factors , Tibial Nerve/transplantationABSTRACT
PURPOSE: To compare muscle reinnervation in one and two surgical stages using end-to-side neurorrhaphy (ESN) without donor nerve injury. METHODS: The experiment was performed on four groups of 20 rats. Group 1 (G1), one stage, received the graft which was sutured to the tibial nerve, with ESN, and its free stump was sutured end-to-end to the distal stump of the sectioned peroneal nerve (PN), all in the same operation. In Group 2 (G2), two stages, the nerve graft was sutured to the tibial nerve, with ESN. Two months later the PN was sectioned and its distal stump connected to the distal stump of the graft as in G1. Normal control group (Gn) received the graft only sutured to the tibial nerve, with ESN. Denervated control group (Gd), as well received the graft and had the PN sectioned and its two stumps buried in adjacent musculature, with the aim of denervating the cranial tibial muscle (CTM), the target of this study. The parameters used to evaluate CTM reinnervation were muscle mass, muscle fiber's minimum diameter and area. RESULTS: The mean CTM mass, the average of the muscular fibers areas and the average of the muscular fiber minimum diameters was higher (all p<0.0001) in G2 than in G1. Comparing the four groups, these parameters had their maximum expression in Gn and the minimum in Gd, as expected. CONCLUSION: The two stages showed better muscle reinnervation than one stage.
OBJETIVO: Comparar a reinervação muscular com enxerto de nervo em um e dois tempos operatórios, utilizando a neurorrafia término-lateral (NTL) sem lesão do nervo doador. MÉTODOS: Vinte ratos foram distribuídos em quatro grupos. O grupo 1 (G1), um estágio, recebeu o enxerto que foi suturado ao nervo tibial (NT), por meio de NTL, e seu coto livre foi suturado por NTL ao coto distal do nervo peroneal (NP), seccionado a um centímetro do NT, na mesma cirurgia. O grupo 2 (G2), dois estágios, recebeu o enxerto de nervo na primeira cirurgia, como já descrito. Dois meses depois, na segunda cirurgia, o NP foi seccionado e seu coto distal ligado ao coto distal do enxerto como em G1. O grupo controle de normalidade (Gn) recebeu o enxerto da mesma forma, apenas. E o grupo controle de denervação (Gd), além de receber o enxerto, teve o NP seccionado e seus cotos sepultados na musculatura adjacente, com a finalidade de denervar o músculo tibial cranial (MTC), alvo deste estudo. Os parâmetros utilizados para avaliar a reinervação do MTC foram massa muscular, diâmetro mínimo da fibra muscular e área. RESULTADOS: O grupo G2 apresentou superioridade (p<0,0001) em relação ao G1 na massa do MTC, no diâmetro mínimo e na área das fibras musculares. Na comparação entre os quatro grupos, estes mesmos parâmetros tiveram sua expressão máxima em Gn e mínima em Gd, como era esperado. CONCLUSÃO: A reinervação muscular em dois estágios apresenta melhor resultado quando comparada à técnica em um tempo.
Subject(s)
Animals , Male , Rats , Facial Nerve/transplantation , Muscle, Skeletal/innervation , Nerve Regeneration/physiology , Nerve Transfer/methods , Tibial Nerve/transplantation , Facial Nerve/physiology , Models, Animal , Muscle, Skeletal/transplantation , Rats, Wistar , Tibial Nerve/physiologyABSTRACT
PURPOSE: Compare two new methods with the traditional end-to-side neurorrhaphy. METHODS: Rats were divided into four groups. In A-L group the peroneal nerve was sectioned and the distal stump was connected to the lateral of the tibial nerve (donor) with two 10-0 nylon points. In A-R group two perineurium flaps embraced the donor nerve. In the B-R group a suture embraced the donor nerve. Group B-L was the control. After six months tibial cranial muscle mass and morphometry of the distal stump of the peroneal nerve were evaluated. RESULTS: Muscle mass in groups A-R, A-L and B-R were lower than B-L group (p<0.0001) an equal between themselves (p>0.05). Groups A-R, B-R and A-L had a lower number of nerve fibers when compared with B-L (p=0.0155, p=0.016, p=0.0021). CONCLUSION: The three types of neurorrhaphy showed no differences related to muscle mass and number of nerve fibers suggesting that the embracing with a single suture has great potential due its simplicity and usefulness in deep areas.
OBJETIVO: Comparar dois novos métodos com o método tradicional da neurorrafia término-lateral. MÉTODOS: Os ratos foram separados em quatro grupos. No grupo A-E o nervo peroneal foi seccionado e o coto distal foi suturado à lateral do nervo tibial com dois pontos de nylon 10-0. No grupo A-D duas abas de epi-perineuro abraçaram o nervo doador. No grupo B-D foi realizada sutura com um único ponto abraçando o nervo doador. O grupo B-E foi o controle. Após seis meses foram observados massa do músculo tibial cranial e morfometria do coto distal do nervo peroneal. RESULTADOS: Foi encontrada menor massa muscular nos grupos A-D, A-E e B-D quando comparados com o grupo B-E (p<0.0001) e mesma massa quando comparados entre si (p>0,05). Os grupos A-D, A-E e B-D apresentaram menor número de fibras nervosas quando comparados ao grupo B-E (p=0,0155; p=0,016; p=0,0021) e mesmo número quando comparados entre si. CONCLUSÃO: Os três tipos de neurorrafia não apresentaram diferenças relacionadas à massa muscular e número de fibras nervosas sugerindo que a sutura abraçante com apenas um ponto apresente grande potencial em áreas cirúrgicas mais profundas.
Subject(s)
Animals , Rats , Muscle, Skeletal/innervation , Nerve Transfer , Peroneal Nerve/surgery , Suture Techniques/adverse effects , Tibial Nerve/surgery , Anastomosis, Surgical , Models, Animal , Muscle, Skeletal/pathology , Peroneal Nerve/transplantation , Random Allocation , Rats, Wistar , Tibial Nerve/transplantationABSTRACT
Objective: We compared end-to-side neurorraphy with and without the perineural sheath. Method: Twenty rats were used. The peroneal nerve was sectioned and the distal end was sutured to the lateral face of the tibial nerve. We removed the perineural sheath only on the right side, but not on the left side. The proximal end of the peroneal nerve was curved back approximately at a 100 angle and implanted into the adductor muscle. Six months later, the 14 surviving animals were submitted to electrophysiological tests, sacrificed, and the nerves and muscles were taken for histological exams. Results: On the right side, the muscles that had positive response needed and average of 258.89 mV (+ 92.31) of electric stimulus and on the left side 298.34 mV (+139.32). The average weight of the tibial cranial muscles of the right side was 0.47 g (0.18) and for the left side 0.45 g (0.15). The distal end of the peroneal nerve showed averages of 310.29 (+191.34) nerve fibers on the right side and 287.71 (+183.60) on the left side. The tibial nerve above the neurorraphy showed averages of 939.46 (+223.51) nerve fibers on the right side and 959.46 (+327.48) on the left side. The tibial nerve below the neurorraphy showed averages of 935.17 (+298.65) nerve fibers on the right side and 755.31 (+323.26) on the left side. The average areas of the right tibial cranial muscles were 0.0162 m2 (+0.008), after 230 magnification, and 0.0152 m2 (0.0064) for the left tibial cranial muscles. The histological features of the tibial cranial muscles, taking normal as 100 per cent, were 78.21 (+20.75) on the right side and 82.14 (+15.89) on the left side. The statistical analysis (Student's t test) did not reveal any difference (p<0.05) among right and left sides for all variables. Conclusion. The authors concluded that the two neurorraphies (with and without perinerium) did not show any difference regarding morphological and electrophysiological features studies.