RAMES MATTAR JUNIOR
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Ortopediae Traumatologia, Faculdade de Medicina - Docente
LIM/41 - Laboratório de Investigação Médica do Sistema Músculoesquelético, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/41 - Laboratório de Investigação Médica do Sistema Músculoesquelético, Hospital das Clínicas, Faculdade de Medicina - Líder
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article 3 Citação(ões) na Scopus Effect of neurotrophic factor, MDP, on rats' nerve regeneration(2011) FORNAZARI, A. A.; REZENDE, M. R. de; MATTAR JR., R.; TAIRA, R. I.; SANTOS, G. B. dos; PAULOS, R. G.Our objective was to determine the immune-modulating effects of the neurotrophic factor N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) on median nerve regeneration in rats. We used male Wistar rats (120-140 days of age, weighing 250-332 g) and compared the results of three different techniques of nerve repair: 1) epineural neurorrhaphy using sutures alone (group S - 10 rats), 2) epineural neurorrhaphy using sutures plus fibrin tissue adhesive (FTA; group SF - 20 rats), and 3) sutures plus FTA, with MDP added to the FTA (group SFM - 20 rats). Functional assessments using the grasp test were performed weekly for 12 weeks to identify recovery of flexor muscle function in the fingers secondary to median nerve regeneration. Histological analysis was also utilized. The total number and diameter of myelinated fibers were determined in each proximal and distal nerve segment. Two indices, reported as percentage, were calculated from these parameters, namely, the regeneration index and the diameter change index. By the 8th week, superiority of group SFM over group S became apparent in the grasping test (P = 0.005). By the 12th week, rats that had received MDP were superior in the grasping test compared to both group S (P < 0.001) and group SF (P = 0.001). Moreover, group SF was better in the grasping test than group S (P = 0.014). However, no significant differences between groups were identified by histological analysis. In the present study, rats that had received MDP obtained better function, in the absence of any significant histological differences.- INTERCOSTAL NERVE TRANSFER TO THE BICEPS MOTOR BRANCH IN COMPLETE TRAUMATIC BRACHIAL PLEXUS INJURIES(2015) BAIK, Alvaro; IAMAGUCHI, Raquel Bernardelli; SILVA, Gustavo Bersani; PAULOS, Renata Gregorio; KIYOHARA, Leandro Yoshinobu; SORRENTI, Luiz; MENEZES, Klicia de Oliveira Costa Riker Teles de; REZENDE, Marcelo Rosa de; WEI, Teng Hsiang; MATTAR JUNIOR, RamesThe purpose of this report is to critically evaluate our results of two intercostal nerve transfers directly to the biceps motor branch in complete traumatic brachial plexus injuries. From January 2007 to November 2012, 19 patients were submitted to this type of surgery, but only 15 of them had a follow-up for >= 2 years and were included in this report. The mean interval from trauma to surgery was 6.88 months (ranging from 3 to 9 months). Two intercostals nerves were dissected and transferred directly to the biceps motor branch. The mean follow-up was 38.06 months (ranging from 24 to 62 months). Ten patients (66.6%) recovered an elbow flexion strength >= M3. Four of them (26.66%) recovered a stronger elbow flexion >= M4. One patient (6.25%) recovered an M2 elbow flexion and four patients (26.66%) did not regain any movement. We concluded that two intercostal nerve transfers to the biceps motor branch is a procedure with moderate results regarding elbow flexion recovery, but it is still one of the few options available in complete brachial plexus injuries, especially in five roots avulsion scenario. (C) 2015 Wiley Periodicals, Inc.
- A REINFORCEMENT OF THE SUTURED MICROVASCULAR ANASTOMOSIS WITH FIBRIN GLUE APPLICATION: A RETROSPECTIVE COMPARATIVE STUDY WITH THE STANDARD CONVENTIONAL TECHNIQUE(2017) CHO, Alvaro Baik; PAULOS, Renata Gregorio; BERSANI, Gustavo; IAMAGUCHI, Raquel Bernardelli; TORRES, Luciano Ruiz; WEI, Teng Hsiang; RESENDE, Marcelo Rosa De; MATTAR JUNIOR, RamesPurpose: Although a reasonable number of studies report satisfactory results with fibrin glue application in microvascular anastomosis since 1977, its utilization in the clinical setting has being scant in the literature. The aim of this study was to report the cumulated experience with the fibrin glue in free flaps over a period of 10 years, comparing the survival rate with the standard sutured anastomosis. Patients and methods: From August 2001 through November 2014, 83 consecutive free flaps were performed by a team of surgeons from two hospitals. About 56 flaps were performed in 56 patients using the fibrin glue augmented microvascular anastomosis and 27 flaps were performed in 27 patients using the conventional anastomosis technique. The decision on whether or not the fibrin glue should be used at the anastomoses was based on its availability and whose surgeon was performing the anastomoses. About approximately 60% of sutures stitches were used that would be used in a conventional anastomosis, when fibrin glue application was anticipated (ranging from 5 to 7 sutures in the arteries and 5 to 8 in the veins). Results: The overall survival rate of the flaps performed with fibrin glue application was 92.85%. In one case, a revision of the venous anastomosis was required due to early flap congestion. Four cases (7.14%) had failure of the first free flap and two of them were submitted to another free flap without fibrin glue application. In the flaps performed with the conventional anastomosis technique the survival rate was 92.59%. This difference was not statistically significant (P=0.97). Conclusion: The application of fibrin glue in microvascular anastomoses did not increase the rate of flap loss and had a potential to reduce the number of sutures required to complete an anastomosis by its sealing effect. (C) 2016 Wiley Periodicals, Inc.
bookPart Lesões dos nervos periféricos e transferênciais tendíneas(2021) PAULOS, Renata Gregório; MATTAR JUNIOR, Rames- Free gracilis muscle transfer with ulnar nerve neurotization for elbow flexion restoration(2021) REZENDE, Marcelo R. De; VERONESI, Bruno A.; PAULOS, Renata G.; CHO, Alvaro B.; RIBAK, Samuel; JUNIOR, Rames M.Purpose In upper and chronic brachial plexus injuries for which neurological surgery is not a good treatment option, one possibility for gaining elbow flexion is free functional muscle transfer. The primary aim of our study was to evaluate the elbow flexion gain achieved by free gracilis muscle transfer with partial ulnar nerve neurotization. Methods This surgery was performed in 21 patients with upper and chronic (> 12 months) brachial plexus injuries. The level of injury, patient age, the time between trauma and surgery, the affected side, and the aetiology of the lesion were recorded. The primary outcome evaluated was elbow flexion muscle strength, which was measured using the British Medical Research Council (BMRC) scale, in patients with a minimum follow-up period of 12 months. The criterion used to classify elbow flexion as good was a grade of M4 or higher. Results An M4 elbow flexion strength gain was observed in 61.9% of the patients. A gain of M2 or higher was observed in 95.2% of the patients. The mean range of active motion was 77 degrees (range 10 minimum-110 maximum). Conclusion In patients with upper and chronic brachial plexus injuries, free gracilis muscle transfer with ulnar nerve neurotization yields a satisfactory gain in elbow flexion strength and is therefore a good treatment option.
- EFFECT OF HYPERBARIC OXYGEN THERAPY ON NERVE REGENERATION IN RATS(2022) BARROS, Thiago Felipe Dos Santos; PAULOS, Renata Gregorio; IWASE, Fernanda Do Carmo; SANTOS, Gustavo Bispo Dos; REZENDE, Marcelo Rosa De; MATTAR JUNIOR, RamesObjective: To evaluate histological changes in peripheral nerves of rats after sciatic nerve neurorrhaphy, according to the time of exposure to hyperbaric oxygen chamber treatment. Methods: Twenty-five Wistar rats were divided into 5 groups according to the amount of exposure to hyperbaric oxygen chamber treatment. Group 1 was the control and there was no use of hyperbaric oxygen chamber; group 2 received one week of therapy; group 3, two weeks; group 4, three weeks; and group 5, four weeks. After the fourth postoperative week, the animals were submitted to euthanasia and a sciatic nerve sample sent for histological analysis. Axons proximal and distal to the neurorrhaphy were counted with axonal regeneration index measurement. Results: We observed that the number of axons distal to neurorrhaphy increases with the amount of hyperbaric oxygen chamber exposure, the results were more expressive from the third week of treatment. However, the statistical analysis found no significant difference between the groups. Conclusion: The descriptive analysis suggests benefit of using hyperbaric oxygen chamber directly proportional to the time of therapy. The study, however, did not present statistically relevant results, probably due to the reduced sample size. Subsequent studies with more significant sampling would be of great value. Level of Evidence II, Prospective Comparative Study.
- LIMB REPLANTATION AFTER AVULSION INJURIES: TECHNIQUES AND TACTICS FOR SUCCESS(2012) PAULOS, Renata Gregorio; SIMAO, Danielle Tiemi; MATTAR JUNIOR, Rames; REZENDE, Marcelo Rosa de; WEI, Teng Hsiang; TORRES, Luciano RuizObjectives: Retrospective evaluation of cases of limb replantation after avulsion injuries. Evaluation of the techniques and tactics used, that contributed to success and good functional results. Methods: Forty-three patients' records were assessed. All the cases had been submitted to limb replantation after avulsion injuries. Results: The majority of the cases were young men. The most common injury was to the thumbs. The surgical techniques and tactics used were: nerve grafting, vein grafting, transposition of the digital vessels, limb shortening, and heterotopic replantation. The most commonly used technique was vein graft. The limb survival rate was high (93%), as was patient satisfaction. Conclusion: Replantation after avulsion injury depends on the correct diagnosis of the limb viability and the use of appropriate surgical techniques and tactics for each case. The experience of the team of surgeons and a good hospital structure are essential for good results. There are few articles in medical literature about the indications, techniques and results of limb replantation after avulsion injuries. We believe that this retrospective evaluation can bring new information and contributions to the correct management of this highly complex situation. Level of evidence IV, Case Series.
- RADIOCARPAL FRACTURE DISLOCATIONS: A NEW CLASSIFICATION AND TREATMENT PROPOSAL(2022) PAULA, Emygdio Jose Leomil De; BISNETO, Edgard De Novaes Franca; PAULOS, Renata Gregorio; MATTAR JUNIOR, RamesIntroduction: The radiographic and surgical findings, and treatment of radiocarpal fracture dislocations, were analyzed retrospectively in 40 patients. Materials and Methods: All patients were classified according to Dumontier's radiological classification and compared with the surgical findings. Based on this analysis, a new classification and treatment are proposed. Results: From 1995 to 2018, 40 patients with radiocarpal fracture dislocation underwent surgery. Thirty-six were males and four were females. The mean age was twenty-four years (range: 18-45). Three dislocations were volar dislocations and 37 were displaced dorsally. Initially, 8 (20%) patients were classified as group I, 29 (72.5%) as group II, and 3 (7.5%) remained unclassified. The main variations occurred in group II. Seven fractures were stable after radial styloid fixation and 6 remained unstable. Sixteen fractures presented articular fragments or an interposed capsule, which prevented anatomical reduction using conservative maneuvers. Conclusion: Based in our intraoperative observations and surgical results, we believe that a more detailed classification should be adopted.
- Experimental study of histological changes in vascular loops according to the duration of the postoperative period: Application in reconstructive microsurgery(2017) PAULOS, Renata Gregorio; RUDELLI, Bruno Alves; FILIPPE, Renee Zon; SANTOS, Gustavo Bispo dos; HERRERA, Ana Abarca; RIBEIRO, Andre Araujo; REZENDE, Marcelo Rosa de; HSIANG-WEI, Teng; MATTAR- JR., RamesOBJECTIVES: To analyze the histological changes observed in venous grafts subjected to arterial blood flow as a function of the duration of the postoperative period to optimize their use in free flap reconstructions. METHOD: Twenty-five rats (7 females and 18 males) underwent surgery. Surgeries were performed on one animal per week. Five weeks after the first surgery, the same five animals were subjected to an additional surgery to assess the presence or absence of blood flow through the vascular loop, and samples were collected for histological analysis. This cycle was performed five times. RESULTS: Of the rats euthanized four to five weeks after the first surgery, no blood flow was observed through the graft in 80% of the cases. In the group euthanized three weeks after the first surgery, no blood flow was observed in 20% of the cases. In the groups euthanized one to two weeks after the first surgery, blood flow through the vascular loop was observed in all animals. Moreover, intimal proliferation tended to increase with the duration of the postoperative period. Two weeks after surgery, intimal proliferation increased slightly, whereas strong intimal proliferation was observed in all rats evaluated five weeks after surgery. CONCLUSION: Intimal proliferation was the most significant change noted in venous grafts as a function of the duration of the postoperative period and was directly correlated with graft occlusion. In cases in which vascular loops are required during free flap reconstruction, both procedures should preferably be performed during the same surgery.
- MEDIAN NERVE FASCICLE TRANSFER VERSUS ULNAR NERVE FASCICLE TRANSFER TO THE BICEPS MOTOR BRANCH IN C5-C6 AND C5-C7 BRACHIAL PLEXUS INJURIES: NONRANDOMIZED PROSPECTIVE STUDY OF 23 CONSECUTIVE PATIENTS(2014) CHO, Alvaro Baik; PAULOS, Renata Gregorio; RESENDE, Marcelo Rosa de; KIYOHARA, Leandro Yoshinobu; SORRENTI, Luiz; WEI, Teng Hsiang; BOLLIGER NETO, Raul; MATTAR JUNIOR, RamesThe purpose of this study was to observe whether the results of the median nerve fascicle transfer to the biceps are equivalent to the classical ulnar nerve fascicle transfer, in terms of elbow flexion strength and donor nerve morbidity. Twenty-five consecutive patients were operated between March 2007 and July 2013. The patients were divided into two groups. In Group 1 (n=8), the patients received an ulnar nerve fascicle transfer to the biceps motor branch. In Group 2 (n=15), the patients received a median nerve fascicle transfer to the biceps motor branch. Two patients with follow-up less than six months were excluded. Both groups were similar regarding age (P=0.070), interval of injury (P=0.185), and follow-up period (P=0.477). Elbow flexion against gravity was achieved in 7 of 8 (87.5%) patients in Group 1, versus 14 of 15 (93.3%) patients in Group 2 (P=1.000). The level of injury (C5-C6 or C5-C7) did not affect anti-gravity elbow flexion recovery in both the groups (P=1.000). It was concluded that the median nerve fascicle transfer to the biceps is as good as the ulnar nerve fascicle transfer, even in C5-C7 injuries. (C) 2014 Wiley Periodicals, Inc.