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
16 resultados
Resultados de Busca
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- Do two venous anastomoses decrease venous thrombosis during limb reconstruction?(2019) IAMAGUCHI, Raquel; BURGOS, Felipe; SILVA, Gustavo; CHO, Alvaro; NAKAMOTO, Hugo; TAKEMURA, Renan; WEI, Teng; REZENDE, Marcelo de; JR, Rames MattarBACKGROUND: The optimal number of veins to be anastomosed in perforator flaps for limb reconstruction and its influence on the results remain controversial. Venous thrombosis of microvascular anastomoses is a commonly recorded complication in soft tissue reconstruction. OBJECTIVE: To evaluate the effect of two venous anastomoses in the incidence of venous thrombosis for limb reconstruction using anterolateral thigh (ALT) microsurgical free flaps. METHODS: This was a cross-sectional study on patients undergoing limb reconstruction using ALT flap during 2014-2017. Perioperative information was recorded and patients were divided in two groups: group 1 (one venous anastomosis; 17 patients) and group 2 (two venous anastomoses; 21 patients). Complications were investigated. RESULTS: Overall, 38 microsurgical flaps were included. The mean age was 33 years, and 32 patients were male. The most prevalent wounds were traumatic. Group 1 presented a higher complication rate than group 2 (47% vs. 24%; p = 0.065), although the difference was not significant. Group 1 presented a higher rate of venous anastomotic thrombosis (p = 0.032) than group 2. The overall success rate was 92%. CONCLUSION: For limb reconstruction using ALT microsurgical free flaps, two venous anastomoses are associated with a low rate of venous thrombosis in microvascular anastomoses.
- Biomechanical comparison of the four-strand cruciate and Strickland techniques in animal tendons(2013) IAMAGUCHI, Raquel Bernardelli; VILLANI, William; REZENDE, Marcelo Rosa; WEI, Teng Hsiang; CHO, Alvaro B.; SANTOS, Gustavo Bispo dos; MATTAR JR., RamesOBJECTIVE: The objective of this study was to compare two four-strand techniques: the traditional Strickland and cruciate techniques. METHODS: Thirty-eight Achilles tendons were removed from 19 rabbits and were assigned to two groups based on suture technique (Group 1, Strickland suture; Group 2, cruciate repair). The sutured tendons were subjected to constant progressive distraction using a universal testing machine (Kratos (R)). Based on data from the instrument, which were synchronized with the visualized gap at the suture site and at the time of suture rupture, the following data were obtained: maximum load to rupture, maximum deformation or gap, time elapsed until failure, and stiffness. RESULTS: In the statistical analysis, the data were parametric and unpaired, and by Kolmogorov-Smirnov test, the sample distribution was normal. By Student's t-test, there was no significant difference in any of the data: the cruciate repair sutures had slightly better mean stiffness, and the Strickland sutures had longer time-elapsed suture ruptures and higher average maximum deformation. CONCLUSIONS: The cruciate and Strickland techniques for flexor tendon sutures have similar mechanical characteristics in vitro.
- Do technical components of microanastomoses influence the functional outcome of free gracilis muscle transfer for elbow flexion in traumatic brachial plexus injury?(2021) MARTINS-FILHO, Francisco Vilmar Felix; IWASE, Fernanda do Carmo; SILVA, Gustavo Bersani; CHO, Alvaro Baik; WEI, Teng Hsiang; REZENDE, Marcelo Rosa de; JR, Rames Mattar; IAMAGUCHI, Raquel BernardelliIntroduction: The traumatic lesions of the brachial plexus in adults are devastating injuries causing continuous severe functional impairment for both work and daily living activities. The restoration of elbow flexion is one of the most important movements for patient recovery to previous activities. Free gracilis muscle transfer has good outcomes for cases with late presentation or as a rescue surgery to regain elbow flexion, however, bad results are present in all cohorts with insufficient recovery of muscle strength for elbow flexion. A number of hypotheses can be postulate to explain the fair results observed in some cases of free gracilis muscle transfer for elbow flexion. Most studies in the current literature compare the choice of the donor nerve used in neurotization and nerve grafts. The aim of this study is to evaluate if technical components of microvascular anastomosis could influence the functional outcome of free functional muscle transfer for elbow flexion in adult patients with traumatic brachial plexus injury. Material and methods: Included all adult patients with traumatic brachial plexus injury submitted to free functional gracilis muscle transfer for elbow flexion. The complications and functional results according to British Medical Research Council (BMRC) score were recorded. Results: We assessed 26 patients with mean age of 32.8 years. The most common donor nerve for gracilis muscle was the accessory nerve in 18 patients. Eighteen patients presented with good result (M3/M4). The mean ischemia time was higher for patients with bad results (132 minutes) comparing with patients with good results (122 minutes). Patients with only one venous anastomosis had 41% of poor functional outcome compared with 22% of cases with two venous anastomoses. No statistically significant difference in the ischemia time of the cases with good or poor functional outcome was observed (p = 0.657), as for the number of venous anastomoses (p = 0.418). Conclusion: Our study observes that patients with only one venous anastomoses for drainage of free gracilis and those with longer intraoperative ischemia time had higher incidence of poor functional outcome of free gracilis muscle transfer for elbow flexion, but not statistically significant. Level of proof: II; prospective cross-sectional study.
- Detecção de trombose venosa em retalhos livres por medidas de glicemia capilar(2012) MILLAN, Lincoln Saito; ISHIDA, Luiz Carlos; CHOI, Esther Mihwa Oh; GIACCHETTO JUNIOR, Enio Cesar; WEI, Teng Hsiang; MATTAR JÚNIOR, Rames; FERREIRA, Marcus CastroBACKGROUND: Monitoring of free flaps after surgery is vitally important, especially in the first few hours because the timing of reoperation can determine flap salvage or loss. To date, no study has examined the decision to reoperate on a flap based on the objective measure of glycemia or a comparison between flaps that showed good outcomes and those that showed vascular damage. The objective of this study was to evaluate the validity of blood glucose measurements within the flap as a method for monitoring free flaps and to compare the efficacy of this method with that of clinical assessments. METHODS: The study was prospective, included 16 patients with free flaps, and was conducted from May 2012 to July 2012. A team of professionals not involved in the surgery evaluated capillary glycemia. Flaps were clinically evaluated during the immediate postoperative period, on ICU admission, at every 3 hours, and as needed. RESULTS: Of the 16 patients, 5 (31.3%) had venous thrombosis in the first 24 hours. Statistically significant differences were noted in capillary glycemia in patients with or without venous thrombosis in measurements obtained 6, 9, and 12 hours after surgery (P < 0.05). CONCLUSIONS: The measurement of capillary glycemia was not superior to clinical evaluation by an experienced professional for the detection of venous thrombosis within free flaps.
- Microsurgical Reconstruction in an Orthopedic Hospital: Indications and Outcomes in Adults(2022) IAMAGUCHI, Raquel Bernardelli; MACEDO, Lucas Sousa; CHO, Alvaro Baik; REZENDE, Marcelo Rosa de; MATTAR JÚNIOR, Rames; WEI, Teng HsiangAbstract Objective Advances in reconstructive microsurgery in orthopedic surgery provided better functional and aesthetic results and avoided many indications for amputation. In high-volume trauma and orthopedic hospitals, microsurgical reconstruction is essential to reduce costs and complications for these complex orthopedic defects. We describe a microsurgical approach to traumatic wounds, tumor resection, bone defects, and free muscle transfer, performed by an orthopedic microsurgery unit. The objective of the present study was to evaluate predictor factors for outcomes of microsurgical flaps for limb reconstruction, and to provide a descriptive analysis of microsurgical flaps for orthopedic indications. Methods Cross-sectional prospective study that included all consecutive cases of microsurgical flaps for orthopedic indications from 2014 to 2020. Data were collected from personal medical history, intraoperative microsurgical procedure, and laboratory blood tests. Complications and free-flap outcomes were studied in a descriptive and statistical analysis. Results We evaluated 171 flaps in 168 patients; the indications were traumatic in 66% of the patients. Type III complications of the Clavien-Dindo Classification were observed in 51 flaps. The overall success rate of the microsurgical flaps was 88.3%. In the multivariate analysis, the risk factors for complications were ischemia time ≥ 2 hours (p= 0.032) and obesity (p= 0.007). Partial flap loss was more common in patients with thrombocytosis in the preoperative platelet count (p= 0.001). Conclusion The independent risk factors for complications of microsurgical flaps for limb reconstruction are obesity and flap ischemia time ≥ 2 hours, and presence of thrombocytosis is a risk factor for partial flap loss.
- 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.
- Structured evaluation of a comprehensive microsur- gical training program(2021) MATTAR, Tiago Guedes da Motta; SANTOS, Gustavo Bispo dos; TELLES, Joao Paulo Mota; REZENDE, Marcelo Rosa de; WEI, Teng Hsiang; MATTAR JUNIOR, RamesOBJECTIVES: This study proposed a structured microsurgical training program and evaluated it with the assistance of a large sample of surgeons. METHODS: The practical course comprised 16 sessions of approximately 4 hours each. This included two sessions for suturing rubber gloves and two sessions for suturing arteries, veins, and nerves in chicken thighs. The other sessions were performed on the femoral vessels of rats: 5 sessions for end-to-end arterial anastomosis, 5 for endto-end venous anastomosis, 1 for arterial grafting, and 1 for end-to-side anastomosis. We conducted a structured assessment of the microsurgical skills in each training session. RESULTS: In this study, 89 surgeons were evaluated. The mean scores for the different procedures were as follows: glove suturing, 33.3 +/- 0.59; chicken nerve end-to-end anastomosis, 40.3 +/- 0.49; chicken artery suturing, 40.9 +/- 0.36; chicken vein suturing, 42.3 +/- 0.36; graft interposition, 44.8 +/- 0.7; and end-to-side anastomosis, 43.7 +/- 0.63 (p<0.05 for all). The chicken thigh suturing scores were significantly higher than the rubber gloves suturing scores (p<0.01). There were no differences between scores of the rat artery and chicken thigh suturing procedures (p=0.24). The rat venous anastomosis scores were higher than the rat arterial anastomosis scores (p=0.02), as were graft interposition scores when compared with end-to-end venous anastomosis scores. The end-to-side anastomosis scores did not differ significantly from the grafting scores (p=0.85). The most common errors were inadequate knotting technique and suture rupture due to inadequate technique (both n=88 [98.9%]). CONCLUSION: We propose a 16-step, progressive microsurgical training program to learn the basic microsurgical techniques comprehensively and reliably. The program was evaluated in a large sample of trainees, and it demonstrated the adequacy of the training sequence and results.
- Peri-operative risk factors for complications of free flaps in traumatic wounds - a cross-sectional study(2018) IAMAGUCHI, Raquel Bernardelli; TAKEMURA, Renan Lyuji; SILVA, Gustavo Bersani; ALVES, Jairo Andre de Oliveira; TORRES, Luciano Ruiz; CHO, Alvaro Baik; WEI, Teng Hsiang; REZENDE, Marcelo Rosa de; MATTAR JR., RamesIntroduction Indication of free tissue transfer for limb reconstruction continues to grow, and despite the good results with this treatment option, complications can impair the functional results and cause a raise in health costs, with prolonged hospitalization. Therefore, peri-operative surgical information and comorbidities were described and analyzed, for identification of independent risk factors for complications of free flaps results for traumatic wounds. For our knowledge, intraoperative ischemia time of free flap was not previously studied for post-traumatic limb reconstruction, which could influence results, in these traumatic cases, with the highest rates of complications among microsurgical flap reconstructions. Methods From July 2014 to January 2017, all patients with free flaps for limb reconstruction were consecutively included. Data on personal medical history, intra-operative microsurgical procedure, and laboratory tests were collected and complications analyzed. Descriptive and inferential statistics were performed. Results Sixty-two free flaps for traumatic limb reconstruction in 60 patients were studied. We observed a higher rate of complications in patients who underwent surgery > seven days after the trauma, patients with obesity, when used recipient veins from the superficial system for drainage of the flap, and in those in whom the ischemia time of the free flap was higher in univariate analyzes. After logistic regression, the remaining independent risk factors for complications were ischemia time of free flap > two hours and obesity. The presence of thrombocytosis was associated with partial flap loss. Conclusions The independent risk factors for complications were ischemia time of free flap > two hours and obesity.
- IS OBESITY A RISK FACTOR FOR FREE VASCULARIZED FIBULAR FLAP COMPLICATIONS?(2019) IAMAGUCHI, Raquel Bernardelli; MORAES, Marco Aurelio de; SILVA, Gustavo Bersani; CHO, Alvaro Baik; IWASE, Fernanda do Carmo; WEI, Teng Hsiang; REZENDE, Marcelo Rosa de; MATTAR JR., RamesObjective: Although our knowledge of bone reconstruction through microsurgery has increased, the vascularized fibula flap remains one of the most difficult free flap reconstructions to perform, and complications remain a challenge. The incidence of obesity is increasing and is associated with higher rates of free flap complications, which can lead to disastrous results. Since there is no consensus in literature regarding the influence of obesity on free flap outcomes in orthopedic surgeries that require segmental bone reconstruction, the objective of this study was to determine whether obesity increases the risk of post-operative complications (Clavien-Dindo grade III) after free vascularized fibular flap surgery. Methods: A cohort study was conducted in all patients undergoing free flap limb reconstructions between July 2014 and July 2018. Patients were separated in two groups based on their body mass index (BM I): non-obese and obese (BMI >= 30 kg/m(2)). Results: Twenty-three free vascularized fibular flaps were studied. The indications included trauma in 13, tumors in 7, and congenital pseudarthrosis of the tibia in 3. Obese patients were associated with an increase in surgical complications (p=0.038). During the final follow-up, consolidation was obtained in 17 patients (74%). Conclusion: Obesity is a risk factor for complications in free vascularized fibular flap surgery.