Browsing by Author "Melean, Patricio"
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Item Magnetic Resonance Imaging Evaluation of the Integration and Maturation of Semitendinosus-Gracilis Graft in Anterior Cruciate Ligament Reconstruction Using Autologous Platelet Concentrate(Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 26, No 10 (October), 2010: pp 1318-1325, 2010) Figueroa, David; Melean, Patricio; Calvo, Rafael; Vaisman, Alex; Zilleruelo, Nicolás; Figueroa, Francisco; Villalón, gnacioPurpose: To evaluate integration and maturation of semitendinosus-gracilis (STG) grafts in anterior cruciate ligament (ACL) reconstruction with magnetic resonance imaging (MRI) in patients who underwent ACL reconstruction with STG with and without autologous platelet concentrate (APC). Methods: A randomized single–blinded evaluator prospective study was performed in 2 consecutive series of patients who underwent reconstruction over a 14-month period: 30 with APC use (group A) and 20 as control subjects (group B). At 6 months, an MRI evaluation was performed, with observation of the graft’s maturation and presence or absence of synovial fluid at the tunnel-graft interface. To facilitate interpretation, a scoring scale was designed to evaluate graft integration and maturation. Results: Regarding the presence of synovial fluid at the bone-graft interface, the test was negative in 86.84% of patients in group A and 94.74% in group B. A disorganized autograft signal pattern was found in 2.63% in group A and 5.26% in group B. Signal intensity was considered hypointense in 63.16% in group A and 42.11% in group B, isointense in 34.21% in group A and 52.63% in group B, and hyperintense in 0% in both groups. The final mean score was 4.45 points in group A and 4.2 points in group B (P .05). Poor integration was found in 2.63% in group A and 5.26% in group B (P .214). Good integration was found in 97.37% in group A and 94.74% in group B (P .784). Conclusions: In our consecutive series of patients who underwent ACL reconstruction with STG grafts, 1 group with intraoperative APC use versus a control group, followed up by MRI at 6 months after reconstruction, we did not find any statistically significant benefit in the APC group in terms of integration assessment and graft maturation (ligamentization). Level of Evidence: Level III, case-control studyItem Osteochondral autografts in full thickness patella cartilage lesions(2011) Figueroa, David; Melean, Patricio; Calvo R., Rafael; Gili, Federico; Zilleruelo, Nicolás; Vaisman, AlexThe purpose of this study was to evaluate clinical, functional and imaging results of full thickness patella cartilage lesions treated with osteochondral autografts (OCA). We studied a consecutive case series of 10 patients. At follow-up, Lysholm and International Knee Documentation Committee (IKDC) scores were obtained. Magnetic resonance imaging (MRI) evaluation was performed at an average of 8 months post-op. The average cartilage lesion area was 1.2 cm(2). An average of 1.9 grafts was used per patient. The average Lysholm scores were: pre-op 73.8 +/- 8.36; post-op 95 +/- 4.47 points (p < 0.05). The average IKDC post-op score was 95 +/- 1.74 points. No postoperative complications were registered. In the MRI analysis we found that in all cases. OCA presented flush characteristics when compared with adjacent cartilage. The majority of cases presented no fissures in the graft-receptor interface (60%). In 80% we observed mild bone marrow edema around the graft. According to the International Cartilage Research Society (ICRS) cartilage lesions classification, all grafts were considered 1A; in the periphery cartilage was classified as 1A in 60%. We conclude that patellar OCA is a good alternative for the treatment of full thickness patellar cartilage lesions, offering good clinical, functional and imaging results at midterm follow-up. (C) 2010 Elsevier B.V. All rights reserved.Item Steroids and Platelet-Rich Plasma as Coadjuvants to Microfracture for the Treatment of Chondral Lesions in an Animal Model: Can the Healing Be Enhanced?(Sage Publications, 2012) Vaisman, Alex; Figueroa, David; Calvo, Rafael; Espinosa, Maximiliano; Melean, Patricio; Gallegos, Marcela; Conget, PauletteObjective: The aim of this study was to evaluate the contribution to hyaline cartilage regeneration of the microfracture (MFx) technique plus intraarticular betamethasone (BMS) or platelet-rich plasma (PRP). Design: Full-thickness chondral defects of 3 × 6 mm2 were surgically performed in both femoral condyles of each knee in 13 New Zealand rabbits and then treated with MFx associated with intraarticular BMS or PRP. At 12 weeks postimplantation, the animals were killed and the condyles were characterized macroscopically, molecularly according to collagen type II and I gene expression (quantitative reverse transcriptase–polymerase chain reaction), and histologically (hematoxylin–eosin staining). For the latter, samples were scored using the International Cartilage Repair Society visual histological scale. Data of MFx/BMS-treated and MFx/PRP-treated condyles were compared against untreated, MFx-treated, or normal condyles without lesions. Results: Our macroscopic findings showed that in MFx/BMS-treated and MFx/PRP-treated groups, the defects were filled with an irregular, partially rough tissue similar to the MFx-treated group. No differences in the ratio between collagen type II versus collagen type I expression were observed among groups. Histological changes were observed between MFx/BMS-treated and MFx/PRP-treated groups versus untreated defects mainly in surface regularity and cell distribution. However, International Cartilage Repair Society score analysis did not support statistical differences between MFx/BMS-treated and MFx/PRP-treated groups versus MFx-treated group. Conclusions: These results provide evidence that the use of intraarticular BMS or PRP as coadjuvants to the microfracture technique in the treatment of acute chondral lesions is not associated with a significant improvement of hyaline cartilage regeneration.