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A chronic Achilles tendon rupture is a tendon rupture occurring more than 4-6 weeks after a traumatic injury. Haglund's deformity, caused by bony abnormalities in the ankle (mostly due to osteophyte or bone spur), can cause chronic inflammation and degeneration of the Achilles tendon, eventually leading to rupture. This presents a challenge for clinicians who provide tendon repair procedures. We present a 69-year-old woman who had difficulty moving her left leg and had a deformity on the left leg compared to her right leg after falling nine months before but with pain starting three months before the accident. There was a seven-centimeter gap in the calcaneus with a positive Thompson test. The Haglund's deformity on the left calcaneus was visible on the ankle X-ray. The patient had a chronic total rupture of the left Achilles tendon, which was treated with a flexor hallucis longus (FHL) tendon transfer and resection of the deformity. One week after surgery, the patient's ability to walk and the shape of the left leg improved. This case report describes a chronic left Achilles tendon condition that was successfully repaired through tendon repair surgery using FHL tendon transfer and removal of Haglund's deformity.
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Tendão do Calcâneo , Calcâneo , Exostose , Traumatismos dos Tendões , Tendão do Calcâneo/lesões , Tendão do Calcâneo/cirurgia , Idoso , Calcâneo/cirurgia , Exostose/cirurgia , Feminino , Humanos , Ruptura/etiologia , Ruptura/cirurgia , Traumatismos dos Tendões/complicações , Traumatismos dos Tendões/cirurgia , Transferência Tendinosa/métodosRESUMO
BACKGROUND: Achilles tendons heal slower than other tissues, therefore requiring the developmnent of a strategy for accelerating the process. Vascular supply plays an important role in primary tendon healing, especially during the early healing phase. MicroRNA (miR)-210 has been reported as being crucial for angiogenesis, which is a key factor of tissue repair. We report herein that local injection of synthetic miR-210 into the injured Achilles tendon of a rat accelerated healing of the tendon. METHODS: Achilles tendons were transected and repaired via the Kessler suture technique in Sprague-Dawley rats. Then, double stranded (ds) miR-210 was injected into the repaired sites. The control group was injected with non-functioned dsRNA. At 2, 6 and 12 weeks, histological evaluations were performed. At two and six weeks, mechanical testing and angiogenesis were evaluated. Gene expression analysis using real-time polymerase chain reaction (PCR) and immunohistochemistry were performed at two weeks. RESULT: At two and six weeks, regular dense collagen tissue in the miR-210 group was observed and the diameter of collagen fiber in the miR-210 group was significantly higher than in the control. At two weeks, the ultimate failure load was significantly higher than in the control group, and expression of VEGF, FGF2 and type I collagen was upregulated. Abundant vessels in the miR-210 group were observed at two weeks, but there was no significant difference in vessel numbers between the two groups at six weeks. At 12 weeks, repaired Achilles tendons in the miR-210 group consisted of parallel and dense fibers, whereas wavy and loose fibers were still observed in the control group. CONCLUSION: The current study showed that single local injection of synthetic miR-210 promotes Achilles tendon healing in the early phase.
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Tendão do Calcâneo/cirurgia , MicroRNAs/uso terapêutico , Cicatrização/efeitos dos fármacos , Animais , Perfilação da Expressão Gênica , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Resistência à TraçãoRESUMO
PURPOSE: The aims of the present controlled clinical study were to (1) compare patella laxity determined in the outpatient clinic with that in anaesthetized patients and (2) evaluate patella laxity before and after lateral release. METHOD: The study evaluated data on 33 knees from 33 patients (average age 19.7 years) between 2007 and 2011. All patients were diagnosed with recurrent dislocation of the patella. Patellar stability was evaluated in each patient thrice: patellas were first imaged in the outpatient clinic prior to surgery at 45° knee flexion with 20 N stress from the medial to lateral side and from the lateral to medial side; then, at the time of surgery, patella stress images were obtained in the same manner before and after the lateral release procedure. Radiological assessments were performed using the medial stress shift ratio (MSSR) and lateral stress shift ratio (LSSR). RESULTS: There were no significant differences in the LSSR and MSSR before surgery (outpatient data) and in anaesthetized patients before the lateral release procedure. Furthermore, there was no significant difference in MSSR at the time of surgery before and after the lateral release procedure. However, LSSR increased significantly after the lateral release procedure. CONCLUSION: The results of the present study suggest that quantitative patella stress radiography in the outpatient clinic is useful when it comes to investigating laxity of the patella, and that lateral release significantly increases lateral, but not medial, laxity in patients with recurrent patellar dislocation. LEVEL OF EVIDENCE: IV.
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Instabilidade Articular/diagnóstico por imagem , Patela/diagnóstico por imagem , Luxação Patelar/diagnóstico por imagem , Adolescente , Adulto , Criança , Feminino , Humanos , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Patela/cirurgia , Luxação Patelar/cirurgia , Radiografia , Adulto JovemRESUMO
Cells, scaffold, and growth factors are crucially important in regenerative medicine and tissue engineering. Progress in science and technology has enabled development of these three factors, with basic research being applied clinically. In the past decade, we have investigated tissue regeneration in animal models of musculoskeletal disorders by using cells, scaffold, and delivery systems which has been relatively easy to apply and develop in clinical settings. Moreover, microRNA (miRNA), which are important in biological processes and in the pathogenesis of human diseases, have been used in research on regenerative medicine. For the cell source, we focused on mesenchymal stem cells (MSC) and CD34(+) and CD133(+) cells as endothelial progenitor cells for regeneration of musculoskeletal organs. These cells are accessible and safe. For less invasive and more effective therapy, we developed a novel cell-delivery system using magnetic force to accumulate cells at a desired site. Furthermore, administration of synthetic miRNA could enhance tissue regeneration. In our studies, use of these cells combined with a cell-delivery system, miRNA, scaffold, and cytokines has led to effective regeneration of musculoskeletal tissues including cartilage, bone, ligaments, muscle, peripheral nerves, and spinal cord. The current and future objective is more effective and less invasive cell-based therapy with spatial control of transplanted cells by use of an external magnetic force. Analysis of efficiency, safety, and the mechanism of tissue regeneration by cells, scaffold, and miRNA will lead to more promising regenerative medicine, involving the development of a new generation of therapy. This review will focus on our regenerative medicine research, which focuses on clinical application of cells, scaffold, and miRNA.
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Células Progenitoras Endoteliais/transplante , Transplante de Células-Tronco Mesenquimais , MicroRNAs/uso terapêutico , Procedimentos Ortopédicos/métodos , Regeneração , Engenharia Tecidual , Alicerces Teciduais , Animais , Regeneração Óssea , Cartilagem/fisiologia , Humanos , Ligamentos/fisiologia , Músculo Esquelético/fisiologia , Regeneração Nervosa , Medula Espinal/fisiologiaRESUMO
Background: Anterior cruciate ligament (ACL) injury is one of the most prevalent factors contributing to knee instability worldwide. This study aimed to evaluate modified metal fixation techniques for ACL reconstruction compared to factory-made implants, such as polyether ether ketone (PEEK) screws, bioabsorbable screws, and modified metal implants. Methods: A retrospective cohort analysis was conducted to assess the functional outcomes of ACL using various fixation methods. Patients who underwent arthroscopic ACL reconstruction at several healthcare facilities were included in the study. The functional outcomes were evaluated using the Lysholm Knee Scoring Scale and the International Knee Documentation Committee (IKDC) score questionnaire at 6- and 12 months post-surgery. Statistical analyses, including the Shapiro-Wilk test and analysis of variance, were performed to compare outcomes among the fixation groups. Results: Thirty-three patients who underwent ACL reconstruction surgery with varying distributions across the three fixation groups (modified metal implants, PEEK screws, and bioabsorbable screws) were included in the study. As measured by the Lysholm and IKDC scores at 6- and 12 months post-surgery, the PEEK group demonstrated the highest average scores. Nevertheless, these functional outcomes were not significantly different between the groups (p = 0.140, 0.770, 0.150, and 0.200). These findings align with those of meta-analyses comparing different fixation methods for ACL reconstruction. Conclusions: While acknowledging the small sample size as a limitation, this study suggests that modified metal implants represent viable options for ACL reconstruction. The selection of fixation methods should consider patient characteristics and preferences, emphasizing biomechanical stability and long-term outcomes. Further research is needed to validate these findings and explore their biomechanical properties and cost-effectiveness.
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Background: Talus fractures are extremely uncommon, accounting for approximately 1 % of foot and ankle fractures. The talar neck fracture has a high probability of damaging the anastomotic ring, which would interrupt blood circulation to talar body and cause serious issues with fracture healing and integrity. Due to insufficient radiological and clinical examination, approximately 39 % of midfoot and ankle fractures could be undiagnosed after initial evaluation. Talus fractures account for about half of these missed fractures. Anatomic reduction and advanced fixation methods can be performed in the management of neglected talus neck fracture for the purpose of improving functional outcome. Case report: A 30-year-old male patient presented with swelling and pain on the right foot while walking for three months. He had previously fallen about two meters from stairs three months back. Instead of going to the hospital, he received conventional massage therapy. Three months later, he came to us complaining of chronic, dull aching, swelling, and continuous pain when walking and standing. After radiology evaluation, the patient was diagnosed with neglected nonunion type III Hawkins fracture of the neck talus and managed by double incision approach, Iliac crest cancellous bone graft, open reduction and internal fixation (ORIF) with cannulated screw. He was able to return to full weight bearing and his previous activity without experiencing any pain after 14 months. Conclusion: Open reduction and internal fixation (ORIF) with Iliac crest cancellous bone graft is a reliable methods for neglected non-union type III Hawkins fracture of neck talus with great functional outcomes after 14 months of follow up.
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Background: This study aims to prove the healing results (regeneration) in cartilage defects using a combination treatment of microfractures and transplantation synovium-platelet rich fibrin (S-PRF). Methods: A cartilage defect was made in the trochlear groove of the knee of adult New Zealand white rabbits, and was classified into three treatment groups. The group 1 was cartilage defect without treatment, 2 with microfracture treatment, and 3 with microfracture covered with a synovium-platelet rich fibrin (S-PRF) membrane. Twelve weeks after the intervention, the animals were macroscopically and histologically examined, and evaluated by the International Cartilage Repair Society (ICRS). Additionally, the expression of aggrecan and type 2 collagen was examined by real-time-PCR. Results: The ICSR scores for macroscopic were significantly higher in the microfracture and S-PRF transplant group than in the other groups. Also, the ICSR scores for histology were significantly higher in this group. The expression of aggrecan and type 2 collagen was higher in the group that received complete treatment. Conclusions: Microfractures and transplantation of synovium-platelet rich fibrin (S-PRF) can regenerate knee cartilage defects which have been shown to increase the expression of mRNA aggrecan and mRNA type 2 collagen resulting in excellent repair.
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Reconstruction after en-bloc resection can be challenging in cases of Campanacci grade 3 giant cell tumour of the bone (GCTB) of the distal radius. Here, the authors examined the outcomes of patients with Campanacci grade 3 GCTBs of the distal radius who underwent wrist arthrodesis and reconstruction with ulnar translocation. Material and methods: This case series was a retrospective single-centre study. Clinical assessments regarding the functional status and complications were follow-up. The functional results were evaluated using the Musculoskeletal Tumor Society (MSTS) and Disability of Arm, Shoulder, and Hand (DASH) Score. Paired t-tests were used to compare the MSTS and DASH scores separately before and after the operation. Statistical differences were considered significant at P less than 0.05. Results: Seven patients were included in this study. The mean follow-up period was 14.43±8.08 months. The average length of tumour resection was 9.78±2.88 cm. The average range of motion of the involved forearm was 82.66° of supination and 81.54° of pronation. The average MSTS score was 11.71±2.21 before and 25.14±2.41 after the operation (P<0.05). The average DASH score on admission was 40.14±14.66, which decreased to 9.02±4.23 after the operation (P<0.05). Of the seven cases, one case had a recurrence, and one patient had radioulnar synostosis. Conclusion: Wrist arthrodesis combined with ulnar translocation can be considered a simple and effective reconstruction method with preservation of function after en-bloc resection of Campanacci grade 3 GCTB of the distal radius. It provides good functional outcomes with low complication rates.
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Frozen shoulder (FS) is a disease caused by an inflammatory condition that causes severe pain and decreased range of motion by loss of glenohumeral mobility. Frozen Shoulder restricts daily life's functional aspect, increasing morbidity. Hypertension and diabetes mellitus are risk factors that make an FS poor prognosis during treatment because of the diabetes glycation process and hypertension-enhanced vascularization. Prolotherapy injects an irritant solution into the tendon, joints, ligaments, and joint spaces to release growth factors and collagen deposition, reducing pain, restoring joint stability, and increasing the quality of life. We report 3 cases of patients with confirmed FS. Patient A with no comorbidity, patient B with diabetes mellitus, and patient C with hypertension, with all patient's chief complaints of shoulder pain and limited ROM, and symptoms affected the general quality of daily life. This patient was provided injection with Prolotherapy treatment combined with physical therapy intervention. Patient A had significantly improved ROM to maximum after 6 weeks with relieved pain and improved shoulder function. Patients B and C showed increased ROM, still tiny, decreased pain, and improved shoulder function. In conclusion, prolotherapy demonstrated a beneficial effect in a patient with FS with comorbidities, although not to the maximum extent in patients without comorbidity.
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INTRODUCTION AND IMPORTANCE: Osteoarthritis is a severe joint disease that affects more than 60% of the elderly and more common an idiopathic disease or unknown cause although there is also a secondary cause such as trauma, infection, neurological or metabolic disorders. The usual complaints that perceived by osteoarthritis patients is pain in the affected joint. Many patients and providers think of arthroplasty as the only surgical option for the treatment of osteoarthritis of the knee. However, there are several other surgical options for osteoarthritis which can be therapeutic alternatives. The role of bone marrow stimulation and intraarticular injection with triamcinolone and Hyaluronic acid combination on grade III knee osteoarthritis patient has not been reported. CASE PRESENTATION: Three patients who presented to orthopedic department with complaints of bilateral knee pain were identified with grade III osteoarthritis (Kellgren and Lawrence) receiving some kind of analgetic treatment for more than 1 year which provided pain relief for some time but not permanent. They underwent arthroscopic procedure (bone marrow stimulation) and then injected with triamcinolone and hyaluronic acid combination. Pre and post operation outcome scores (WOMAC score, Interleukin 15 and MRI) were assessed. At six-month follow-up, all patients reported improvement in pain and stiffness. WOMAC score and Interleukin 15 serum level decreases, MRI with Amadeus score showed improvement of cartilage defect. CLINICAL DISCUSSION: This case report showed that our three patients were successfully treated with bone marrow stimulation and intraarticular injection with triamcinolone and hyaluronic acid combination. All three patients have improved in their functional outcome, IL 15 and cartilage defect. CONCLUSION: Bone marrow stimulation and intraarticular injection with triamcinolone and hyaluronic acid combination can be a valuable treatment option for moderate active patients with grade III knee osteoarthritis.
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BACKGROUND Frozen shoulder (FS) is a common conditions that causes significant morbidity. It is characterized by restriction of both active and passive shoulder motion (ROM) of the glenohumeral joint. The etiology, pathology, and most efficacious treatments are unclear. The purpose of FS treatment is complete elimination of pain and recovery of shoulder joint function. Prolotherapy injects certain compounds into articular spaces, ligaments, and/or tendons to relieve pain and disability around joint spaces and to stimulate a proliferation cascade to enhance tissue repair and strength. This case report aims to describe functional outcome changes in 2 patients with FS, comparing prolotherapy combined with physical therapy vs physical therapy only. CASE REPORT We report the cases of 2 patients with confirmed FS. Patient A was 66-year-old man with chief concern of right shoulder pain and limited ROM in the past 3 months, which disrupted daily life, with a visual analog scale (VAS) of 6 out of 10. Patient B was 65-year-old man with chief concern of right shoulder pain and limited ROM in the past 2 months. The symptoms affected his general quality of life, with a VAS of 5 out of 10. Patient A underwent prolotherapy combined with physical therapy and had significantly improved ROM after 2 weeks, with relieved pain and improved shoulder function. Patient B underwent physical therapy only and showed similar ROM and no significant pain improvement. CONCLUSIONS Initial treatment with prolotherapy combined with physical therapy for patients with frozen shoulder achieved fast improvement of active and passive ROM, significantly decreased pain, and improved quality of life compared to physical therapy intervention only.
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Bursite , Proloterapia , Idoso , Bursite/diagnóstico , Bursite/terapia , Humanos , Masculino , Modalidades de Fisioterapia , Proloterapia/efeitos adversos , Qualidade de Vida , Amplitude de Movimento Articular , Dor de Ombro/etiologia , Resultado do TratamentoRESUMO
INTRODUCTION: Giant cell tumor is a type of benign tumor which has the characteristic of rapidly growing and a chance to metastasis. It is however locally aggressive and would typically affect young patients. They commonly present with pain and associated with pathological fracture. PRESENTATION OF CASE: This is an uncommon case of 29 years old male with pathological fracture and giant cell tumor in proximal humerus. A plain radiograph revealed pathological fracture in head of humerus and histopathology examination was consistent with giant cell tumor. The patient had surgical option with en bloc giant cell tumor resection following hemiarthroplasty with cementless endoprosthetic implant for humerus, which aimed to provide a single step surgery without any interval debulking surgery. The patient had achieved bony union between 6 weeks after the surgery and recurrence was not found by the time of the last follow-up. DISCUSSION: Based on Campanacci's classification the tumor is divided into 3 stages. The management of giant cell tumors continues to be one of the most challenging areas in orthopedic oncology. Surgery is the first line option; however, it is depending on the tumor staging and can vary from intralesional curettage to total resection of the tumor. Since the local behavior of giant cell tumors has a high risk of local recurrence, en bloc resection and reconstruction were chosen for these Grade III lesions. CONCLUSION: The aim of this procedure is to preserve the shoulder joint shown satisfaction in a clinical, radiological, functional and esthetic result.
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Deposition of tophus is a common feature in chronic gout; however, signs and symptoms are not always well-pronounced in cases of uncommon sites. We report a case series of three patients, one with an acute locked knee suspected to be meniscus tear or intra-articular loose body, a second case with a lump on the dorsal hand suspected to be a benign lesion, and a third case with a finger flexion deformity with carpal tunnel syndrome; all three cases were later on found out to be tophaceous gout. White chalky monosodium urate crystal deposition was found to be the culprit of the symptoms of the patients.
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BACKGROUND: Injury to the medial collateral ligament (MCL) of the knee joint is the most common ligament injury of the knee. Ligament healing generally takes a long time. Micro-ribonucleic acid (miRNA) is one of the noncoding RNAs and plays a crucial role in physiological function; miRNA (miR)-210 is known as a potent factor of angiogenesis, which is an important initiator of ligament healing. The purpose of this study is to examine the effect of local injection of double-stranded (ds) miR-210 on the healing of the MCL of rat knee joint. METHODS: MCLs of Sprague-Dawley rats were cut transversely. After the fascia and skin were sutured, dsmiR-210 or control dsRNA was injected into the injured site of MCL. At 2 weeks and 4 weeks, histological analysis and immunofluorescence staining of vascular endothelial growth factor, isolectin B4, collagen type 1, and Ki67 as well as a mechanical test were performed. Analysis of complementary deoxyribonucleic acid (cDNA) microarray data was performed at 1 week. RESULTS: Histological analysis showed that parallel fibres in the injured site were organised at 2 weeks and became thicker at 4 weeks in the miR-210-treated group, whereas the injured site in controls was filled with loose fibrous tissues and was thinner than that in the miR-210-treated group. The number of blood vessels in the miR-210-treated group was significantly higher than that in controls (p < 0.05), and vascular endothelial growth factor, Ki67, and collagen type 1 in the miR-210-treated group were intensely expressed in the repaired site as compared to the control group. The mechanical test indicated that the ultimate failure load in the miR-210-treated group was significantly higher than that in the control group at 2 weeks. The cDNA microarray analysis showed significant upregulation of genes related to cell proliferation and cell differentiation, and genes involved in negative regulation of apoptosis. CONCLUSION: This study showed that local injection of dsmiR-210 could accelerate MCL healing in rat, which is likely due to stimulation of angiogenesis at the healing site.
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BACKGROUND: No definite consensus has been reached regarding the optimal technique for graft fixation to the femur in an anterior cruciate ligament reconstruction. The purpose of this study was to evaluate the mechanical strength of two cortical suspension devices which were the TightRope (TR), a new adjustable-length loop device, and the EndoButton (EB), a well-established fixed-length loop device. METHODS: The devices were tested under cyclic and pull-to-failure loading conditions in both an isolated device setup and a specimen setup using porcine femora and bovine flexor tendons. In particular, we examined the influence of tendon and device lengths, whereby the total length of the bone tunnel was fixed to 35 mm and an effective length of tendon in the bone tunnel was adjusted. RESULTS: In the isolated device testing, the EB showed significantly higher ultimate tensile strength than the TR. The displacement after preloading for the EB was statistically lower than that for the TR, and retained a significant difference after the cyclic load. In contrast, specimen testing showed no statistical difference in the displacement among the EB group and TR groups. CONCLUSION: This study indicated that the EB provides greater mechanical strength than the TR. An important new finding was the measurement of initial displacement from the initiation of fixation until loading began using 50 N of tension. In isolated device testing, the TR induced significantly more displacement than the EB during preloading, which could reflect the TR loop's stretching capacity until a certain amount of tension is applied.
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Reconstrução do Ligamento Cruzado Anterior/instrumentação , Teste de Materiais , Dispositivos de Fixação Ortopédica , Animais , Reconstrução do Ligamento Cruzado Anterior/métodos , Bovinos , Desenho de Equipamento , Fêmur/cirurgia , Modelos Animais , Suínos , Tendões/cirurgia , Resistência à TraçãoRESUMO
INTRODUCTION: The important functions of the meniscus are shock absorption, passive stabilization and load transmission of the knee. Because of the avascularity of two-thirds of the meniscal center region, the treatment of tears in this area is hard. Recently, microRNAs have been proven to play an important role in the pathogenesis of diseases. We focused on microRNA (miR)-210, which plays a wide spectrum of roles comprising mitochondrial metabolism, angiogenesis, DNA repair and cell survival. This study aimed to investigate the effect of intra-articular injection of synthetic miR-210 on the injured meniscus in the avascular zone. METHODS: The middle segments of the medial meniscus of Spraque Dawley rats were incised longitudinally with a scalpel. An intra-articular injection of double-stranded (ds) miR-210 (for control group using control dsRNA) with atelocollagen was administered immediately after injury. Four weeks and 12 weeks after the injection, we conducted a histologic evaluation, immunohistochemical evaluation and Real-time PCR analysis. In vitro, the inner meniscus and synovial cells were isolated from rat knee joint, and were transfected with ds miR-210 or control dsRNA. Real-time PCR and immunohistochemical evaluations were performed. RESULTS: Twenty-four hours after the injection, FAM (Fluorescein amidite) labeled miR-210 was observed in the cells around the injured site. Four weeks after the injection, the injured site of the miR-210 group was filled with repaired tissue while that of the control was not repaired. In gene expression analysis of the meniscus, the expression of miR-210, Collagen type 2 alpha 1 (Col2a1), Vascular endothelial growth factor (VEGF), and Fibroblast growth factor-2 (FGF2) in the miR-210 group was significantly higher than that in the control. At 12 weeks, the intra-articular injection of miR-210 had healed the injured site of the meniscus and had prevented articular cartilage degeneration. In vitro, miR-210 upregulated Col2a1 expression in the meniscus cells and VEGF and FGF2 expression in the synovial cells. CONCLUSIONS: An intra-articular injection of ds miR-210 was effective in the healing of the damaged white zone meniscus through promotion of the collagen type 2 production from meniscus cells and through upregulated of VEGF and FGF2 from synovial cells.
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Modelos Animais de Doenças , Meniscos Tibiais/efeitos dos fármacos , MicroRNAs/administração & dosagem , MicroRNAs/síntese química , Lesões do Menisco Tibial , Cicatrização/efeitos dos fármacos , Animais , Injeções Intra-Articulares , Masculino , Meniscos Tibiais/patologia , Ratos , Ratos Sprague-Dawley , Cicatrização/fisiologiaRESUMO
BACKGROUND: It is difficult for an articular cartilage injury to repair spontaneously. There are many procedures for treating cartilage injury, however there is no standard procedure for middle-aged patients who have diffuse knee osteoarthritis, especially of the lateral compartment. Therefore, Ochi developed a new distraction device that uses magnetic power to enlarge a joint space and promote cartilage regeneration with microfracture. The purpose of this study is to evaluate this new distraction arthroplasty system by using the cadaveric knee. METHODS: This study used ten knees from six cadavers that were embalmed by Thiel's methods. The medial and lateral joint space was measured by AP radiographic view before and after distraction, and after weight-bearing to evaluate the joint distraction. The contact pressure of the medial and lateral compartments at the knee extension position by using a prescale film system was measured before and after weight-bearing with a 15 or 30-kg weight-bearing load to evaluate the effectiveness of this device. FINDINGS: The lateral joint space significantly increased from the pre-distraction to the post-distraction; however, it did not change significantly between post-distraction and post-weight-bearing. With a 15 or 30-kg weight-bearing load, the contact pressure of the lateral compartment significantly decreased from the pre-distraction to the post-distraction. INTERPRETATION: The most important advantage of this device is that it maintains a continuous distraction tension and enables almost the full range of motion of the knee. We believe that joint distraction by using magnetic force can be a promising option for cartilage injury in middle-aged patients.