A fibroma of the tendon sheath (FTS) is a rare and less well-known benign soft-tissue tumor. FTS infrequently develop in the knee region. Especially intraarticular FTS of the knee was found in a few case reports. We present a rare case of FTS arising from the infrapatellar plica of the knee in 12-year-old man without a history of specific trauma. Magnetic Resonance Imaging (MRI) and an arthroscopic examination revealed an encapsulated soft tissue mass arising from the infrapatellar plica anterior to the anterior cruciate ligament. The histological diagnosis is FTS in the intraarticular of the knee. To the best of our knowledge, this report is the first reported case of FTS involving the infrapatellar plica of the knee.
Anterior Cruciate Ligament ; Child ; Diagnosis ; Fibroma* ; Humans ; Knee Joint ; Knee* ; Magnetic Resonance Imaging ; Tendons*

Erythema multiforme is an acute cutaneous reaction which manifests as macular patches and edematous papules commonly involving the hands, feet, forearm and mucous membranes. It is thought to be caused by viral and bacterial infections, neoplasms, autoimmune diseases such as rheumatoid arthritis, and also by pharmaceuticals such as sulfonamides, phenytoin, barbiturates, penicillins, carbamazepines. Nonsteroidal antiinflammatory drugs (NSAIDs) have been also reported as a possible cause. However, meloxicam that is a kind of cyclooxygenase-2 selective inhibitor has not been rarely reported as a cause of erythema multiforme. Therefore, we report a case with a review of the literature.
Anti-Inflammatory Agents, Non-Steroidal ; Arthritis, Rheumatoid ; Autoimmune Diseases ; Bacterial Infections ; Barbiturates ; Cyclooxygenase 2 ; Erythema Multiforme* ; Erythema* ; Foot ; Forearm ; Hand ; Mucous Membrane ; Penicillins ; Phenytoin ; Sulfonamides

Tendon and ligament disorders are common and lead to significant disability, pain, healthcare cost, and lost productivity. To study the pathogenesis and management strategies of tendon and ligament injury, appropriate choice and analysis of research models is essential. A number of animal models for tendon and ligament injuries are designed to mimic distinct clinical diseases to better evaluate underlying mechanisms and potential treatments. In this review, we discuss the common methods used for inducing animal models related to tendon and ligament injury as well as the variables for assessing outcome that may be used in animal researchs.
Animal Experimentation ; Animals* ; Efficiency ; Health Care Costs ; Ligaments* ; Models, Animal* ; Tendons* ; Translational Medical Research

Genome editing is a useful research tool essentially applicable to gene therapy in the field of biotechnology, pharmaceutics and medicine. Scientists have developed three types of programmable nucleases for genome editing, and these include: Zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas (CRISPR-associated) system particularly derived from bacterial adaptive immune system. Programmable nucleaseses occur double strand breaks (DSBs) on target strand, and a repair mechanism of DSBs introduces either non-homologous end joining (NHEJ) or homology directed repair (HDR), where the pathway is determined by presence of donor DNA template. In this sense, we can generate gene insertion, gene correction, point mutagenesis and chromosomal translocations via endogenous repair mechanism. However, these nucleases exhibit several discrepancies in the aspects of their compositions, targetable sites, efficiency and other characteristics. Here, we discuss on various characteristics of three programmable nucleases and potential outcomes of DSBs. Acknowledging the distinctions among these programmable nucleases will help scientists to select appropriate tools in genome engineering.
Biotechnology ; Clustered Regularly Interspaced Short Palindromic Repeats ; Deoxyribonuclease I ; DNA ; Genetic Engineering ; Genetic Therapy ; Genome* ; Humans ; Immune System ; Mutagenesis ; Mutagenesis, Insertional ; Tissue Donors ; Translocation, Genetic

The osteoarthritis is being emphasized in South Korea becoming an aged society. It is desirable to use a model that reflects human disease when using an animal model to understand the pathophysiology of osteoarthritis and verify the effective treatment materials. Because naturally occuring osteoarthritis is rare in rodent models, chemical or surgical methods are used to induce diseases. While these methods have the advantages of consistent occurrence and rapid progress of osteoarthritis, it is controversial about whether experimentally-induced osteoarthritis progresses in the same pathophysiology of human disease. The model using injection of chemical materials such as collagenase or monoiodoaceatate in joint space has been widely used. Each method leads to joint damage by chemical joint instability with destruction of articular connective tissue and cartilage cell apoptosis with inhibition of cell metabolism. Anterior cruciate ligament resection model, meniscus resection model, collateral ligament resection model, menisco-tibia ligament resection model and etc. are used as surgical models. These days, it tends to be used menisco-tibia ligament resection model more. It is required to observe the joint damage as well as induction of pain, recently. This review considers how to induce osteoarthritis of knee model used widely, usage of the pathogenesis studies, advantages and disadvantages.
Animals* ; Anterior Cruciate Ligament ; Apoptosis ; Cartilage ; Cartilage, Articular ; Collagenases ; Collateral Ligaments ; Connective Tissue ; Humans ; Joint Instability ; Joints ; Korea ; Ligaments ; Metabolism ; Models, Anatomic ; Models, Animal* ; Models, Chemical ; Osteoarthritis* ; Osteoarthritis, Knee ; Rodentia

PURPOSE: To investigate the feasibility of in vivo cartilage formation by direct injection the chondrogenic undifferentiated human bone marrow-derived mesenchymal stem cells (hBMSCs) mixed with fibrin glue including TGF-beta3. MATERIALS AND METHODS: Chondrogenic differentiation induced hBMSCs for 14 days (control group-2) and undifferentiated hBMSCs combined with TGF-beta3 mixed (experimental group-3) with fibrin glue and fibrin glue only (control group-1) were injected subcutanteously into the back of nude mouse. For evaluation of the cartilage-like tissue formed after 8 weeks after injection, real time PCR, histological analysis and immunohistochemical analysis were used. RESULTS: Control group-1 did not form any visible mass. Control group-2 as well as experimental group-3 could form new cartilage-like tissue which were demonstrated expression of type II collagen by real-time PCR, histology analysis such as H&E staining, MT staining and type II collagen specific immunohistologic analysis. As results, expression of type II collagen was shown in the both groups. CONCLUSION: Our study confirmed that cartilage-like tissues could be formed in subcutaneous layer of nude mouse by direct injection mixed with fibrin glue including TGF-beta3 without chondrogenic-induction of hBMSCs, suggesting that these model could be suitable for preliminary studies or optimizing experiments to evaluate reconstruction of cartilage.
Animals ; Cartilage* ; Chondrogenesis ; Collagen Type II ; Fibrin Tissue Adhesive* ; Fibrin* ; Humans* ; Mesenchymal Stromal Cells* ; Mice ; Mice, Nude ; Real-Time Polymerase Chain Reaction ; Transforming Growth Factor beta3

Localized pigmented villonodular synovitis (LPVNS) is a rare lesion that can affect any joint, although it is most frequently found in the knee. When LPVNS affects the knee, it is usually a single mass of pedunculated appearance. We present a LPVNS occurred from the junction of the anterior horn of the lateral meniscus and the joint capsule in the knee. It detached and then moved at an unusual location, which caused pain, limitation of knee flexion and locking.
Animals ; Horns ; Joint Capsule ; Joints ; Knee* ; Menisci, Tibial ; Synovitis, Pigmented Villonodular*

Synovial hemangioma is a rare benign intraarticular tumor. Synovial hemangioma of the knee joint has unspecific symptoms, which are pain, limitation of motion and hemarthrosis, often seen as an internal derangement of the knee. A 24-year-old woman presented with intermittent joint effusion and pain of the left knee joint and physical examination revealed slight atrophy of the quadriceps and tenderness around lateral joint line of knee. The patient was performed arthroscopic surgery due to synovial hemangioma about 17-years ago. Magnetic resonance imaging (MRI) showed the synovial hemangioma from Hoffa fat pad to anterior aspect of lateral meniscus, and thus surgical treatment was planned. Arthroscopic excision was performed and additional lesion was observed in lateral gutter, suprapatellar pouch of the knee. The biopsy confirmed the diagnosis of synovial hemangiomas. After 3 year, the patient was completely asymptomatic and showed no signs of recurrence.
Adipose Tissue ; Arthroscopy ; Atrophy ; Biopsy ; Diagnosis ; Female ; Hemangioma* ; Hemarthrosis ; Humans ; Joints ; Knee Joint ; Knee* ; Magnetic Resonance Imaging ; Menisci, Tibial ; Physical Examination ; Recurrence ; Young Adult

Ligamentum flavum (LF) is yellowish ligament tissue connecting the lamina of adjacent vertebra. Degenerative changes in the spine cause the hypertrophy of LF and facet joint and disc bulging and herniation. These changes results in a narrowing of the spinal canal. Neural decompression surgery by removing the hypertrophied lamina, LF and disc pathologies has been considered as successful treatment method in lumbar spinal stenosis. This surgery has showed relatively satisfactory clinical results and has increased life-expectancy in elderly patients. However, issues about post spinal surgery syndrome and re-stenosis after the surgery also have been reported. Because LF is one of the main mechanisms of spinal stenosis, accurate understanding about pathologic mechanism on the LF hypertrophy may suggest alternative treatment methods such as medical treatment or less invasive treatment than surgical decompression can be considered. Hypertrophy of the ligamentum flavum is generated from increase of collagen synthesis, fibroblast proliferation, and fibrosis caused by 1) the expression of growth factors (TGF-beta1 etc.) stimulated by the repeated mechanical tension, 2) inflammatory cytokines from spinal facet joint structure and LF 3) delayed cell death, and 4) inflammatory cytokine from hypertrophied and degenerated LF itself. After the middle ages, gradual and partial inhibition of LF hypertrophy can be expected by administration NSAIDs or selective cyclo-oxygenase-2 inhibitors because these drugs may cause reduction of the increased cytokines. Also, relaxin can be another new treatment material for spinal stenosis by the mechanism of melting hypertrophied LF and reducing synthesis of collagen.
Aged ; Anti-Inflammatory Agents, Non-Steroidal ; Cell Death ; Collagen ; Cytokines ; Decompression ; Decompression, Surgical ; Fibroblasts ; Fibrosis ; Freezing ; Humans ; Hypertrophy* ; Intercellular Signaling Peptides and Proteins ; Ligaments ; Ligamentum Flavum* ; Pathology ; Relaxin ; Spinal Canal ; Spinal Stenosis ; Spine ; Zygapophyseal Joint

Articular cartilage lesions can be a debilitating disease resulting in the development of osteoarthritis (OA). In recent years, mesenchymal stem cell (MSC) strategies combined with the microfracture technique are emerging as a powerful tool for cartilage repair. Even though there are some successful reports of MSCs treatments, many aspects have to be optimized such as best cell source and application method. The interest in this field is growing and randomized controlled trials are needed to show the potential of MSC treatment.
Cartilage ; Cartilage, Articular* ; Mesenchymal Stromal Cells* ; Osteoarthritis