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Reduction and Fixation of Sacroiliac joint Dislocation by the Combined Use of S1 Pedicle Screws and an Iliac Rod
Published in Kai-Uwe Lewandrowski, Donald L. Wise, Debra J. Trantolo, Michael J. Yaszemski, Augustus A. White, Advances in Spinal Fusion, 2003
Kai-Uwe Lewandrowski, Donald L. Wise, Debra J. Trantolo, Michael J. Yaszemski, Augustus A. White
through direct injection of the unmodified bone marrow into a fracture nonunion site. They have also been used in articular cartilage repair through the process of osteochondral picking. The number of stem cells obtained through this type of harvest depends upon the age of the patient, the aspiration site, and the presence of systemic disease. In using stem cells for tissue engineering purposes, a purified population is desired, so additional processing is performed on the raw bone marrow aspirate. There is approximately one MSC for every 100,000 nucleated marrow stromal cells in a young, healthy donor. These cells can be separated, and purified, from the raw aspirate by taking advantage of their intrinsic adhesive properties. Essentially, stem cells adhere to tissue culture polystyrene, a common tissue culture substrate, while cells of the hematopoietic lineage do not. Thus, a relatively pure population of MSCs can be obtained from a raw bone marrow aspirate by simply allowing the cells to adhere to a tissue culture plate and rinsing away the nonadherant cells [7].
Methods for Evaluating Articular Cartilage Quality
Published in Kyriacos A. Athanasiou, Eric M. Darling, Grayson D. DuRaine, Jerry C. Hu, A. Hari Reddi, Articular Cartilage, 2017
Kyriacos A. Athanasiou, Eric M. Darling, Grayson D. DuRaine, Jerry C. Hu, A. Hari Reddi
Arthroscopy is the most commonly performed orthopedic procedure in the United States (Figure 5.8). It is minimally invasive, although the joint capsule must be compromised. A small (e.g., 5 mm) port is opened in the joint, and optical, surgical, and other instrumentation are introduced through this port. Arthroscopy can be used not only for imaging but also for a variety of surgical procedures, such as meniscus, anterior cruciate ligament, and articular cartilage repair. Cartilage restoration procedures that can be performed arthroscopically include debridement, various marrow stimulation techniques, and the application of scaffolds intended for cartilage repair.
A comprehensive review of sustainable approaches for synthetic lubricant components
Published in Green Chemistry Letters and Reviews, 2023
Jessica Pichler, Rosa Maria Eder, Charlotte Besser, Lucia Pisarova, Nicole Dörr, Martina Marchetti-Deschmann, Marcella Frauscher
A hydrogel is a macromolecular polymer, which can absorb large amounts of fluids within its interstitial space while remaining insoluble in water due to present physical or chemical cross-linking. Biomimicry refers to biological methods and systems found in nature, typically environmentally friendly, that is emulated by modern engineering and technology design. Biomimetic lubrication is often used in the sense of water-based lubrication as in bio-tribology (5). In general, hydrogels are used as biomimetic lubricating materials in biomedical applications such as drug delivery (76) and tissue engineering, for example, for articular cartilage repair, since they show good biocompatibility, viscoelasticity, permeability, and therefore, biomimetic properties, but lack in friction and wear properties (77, 78). They can be synthesized from plant-derived materials including cellulose, hemicellulose, lignin, polysaccharides (starch, pectin, gum), and proteins (76).
Influence of extracellular cues of hydrogel biomaterials on stem cell fate
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Haley Barnett, Mariya Shevchuk, Nicholas A. Peppas, Mary Caldorera-Moore
Another commonly used natural polymer in tissue engineering is hyaluronic acid (HA). HA is a polysaccharide found naturally in the ECM which is one reason it is a popular material in tissue engineering [50,52,54]. However, HA can be degraded by hyaluronidase, naturally found in tissues, and suffers from low mechanical strength [52,55,56]. Alginate has been studied in regenerative medicine for applications such as cell encapsulation, drug stabilization, transplantation of chondrocytes, hepatocytes, and islets of Langerhans to treat diabetes [41,57]. Unfortunately, it is hard to control swelling behavior and tends to rapidly degrade due to ion loss [41,58]. The final natural polymer of note is chitosan. Chitosan has a high molecular weight and is the second most abundant biopolymer found in crustacean shells and fungi cell walls [59]. It is structurally similar to glycosaminoglycans and has been studied for bone regeneration, articular cartilage repair, and most notably for wound dressings [52,59,60]. This information is summarized in Table 1. While natural polymers show great potential for tissue engineering applications due to their similarity to the natural ECM, the main concern with their use is the possible immunogenicity due to their source. Some of these materials are harvested from other species and there is concern for an immune response using materials from a different origin [41,43].
Natural Polymeric Scaffolds for Tissue Engineering Applications
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Lin et al. [149] fabricated two bi-layered biomimetic collagen—PVA nanofibers for the superficial and transitional zones of an articular cartilage. The aligned collagen-based composite was more suitable for articular cartilage repair than the random composite because the former possessed higher tensile strength on its’ surface with a high wear resistance. This tensile strength is due to the > 90% collagen 11 in the collagen component of articular cartilage. This significant difference in tensile properties between the composites has been similarly reported for other materials such as collagen, polycaprolactone and PLGA [150,151]. This demonstrates that the culture of primary articular chondrocytes enhanced tensile properties in direction of the ligaments. Although the tensile strength and Young’s modulus of both composites increased (p < 0.05) after three weeks of chondrocyte culture, the aligned composite had a 0.35MPa Young’s modulus which was similarly reported in the literature. The former implied that related amounts of glycosaminoglycan and collagen 11 were secreted by the chondrocytes present in both composites. For instance, Bandeiras et al. [152] reported 0.364 MPa as the Young’s modulus of human neo-cartilage, while Athanasiou et al. [153] reported the mechanical properties of range 0.45MPa to 0.55MPa when they estimated same properties of neo-cartilage and of thawed bovine, canine, human, monkey and rabbit knee, as well. Finally, the biomimetic nature of the bi-layered aligned composite was demonstrated in its’ biocompatibility (Figure 3).