摘要:

Complex biologic molecular and cellular processes underlie the structure and function of vertebrate musculoskeletal systems. Improvements in the management of sports or similar orthopedic injuries are possible utilizing biologic interventional methods, including the use of tissues, cells, bioactive molecular agents, and bioabsorbable materials. The various biologic intervention methods can have a beneficial effect on structural, neuromuscular, and physiologic characteristics of damaged musculoskeletal systems. Care must be taken to ensure that any bioactive therapeutic method does not lead to potentially dangerous results, such as harmful neoplasms. Methods designed to work symbiotically with the patient's own unique evolutionarily honed biologic characteristics are likely to result in the ultimate goal of full restoration of musculoskeletal function.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

The persistently high incidence of knee ligament injuries has spurred a growing interest in the biology of ligament healing. Similarly, the recognition that healed ligament tissue is structurally inferior to the intact ligament has focused efforts on potential biologic interventions aimed at improving the quality of healed tissue. A host ofin vitroandin vivostudies have recently begun to elucidate the role of several growth factors in regulating ligament healing in structures such as the medial collateral ligament. Evidence that growth factors may promote cell proliferation and protein synthesis have prompted an interest in gene transfer technology as a means to enhance long-term growth factor expression in injured ligaments. This manuscript will review current knowledge of the effects of growth factors on ligament healing in light of potential biologic interventions.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

In sports injuries, the most commonly injured tissues, including cartilage, tendons, and certain ligaments, are limited in their ability to heal. A number of growth factors show promise as agents that may improve healing, but their potential clinical use is limited by delivery problems. Gene transfer technologies offer new ways to deliver growth factors and other useful products locally, in a sustained fashion, to tissues that have a restricted healing capacity. Gene transfer circumvents problems that result from the relatively short half-lives of the gene products and can be accomplished byin vivoandex vivoprocedures using a variety of different vector systems. Promising preliminary data have been published indicating the feasibility of transferring genes to bone, cartilage, ligament, and tendon. These data permit cautious optimism that gene therapy will be clinically used in the treatment of certain sporting injuries.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Nitric oxide is a small, highly reactive molecule that functions as an intracellular and intercellular messenger molecule and participates in numerous physiologic processes. Nitric oxide plays a role in the basic physiology and metabolism of cartilage, tendon, ligament, muscle, and bone, and is involved in the response of these tissues to injury and in their repair. For example, nitric oxide inhibits proteoglycan synthesis in cartilage, regulates blood flow to skeletal muscle during exercise, and affects collagen synthesis in tendon and ligament. Nitric oxide is also involved in inflammation, which is common after sports injury. Thus, nitric oxide is a fundamental participant in the basic biology of sports-related injury.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Muscle injuries are a challenging problem in traumatology and the most frequently occurring injuries in sports medicine. Even though muscles retain their ability to regenerate after injury, the healing process of muscles after such injuries has been found to be slow and often leads to an incomplete muscle recovery. In an attempt to develop approaches to improve muscle healing after injury, the authors have developed reproducible injury models for muscle contusion, strain, and laceration. The authors show that muscle regeneration occurs after those injuries, but the development of scar tissue greatly limits the natural healing process. It is likely that an enhancement of muscle growth and regeneration can be used to improve muscle healing after injuries. The authors have then identified growth factors that enhance myoblast proliferation and differentiationin vitroand muscle regeneration in the injured muscles, which improves muscle healing after injuries. Furthermore, different gene transfer systems, including cell and gene therapy, have been found successful in delivering genes into injured muscles and may open new opportunities to deliver growth factors and improve muscle healing after lacerations, contusions, and strains.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Biodegradable or bioresorbable implants, primarily polylactic acid, polyglycolic acid, and polydioxanone have recently been used for soft tissue fixation in sports medicine. All three are high molecular weight polymers, which are self-reinforced in most instances. Their advantages include resorption over time, load sharing, elimination of magnetic resonance imaging artifacts, drill-through capabilities for ligament graft revision, multitasking, and little need for implant removal. Adverse effects have included synovitis, foreign body reaction, fistula formation, breakage, and loss of fixation. The length of time until implant degradation is a defining characteristic of the individual material. The mechanical properties decline in advance and parallel to the time of degradation. Material and structural properties can be tailored to clinical requirements during manufacturing. Biodegradable interference screws are being used for clinical applications, including cruciate ligament reconstruction. The meniscus arrow implant is beginning to be evaluated for meniscus repair. Existing biodegradable pins have been applied to the stabilization of osteochondral lesions. One brand, Suretac, has been extensively used in shoulder labral reconstruction because of its ease of use and arthroscopic utility. Biodegradable suture anchors are undergoing clinical evaluation in shoulder reconstruction involving the labrum and rotator cuff. Multitasking of biodegradable implants by incorporating pharmaceuticals or growth factors is a potential use of these implants.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

The bone morphogenetic proteins (BMPs) represent a group of multifunctional mediators that serve specific functions in cell differentiation, proliferation, apoptosis, and organogenesis. These molecules are members of the TGF-β superfamily and have highly conserved structural characteristics. Their role in enhancing bone healing in fracture nonunions and segmental defects is described. The use of recombinant BMP-2 in articular cartilage defects has been shown to accelerate healing and to improve the biochemical characteristics of the repair cartilage. Growth and differentiation factors 5, 6 and 7 (members of the BMP family of proteins) serve as signaling molecules to progenitor cells and induce neotendon and ligament formation. These substances may augment healing upon injection or implantatation into injured areas.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Preserved soft tissues serve as allograft replacements for damaged ligaments and menisci in orthopedic surgery. Currently, the most popular method for preserving or storing soft tissue allografts is freezing. During freezing, cryopreservation is used to preserve cell viability in the grafts, with the goal of transplantation of living native cells in a transplanted allograft. Cell cryopreservation efforts have met with mixed success. Cellular viability in cryopreserved soft tissues has not been high in terms of the percentage of cells originally in the grafts and studies suggest, through comparison of donor and recipient (host) DNA, that all donor cells in the transplanted graft are replaced by host cells within a few months. Nonetheless, based on several clinical studies, cryopreserved soft tissues seem to function reasonably well in many circumstances as replacements for ligaments and menisci. Further research is necessary to achieve the goal of cellular transplantation within the grafts, but the current method of storing and preserving soft tissue allografts seems to provide satisfactory replacement tissues in many cases.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

New techniques for cartilage healing and cartilage grafting have been developed for the treatment of chondral lesions. Microfractures and debridement are recommended for the initial treatment brcause they are low-risk arthroscopic procedures with a high success rate. Perichondral autografts, periosteal autografts, plug autografts, autologous chondrocyte implantation, or osteotomy should be reserved for revision chondral surgery because they are higher-risk procedures. Their success rate is approximately the same as that of the low-risk arthroscopic procedures.

ISSN:1062-8592    

出版商:OVID    

年代:1998

数据来源: OVID