Operative Techniques in Orthopaedics RSS feed: Current Issue. Operative Techniques in Orthopaedics is an innovative, richly illustrated resource that keeps practitioners informed of significant advances in all areas of surgical management. Each issue of this atlas-style journal explores a single topic, often offering alternate approaches to the same procedure. Its current, definitive information keeps readers in the forefront of their specialty.http://www.optechorthopaedics.com/?rss=yesElsevier Inc.en © 2010 Published by Elsevier Inc. All rights reserved. Operative Techniques in Orthopaedics1048-6666202June 2010 © 2010 Published by Elsevier Inc. All rights reserved. healthpermissions@elsevier.comhttp://www.optechorthopaedics.com/article/PIIS1048666610000236/abstract?rss=yesEditorial Board10.1053/S1048-6666(10)00023-6Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9iihttp://www.optechorthopaedics.com/article/PIIS1048666610000248/abstract?rss=yesTable of Contents10.1053/S1048-6666(10)00024-8Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9iiiihttp://www.optechorthopaedics.com/article/PIIS104866661000025X/abstract?rss=yesContributors10.1053/S1048-6666(10)00025-XOperative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9iiiivhttp://www.optechorthopaedics.com/article/PIIS1048666609001670/abstract?rss=yesIn the last decade, the field of orthopaedic surgery has benefited from many advances in musculoskeletal research that have occurred under the rubric of tissue engineering. In the past, tissue engineering has been defined as “an interdisciplinary field that applies the principles of engineering and life sciences toward the development of biological substitutes that restore, maintain, or improve tissue function or a whole organ.” More recently, particularly with the increasing use of stem cells in the role of repairing or replacing tissues, the term regenerative medicine has become to be used almost synonymously with tissue engineering. In fact, a recent NIH definition would suggest that the two terms could both be used to describe a multidisciplinary field involving the life, physical, and engineering sciences that seeks to develop functional cell, tissue, and organ substitutes to repair, replace, or enhance biological function that has been lost due to congenital abnormalities, injury, disease, or aging. This is would include the use of biomaterials or scaffolds, cell sources, biomolecules, engineering methodology, functional assessment, and informatics.IntroductionMorey S. Moreland10.1053/j.oto.2009.11.001Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-96969http://www.optechorthopaedics.com/article/PIIS1048666609001657/abstract?rss=yesHistorically, departments of Orthopaedic Surgery have led new and innovative research in many different fields. Cartilage research is one of those that the Department of Orthopaedic Surgery at the University of Pittsburgh has pioneered since the foundation of the Ferguson Laboratory more than 50 years ago with many marvelous scientists and clinicians having conducted extraordinary research that still affect today's cartilage research. Nowadays, the department has 14 orthopaedic laboratories of different disciplines with over 150 people and 30 faculty members that continue to contribute to our understanding of cartilage injury and degenerative disease.Fifty Years of Cartilage Research in Pittsburgh—A Department's Contribution to Cartilage Tissue EngineeringVerena M. Schreiber, Carola F. van Eck, Wei Shen, Freddie H. Fu10.1053/j.oto.2009.10.012Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-97075http://www.optechorthopaedics.com/article/PIIS104866660900144X/abstract?rss=yesThe limited repair potential of human articular cartilage contributes to development of debilitating osteoarthritis and remains a great clinical challenge. This has led to evolution of cartilage treatment strategies from palliative to either reconstructive or reparative methods in an attempt to delay or “bridge the gap” to joint replacement. Further development of tissue engineering-based cartilage repair methods have been pursued to provide a more functional biological tissue. Currently, tissue engineering of articular cartilage has 3 cornerstones; a cell population capable of proliferation and differentiation into mature chondrocytes; a scaffold that can host these cells, provide a suitable environment for cellular functioning, and serve as a sustained-release delivery vehicle of chondrogenic growth factors; and finally, signaling molecules and growth factors that stimulate the cellular response and the production of a hyaline extracellular matrix. The aim of this review is to summarize advances in each of these 3 fields of tissue engineering, with specific relevance to surgical techniques and technical notes.Advances in Tissue Engineering Techniques for Articular Cartilage RepairAmgad M. Haleem, Constance R. Chu10.1053/j.oto.2009.10.004Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-97689http://www.optechorthopaedics.com/article/PIIS1048666609001682/abstract?rss=yesFibrin has been used in medicine for nearly 100 years and the use of fibrin clots have been used in meniscal repairs for over 20 years. It is theorized that the concentrated levels of platelets in fibrin clot aid in healing through the release of growth factors. The use of concentrated platelets has gained recent popularity through the increase use of platelet-rich plasma; however, it is still unknown what platelet concentration constitutes an optimal level of healing. Recent studies on the healing of the anterior cruciate ligament (ACL) reconstruction and repair suggest that concentrated platelets might play a role in advanced healing in the ACL. This article will summarize the history of fibrin clots in surgery, the biochemistry of platelets, current use, and the future of fibrin clots as biological aids in healing. Techniques for preparing an exogenous clot, repairing meniscal tears with a fibrin clot, and the use of fibrin clots in ACL reconstruction will also be discussed.Use of Fibrin Clot in the KneeKenneth D. Illingworth, Volker Musahl, Stephan G.F. Lorenz, Freddie H. Fu10.1053/j.oto.2009.11.002Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-99097http://www.optechorthopaedics.com/article/PIIS1048666609001463/abstract?rss=yesFor over 20 years, autologous blood products such as platelet-rich plasma (PRP) have been employed as a means to facilitate the healing process in fields such as orthopedics, dentistry, neurosurgery, cardiothoracic, and maxillofacial surgery. Proponents of this therapy advocate its effectiveness as a safe and natural way to expedite the healing process. Recent investigations of the specific growth factors present in PRP advocate its promise as an emerging therapy at the clinical level. However, there exist few controlled trials to objectively examine the proposed benefits of this therapy. Although some studies demonstrate promising results, the bulk of published data are largely anecdotal and the sample sizes are small. This article reviews the biological mechanisms by which PRP facilitates healing as well as the current clinical research that has investigated PRP therapy as a treatment for musculoskeletal injuries, such as tendonitis, tennis elbow, rotator cuff repair, Achilles tendon repair, muscle injuries, bone injuries, and anterior cruciate ligament repair. The increased prevalence of PRP therapy in treating musculoskeletal injuries warrants a more thorough investigation of its actual benefits if we are to endorse it as an effective therapy.Application of Platelet-Rich Plasma to Enhance Tissue RepairAndrew P. Wroblewski, Hector A. Mejia, Vonda J. Wright10.1053/j.oto.2009.10.006Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-998105http://www.optechorthopaedics.com/article/PIIS1048666609001475/abstract?rss=yesMost connective tissue cells (eg, tendon and ligament cells) attach to extracellular matrix and exert so-called cell traction forces (CTFs) on the extracellular matrix. CTFs are essential for many cellular functions, such as maintenance of cell shape, cell motility, and cell communication. Therefore, many techniques have been developed over the years to measure CTFs to better understand tissue physiology and pathology. This article provides a brief review of CTF in terms of its generation and transmission and also CTF measurement techniques, with a focus on CTF microscopy (CTFM). Examples of using CTFM to determine CTFs are given to illustrate various applications of CTFM. Finally, the potential applications of CTFM in musculoskeletal research are suggested.Cell Traction Forces (CTFs) and CTF Microscopy Applications in Musculoskeletal ResearchJames H.-C. Wang10.1053/j.oto.2009.10.007Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9106109http://www.optechorthopaedics.com/article/PIIS1048666609001438/abstract?rss=yesFibrosis is the result of an excessive amount of fibrous connective tissue deposited into the extracellular matrix space of damaged tissues from injury or disease. Collagens, particularly types I and III are the main constituents of the fibrotic scar tissue as well as a mixture of fibrotic cells. Fibrotic tissue will develop chronic healing problems severely resulting in tissue/organ dysfunction. More attention needs to be given to the fibrotic differentiation and related effects in bioengineered tissues. The current review provides an update on the mechanism behind fibrosis formation as well as technical measurements and preventions.Mediators Leading to Fibrosis—How to Measure and Control Them in Tissue EngineeringXiaodong Mu, Ian H. Bellayr, Thomas J. Walters, Yong Li10.1053/j.oto.2009.10.003Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9110118http://www.optechorthopaedics.com/article/PIIS1048666609001669/abstract?rss=yesThe management and treatment of orthopaedic injuries has improved greatly over the last two decades, with the advent of minimally invasive operative techniques and sophisticated rehabilitation augmented by the always increasing knowledge of tissue biology and biomechanics. Despite the progress, scientists and orthopaedic surgeons continue to struggle with the limited healing capacity of damaged structures, such as degenerated articular cartilage, injured skeletal muscle, atrophic fracture nonunion, inflammatory conditions, and aging tissues. Therapeutic approaches that address the underlying pathophysiology of these disorders at the cellular and molecular level are quickly becoming a clinically applicable reality. Rapidly evolving field of stem cell therapy and gene therapy became integral part of regenerative medicine. Researchers have isolated and thoroughly characterized a population of skeletal muscle-derived stem cells (MDSCs) that display improved regenerative capacity in various tissues of the musculoskeletal system, when compared with skeletal myoblasts. These cells can be used to regenerate bone and articular cartilage, skeletal and cardiac muscle; they can repopulate bone marrow and repair peripheral nerve structures. Although the true origin of MDSCs remains unclear, their high degree of similarity with blood vessel–derived stem cells suggests their potential origin could be from the vascular wall. Here, we review the current knowledge concerning the use of gene therapy and tissue engineering applications based on MDSCs to improve the healing of various tissues of the musculoskeletal system, including bone and articular cartilage, as well as injured and diseased skeletal muscle.Regenerative Medicine Based on Muscle-Derived Stem CellsJohnny Huard, Burhan Gharaibeh, Arvydas Usas10.1053/j.oto.2009.10.013Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9119126http://www.optechorthopaedics.com/article/PIIS1048666609001505/abstract?rss=yesStem cell therapy and tissue engineering offer great potential for the treatment of a variety of musculoskeletal disorders. However, the study of stem cells is challenged to identify the most robust cells and control the fate of those cells. Live cell imaging is a tool that offers a high-throughput approach to studying a number of cell types and conditions to help elucidate cells and reagents, which are most functional for treating injuries of bone, cartilage, muscle, or tendon/ligaments. In vitro time-lapsed microscopic imaging of living cells is an efficient approach to generating large datasets on dynamic stem cell behavior. This report describes the live cell imaging tools and their use to observe and track unique stem cell activities. The novel aspect of these systems include automation of imaging by robotic movement of cell culture flasks, which enables selection of a large number of regions of interest for data collection. Standard to most such systems is an environmentally controlled chamber to maintain experimental conditions, including temperature, gas levels, and humidity, so that stem cells can be tracked by visible and epifluorescence imaging over extended periods. These systems offer the capability to overcome limitations associated with scarcity of stem cells, or frequency of events, such as myotube contraction. They can be used to examine fluxes in mitochondrial membrane potential, or create dynamic coculture environments where individual subpopulations can be identified. In this report, we provide an example of the system's use to identify donor cell variability using human umbilical cord mesenchymal stem cells. We describe automation in time-lapsed microscopic imaging and how this technology is providing new insights into stem cell biology.Tracking Stem Cell Function with Computers Via Live Cell Imaging: Identifying Donor Variability in Human Stem CellsBridget M. Deasy, Steven M. Chirieleison, Ashley M. Witt, Matthew J. Peyton, Taylor A. Bissell10.1053/j.oto.2009.10.010Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9127135http://www.optechorthopaedics.com/article/PIIS1048666609001645/abstract?rss=yesUnlike most conventional medicines to treat musculoskeletal disorders, gene therapy focuses on replacing and correcting defective gene. On the basis of evidences of the long-term efficient therapeutic gene expression in the muscle, the recombinant adeno-associated viral (rAAV) vectors are used in the treatment of many life-threatening diseases, especially muscle diseases. The clinical trials for muscle diseases, such as Duchenne muscular dystrophy began 3 years ago. However, the challenges, such as host cytotoxic T lymphocyte response to the vector caspid or/and transgene product are found to interfere with the successful outcome of the rAAV-mediated gene therapy. Further investigation in mechanism and risks associated with immune responses in human as well as a well-designed monitoring plan in clinical trials are essential to achieve the goal of efficacy and safety of the rAAV vectors in clinical trials. Scientists are looking to the novel strategies to optimize the rAAV vectors as a treatment option for human muscle diseases. This review summarizes the development of the rAAV vectors and the treatment of muscular dystrophy by using the rAAV vectors.Gene Therapy and Muscles: The Use of Adeno-associated Virus—Where are We Today?Bing Wang10.1053/j.oto.2009.10.011Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9136143http://www.optechorthopaedics.com/article/PIIS1048666609001499/abstract?rss=yesIntervertebral disc degeneration (IDD) is a condition that is very prevalent throughout the world and is a leading cause of back pain. The socioeconomic burden that back pain has imparted on our health care system and economy cannot be overstated. Current surgical treatment modalities address disrupted biomechanics and pain and not the underlying pathophysiology of disease, resulting in suboptimal outcomes. With advances in cellular and molecular biology, disc tissue engineering and regenerative medicine have emerged as new options. Biological treatments could potentially address the imbalance between catabolism and anabolism that results in disc degeneration, and thus could augment or potentially reverse the course of IDD. The role of tissue engineering, stem cells, and gene therapy has not been completely realized; therefore, continued in vivo studies are required for clinical translation. This article reviews intervertebral disc anatomy and physiology, as well as regenerative medicine concepts, advancements, and challenges facing clinical application.A Change in Strategy: The Use of Regenerative Medicine and Tissue Engineering to Augment the Course of Intervertebral Disc DegenerationBarrett I. Woods, Gwendolyn Sowa, Nam Vo, James D. Kang10.1053/j.oto.2009.10.009Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9144153http://www.optechorthopaedics.com/article/PIIS1048666609001451/abstract?rss=yesThe use of orthobiologics in shoulder surgery is one of the largest areas of growth in the orthopaedic surgery product market. Bone products can fill voids, enhance healing, and provide support. Soft tissue products include scaffolds and products that augment the cell based and factor based healing response. This article focuses on scaffolds and biological augmentations. In the scaffold section, engineered products as well as solutions that use natural tissue will be discussed. In the biological augmentation sections, we will concentrate on products that enhance osteoinduction, angiogenesis, and the cellular response. Scaffolds can augment the mechanical properties of repaired tendons and especially so when the scaffold is constructed from poly-glycolic acid and poly-l-lactic acid. The original polymer material, poly-tetra-fluoro-ethylene, seems to be too mechanically weak for use in the shoulder; the same is true for chitin. Porcine small intestinal submucosa, while once promising, has been exposed as a poor material for scaffold development. Dermal matrix has many questions remaining before its use can be supported. As the field of polymer based molecular delivery continues to develop, we expect the synthetic polymers to continue to dominate the discussion. Many molecular therapies show promise for changing the way the shoulder heals and altering the mechanical properties of the repaired shoulder. Bone morphogenic proteins have shown an ability to affect the formation of the bone-tissue interface. Platelet-rich-plasma and fibrin clots both are promising inductors of angiogenesis, as are low intensity pulsed ultrasound and shock wave therapy. Finally, muscle and bone derived stem cells may potentially have a positive effect on the healing process.Use of Matrices as a Tissue Substitute in Shoulder SurgeryZach Working, Robin V. West10.1053/j.oto.2009.10.005Operative Techniques in Orthopaedics 20, 2 (2010)2010-06-01Operative Techniques in Orthopaedics2010-06-01202S1048-6666(10)X0003-9154160