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Development of artificial materials for the facilitation of cartilage regeneration remains an important challenge in orthopedic practice. Our study investigates the potential for neocartilage formation within a synthetic polyester scaffold based on the polymerization of high internal phase emulsions. The fabrication of polyHIPE polymer (PHP) was specifically tailored to produce a highly porous (85%) structure with the primary pore size in the range of 50–170 μm for cartilage tissue engineering. The resulting PHP scaffold was proven biocompatible with human articular chondrocytes and viable cells were observed within the materials as evaluated using the Live/Dead assay and histological analysis. Chondrocytes with round nuclei were organized into multicellular layers on the PHP surface and were observed to grow approximately 300 μm into the scaffold interior. The accumulation of collagen type 2 was detected using immunohistochemistry and chondrogenic specific genes were expressed with favorable collagen type 2 to 1 ratio. In addition, PHP samples are biodegradable and their baseline mechanical properties are similar to those of native cartilage, which enhance chondrocyte cell growth and proliferation.

The ancient Greeks barred women from participating at the ancient Olympics, even as spectators (1). Baron Pierre de Coubertin, the man credited for the birth of the modern Olympics, regarded women's taking part in sports as being "against the laws of nature." To cite his words: "Olympics are solemn and periodic exaltation of male athleticism, with internationalism as a base, loyalty as a means for its setting and female applause as a reward" (2). As a result of this attitude , women did not participate at the first modern Olym-pic games in Athens in 1896. However, a century later at the same place-during the 2004 Olympics, 4329 women from all over the world competed in the majority of 300 official events. Nowadays, taking part in sports is seen a positive experience for women, since it improves physical fitness, enhances self-esteem, and contributes to better physical and mental health. Apart from professional sport, there has also been a dramatic increase in women's sports participation on recreational and amateur level.

The aim of this paper is to report on three cases of symptomatic osteochondritis dissecans of the humeral capitellum in adolescent gymnasts, two females and one male. In all the cases arthroscopic surgery was performed. During arthroscopy, loose osteochondral fragments were removed, the defect was debrided and microfractures were performed. All the three patients regained the full range of motion of the affected elbow, and returned to the high-level gymnastics within a period of 5 months. At 12 months follow-up, all the three patients remained symptomless and were participating in high-level gymnastics. A combination of arthroscopy and the microfracture technique is a reliable method with excellent short-term results in the treatment of the osteochondritis dissecans of the elbow.

Clinical management of delayed healing or nonunion of long bone fractures and segmental bone defects poses a substantial orthopaedic challenge. Surgical advances and bone tissue engineering are providing new avenues to stimulate bone growth in cases of bone loss and nonunion. The reamer-irrigator-aspirator (RIA) device allows surgeons to aspirate the medullary contents of long bones and use the progenitor-rich "flow-through" fraction in autologous bone grafting. Dexamethasone (DEX) is a synthetic steroid that has been shown to induce osteoblastic differentiation. A series of 13 patients treated with RIA bone grafting enhanced with DEX for nonunion or segmental defect was examined retrospectively to assess the quality of bony union and clinical outcomes. Despite the initial poor prognoses, promising results were achieved using this technique; and given the complexity of these cases the observed success is of great value and warrants controlled study into both standardisation of the procedure and concentration of the grafting material.

Cell-based therapy represents a promising treatment strategy for cartilage defects. Alone or in combination with scaffolds/biological signals, these strategies open many new avenues for cartilage tissue engineering. However, the choice of the optimal cell source is not that straightforward. Currently, various types of differentiated cells (articular and nasal chondrocytes) and stem cells (mesenchymal stem cells, induced pluripotent stem cells) are being researched to objectively assess their merits and disadvantages with respect to the ability to repair damaged articular cartilage. In this paper, we focus on the different cell types used in cartilage treatment, first from a biological scientist’s perspective and then from a clinician’s standpoint. We compare and analyze the advantages and disadvantages of these cell types and offer a potential outlook for future research and clinical application.

The purpose of this paper is to review current developments in bone tissue engineering, with special focus on the promising role of nanobiotechnology. This unique fusion between nanotechnology and biotechnology offers unprecedented possibilities in studying and modulating biological processes on a molecular and atomic scale. First we discuss the multiscale hierarchical structure of bone and its implication on the design of new scaffolds and delivery systems. Then we briefly present different types of nanostructured scaffolds, and finally we conclude with nanoparticle delivery systems and their potential use in promoting bone regeneration. This review is not meant to be exhaustive and comprehensive, but aims to highlight concepts and key advances in the field of nanobiotechnology and bone regeneration.