One of the most challenging complications in trauma surgery is infection after fracture fixation (IAFF). IAFF may result in permanent functional loss or even amputation of the affected limb in patients who may otherwise be expected to achieve complete, uneventful healing. Over the past decades, the problem of implant related bone infections has garnered increasing attention both in the clinical as well as preclinical arenas; however this has primarily been focused upon prosthetic joint infection (PJI), rather than on IAFF. Although IAFF shares many similarities with PJI, there are numerous critical differences in many facets including prevention, diagnosis and treatment. Admittedly, extrapolating data from PJI research to IAFF has been of value to the trauma surgeon, but we should also be aware of the unique challenges posed by IAFF that may not be accounted for in the PJI literature. This review summarizes the clinical approaches towards the diagnosis and treatment of IAFF with an emphasis on the unique aspects of fracture care that distinguish IAFF from PJI. Finally, recent developments in anti-infective technologies that may be particularly suitable or applicable for trauma patients in the future will be briefly discussed.

As materials technology and the field of biomedical engineering advances, the role of cellular mechanisms, in particular adhesive interactions with implantable devices, becomes more relevant in both research and clinical practice. A key tenet of medical device design has evolved from the exquisite ability of biological systems to respond to topographical features or chemical stimuli, a process that has led to the development of next-generation biomaterials for a wide variety of clinical disorders. In vitro studies have identified nanoscale features as potent modulators of cellular behavior through the onset of focal adhesion formation. The focus of this review is on the recent developments concerning the role of nanoscale structures on integrin-mediated adhesion and cellular function with an emphasis on the generation of medical constructs with regenerative applications. KeywordsFocal adhesions; Biomaterials; Nanotopography; Cell signaling This review highlights the importance and development of the physiomechanical processes that regulate early cell-biomaterial interactions and the influence of nanoscale topographical modification on integrin-mediated cellular adhesion. As materials technology and the field of tissue engineering advance, the role of cellular adhesive mechanisms, in particular the interactions with implantable materials, becomes more relevant in both research and clinical practice.Biomaterials are never truly inert, being at best biotolerable. The cell-substratum interface functions as more than a simple boundary of definition between the host and an implanted device; instead, it presents primary cues for cellular adhesion and the subsequent induction of tissue integration. Indeed, the cytocompatibility of a material can be assessed in vitro by observing the viability and biofunctionality of cells at the substratum interface, paving the way for in vivo studies into device functionality. The range of materials currently designated as biomedically useful and their lack of biofunctionality reflects an increasing need for biomimetic constructs but also indicates the challenges present within the field. In particular a need exists to create truly biocompatible devices and ultimately to control the interactions that occur at the cell-substratum interface.A key tenet of medical device design has evolved from the exquisite ability of biological systems to respond to topographical features or chemical stimuli, a process that has led to the NIH Public Access Author ManuscriptNanomedicine. Author manuscript; available in PMC 2010 October 28. Published in final edited form as:Nanomedicine. 2010 October ; 6(5): 619-633. doi:10.1016/j.nano.2010.01.009. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript development of next-generation biomaterials. Recently published in the journal Science are the prerequisites for third generation biomaterials; not only should they support the healing site (as first-generation biomaterials), but they should be bioactive and possibly biodegradable...

No abstract

No abstract

Mesenchymal stem cells (MSCs) are increasingly being used in tissue engineering and cell-based therapies in all fields ranging from orthopedic to cardiovascular medicine. Despite years of research and numerous clinical trials, MSC therapies are still very much in development and not considered mainstream treatments. The majority of approaches rely on an in vitro cell expansion phase in monolayer to produce large cell numbers prior to implantation. It is clear from the literature that this in vitro expansion phase causes dramatic changes in MSC phenotype which has very significant implications for the development of effective therapies. Previous reviews have sought to better characterize these cells in their native and in vitro environments, described known stem cell interactions within the bone marrow, and discussed the use of innovative culture systems aiming to model the bone marrow stem cell niche. The purpose of this review is to provide an update on our knowledge of MSCs in their native environment, focusing on bone marrow-derived MSCs. We provide a detailed description of the differences between naive cells and those that have been cultured in vitro and examine the effect of isolation and culture parameters on these phenotypic changes. We explore the concept of "one step" MSC therapy and discuss the potential cellular and clinical benefits. Finally, we describe recent work attempting to model the MSC bone marrow niche, with focus on both basic research and clinical applications and consider the challenges associated with these new generation culture systems.