Learning Objectives: After studying this article, the reader should be able to: 1. Define the role of platelets in hemostasis and wound healing. 2. Describe the technologies for platelet concentration and application. 3. Characterize the platelet concentration and growth factor components of platelet-rich plasma. 4. List the potential applications of platelet-rich plasma in plastic surgery and how it may be applied intraoperatively. 5. Discuss the limitations of the use of platelet-rich plasma and its potential complications.Summary: Healing of hard and soft tissue is mediated by a complex array of intracellular and extracellular events that are regulated by signaling proteins, a process that is, at present, incompletely understood. What is certain, however, is that platelets play a prominent if not deciding role. Controlled animal studies of soft and hard tissues have suggested that the application of autogenous platelet-rich plasma can enhance wound healing. The clinical use of platelet-rich plasma for a wide variety of applications has been reported; however, many reports are anecdotal and few include controls to definitively determine the role of platelet-rich plasma. The authors describe platelet biology and its role in wound healing; the preparation, characterization, and use of platelet-rich plasma; and those applications in plastic surgery for which it may be useful.Healing of hard and soft tissue is mediated by a complex array of intracellular and extracellular events that are regulated by signaling proteins, a process that is, at present, incompletely understood.1-5 What is certain, however, is that platelets play a prominent if not deciding role.3,6 Platelet activation in response to tissue damage and vascular exposure results in the formation of a platelet plug and blood clot to provide hemostasis and the secretion of biologically active proteins. These proteins, in turn, set the stage for tissue healing, which includes cellular chemotaxis, proliferation, and differentiation; removal of tissue debris; angiogenesis; and the laying down of extracellular matrix and regeneration of the appropriate type of tissue. 2-4,6 In vitro, there is a dose-response relationship between platelet concentration and the proliferation of human adult mesenchymal stem cells, the proliferation of fibroblasts, and the production of type I collagen.7,8 This suggests that the application of autogenous platelet-rich plasma can enhance wound healing, as has been demonstrated in controlled animal studies for both soft and hard tissues. 9,10

Platelets play a central role in hemostasis and wound healing. The latter is mediated by release of secretory proteins on platelet activation, which directly or indirectly influences virtually all aspects of the wound healing cascade. Studies in basic science have shown a dose-response relationship between the platelet concentration and levels of secretory proteins, as well as between platelet concentration and certain proliferative events of significance to the healing wound. Technologies to provide autologous platelet rich plasma to the repair site are now being used in a wide variety of clinical applications, with the majority of such studies suggesting a role in the surgeon's armamentarium. Little standardization in the field exists, which has made it difficult to fully evaluate the literature on the subject and unequivocally establish applications for which the technology truly has merit. This article presents fundamental background on platelet biology and the role of platelets in both hemostasis and wound healing, as well as methods of preparing, characterizing, and using platelet rich plasma, to provide the reader a foundation on which to critically evaluate prior studies and plan future work.

Bone healing is a complex and multifactorial process. As such, there are numerous steps in the process to which intervention can be directed. This has given rise to many bone graft technologies that have been used to regenerate bone, creating, perhaps, a bewildering array of options. The options that surgeons have the most familiarity with are the ones that have been available the longest (i.e., autograft and allograft). Although useful for the widest spectrum of clinical applications, limitations of these grafts has prompted the development of new materials. Demineralized bone matrix formulations and synthetic ceramic materials are now being used with greater frequency. These biomaterials have demonstrated their usefulness in facial plastic and reconstructive surgery with their ability to augment and replace portions of the craniofacial skeleton. The purpose of this article is to describe and discuss the allograft and alloplastic bone grafting technologies so that the reader can consider each in the context of the others and gain a better appreciation for how each fits into the universe of existing and emerging treatments for bone regeneration.

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In general, the 2.5-mm-diameter LactoSorb copolymer screws provided adequate stability for healing of osteochondritis dissecans lesions and degraded without an inflammatory response by the body.

Demineralized bone matrix (DBM) is a widely used bone graft material that derives its osteoinductive potential from matrix-associated bone morphogenetic proteins (BMPs). Prior investigations have shown that the osteoinductive potential can vary widely, with influence from both donor and processing sources. Although it is plausible that donor variance in the BMP profile can be an important consideration, the few published studies available have given inconsistent and incomplete information about this. The goal was to (1) characterize the variance of BMP-2, BMP-4, and BMP-7 in fully demineralized DBM derived from 20 appropriately screened (Food and Drug Administration and the American Association of Tissue Banks criteria) donors (male and female, 17-65 years) and (2) using literature review, infer the potential for this to be an important source of variability in graft function. BMPs were extracted with 4 M guanidine hydrochloride, and levels of BMP-2, BMP-4, and BMP-7 were measured using enzyme-linked immunosorbent assay. Measured levels were as follows: BMP-2 = 21.4 +/- 12.0 ng/g DBM, BMP-4 = 5.45 +/- 2.04 ng/g DBM, and BMP-7 = 84.1 +/- 34.4 ng/g DBM, which were significantly different (P < 0.05). There was a positive linear correlation between BMP-2 and BMP-7 (P = 0.0227). DBM derived from female donors had significantly greater concentrations of BMP-2 and BMP-7 than did that derived from male donors (P = 0.0257 and 0.0245, respectively). There was no significant correlation between donor age and the levels of any of the measured BMPs. The magnitude of variance of BMP profile appears to reasonably well correspond to the variance in osteoinductive potential cited by others, suggesting the possibility of using this as a method of donor screening.

Platelet treatment appears to improve several short-term outcomes following total knee arthroplasty. Total knee arthroplasty (TKA) is one of the most common orthopedic procedures performed, restoring function and reducing pain in the arthritic knee. 1 In general, results are excellent with reported survival rates as high as 90%-95% at 10-15 year follow-up. 2 Complications are infrequent, with reoperations occurring in approximately 1% of patients per year. 3 With an aging population, elective TKA rates are steadily increasing. In addition, there is a trend toward earlier hospital discharge during a more acute phase of recovery in an effort to reduce hospital costs. 4,5 Consequently, there is great motivation for ensuring expedient postoperative recovery.