Faculty Bibliography

Plastic surgery is a broad-based discipline with emphasis on areas such as breast, craniomaxillofacial, burn, aesthetic, and hand surgery as well as complex wounds and wound healing. Plastic surgery as a specialty captures a great deal of media attention over many other fields of medicine, so education, training, and credentialing have become an area of national interest. The purpose of this article was to provide information on the organization, basic requirements for training, fellowship, and volunteer opportunities within the specialty

INTRODUCTION: While several studies report that bone morphogenetic proteins (BMPs) and vascular endothelial growth factor (VEGF) can act synergistically to improve bone tissue engineering, others suggest that VEGF inhibits osteogenesis. The purpose of these experiments was therefore to evaluate the effect of dual transfection of these growth factors and potential mechanisms of interaction on gene expression and osteogenesis in vitro and in vivo. METHODS: Marrow-derived mesenchymal stem cells (MSCs) were exposed to recombinant VEGF protein or transfected with adenoviruses encoding BMP2, VEGF, or LacZ in a variety of ratios. Alterations in gene and protein expression in vitro as well as bone formation in vivo were assessed. RESULTS: MSC exposure to AdV-VEGF or recombinant VEGF inhibited BMP2 mRNA expression, protein production, and MSC differentiation. Coculture experiments revealed that BMP2 suppression occurs through both an autocrine and a paracrine mechanism, occurring at the transcriptional level. Compared to controls, cotransfection of VEGF and BMP2 transgenes prevented ectopic bone formation in vivo. CONCLUSION: VEGF is a potent inhibitor of BMP2 expression in MSCs, and supplementation or overexpression of VEGF inhibits osteogenesis in vitro and ectopic bone formation in vivo. Strategies to utilize MSCs in bone tissue engineering therefore require careful optimization and precise delivery of growth factors for maximal bone formation.

Soft-tissue reconstruction of traumatic patella and proximal tibial defects is challenging. Pedicled perforator-based adipocutaneous rotation flaps are a versatile local option as they have axial perfusion and greater freedom of transposition compared with random-pattern flaps, and replace the ideal tissue properties of this anatomic region.Experimental: Anatomic dissections were performed on 15 fresh cadaver legs and location of the dominant perforator measured. Clinical: A retrospective review was conducted at the University of Maryland/R Adams Cowley Shock Trauma Center evaluating patients over a 3-year period.Experimental: Cadaver dissections confirmed a principal perforator at 11.4 +/- 1.6 cm inferior to the patella. This vessel is consistently suitable in length and caliber for large rotation flap design. Clinical: Anterior tibial artery perforator flaps were performed on 4 patients following Gustilo IIIB wounds to the patella and tibial plateau. Two patients had rotation flap reconstructions to salvage failed gastrocnemius muscle flaps. All flaps were successful, however, one patient had overwhelming hardware infection several months later despite successfully healed flap.Local anterior tibial artery perforator flaps based on predictable perforators provide reliable coverage of patella and knee defects, bestowing versatility and flexibility to the reconstructive surgeon's armamentarium.

BACKGROUND AND OBJECTIVE: In the field of bone implant surfaces, the effects of nanoscale modifications have received significant attention. In the present study, bone cell activity on 2 implant surfaces with similar microtopography but distinct chemistry and nanotopography (sandblasted/acid-etched surface as control group, and calcium phosphate (CaP) low impregnated surface (Ossean) as test group, both from Intra-Lock, Boca Raton, FL) were evaluated. STUDY DESIGN: The 2 surfaces were characterized by X-ray photoelectronic spectroscopy (XPS) and scanning electron microscopy (SEM) up to x200,000 magnification. The micrometer level roughness profiles were evaluated by means of computer software. Cell adhesion, proliferation, and alkaline phosphatase activity were assessed with human SaOS-2 osteoblasts and bone mesenchymal stem cells in nonosteogenic culture conditions. RESULTS: The XPS and SEM results showed that the Ossean surface presented low levels of CaP impregnation within the titanium oxide layer and texturization at the nanometer scale (nanoroughness) compared with the control surface. Moreover Ossean surface induced significantly higher cell differentiation levels than the control (P < .01). CONCLUSION: This study showed that both homogeneous nanoroughness and CaP low impregnation differently affected in vitro bone cell behavior compared with the control moderately rough surface with less texturing in the nanometer scale. However, the relative importance of nanotopography and surface chemistry in cell reactions is yet to be determined.

OBJECTIVE: To evaluate the effects of clinically relevant variables on the maximum principal stress (MPS) in the veneer layer of an anatomically correct veneer-core-cement-tooth model. METHODS: The average dimensions of a mandibular first molar crown were imported into CAD software; a tooth preparation was modeled by reducing the proximal walls by 1.5 mm and the occlusal surface by 2.0 mm. 'Crown systems' were composed by varying characteristics of a cement layer, structural core, and veneer solid, all designed to fit the tooth preparation. The main and interacting effects of proximal wall height reduction, core material, core thickness, cement modulus, cement thickness, and load position on the maximum stress distribution were derived from a series of finite element models and analyzed in a factorial analysis of variance. RESULTS: The average MPS in the veneer layer over the 64 models was 488 MPa (range = 248-840 MPa). MPS increased significantly with the addition of horizontal load components and with increasing cement thickness. In addition, MPS levels varied as a function of interactions between: proximal wall height reduction and load position; load position and cement thickness; core thickness and cement thickness; cement thickness and proximal wall height reduction; and core thickness, cement thickness and proximal wall height reduction. CONCLUSION: Rational design of veneered structural ceramics must consider the complex geometry of the crown-tooth system and integrate the influence of both the main effects and interactions among design parameters

BACKGROUND: The supraclavicular artery island flap is a useful regional option in head and neck reconstruction. Previous studies have recorded pedicle length, caliber, and ink injection studies of the supraclavicular artery. This study presents a three- and four-dimensional appraisal of the vascular anatomy and perfusion of the supraclavicular artery island flap using a novel computed tomographic technique. METHODS: Ten supraclavicular artery island flaps were harvested from fresh cadavers. Each flap was injected with contrast media and subjected to dynamic computed tomographic scanning using a GE Lightspeed 16-slice scanner. Static computed tomographic scanning was also undertaken using a barium-gelatin mixture. Images were viewed using both General Electric and TeraRecon systems, allowing the appreciation of vascular territory (three-dimensional) and analysis of perfusion flow (four-dimensional). RESULTS: The entire skin paddle was perfused in the majority (nine of 10) of flaps. One of the flaps was perfused only 50 percent. In this case, the pedicle artery was found to be much smaller than the other flap pedicles. Direct linking vessels and recurrent flow by means of the subdermal plexus were found to convey the flow of contrast between adjacent perforators. This explains how perfusion extends to adjacent perforators by means of interperforator flow, and how perfusion is maintained all the way to the distal periphery of the flap. CONCLUSIONS: Using this imaging technique, the authors elucidated the vascular anatomy of the supraclavicular artery island flap. This study confirms previous clinical findings that the supraclavicular artery island flap is a reliable option and gives surgeons new information for future flap refinement.

BACKGROUND: Bottoming out is a well-known phenomenon described with reduction mammaplasty (RM). To date, the evaluation of post-operative bottoming out remains an imprecise science. The following study reports the application of three-dimensional (3D) photography to objectively investigate changes in breast morphology. METHODS: Patients undergoing medial pedicle RM had 3D photographs (Konica Minolta V910) taken during the early and late post-operative period (early=60-120 days; late=400-500 days). 3D images were compared and bottoming out was assessed with 3D parameters and vectors including total breast volume, volumetric tissue distribution above and below the Central (C) plane, distance of the C-plane to the lowest point of the breast, and maximum anterior-posterior projection from the chest wall. RESULTS: Post-operative images from 15 consecutive RM patients showed an average volume of 556+/-144cm3 (early) and 441+/-183cm3 (late). The percent of tissue in the upper pole of the breast changed from the early to late post-operative period (76% vs. 69%, respectively; p<0.01). The distance from a fixed C-plane to the inferior pole significantly increased (42+/-15mm early vs. 51+/-18mm late; p<0.01). AP projection decreased by an average of 6.23mm (p<0.01). The lateral border of the IMF significantly dropped by 6.27mm. CONCLUSIONS: This study objectively describes both the occurrence of bottoming out and the quantitative amount in terms of changes in volumetric distribution, surface topography and breast projection. With 3D photography, plastic surgeons can perform objective evaluation of breast transformation over time, which ultimately will aid in planning to allow for better surgical outcomes

BACKGROUND: Surgical planning aims to restore coordinated eyelid function. Although achieving voluntary eye closure is one of the primary goals, it cannot guarantee return of involuntary blink. Restoration of the afferent pathway of the reflex is a prerequisite, but successful coordination of the reflex components and restoration of their time-related function are also required. METHODS: A retrospective review of 49 patients who underwent dynamic procedures for blink restoration was performed. The patients were divided into two groups. Group A (n = 42) included patients who underwent nerve transfers: cross-facial nerve grafting and subsequent microcoaptations, mini-hypoglossal nerve transfers, and direct orbicularis oculi neurotization. Group B (n = 14) included patients who underwent eye sphincter substitution techniques: pedicled frontalis, free platysma, mini-temporalis, and a slip of free pectoralis minor transfers. Seven of the patients included in the groups underwent both nerve and muscle transfer procedures. Objective blink ratios were measured according to an established protocol by the senior author (J.K.T.). RESULTS: Thirty patients were girls and 19 were boys. The age of the patients ranged from 1 to 17 years, with a mean +/- SD age of 7.5 +/- 3.2 years. Denervation time ranged from 76 months to 15.25 years. Blink improvement was noted in all of the patients. Blink scores and ratios were consistently better in group A than in group B. CONCLUSION: Dynamic procedures provide the functional potential on which subsequent static procedures can be performed to aid blink return, taking into account the future needs of the still growing patient

High velocity injuries have traditionally been covered with free muscle flaps. We sought to evaluate the utility of the anterolateral thigh flap (ALT) flap as a primary choice in reconstructing traumatic injuries in Western patients.A retrospective chart review was conducted of 122 patients treated at the R Adams Cowley Shock Trauma Center and at the Louisiana State University Trauma Center. Data collected included defect size, donor site location, flap composition and size, number of anastamoses, number of perforators, donor site closure, and complications.A total of 127 ALT flap reconstructions were performed. About 74% involved the lower extremity, 12% head and neck, 11% upper extremity, 2% abdomen, <1% chest, and <1% pelvis. The success rate was 96% with 3 total flap failures and 2 partial flap failures. Average follow-up was 9.3 months.The results of this review confirm that the ALT flap is a reliable, versatile tool for managing composite traumatic injuries.

Vascularized nerve grafts (VNG) were introduced in 1976 but since then, there have been no reports of their usage in lower extremity reconstruction systematically. The factors influencing outcomes as well as a comparison with conventional nerve grafts will be presented.Since 1981, 14 lower extremity nerve injuries in 12 patients have been reconstructed with VNG. Common peroneal nerve was injured in 12 and posterior tibial nerve in 5 patients. The level of the injury was at the knee or thigh. Twelve sural nerves were used as VNG with or without concomitant vascularized posterior calf fascia.All patients regained improved sensibility and adequate posterior tibial nerve function. For common peroneal nerve reconstructions, all patients with denervation time less than 6 months regained muscle strength of grade at least 4, even when long grafts were used for defects of 20 cm or more. Late cases, yielded inadequate muscle function even with the use of VNG.Denervation time of 6 months or less was critical for reconstruction with vascularized nerve graft. Not only the results were statistically significant compared with late cases, but also all early operated patients achieved excellent results. VNG are strongly recommended in traction avulsion injuries of the lower extremity with lengthy nerve damage