Howard D. Wang

Incisional negative-pressure wound therapy versus conventional dressings following abdominal wall reconstruction: a comparative study.

BackgroundImprovements in surgical techniques have allowed us to achieve primary closure in a high percentage of large abdominal hernia repairs. However, postoperative wound complications remain common. The benefits of negative-pressure wound therapy (NPWT) in the management of open abdominal wounds are well described in the literature. Our study investigates the effects of incisional NPWT after primary closure of the abdominal wall. MethodsA retrospective chart review was performed for the period between September 2008 and May 2011 to analyze the outcomes of patients treated postoperatively with incisional NPWT versus conventional dry gauze dressings. Patient information collected included history of abdominal surgeries, smoking status, and body mass index. Postoperative complications were analyzed using &khgr;2 exact test and logistic regression analysis. ResultsFifty-six patients were included in this study; of them, 23 were treated with incisional NPWT, whereas 33 received conventional dressings. The rates of overall wound complications in groups I and II were 22% and 63.6%, respectively (P = 0.020). The rates of skin dehiscence were 9% and 39%, respectively (P = 0.014). Both outcomes achieved statistical significance. Rates of infection, skin and fat necrosis, seroma, and hernia recurrence were 4%, 9%, 0%, and 4% for group I and 6%, 18%, 12%, 9% for group II, respectively. ConclusionsThis study suggests that incisional NPWT following abdominal wall reconstruction significantly improves rates of wound complication and skin dehiscence when compared with conventional dressings. Prospective, randomized, controlled studies are needed to further characterize the potential benefits of this therapy on wound healing after abdominal wall reconstruction.

Effects of denosumab treatment and discontinuation on human growth plates.

CONTEXT Denosumab is a humanized monoclonal antibody to receptor activator of nuclear factor-κB ligand used primarily for postmenopausal osteoporosis and skeletal-related events from metastatic cancer. Its safety in children has not been established. OBJECTIVE The objective of the study was to investigate the effects of denosumab treatment on skeletal growth and histology. DESIGN This was an observational case report with radiological and histopathological analyses. SETTING The study was conducted at a clinical research center. PATIENTS A 9-year-old boy with fibrous dysplasia treated with a 7-month course of denosumab participated in the study. INTERVENTION Histological analyses were performed and compared on growth plates from limbs that had been amputated before and 17 months after denosumab treatment. MAIN OUTCOME MEASURES Skeletal radiographs and bone histopathology from before and after treatment were measured. RESULTS After initiating denosumab, sclerotic metaphyseal bands appeared on radiographs. Posttreatment radiographs revealed migration of the bands away from the growth plates, consistent with continued linear growth. Histologically, the bands were composed of horizontally arranged trabeculae containing calcified cartilage. This cartilage appeared to derive from unresorbed primary spongiosa as a result of osteoclast inhibition by denosumab, similar to what has been observed with bisphosphonates. By 17 months after treatment, active bone resorption and formation had returned, as evidenced by the presence of active osteoclasts in resorption pits and osteoid surfaces. CONCLUSIONS Further studies are needed to determine the safety of denosumab on the growing skeleton. However, in this child there was continued epiphyseal activity both during and after treatment and reversal of bone turnover suppression after treatment discontinuation, suggesting that denosumab did not have significant adverse effects on growth.

Aesthetic and functional facial transplantation: a classification system and treatment algorithm.

Background: As of July of 2013, 27 facial vascularized composite allotransplantations have been performed. The authors developed a classification system and treatment algorithm that is practical and surgically applicable. Methods: The majority of the transplants have been described in the surgical literature and the media, and a review of the data was performed. A classification system and a treatment algorithm were designed. Skeletal defects were defined by craniofacial osteotomies and soft-tissue defects by aesthetic facial subunits. The soft-tissue defect was subdivided into the following subunits: oral-nasal (type 1), oronasal-orbital (type 2), and full facial (type 3). The bony defects were subdivided into mandibular involvement (M), Le Fort 1 (A), Le Fort 3 (B), and monobloc (C). Results: The mechanisms of injury included trauma (n = 13), burns (n = 8), congenital deformity (n = 3), oncologic resection (n = 1), and unreported (n = 2). According to the proposed classification system: one was type 1; one was type 1-M; one was type 1-MB; two were type 2; two were type 2-B; two were type 2-MB; six were type 3; one was type 3-B; and three were type 3-MB; eight could not be classified due to a lack of data. The treatment algorithm designed a vascularized composite allotransplantation that addressed the bony and soft-tissue components. Conclusions: Patient selection for these complicated procedures, currently dependent on lifelong immunosuppression, is crucial to their success. The authors describe a classification system and treatment algorithm for facial defects that may be ideally suited for facial transplantation. The proposed classification and algorithm may help centers define indications and ideally improve patient outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

A Novel Method for the Repair of Critically Sized Bone Defects: Utilization of a Muscle Derived Stem Cell-Seeded Scaffold Augments Proliferation, Migration and Osteogenic Induction.

PURPOSE: Contemporary surgical reconstruction of large craniofacial defects, commonly suffered during trauma and lifesaving decompressive craniectomies, has seen tremendous evolution with the development of custom alloplast implants and rigid fixation elements. Although these implants and fixation devices are often capable of providing coverage and stabilization to smaller or less complex defects, they remain prone to infection, extrusion, migration and failure with larger complicated wounds. Within this study, we aim to assess the functionality and osteo-inductive capacity of an easily deliverable osteo-enriched scaffold construct containing hBMP-2 and traceable muscle derived stem cells (MDSCs). We hope to determine a pragmatic regenerative application of this system to civilian and military patients suffering from complex craniofacial defects which current methods cannot address. METHODS: Utilizing a murine model, C57BL/6 (n=60) mice received two identical 5mm full-thickness craniectomy defects using a standardized micro-drill core bit. At 8 weeks, defects were imaged using a mini-CT, laser scanning confocal microscopy and tissues collected for downstream assays including: focused osteo-induction gene and proteome arrays. Concurrently, in vitro studies utilizing baclovirus Premo Fucci® transduced MDSCs (fluorescent correlation to cell cycle stage) were monitored using a FV10i-LIV® live cell confocal imaging system. Quantitative data was extracted from confocal multi-sequence 3D-imaging of daily and real-time cell migration assays as well as cell cycle proliferation kinetic studies. Additionally cell-to-cell interaction and correlative osteo-differentiation characteristics were analyzed following scaffold substrate and hBMP-2 variation.

A Modified Approach to Component Separation Using Biologic Graft as a Load-Sharing Onlay Reinforcement for the Repair of Complex Ventral Hernia

Background. Components separation has been proposed as a means to close large ventral hernia without undue tension. We report a modification on open components separation that allows for the incorporation of onlaid noncrosslinked porcine acellular dermal matrix (Strattice, LifeCell Corp, Branchburg, NJ) as a load-sharing structure. Methods. This was a retrospective case series including all cases using Strattice from July 2008 through December 2009. Data evaluated included patient demographics, comorbidities associated with risk of recurrence, hernia grade, and postoperative complications. The primary outcomes were hernia recurrence and surgical site occurrences. Results. There were 58 patients; 60.8% presented with a recurrent incisional hernia. Average length of follow-up was 384 days. There were 4 hernia recurrences (7.9%). Complications included surgical site infection (20.7%), seroma (15.5%), and hematoma (5%) requiring intervention. Four deaths occurred in the series due to causes unrelated to the hernia repair, only 1 within 30 days of operation. Conclusions. This series demonstrates that components separation reinforced with noncrosslinked porcine acellular dermal matrix onlay is an efficacious, single-stage repair with a low rate of recurrence and surgical site occurrences.

Regeneration of Vascularized Corticocancellous Bone and Diploic Space Using Muscle-Derived Stem Cells: A Translational Biologic Alternative for Healing Critical Bone Defects

Background: Regeneration of functional bone substrate remains a priority in reconstructive surgery especially for patients suffering from complex skeletal defects. Efforts to develop implantable osteoinductive constructs and novel osteoconductive materials remain at the forefront of industry forces and product line development. Despite advancement in clinical practice and bone biology, cancellous autograft remains the gold standard for procedures requiring osteogenic mechanisms of healing. This study investigates the utility of muscle-derived stem cells as a cellular therapy for definitive bone regeneration through a form of neo-osteogenesis. Methods: Adipose-derived stem cell, bone marrow–derived mesenchymal stem cell, and muscle-derived stem cell populations were isolated separately from C57BL/6 murine tissues and supplemented with collagen scaffolding with or without bone morphogenetic protein-2 to compare relative osteogenic potency and ultrastructure organization in both two- and three-dimensional systems. Parallel populations were bound to a deployable collagen implant within a syngeneic murine cranial defect model. Results: Although all populations provided and maintained mesenchymal stem cell multilineage capacity, adipose-derived stem cell– and bone marrow–derived mesenchymal stem cell–enriched constructs were capable of forming small bone aggregates. Defects receiving muscle-derived stem cells self-assembled a form of organized corticocancellous structures within two- and three-dimensional in vitro systems and within the in vivo model. Muscle-derived stem cells also augmented healing, implant angiogenesis, and diploic space formation. Conclusion: Muscle-derived stem cell–enriched implants appear to provide an autologous response to current industry-derived products and an attractive alternative to mesenchymal stem cells for the regeneration of corticocancellous bone and a vascularized diploic space.

Versatility of Free Cutaneous Flaps for Upper Extremity Soft Tissue Reconstruction

The goals of upper extremity soft tissue reconstruction should go well beyond providing coverage and restoring function. As the field of reconstructive microsurgery has evolved, free cutaneous flaps (FCFs) are gaining wider application. The advantages of FCF include minimizing donor-site morbidity by preserving the muscle and fascia, improving versatility of flap design, and superior aesthetic results. This review highlights the application of anterolateral thigh, superficial circumflex iliac artery, deep inferior epigastric perforator, superficial inferior epigastric artery, and flow-through flaps for reconstruction of upper extremity defects. These flaps share several qualities in common: well-concealed donor sites, preservation of major arteries responsible of providing inflow to distal extremity, and potential for a two-team approach (donor and recipient sites). While the choice of flaps should be decided based on individual patient and defect characteristics, FCF should be considered as excellent options to achieve the goals of upper extremity reconstruction.

Which Factors Are Associated with Open Reduction of Adult Mandibular Condylar Injuries

Background: The purpose of this study was to identify factors associated with the decision to perform open reduction and internal fixation of mandibular condylar fractures. Methods: This was a retrospective cohort study of patients with mandibular condylar fractures managed by the plastic and reconstructive surgery, oral and maxillofacial surgery, and otorhinolaryngology services over a 15-year period. Bivariate associations and a multiple logistic regression model were computed for injury characteristics that were associated with open reduction and internal fixation. For all analyses, a value of p ⩽ 0.05 was considered significant. Results: Six hundred fifty-four condylar injuries were identified in 547 patients. The sample’s mean age was 36.0 ± 16.5 years, 20.5 percent were women, and 63 percent were Caucasian. The most common mechanisms of injury were motor vehicle collisions (49 percent), 53.4 percent involved the subcondylar region and 20 percent were bilateral injuries. Associated noncondylar mandibular fractures were present in 60 percent of cases; 20.7 percent were managed with open reduction and internal fixation. The overall complication rate was 21.6 percent. In a multiple logistic regression model, factors associated with an increased likelihood of open reduction and internal fixation were the presence of extracondylar mandibular injuries, condylar neck or subcondylar region injuries, increasing dislocation, and treatment by plastic and reconstructive surgery/oral and maxillofacial surgery (p ⩽ 0.04). Conclusions: Increasing severity of mandibular injury, lower level of fracture, joint dislocation, and treatment by plastic and reconstructive surgery/oral and maxillofacial surgery are associated with open reduction and internal fixation of mandibular condylar injuries. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Desensitization and prevention of antibody-mediated rejection in vascularized composite allotransplantation by syngeneic hematopoietic stem cell transplantation

Background Candidates for vascularized composite allotransplantation (VCA) are frequently sensitized, putting them at risk for antibody-mediated rejection. Current desensitization strategies are imperfect and require a living-donor setting. Here we investigated the impact of sensitization on and the efficacy of a desensitization protocol utilizing syngeneic hematopoietic stem cell transplantation (HSCT) to prevent antibody-mediated rejection in VCA. Methods Skin transplants from Dark Agouti to Lewis rats were performed for sensitization. Orthotopic hind limb transplants from Dark Agouti donors were performed to sensitized and nonsensitized recipients, and the animals were treated with either daily tacrolimus or no immunosuppression. A desensitization protocol consisting of total body irradiation, fludarabine, and syngeneic HSCT was applied to sensitized animals. Graft rejection was monitored by clinical assessment and histological analysis. Serum levels of donor-specific antibodies (DSA IgG) were measured using flow cytometry. Results Sensitized recipients exhibited accelerated rejection by 5.5 ± 1.2 days without immunosuppression and 10.2 ± 3.6 days with daily tacrolimus compared with 8.7 ± 1.2 days and longer than 30 days in nonsensitized recipients, respectively. Serum levels of DSA IgG were markedly elevated (37.3 ± 3.34-fold from baseline) in sensitized recipients after VCA and correlated with histologic evidence of rejection and C4d deposition. Desensitization significantly reduced DSA compared with sensitized controls (2.6 ± 0.5-fold vs 6.0 ± 1.2-fold, P < 0.01) and along with daily tacrolimus led to improved VCA survival longer than 30 days without evidence of C4d deposition (n = 6). Conclusions In summary, sensitization leads to accelerated rejection of VCA, and syngeneic HSCT combined with conventional immunosuppression effectively reduces DSA and improves allograft survival in sensitized rats.

Management of Bilateral Edentulous Mandible Fractures Through an Intraoral Approach Using CAD/CAM Technology: A Case Report

The surgical management of edentulous mandible fractures presents unique challenges secondary to poor bone stock and the absence of dentition to assist with fracture reduction. In complex injury patterns, such as bilateral edentulous mandible fractures, an external approach is often necessary to achieve adequate reduction and adaptation of a load-bearing reconstruction plate. We report a case in which computer-assisted design/computer-assisted manufacturing (CAD/CAM) was applied as an adjunct for the acute management of bilateral edentulous mandible fractures in a 58-year-old man. CAD/CAM technology was used to fabricate a patient-specific reconstruction plate and a maxillomandibular splint, which facilitated the successful treatment of this complex injury through an intraoral approach. This case highlights the potential of CAD/CAM technology to improve operative efficiency and clinical outcomes in the acute management of complex edentulous mandible fractures.