Soluble chitosan derivative treats wound infections and promotes wound healing in a novel MRSA-infected porcine partial-thickness burn wound model.

Burns are physically debilitating and potentially fatal injuries. The most common etiology of burn wound infections in the US is methicillin-resistant Staphylococcus aureus (MRSA), which is particularly recalcitrant when biofilms form. The current standard of care, silver sulfadiazine (SSD) is effective in reducing bacterial load, but less effective in improving burn wound healing. New treatments that can manage infection while simultaneously improving healing would provide a benefit in the treatment of burns. Porcine models are frequently used as a model for human wound healing but can be expensive due to the need to separate wounds to avoid cross contamination. The porcine model developed in this study offers the capability to study multiple partial thickness burn wound (PTBW) sites on a single animal with minimal crosstalk to study wound healing, infection, and inflammation. The current study evaluates a wound rinse and a wound gel formulated with a non-toxic, polycationic chitosan derivative that is hypothesized to manage infection while also promoting healing, providing a potential alternate to SSD. Studies in vitro and in this PTBW porcine model compare treatment with the chitosan derivative formulations to SSD. The wound rinse and wound gel are observed to disrupt mature MRSA biofilms in vitro and reduce the MRSA load in vivo when compared to that of the standard of care. In vivo data further show increased re-epithelialization and faster healing in burns treated with wound rinse/gel as compared to SSD. Taken together, the data demonstrate the potential of the wound rinse/gel to significantly enhance healing, promote re-epithelialization, and reduce bacterial burden in infected PTBW using an economical porcine model.

Management of Posttraumatic Avascular Necrosis of the Proximal Humerus.

The etiology of avascular necrosis (AVN) of the proximal humerus can be classified as idiopathic or posttraumatic, the latter being mainly due to proximal humerus fractures. Evidence suggests that posttraumatic AVN may require surgical intervention more often than idiopathic AVN of the proximal humerus. This article provides a comprehensive review of the management of posttraumatic AVN of the proximal humerus. Early stage AVN (stages 1 to 3) is commonly treated with nonoperative intervention or core decompression of the humeral head, whereas later stage disease (stages 4 and 5) may require hemiarthroplasty or total shoulder arthroplasty to restore function. [Orthopedics. 2021;44(6):367-375.].

Objective Analysis of Fronto-Orbital Dysmorphology in Unilateral Coronal Craniosynostosis.

ABSTRACT: Correction (and over-correction) of asymmetries of the orbital shape and brow position in unilateral coronal craniosynostosis (UCS) is critical to successful fronto-orbital advancement. Here we quantify and three-dimensionally assess fronto-orbital irregularities in UCS patients compared to controls.Twenty-three patients with UCS evaluated at the Children's Hospital of Pittsburgh between 2006 and 2016 were age and gender-matched to controls. Computed tomography scans were reconstructed and evaluated for orbital metrics. A three-dimensional heat map of orbital regions was generated and evaluated for shape differences.Brow protrusion of the orbit ipsilateral to the synostotic suture did not differ significantly from healthy controls. Orbital height was significantly increased while orbital width was decreased on the UCS ipsilateral side compared to the contralateral side and controls. The ipsilateral cornea was overprojected relative to the brow and the infraorbital rim, but similar to controls relative to the lateral rim. The contralateral orbit had increased brow protrusion with decreased orbital height. The cornea was underprojected relative to the brow, but overprojected relative to the lateral orbital rim and similar to controls at the infraorbital rim. Three-dimensional comparison demonstrated significant overprojection of the contralateral brow, with some more mild and inconsistent underprojection of the lateral aspect of the ipsilateral brow.Key orbital and brow differences exist between the affected and unaffected sides in UCS. This study provides quantitative data that further characterize the orbital dysmorphology observed in UCS and identifies unique aspects of the diagnosis that should be taken into consideration during surgical planning.

Quantifying the Severity of Metopic Craniosynostosis: A Pilot Study Application of Machine Learning in Craniofacial Surgery.

The standard for diagnosing metopic craniosynostosis (CS) utilizes computed tomography (CT) imaging and physical exam, but there is no standardized method for determining disease severity. Previous studies using interfrontal angles have evaluated differences in specific skull landmarks; however, these measurements are difficult to readily ascertain in clinical practice and fail to assess the complete skull contour. This pilot project employs machine learning algorithms to combine statistical shape information with expert ratings to generate a novel objective method of measuring the severity of metopic CS.Expert ratings of normal and metopic skull CT images were collected. Skull-shape analysis was conducted using ShapeWorks software. Machine-learning was used to combine the expert ratings with our shape analysis model to predict the severity of metopic CS using CT images. Our model was then compared to the gold standard using interfrontal angles.Seventeen metopic skull CT images of patients 5 to 15 months old were assigned a severity by 18 craniofacial surgeons, and 65 nonaffected controls were included with a 0 severity. Our model accurately correlated the level of skull deformity with severity (P < 0.10) and predicted the severity of metopic CS more often than models using interfrontal angles (χ = 5.46, P = 0.019).This is the first study that combines shape information with expert ratings to generate an objective measure of severity for metopic CS. This method may help clinicians easily quantify the severity and perform robust longitudinal assessments of the condition.

An Intraoperative Salvage After Transection of the Greater Palatine Artery During Cleft Palate Repair: A Case for Buccal Fat and Buccal Myomucosal Flaps.

Recently, several adjunctive procedures have gained traction to aid cleft surgeons in repairing especially challenging palatal clefts. Buccal fat flaps and buccal myomucosal flaps have demonstrated particular utility in reinforcing thin palatal flaps or tissue deficits. Although their use has not been widely accepted, they may be particularly helpful in the setting of significant scarring or vascular compromise. Here the authors describe the case of an intraoperative salvage using bilateral buccal fat flaps and a right buccal myomucosal flap after transection of the right Greater Palatine artery (GPA) during palatoplasty on a 14-month old female with Pierre Robin Sequence and a wide Veau II cleft palate. For this operative salvage, bilateral buccal fat flaps were used to reinforce the hard-soft palate junction and a 4 cm × 2 cm flap of the right-sided buccal mucosa and buccinator muscle was inset along the majority of the right-sided soft and posterior hard palate. At 2 years follow-up, the patient had no significant complications and was doing well with healthy-appearing palatal tissue and age-appropriate speech.

Demineralized Bone Matrix and Resorbable Mesh Bilaminate Cranioplasty Is Ineffective for Secondary Reconstruction of Large Pediatric Cranial Defects.

Replacement of the autologous bone flap after decompressive craniectomy can be complicated by significant osteolysis or infection with large defects over scarred dura. Demineralized bone matrix is an alternative to autologous reconstruction, effective when reconstructing large defects using a resorbable mesh bilaminate technique in primary cranioplasty, but this technique has not been studied for revision cranioplasty and the setting of scarred dura. Retrospective review was performed of patients receiving demineralized bone matrix and resorbable mesh bilaminate cranioplasty for postdecompressive craniectomy defects. Seven patients (mean age, 4.2 years) were identified with a mean follow-up of 4.0 years. Computed tomography before the demineralized bone matrix and resorbable mesh bilaminate cranioplasty and at least 1 year postoperatively were compared. Defects were characterized and need for revision was assessed. All patients had craniectomy with associated hemidural scarring. Five patients had autologous bone flap cranioplasty associated with nearly total osteolysis, and two patients had deferral of bone flap before demineralized bone matrix and resorbable mesh bilaminate cranioplasty. Demineralized bone matrix and resorbable mesh bilaminate cranioplasty demonstrated unpredictable and poor ossification, with bony coverage unchanged at postoperative follow-up. All patients required major revision cranioplasty at a mean time of 2.5 years. Porous polyethylene was successfully used in six of the revisions, whereas exchange cranioplasty was used in the remaining patient, with a mean follow-up of 1.4 years. Although demineralized bone matrix and resorbable mesh bilaminate is appropriate for primary cranioplasty, it should be avoided in the setting of scarred or infected dura in favor of synthetic materials or exchange cranioplasty. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, IV.

The Effect of DUCOM's Mini-Medical School Summer Camp on Students' Interests in Medicine.

Drexel University College of Medicine hosts two, three-week long Mini-Medical School Summer Camps each summer. These programs offer high-school seniors and freshmen in college the opportunity to experience various aspects of medical school and the life of a physician: attending lectures, observing surgeries, shadowing clinical physicians, etc. The purpose of this study is to see if the program increases students' interest in pursuing a career in medicine, the aspects of the program that accomplish this, and assess general satisfaction of the program. Information was collected from surveys administered to students before and after completion of the program. The program failed to show a difference in students' interest of pursuing a career in medicine before and after the program. Experiences in the operating room and ambulatory care (shadowing) were shown to be most influential on a student's decision to pursue a career in medicine. Students indicated the most enjoyed activity for both sessions was observing surgeries in the operating room. The majority of students would do the program again and recommend the program to their friends. Future studies should be conducted on similar programs to look at variables such as different age groups or socioeconomic statuses, and the impact these factors have on pursuing careers in medicine.