Supervening Abscess Resulting in Streptococcus pyogenes Toxic Shock Syndrome Complicated by a Recent MRSA Infection in an Active Duty Military Member.

An 18-year-old male active duty US Army service member presented to the emergency department with a lower leg abscess in the region of a previously debrided methicillin-resistant Staphylococcus aureus abscess. After initial presentation, the patient became hypotensive, exhibited signs of renal failure, and developed a diffuse erythematous rash. Streptococcus pyogenes was grown from intraoperative cultures, and he was diagnosed with Streptococcal toxic shock syndrome (STSS). The patient subsequently underwent multiple surgical debridements, intravenous immunoglobulin treatment, and intravenous antibiotic administration. Streptococcal toxic shock syndrome may have a rapid onset and cause a sharp decline in hemodynamic status requiring admission to the intensive care unit. Any source of virulent Streptococcal pyogenes infection can cause STSS, including lower extremity abscesses. Therefore, it is imperative for physicians to recognize systemic involvement of seemingly isolated extremity infections. We encourage a high index of suspicion in treating bacterial abscesses for possible complications, and close monitoring of patient status. This suspicion should be even higher during outbreaks of bacteria that can cause STSS, much like the patient presented here.

The last days: The medical response of United States and allied military teams during the Afghanistan Exodus.

OBJECTIVES: The objective of this study is to describe the United States and allied military medical response during the withdrawal from Afghanistan. BACKGROUND: The military withdrawal from Afghanistan concluded with severe hostilities resulting in numerous civilian and military casualties. The clinical care provided by coalition forces capitalized on decades of lessons learned and enabled unprecedented accomplishments. METHODS: In this retrospective, observational analysis, casualty numbers, and operative information was collected and reported from military medical assets in Kabul, Afghanistan. The continuum of medical care and the trauma system, from the point of injury back to the United States was captured and described. RESULTS: Prior to a large suicide bombing resulting in a mass casualty event, the international medical teams managed distinct 45 trauma incidents involving nearly 200 combat and non-combat civilian and military patients over the preceding 3 months. Military medical personnel treated 63 casualties from the Kabul airport suicide attack and performed 15 trauma operations. US air transport teams evacuated 37 patients within 15 hours of the attack. CONCLUSION: Lessons learned from the last 20 years of combat casualty care were successfully implemented during the culmination of the Afghanistan conflict. Ultimately, the effort, teamwork, and system adaptability exemplify not only the attitudes and character of service members who provide modern combat casualty care but also the paramount importance of the battlefield learning health care system. A continued posture to maintain military surgical preparedness in unique environments remain crucial as the US military prepares for the future.Retrospective observational analysis. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level V.

Dunning-Kruger Effect Between Self-Peer Ratings of Surgical Performance During a MASCAL Event and Pre-Event Assessed Trauma Procedural Capabilities.

Objectives: The research question asked to what extent do self-rated performance scores of individual surgeons correspond to assessed procedural performance abilities and to peer ratings of procedural performance during a mass casualty (MASCAL) event? Background: Self-assessment using performance rating scales is ubiquitous in surgical education as a proxy for direct measurement of competence. The validity and reliability of self-ratings as competency measures are susceptible to cognitive biases such as Dunning-Kruger effects, which describe how individuals over/underestimate their own performance compared to assessments from independent sources. The ability of surgeons to accurately self-assess their procedural performance remains undetermined. Methods: A purposive sample of military surgeons (N = 13) who collectively cared for trauma patients during a MASCAL event participated in the study. Pre-event performance assessment scores for 32 trauma procedures were compared with post-event self and peer performance ratings using F tests (P < 0.05) and effect sizes (Cohen's d). Results: There were no significant differences between peer ratings and performance assessment scores. There were significant differences between self-ratings and both peer ratings (P < 0.001) and performance assessment scores (P < 0.001). Effect sizes were very large for self to peer rating comparison (Cohen's d = 2.34) and self to performance assessment comparison (Cohen's d = 2.77). Conclusions: The outcomes demonstrate that self-ratings were significantly lower than the independently determined assessment scores for each surgeon, revealing a Dunning-Kruger effect for highly skilled individuals underestimating their abilities. These outcomes underscore the limitations of self-assessment for measuring competence.

Augmented Reality Forward Damage Control Procedures for Nonsurgeons: A Feasibility Demonstration.

INTRODUCTION: This article presents an emerging capability to project damage control procedures far forward for situations where evacuation to a formal surgical team is delayed. Specifically, we demonstrate the plausibility of using a wearable augmented reality (AR) telestration device to guide a nonsurgeon through a damage control procedure. METHODS: A stand-alone, low-profile, commercial-off-the-shelf wearable AR display was utilized by a remotely located surgeon to synchronously guide a nonsurgeon through proximal control of the distal external iliac artery on a surgical manikin. The manikin wound pattern was selected to simulate a rapidly exsanguinating junctional hemorrhage not controllable by nonsurgical means. RESULTS: This capability demonstration displayed successful use of AR technology, telecommunication, and procedural training and guidance in a single test pilot. The assisted physician assistant was able to rapidly control the simulated external iliac artery injury on this model. The telestration system used was commercially available for use with available civilian cell phone, wireless and satellite networks, without the need for dedicated high-speed networks. CONCLUSIONS: A nonsurgeon, using a wearable commercial on-visual-axis telestration system, successfully performed a damage control procedure, demonstrating the plausibility of this approach.

Sliding Hip Screw for Fixation of Fracture Through a Previously Arthrodesed Hip.

Hip arthrodesis is a treatment option for painful chronic hip conditions. Hip fractures through a previously arthrodesed hip are relatively uncommon as indications for hip arthrodesis are rare. The following case reports on the use of a sliding hip screw and a pelvic reconstruction plate to address arthrodesed hip fracture in an 81-year-old man. The use of a dynamic hip screw in this setting gave us a stable fixed-angle construct with compression across the fracture site, and the addition of a trochanteric side plate added to the stability. The dynamic compression plate with limited bone contact was used to neutralize the construct. This case describes the successful treatment of such an injury in a way not previously described in the literature with the intent of giving the orthopaedic traumatologist another method to approach this rare injury.

Patella Fracture in US Servicemember in an Austere Location.

OBJECTIVE: Review the management of a patient with acute patella fracture supported by telemedical consultation. Clinical Context: Regionally Aligned Forces (RAF) supporting US Army Africa/Southern European Task Force (USARAF/ SETAF) in Africa Command area of responsibility. Care was provided by a Role I facility on the compound. Organic Expertise: Three 68W combat medics; one Special Operations Combat Medic (SOCM). Closest Medical Support: Organic battalion physician assistant (PA) located in the United States; USARAF PA located in a European country; French Role II located in nearby West African country; telemedical consults via e-mail, phone, or videoteleconsultation. Earliest Evacuation: Estimated at 12 to 24 hours with appropriate clearances.

Health trends in the wake of the financial crisis-increasing inequalities?

AIM: The financial crisis that hit Europe in 2007-2008 and the corresponding austerity policies have generated concern about increasing health inequalities, although impacts have been less salient than initially expected. One explanation could be that health inequalities emerged first a few years into the crisis. This study investigates health trends in the wake of the financial crisis and analyses health inequalities across a number of relevant population subgroups, including those defined by employment status, age, family type, gender, and educational attainment. METHODS: This study uses individual-level panel data (EU-SILC, 2010-2013) to investigate trends in self-rated health. By applying individual fixed effects regression models, the study estimates the average yearly change in self-rated health for persons aged 15-64 years in 28 European countries. Health inequalities are investigated using stratified analyses. RESULTS: Unemployed respondents, particularly those who were unemployed in all years of observation, had a steeper decline in self-rated health than the employed. Respondents of prime working age (25-54 years) had a steeper decline than their younger (15-24) and older (55-64) counterparts, while single parents had a more favorable trend in self-rated health than dual parents. We did not observe any increasing health inequalities based on gender or educational attainment. CONCLUSIONS: Health inequalities increased in the wake of the financial crisis, especially those associated with employment status, age, and family type. We did not observe increasing health inequalities in terms of levels of educational attainment and gender.

Epidural Neostigmine versus Fentanyl to Decrease Bupivacaine Use in Patient-controlled Epidural Analgesia during Labor: A Randomized, Double-blind, Controlled Study.

BACKGROUND: The addition of opioids to epidural local anesthetic reduces local anesthetic consumption by 20% but at the expense of side effects and time spent for regulatory compliance paperwork. Epidural neostigmine also reduces local anesthetic use. The authors hypothesized that epidural bupivacaine with neostigmine would decrease total hourly bupivacaine use compared with epidural bupivacaine with fentanyl for patient-controlled epidural analgesia. METHODS: A total of 215 American Society of Anesthesiologists physical status II, laboring parturients requesting labor epidural analgesia consented to the study and were randomized to receive 0.125% bupivacaine with the addition of either fentanyl (2 µg/ml) or neostigmine (2, 4, or 8 µg/ml). The primary outcome was total hourly local anesthetic consumption, defined as total patient-controlled epidural analgesia use and top-ups (expressed as milliliters of 0.125% bupivacaine) divided by the infusion duration. A priori analysis determined a group size of 35 was needed to have 80% power at α = 0.05 to detect a 20% difference in the primary outcome. RESULTS: Of 215 subjects consented, 151 patients were evaluable. Demographics, maternal and fetal outcomes, and labor characteristics were similar among groups. Total hourly local anesthetic consumption did not differ among groups (P = 0.55). The total median hourly bupivacaine consumption in the fentanyl group was 16.0 ml/h compared with 15.3, 14.6, and 16.2 ml/h in the 2, 4, and 8 µg/ml neostigmine groups, respectively (P = 0.55). CONCLUSIONS: The data do not support any difference in bupivacaine requirements for labor patient-controlled epidural analgesia whether patients receive epidural bupivacaine with 2 to 8 µg/ml neostigmine or epidural bupivacaine with 2 µg/ml fentanyl.

Infection of rhesus macaques with a pool of simian immunodeficiency virus with the envelope genes from acute HIV-1 infections.

BACKGROUND: New simian-human immunodeficiency chimeric viruses with an HIV-1 env (SHIVenv) are critical for studies on HIV pathogenesis, vaccine development, and microbicide testing. Macaques are typically exposed to single CCR5-using SHIVenv which in most instances does not reflect the conditions during acute/early HIV infection (AHI) in humans. Instead of individual and serial testing new SHIV constructs, a pool of SHIVenv_B derived from 16 acute HIV-1 infections were constructed using a novel yeast-based SHIV cloning approach and then used to infect macaques. RESULTS: Even though none of the 16 SHIVenvs contained the recently reported mutations in env genes that could significantly enhance their binding affinity to RhCD4, one SHIVenv (i.e. SHIVenv_B3-PRB926) established infection in macaques exposed to this pool. AHI SHIVenv_B viruses as well as their HIVenv_B counterparts were analyzed for viral protein content, function, and fitness to identify possible difference between SHIVenv_B3-PRB926 and the other 15 SHIVenvs in the pool. All of the constructs produced SHIV or HIV chimeric with wild type levels of capsid (p27 and p24) content, reverse transcriptase (RT) activity, and expressed envelope glycoproteins that could bind to cell receptors CD4/CCR5 and mediate virus entry. HIV-1env_B chimeric viruses were propagated in susceptible cell lines but the 16 SHIVenv_B variants showed only limited replication in macaque peripheral blood mononuclear cells (PBMCs) and 174×CEM.CCR5 cell line. AHI chimeric viruses including HIVenv_B3 showed only minor variations in cell entry efficiency and kinetics as well as replicative fitness in human PBMCs. Reduced number of N-link glycosylation sites and slightly greater CCR5 affinity/avidity was the only distinguishing feature of env_B3 versus other AHI env's in the pool, a feature also observed in the HIV establishing new infections in humans. CONCLUSION: Despite the inability to propagate in primary cells and cell lines, a pool of 16 SHIVenv viruses could establish infection but only one virus, SHIVenv_B3 was isolated in the macaque and then shown to repeatedly infected macaques. This SHIVenv_B3 virus did not show any distinct phenotypic property from the other 15 SHIVenv viruses but did have the fewest N-linked glycosylation sites.

Infection After Orthopaedic Trauma: Prevention and Treatment.

Trauma to the extremities is disproportionately represented in casualties of recent conflicts, accounting for >50% of injuries sustained during operations in Iraq and Afghanistan. Infectious complications have been reported in >25% of those evacuated for trauma, and 50% of such patients were treated in the intensive care unit (ICU). Osteomyelitis has been reported in 9% (14% of intensive care unit patients), and deep-wound infection in 27% of type III open-tibia fractures. Infections complicating extremity trauma are frequently caused by multidrug-resistant bacteria and have been demonstrated to lead to failure of limb salvage, unplanned operative take-backs, late amputations, and decreased likelihood of returning to duty. Invasive fungal infections of extremities have also presented a unique challenge in combat-injured patients, particularly in those with blast injuries with massive transfusion requirements and high injury severity scores. Infection prevention should begin at the time of injury and, although context-specific depending on the level of care, includes appropriate irrigation, surgical debridement, wound care and coverage, fracture fixation, and antibiotic prophylaxis, in addition to basic infection prevention measures. Clinical practice guidelines to address infection prevention after combat trauma (including extremity infection) were developed in 2007 and revised in 2011, with endorsement from the Surgical Infection Society and the Infectious Disease Society of America. Nevertheless, significant challenges remain, including austere environments of care, multiple transitions of care, and lack of coordinated efforts in prevention. Treatment of established infections is optimally multidisciplinary, particularly when deep wounds, bone, and joints are involved. Surgical debridement of overtly infected or necrotic tissue is necessary, with particularly aggressive margins if invasive fungal infection is suspected. Infected nonunion frequently requires the use of prosthetic materials for fixation, potentiating biofilm formation, and complicating medical therapy. Antibiotic therapy should be targeted at results of deep wound and bone cultures. However, this is complicated by frequent contamination of wounds, requiring differentiation between potential pathogens in terms of their virulence and decreased culture recovery in patient who have frequently received previous antibiotics. Lessons learned in infection prevention and treatment of orthopaedic trauma from combat can serve to inform the care of patients injured in natural disasters and noncombat trauma.

Decomposing the effect of social policies on population health and inequalities: an empirical example of unemployment benefits.

AIM: The purpose of this study is to discuss and empirically contrast different conceptualizations and operationalizations of social policies in analysing health and educational differences in health cross-nationally. METHODS: Country-level institutional and expenditure data on unemployment benefit schemes and individual-level data from the EU-SILC for 23 countries were used to analyse the association between unemployment benefits and self-assessed health for individuals with different educational attainment. RESULTS: The analyses indicate that higher coverage rate (i.e. the proportion of the relevant population eligible for benefits) is associated with better self-related health among both low- and high-educated individuals, but is not linked to smaller educational differences in health. In contrast, replacement rate (i.e. the amount of benefits received) in isolation is not related to self-assessed health. However, in countries where coverage rates are high, higher replacement rates are associated with better health among both low- and high-educated individuals and smaller educational differences in health. CONCLUSIONS: Decomposing unemployment benefit programmes into two main dimensions--the proportion in the labour force covered by such programmes and the replacement rate received in case of unemployment--may present further insights into institutional mechanisms linking macro-level social policies to individual-level health outcomes.

Salsalate, an old, inexpensive drug with potential new indications: a review of the evidence from 3 recent studies.

BACKGROUND: Diabetes is a well-known growing epidemic, but prediabetes is increasing at an even greater rate. Lifestyle changes are effective tools to prevent the progression of prediabetes to diabetes, yet many people are unable to follow such changes. Salsalate has been suggested as a possible treatment for diabetes as early as 1876 and as recently as in a 2013 study. OBJECTIVE: To review the recently published evidence about the potential therapeutic benefits of the old drug salsalate for individuals who meet the criteria of having prediabetes. DISCUSSION: With the rising incidence of obesity and prediabetes, it has become prudent to look for more therapeutic options. Salsalate belongs to the salicylate drug class, which has been shown to inhibit I-κB kinase, thereby inhibiting the nuclear factor-κB (NF-κB) cascade and decreasing the production of inflammatory cytokines, as well as decreasing insulin resistance. Recent short-term clinical trials have shown that 3 g to 4.5 g of salicylate therapy daily has the ability to lower insulin resistance and to reduce the levels of glucose, triglycerides, and free fatty acid concentrations through regulation of the I-κB kinase beta/NF-κB pathway, with few if any side effects. However, the effectiveness of salsalate as a treatment option for prediabetes is largely unrecognized. This article summarizes the current evidence from 3 studies of salsalate therapy in the setting of the prediabetic population and presents the case for its use in this population. CONCLUSION: As shown in this review, salsalate therapy at the dose of 3 g to 4.5 g daily can lower insulin resistance and reduce the levels of glucose, triglycerides, and free fatty acid concentrations with minimal side effects. This inexpensive medication could be a useful option in the treatment of prediabetes. Larger clinical trials are needed, but the data are encouraging and should lay the foundation for further investigation and grant funding.

Association between cervical and thoracic somatic dysfunction among second-year osteopathic medical students.

CONTEXT: The ubiquitous nature of cervical and thoracic somatic dysfunction requires osteopathic physicians to have a strong working knowledge of regional spinal mechanics and their functional and dysfunctional interrelationships. OBJECTIVE: To determine whether cervical and thoracic somatic dysfunction occur concomitantly, particularly somatic dysfunction of the occipitoatlantal (OA) and upper thoracic (T1-T4) region of the spine. METHODS: A retrospective analysis of cervical and thoracic somatic dysfunction prevalence diagnosed by faculty in second-year osteopathic medical students was conducted. Somatic dysfunction was defined as a vertebral unit possessing any of the following palpatory characteristics: tissue texture changes, asymmetry of motion and relative position, restriction of motion, or tenderness (ie, TART criteria). For each instance of somatic dysfunction diagnosed, the segmental level identifying the superior segment of the involved vertebral unit was recorded, as well as the spinal region (ie, cervical [OA, atlantoaxial (AA), and C2-C7] or thoracic [T1-T12]). Descriptive analyses, a Pearson χ(2) test, and a regression model using an analysis of variance were performed on the data. RESULTS: Among 338 students included in the study, the following 5 vertebral segments were found to have the highest prevalence of somatic dysfunction: OA (257 [76.0%]), C3 (257 [76.0%]), T3 (247 [73.1%]), T5 (226 [66.9%]), and T4 (223 [66.0%]). A Pearson χ(2) test of association between the OA vertebral segment and the following segments were found to be statistically significant: AA (P=.024), C2 (P=.032), and T4 (P=.045). An analysis of variance revealed statistical significance between the prevalence of upper cervical (OA, AA, C2) somatic dysfunction and the prevalence of upper thoracic (P<.001) and midthoracic (T5-T8) (P<.001) somatic dysfunction; the prevalence of lower cervical (C3-C7) (P=.74) and lower thoracic (T9-T12) (P=.085) somatic dysfunction was not found to be significant. CONCLUSION: A statistically significant association between cervical somatic dysfunction and thoracic somatic dysfunction was confirmed. In addition, there was a statistically significant association between dysfunction of the OA and the AA, C2, and T4 vertebral segments. These results suggest that the number of dysfunctional vertebral segments in the upper thoracic and midthoracic spinal regions is directly proportional to the number of dysfunctional segments found in the upper cervical spinal region.

Welfare states and population health: the role of minimum income benefits for mortality.

The causes of cross-national differences in population health are subject for intense discussion, often focusing on the role of structural economic factors. Although population health is widely believed to reflect the living conditions in society, surprisingly few comparative studies systematically assess policy impacts of anti-poverty programs. In this paper we estimate the influence of minimum income benefits on mortality using international data on benefit levels in 18 countries 1990-2009. Included are all major non-contributory benefits that low-income households may receive. Our analyses, based on fixed effects pooled time-series regression, show that minimum income benefits improve mortality, measured in terms of age-standardized death rates and life expectancy. The results on country-level links between minimum income benefits and mortality are remarkably robust in terms of measured confounding effects.

Unemployment insurance and deteriorating self-rated health in 23 European countries.

BACKGROUND: The global financial crisis of 2008 is likely to have repercussions on public health in Europe, not least through escalating mass unemployment, fiscal austerity measures and inadequate social protection systems. The purpose of this study is to analyse the role of unemployment insurance for deteriorating self-rated health in the working age population at the onset of the fiscal crisis in Europe. METHODS: Multilevel logistic conditional change models linking institutional-level data on coverage and income replacement in unemployment insurance to individual-level panel data on self-rated health in 23 European countries at two repeated occasions, 2006 and 2009. RESULTS: Unemployment insurance significantly reduces transitions into self-rated ill-health and, particularly, programme coverage is important in this respect. Unemployment insurance is also of relevance for the socioeconomic gradients of health at individual level, where programme coverage significantly reduces health risks attached to educational attainment. CONCLUSIONS: Unemployment insurance mitigated adverse health effects both at individual and country-level during the financial crisis. Due to the centrality of programme coverage, reforms to unemployment insurance should focus on extending the number of insured people in the labour force.

Risk factors for complications and in-hospital mortality following hip fractures: a study using the National Trauma Data Bank.

STUDY DESIGN: Retrospective review of prospectively collected data. OBJECTIVE: To describe the impact of patient demographics, injury-specific factors, and medical co-morbidities on outcomes after hip fracture using the National Sample Program (NSP) of the National Trauma Data Bank (NTDB). METHODS: The 2008 NSP-NTDB was queried to identify patients sustaining hip fractures. Patient demographics, co-morbidities, injury-specific factors, and outcomes (including mortality and complications) were recorded and a national estimate model was developed. Unadjusted differences for risk factors were evaluated using t test/Wald Chi square analyses. Weighted logistic regression and sensitivity analyses were performed to control for all factors in the model. RESULTS: The weighted sample contained 44,419 incidents of hip fracture. The average age was 72.7. Sixty-two percent of the population was female and 80 % was white. The mortality rate was 4.5 % and 12.5 % sustained at least one complication. Seventeen percent of patients who sustained at least one complication died. Dialysis, presenting in shock, cardiac disease, male sex, and ISS were significant predictors of mortality, while dialysis, obesity, cardiac disease, diabetes, and a procedure delay of ≥2 days influenced complications. The major potential modifiable risk factor appears to be time to procedure, which had a significant impact on complications. CONCLUSIONS: This is the first study to postulate predictors of morbidity and mortality following hip fracture in a US national model. While many co-morbidities appear to be influential in predicting outcome, some of the more significant factors include the presence of shock, dialysis, obesity, and time to surgery. LEVEL OF EVIDENCE: Prognostic study, Level II.

Pelvic trauma: What are the predictors of mortality and cardiac, venous thrombo-embolic and infectious complications following injury?

INTRODUCTION: This study sought to determine risk factors that influence mortality, cardiac events, venous thrombo-embolic disease (VTED), and infection following fractures of the pelvis and/or acetabulum. METHODS: The 2008 National Sample Program (NSP) of the National Trauma Databank was queried to identify all patients who sustained pelvic and acetabular fractures. Demographic data, injury-specific and surgical characteristics, and medical co-morbidities were abstracted. The occurrence of in-hospital mortality, cardiac events, VTED and infections were documented. Univariate testing, weighted logistic regression, and sensitivity analyses were performed to identify significant independent predictors of mortality and the complications under study. RESULTS: The NSP contained 41,297 cases of pelvic trauma. In-hospital mortality was documented in 3055 (7%) and one or more complications occurred in 6932 (17%). Cardiac events transpired in 2% of patients, VTED in 4% and infections in 3%. Increasing age, shock, time to procedure, ISS, and GCS were predictive of mortality. Cardiac events were found to be influenced by obesity, diabetes, ISS, GCS, age, and trauma mechanism. VTED was impacted by obesity, history of respiratory disease, male sex, ISS, GCS, medical co-morbidities, and time to procedure. Injuries caused by mechanisms other than blunt trauma, shock, age, ISS, GCS, medical co-morbidities, and time to procedure were associated with infection. CONCLUSIONS: Several important predictors were identified for specific complications and mortality following pelvic trauma. The design of this study may render it more generalisable to American patients with pelvic injuries. LEVEL OF EVIDENCE: II - Prognostic retrospective study of a prospective dataset.

Genomewide molecular and biologic characterization of biomembrane formation adjacent to a methacrylate spacer in the rat femoral segmental defect model.

OBJECTIVES: This study focuses upon the morphologic and molecular features of the layer of cells, termed the "biomembrane," which forms around methacrylate spacers in bone segmental defects. The objective of this research was to assess the biomembrane formed in a novel rodent femoral segmental defect model at 4, 8, and 16 weeks with histologic and molecular studies. METHODS: Following Institutional Animal Care and Use Committee approval, a segmental defect was created in the rat femur and stabilized with the AO LockingRatNail and analyzed at 4, 8, and 16 weeks postsurgery using digital radiologic imaging, morphological and immunohistochemical studies, and genomewide gene expression studies employing microarray analysis. RESULTS: The biomembrane formed around the methacrylate spacer was rich in vasculature, which showed vascular endothelial growth factor immunolocalization. The biomembrane supported development of foci of bone and cartilage within it. Bone morphogenetic protein 2 immunolocalization and gene expression were positive within developing osseous and chondrocyte foci. Microarray analysis showed significant expression of key genes related to bone and cartilage formation and angiogenesis. CONCLUSIONS: This rat bone model was effective in creation of the biomembrane. Bone and cartilage foci were formed within the vascularized biomembrane with associated expression of genes critical for bone and cartilage development/formation and vascularization. The polymethyl methacrylate-induced biomembrane offers an exciting potential solution for segmental defects; the biomembrane, may act as a receptive bed and also serve as a source for mesenchymal stem cells, which could be recruited/directed for the healing process.

The nature and incidence of musculoskeletal combat wounds in Iraq and Afghanistan (2005-2009).

OBJECTIVES: This investigation sought to describe orthopaedic wounds sustained by service members deployed to Iraq or Afghanistan from 2005 to 2009. DESIGN: Retrospective review of prospective data. SETTING: : Joint Theater Trauma Registry (JTTR). PATIENTS: The 6092 musculoskeletal casualties contained in the JTTR. INTERVENTION: The JTTR was queried to identify all personnel sustaining musculoskeletal injuries in the period 2005-2009. Demographic information, injury mechanism, and nature of wounds were determined for all individuals. Deployment data for all service members were obtained through the Defense Manpower Data Center and the incidence of orthopaedic injuries and wounding patterns was assessed. MAIN OUTCOME MEASUREMENTS: Pairwise comparisons were made to identify statistically significant differences in incidence, and significant associations, between injury mechanism and injuries/wounding patterns. RESULTS: The JTTR contained data on 6092 musculoskeletal casualties with 17,177 wounds. Seventy-seven percent of all casualties sustained a musculoskeletal wound. The incidence of musculoskeletal combat casualties was 3.06 per 1000 deployed personnel per year, with fractures occurring in 3.41 per 1000 and soft-tissue wounds most commonly encountered (4.04 per 1000). Amputations represented 6% of all combat wounds. Most musculoskeletal wounds were caused by explosive blast (P < 0.001), as were nearly all traumatic amputations. CONCLUSIONS: This study represents the most complete description of the scope of orthopaedic war trauma. It also presents injury-specific incidences that have not previously been described for musculoskeletal combat casualties. Musculoskeletal casualties may occur in 3 of every 1000 personnel deployed per year. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.