Infection reduces return-to-duty rates for soldiers with Type III open tibia fractures

Deep Surgical Site Infection after Fracture Has a Profound Effect on Functional Outcomes

Background

Fracture-related infection is one of the most challenging complications in orthopaedic trauma surgery. However, the effect of infection on functional and pain-related outcomes has not been well established. The aims of this study were to evaluate functional recovery for patients with fracture and a deep surgical site infection compared with patients with fracture without infection and to evaluate whether pain severity, social support, and preinjury mental health have a moderating effect on the magnitude and direction of the relationship between deep surgical site infection and functional recovery.

Methods

This is a secondary retrospective cohort study using prospectively collected data from the VANCO trial (Local Antibiotic Therapy to Reduce Infection After Operative Treatment of Fractures at High Risk of Infection) and the OXYGEN (Supplemental Perioperative Oxygen to Reduce Surgical Site Infection After High Energy Fracture Surgery) trial. In this study, 2,116 patients with tibial plateau, pilon, or calcaneal fractures at high risk for infection were included. Patients were divided into cohorts of patients who experienced a deep surgical site infection and those who did not. The primary outcome measure was the functional outcome using the Veterans RAND 12-Item Health Survey (VR-12).

Results

After controlling for covariates, deep surgical site infection was independently associated with functional outcome, with a 3.3-point reduction in the VR-12 Physical Component Score, and pain severity was independently associated with functional outcome, with a 2.5-point reduction in the VR-12 Physical Component Score. Furthermore, the Brief Pain Inventory pain severity demonstrated an important moderating effect on the relationship between infection and functional outcome. In patients with lower pain scores, infection had a large negative impact on functional outcome, whereas, in patients with higher pain scores, infection had no significant impact on functional outcome. Furthermore, the functional outcome in the entire cohort remains at only 61% of baseline.

Conclusions

This study documents the negative impact of postoperative infection on functional recovery after injury, as well as the novel finding of pain severity as an important moderating factor. This study emphasizes not only the importance of developing effective interventions designed to reduce postoperative infection, but also the role that factors that moderate pain severity plays in limiting recovery of physical function.

Level of evidence

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Quantitative and Qualitative Literature Analysis of the Orthopedic Surgeons' Experience: Reflecting on 20 Years in the Global War on Terror

INTRODUCTION

After over 20 years of war in the Middle East, orthopedic injuries have been among the most prevalent combat-related injuries, accounting for 14% of all surgical procedures at Role 2/3 (R2/R3) facilities according to the DoD Trauma Registry. To further delineate the role of the deployed orthopedic surgeon on the modern battlefield, a retrospective review was performed highlighting both quantitative and qualitative analysis factors associated with orthopedic surgical care during the war in the Middle East.

METHODS

A retrospective review was conducted of orthopedic surgeons in the Middle East from 2001 to 2021. A comprehensive literature search was conducted using the PubMed and Embase databases using a two-reviewer strategy. Articles were compiled and reviewed using Covidence. Inclusion criteria included journal articles focusing on orthopedic injuries sustained during the Global War on Terror (GWoT) in an adult U.S. Military population. In the event of a conflict, a third author would determine the relevance of the article. For the remaining articles, a full-text review was conducted to extract relevant predetermined quantitative data, and the Delphi consensus method was then utilized to highlight relevant qualitative themes.

RESULTS

The initial search yielded 1,226 potentially relevant articles. In all, 40 studies ultimately met the eligibility criteria. With the consultation of previously deployed orthopedic surgeons at the Walter Reed National Military Medical Center, a retrospective thematic analysis of the 40 studies revealed five themes encompassing the orthopedic surgeons experience throughout GWoT. These themes include unique mechanisms of orthopedic injury compared to previous war injuries due to novel weaponry, differences in interventions depending on R2 versus R3 locations, differences in injuries from those seen in civilian settings, the maintained emphasis on humanitarian aspect of an orthopedic surgeon's mission, and lastly relation of pre-deployment training to perceived deployed success of the orthopedic surgeons. From this extensive review, we found that explosive mechanisms of injury were greatly increased when compared to previous conflicts and were the etiology for the majority of orthopedic injuries sustained. With the increase of complex explosive injuries in the setting of improved body armor and overall survival, R2/3 facilities showed an increased demand for orthopedic intervention including debridement, amputations, and external fixation. Combat injuries sustained during the GWoT differ in the complications, management, and complexity when compared to civilian trauma. "Humanitarian" cases made up a significant number of operative cases for the deployed orthopedic surgeon. Lastly, heterogeneous training opportunities were available prior to deployment (fellowship, combat extremity surgical courses, and dedicated pre-deployment training), and the most commonly identified useful training was learning additional soft-tissue coverage techniques.

CONCLUSION

These major themes indicate an emphasis on pre-deployment training and the strategic positioning of orthopedic surgeons to reflect the changing landscape of musculoskeletal trauma care. Moving forward, these authors recommend analyzing the comfort and perceived capability of orthopedic surgeons in these unique military environments to best prepare for a changing operational format and the possibility of future peer-peer conflicts that will likely lead to a lack of medical evacuation and prolonged field care.

Isolated limb fractures - the underestimated injury in the Israeli Defence Forces (IDF)

INTRODUCTION

Musculoskeletal injuries dominate warfare-related trauma and differ from civilian settings in higher hospitalization costs, morbidity, and mortality. Partly due to introduction of personal protective equipment in the Israel Defence Force (IDF) to minimize head and torso injuries while the extremities remained unprotected. This study describes military extremity injury patterns, prehospital treatment and injury sequela regarding return-to-duty and disability compensation.

METHODS

This retrospective study examined cases of battle and non-battle trauma casualties treated by the IDF Medical Corps from 2013 to 2020. Data from the IDF Trauma Registry (IDF-TR) was merged with The Israeli National Trauma Registry (INTR). Cases with high morbidity discharged from military service were compared with lower morbidity patients who returned to active duty service.

RESULTS

Out of 1360 injured soldiers, 280 (20.6%) were found to have isolated limb fractures (ILFs). High morbidity casualties had more open fractures (63% vs. 42%) and higher involvement of lower extremities (79% vs. 58%) (p < 0.001), higher rates of tourniquets use (28% compared to 9%, p < 0.001), external fixation (34% vs. 19%, p < 0.001) and amputations (9% vs. 1%, p = 0.003), required more rehabilitation (34% vs. 7%, p < 0.001), and had 46% medical disabilities compared to 24% with low morbidity (p < 0.001).

CONCLUSIONS

ILFs are associated with significant morbidity and disability. High morbidity is associated with high energy, scar-producing, lower-extremity open fractured limbs treated by tourniquets. Future studies should evaluate whether junctional or extremity protective gear is combat feasible and whether introducing Clinical Practice Guidelines to manage suspected limb fractures can decrease morbidity rates and improve return to duty.

IDCRP Combat-Related Extremity Wound Infection Research

INTRODUCTION

Extremity trauma is the most common battlefield injury, resulting in a high frequency of combat-related extremity wound infections (CEWIs). As these infections are associated with substantial morbidity and may impact wounded warriors long after initial hospitalization, CEWIs have been a focus of the Infectious Disease Clinical Research Program (IDCRP). Herein, we review findings of CEWI research conducted through the IDCRP and discuss future and ongoing analyses.

METHODS

Military personnel with deployment-related trauma sustained between 2009 and 2014 were examined in retrospective analyses through the observational Trauma Infectious Disease Outcomes Study (TIDOS). Characteristics of wounded warriors with ≥1 open extremity wound were assessed, focusing on injury patterns and infection risk factors. Through a separate trauma-associated osteomyelitis study, military personnel with combat-related open fractures of the long bones (tibia, femur, and upper extremity) sustained between 2003 and 2009 were examined to identify osteomyelitis risk factors.

RESULTS

Among 1,271 wounded warriors with ≥1 open extremity wound, 16% were diagnosed with a CEWI. When assessed by their most severe extremity injury (i.e., amputation, open fracture, or open soft-tissue wound), patients with amputations had the highest proportion of infections (47% of 212 patients with traumatic amputations). Factors related to injury pattern, mechanism, and severity were independent predictors of CEWIs during initial hospitalization. Having a non-extremity infection at least 4 days before CEWI diagnosis was associated with reduced likelihood of CEWI development. After hospital discharge, 28% of patients with extremity trauma had a new or recurrent CEWI during follow-up. Risk factors for the development of CEWIs during follow-up included injury pattern, having either a CEWI or other infection during initial hospitalization, and receipt of antipseudomonal penicillin for ≥7 days. A reduced likelihood for CEWIs during follow-up was associated with a hospitalization duration of 15-30 days. Under the retrospective osteomyelitis risk factor analysis, patients developing osteomyelitis had higher open fracture severity based on Gustilo-Anderson (GA) and the Orthopaedic Trauma Association classification schemes and more frequent traumatic amputations compared to open fracture patients without osteomyelitis. Recurrence of osteomyelitis was also common (28% of patients with open tibia fractures had a recurrent episode). Although osteomyelitis risk factors differed between the tibia, femur, and upper extremity groups, sustaining an amputation, use of antibiotic beads, and being injured in the earlier years of the study (before significant practice pattern changes) were consistent predictors. Other risk factors included GA fracture severity ≥IIIb, blast injuries, foreign body at fracture site (with/without orthopedic implant), moderate/severe muscle damage and/or necrosis, and moderate/severe skin/soft-tissue damage. For upper extremity open fractures, initial stabilization following evacuation from the combat zone was associated with a reduced likelihood of osteomyelitis.

CONCLUSIONS

Forthcoming studies will examine the effectiveness of common antibiotic regimens for managing extremity deep soft-tissue infections to improve clinical outcomes of combat casualties and support development of clinical practice guidelines for CEWI treatment. The long-term impact of extremity trauma and resultant infections will be further investigated through both Department of Defense and Veterans Affairs follow-up, as well as examination of the impact on comorbidities and mental health/social factors.

The economic burden of open tibia fractures: A systematic review

BACKGROUND

Open tibia fractures are a common injury following road traffic collisions and place a large economic burden on patients and healthcare systems. Summarising their economic burden is key to inform policy and help prioritise treatment.

METHODS

All studies were identified from a systematic search of Medline, Embase and the Cochrane Central Register of Controlled Trials. We included any human with a diagnosed open tibia fracture, following any intervention. The primary outcome was any costs reported or patient return to work status. Secondary outcomes included average length of stay, wage loss, absenteeism and complications such as infection, amputation and nonunion. Data was extracted and we performed a descriptive narrative summary.

RESULTS

We reviewed 1,204 studies from our searches. A total of 34 studies were included from 14 different countries. The average age was 37.7 years old and 76% of the patients were male. 6.5% were Gustilo I, 12% Gustilo II and 82% Gustilo III. Initial direct hospitalisation costs were reported to be between £356 to £126,479 with an average length of stay of 56 days (3.1-244). 89% of participants were working pre-injury, 60% fully returned to work, 17% returned to work part time or changed profession and 22% did not return to work at one-year. The most common complications reported were 22% infection, 11% nonunion and 16% amputation. Mean follow-up duration for the studies was 25 months.

CONCLUSION

The economic burden of open tibia fractures varies greatly, but it is costly for both hospitals and patients. The current evidence is predominantly from high-income countries (HICs), especially the USA. Further research is required to investigate the costs of open tibia fractures using validated costing tools, especially in low-income countries (LICs), to help inform and direct policy.

Antibiotic Practice Patterns for Extremity Wound Infections among Blast-Injured Subjects

INTRODUCTION

We examined antibiotic management of combat-related extremity wound infections (CEWI) among wounded U.S. military personnel (2009-2012).

METHODS

Patients were included if they sustained blast injuries, resulting in ≥1 open extremity wound, were admitted to participating U.S. hospitals, developed a CEWI (osteomyelitis or deep soft-tissue infections) within 30 days post-injury, and received ≥3 days of relevant antibiotic (s) for treatment.

RESULTS

Among 267 patients, 133 (50%) had only a CEWI, while 134 (50%) had a CEWI plus concomitant non-extremity infection. In the pre-diagnosis period (4-10 days prior to CEWI diagnosis), 95 (36%) patients started a new antibiotic with 28% of patients receiving ≥2 antibiotics. During CEWI diagnosis week (±3 days of diagnosis), 209 (78%) patients started a new antibiotic (71% with ≥2 antibiotics). In the week following diagnosis (4-10 days after CEWI diagnosis), 121 (45%) patients started a new antibiotic with 39% receiving ≥2 antibiotics. Restricting to ±7 days of CEWI diagnosis, patients commonly received two (35%) or three (27%) antibiotics with frequent combinations involving carbapenem, vancomycin, and fluoroquinolones.

CONCLUSIONS

Substantial variation in antibiotic prescribing patterns related to CEWIs warrants development of combat-related clinical practice guidelines beyond infection prevention, to include strategies to reduce the use of unnecessary antibiotics and improve stewardship.

Osteomyelitis Risk Factors Related to Combat Trauma Open Upper Extremity Fractures: A Case-Control Analysis

OBJECTIVE

To determine risk factors for osteomyelitis in US military personnel with combat-related, extremity long bone (humerus, radius, and ulna) open fractures.

DESIGN

Retrospective observational case-control study.

SETTING

US military regional hospital in Germany and tertiary care military hospitals in the United States (2003-2009).

PATIENTS/PARTICIPANTS

Sixty-four patients with open upper extremity fractures who met diagnostic osteomyelitis criteria (medical record review verification) were classified as cases. Ninety-six patients with open upper extremity fractures who did not meet osteomyelitis diagnostic criteria were included as controls.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASUREMENTS

Multivariable odds ratios (ORs; 95% confidence interval [CI]).

RESULTS

Among patients with surgical implants, osteomyelitis cases had longer time to definitive orthopaedic surgery compared with controls (median: 26 vs. 11 days; P < 0.001); however, there was no significant difference with timing of radiographic union. Being injured between 2003 and 2006, use of antibiotic beads, Gustilo-Anderson [GA] fracture classification (highest with GA-IIIb: [OR: 22.20; CI: 3.60-136.95]), and Orthopaedic Trauma Association Open Fracture Classification skin variable (highest with extensive degloving [OR: 15.61; CI: 3.25-74.86]) were independently associated with osteomyelitis risk. Initial stabilization occurring outside of the combat zone was associated with reduced risk of osteomyelitis.

CONCLUSIONS

Open upper extremity fractures with severe soft-tissue damage have the highest risk of developing osteomyelitis. The associations with injuries sustained 2003-2006 and location of initial stabilization are likely from evolving trauma system recommendations and practice patterns during the timeframe.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Is Bone Loss or Devascularization Associated With Recurrence of Osteomyelitis in Wartime Open Tibia Fractures?

BACKGROUND

During recent wars, 26% of combat casualties experienced open fractures and these injuries frequently are complicated by infections, including osteomyelitis. Risk factors for the development of osteomyelitis with combat-related open tibia fractures have been examined, but less information is known about recurrence of this infection, which may result in additional hospitalizations and surgical procedures.

QUESTIONS/PURPOSES

(1) What is the risk of osteomyelitis recurrence after wartime open tibia fractures and how does the microbiology compare with initial infections? (2) What factors are associated with osteomyelitis recurrence among patients with open tibia fractures? (3) What clinical characteristics and management approaches are associated with definite/probable osteomyelitis as opposed to possible osteomyelitis and what was the microbiology of these infections?

METHODS

A survey of US military personnel injured during deployment between March 2003 and December 2009 identified 215 patients with open tibia fractures, of whom 130 patients developed osteomyelitis and were examined in a retrospective analysis. No patients with bilateral osteomyelitis were included. Twenty-five patients meeting osteomyelitis diagnostic criteria were classified as definite/probable (positive bone culture, direct evidence of infection, or symptoms with culture and/or radiographic evidence) and 105 were classified as possible (bone contamination, organism growth in deep wound tissue, and evidence of local/systemic inflammation). Patients diagnosed with osteomyelitis were treated with débridement and irrigation as well as intravenous antibiotics. Fixation hardware was retained until fracture union, when possible. Osteomyelitis recurrence was defined as a subsequent osteomyelitis diagnosis at the original site ≥ 30 days after completion of initial treatment. This followup period was chosen based on the definition of recurrence so as to include as many patients as possible for analysis. Factors associated with osteomyelitis recurrence were assessed using univariate analysis in a subset of the population with ≥ 30 days of followup. Patients who had an amputation at or proximal to the knee after the initial osteomyelitis were not included in the recurrence assessment.

RESULTS

Of 112 patients meeting the criteria for assessment of recurrence, 31 (28%) developed an osteomyelitis recurrence, of whom seven of 25 (28%) had definite/probable and 24 of 87 (28%) had possible classifications for their initial osteomyelitis diagnosis. Risk of osteomyelitis recurrence was associated with missing or devascularized bone (recurrence, 14 of 31 [47%]; nonrecurrence, 22 of 81 [28%]; hazard ratio [HR], 3.94; 1.12-13.81; p = 0.032) and receipt of antibiotics for 22-56 days (recurrence, 20 of 31 [65%]; nonrecurrence: 37 of 81 [46%]; HR, 2.81; 1.05-7.49; p = 0.039). Compared with possible osteomyelitis, definite/probable osteomyelitis was associated with localized swelling at the bone site (13 of 25 [52%] versus 28 of 105 [27%]; risk ratio [RR], 1.95 [1.19-3.19]; p = 0.008) and less extensive skin and soft tissue injury at the time of trauma (9 of 22 [41%; three definite/probably patients missing data] versus 13 of 104 [13%; one possible patient missing data]; RR, 3.27 [1.60-6.69]; p = 0.001). Most osteomyelitis infections were polymicrobial (14 of 23 [61%; two patients with missing data] for definite/probable patients and 62 of 105 [59%] for possible patients; RR, 1.03 [0.72-1.48]; p = 0.870). More of the definite/probable patients received vancomycin (64%) compared with the possible patients (41%; p = 0.046), and the duration of polymyxin use was longer (median, 38 days versus 16 days, p = 0.018). Time to definitive fracture fixation was not different between the groups.

CONCLUSIONS

Recurrent osteomyelitis after open tibia fractures is common. In a univariate model, patients with an intermediate amount of bone loss and those treated with antibiotics for 22 to 56 days were more likely to experience osteomyelitis recurrence. Because only univariate analysis was possible, these findings should be considered preliminary. Osteomyelitis recurrence rates were similar, regardless of initial osteomyelitis classification, indicating that diagnoses of possible osteomyelitis should be treated aggressively.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Is staged management with immediate conversion of external fixation to retrograde intramedullary nailing for combat-related Gustilo Type III supracondylar femur fractures safe and reliable method?

INTRODUCTION

Femur fractures due to bomb explosions and gunshots in battlefield require osseous stabilization as quickly as possible to expedite emergent conditions. İmmediate external fixation is the initial procedure as usual with planned early conversion to definitive treatment. The purpose of the current study is to determine the results of the early retrograde intramedullary nailing in combat-related injuries.

MATERIAL AND METHODS

Eighteen patients with comminuted supracondylar femur fractures, initially treated with external fixation followed by planned conversion to retrograde intramedullary nailing in a one-stage procedure, were evaluated in a retrospective review to gather demographic, injury, management, and fracture-healing data for analysis.

RESULTS

According to the system of Gustilo Anderson and Orthopedic Trauma Association, all fractures were open type III and 33-A3, respectively. The mean follow-up, operation time and union time were 1.8 years (range, 6 months to 2,6 years), 75 min (range, 60-100), and 3 months (range, 1.5-4), respectively. There was one complication of acute osteomyelitis which was successfully treated with antibiotic-load beams and aggressive bone debridement. No septic arthritis was observed.

CONCLUSIONS

We concluded that immediate retrograde intramedullary nailing in combat-related supracondylar femur fractures regardless of contamination even in Gustilo type III is a safe and reliable treatment method.

Infectious Complications After Deployment Trauma: Following Wounded US Military Personnel Into Veterans Affairs Care

Background

Infectious complications related to deployment trauma significantly contribute to the morbidity and mortality of wounded service members. The Trauma Infectious Disease Outcomes Study (TIDOS) collects data on US military personnel injured in Iraq and Afghanistan in an observational cohort study of infectious complications. Patients enrolled in TIDOS may also consent to follow-up through the Department of Veterans Affairs (VA). We present data from the first 337 TIDOS enrollees to receive VA healthcare.

Methods

Data were collected from the Department of Defense (DoD) Trauma Registry, TIDOS infectious disease module, DoD and VA electronic medical records, and telephone interview. Cox proportional hazard analysis was performed to identify predictors of post-discharge infections related to deployment trauma.

Results

Among the first 337 TIDOS enrollees who entered VA healthcare, 111 (33%) had 244 trauma-related infections during their initial trauma hospitalization (2.1 infections per 100 person-days). Following initial discharge, 127 (38%) enrollees had 239 trauma-related infections (170 during DoD follow-up and 69 during VA time). Skin and soft-tissue infections and osteomyelitis were predominant during and after the initial trauma hospitalization. In a multivariate model, a shorter time to development of a new infection following discharge was independently associated with injury severity score ≥10 and occurrence of ≥1 inpatient infection during initial trauma hospitalization.

Conclusions

Incident infections related to deployment trauma continue well after initial hospital discharge and into VA healthcare. Overall, 38% of enrolled patients developed a new trauma-related infection after their initial hospital discharge, with 29% occurring after the patient left military service.

Osteomyelitis Risk Factors Related to Combat Trauma Open Tibia Fractures: A Case-Control Analysis

OBJECTIVES

We assessed osteomyelitis risk factors in US military personnel with combat-related open tibia fractures (2003-2009).

METHODS

Patients with open tibia fractures who met the diagnostic criteria of osteomyelitis were identified as cases using Military Health System data and verified through medical record review. Controls were patients with open tibia fractures who did not meet osteomyelitis criteria. The Gustilo-Andersen fracture classification scheme was modified to include transtibial amputations (TTAs) as the most severe level. Logistic regression multivariable odds ratios [ORs; 95% confidence intervals (CI)] were assessed.

RESULTS

A total of 130 tibia osteomyelitis cases and 85 controls were identified. Excluding patients with TTAs, osteomyelitis cases had significantly longer time to radiographic union compared with controls (median: 210 vs. 165 days). Blast injuries, antibiotic bead utilization, ≥ Gustilo-Andersen-IIIb fractures [highest risk with TTA (OR: 15.10; CI: 3.22-71.07)], and foreign body at the fracture site were significantly associated with developing osteomyelitis. In a separate model, the Orthopaedic Trauma Association Open Fracture Classification muscle variable was significant with increasing risk from muscle loss (OR: 5.62; CI: 2.21-14.25) to dead muscle (OR: 8.46; CI: 3.31-21.64). When TTAs were excluded, significant risk factors were similar and included sustaining an injury between 2003 and 2006.

CONCLUSIONS

Patients with severe blast trauma resulting in significant muscle damage are at the highest risk for osteomyelitis. The period association coincides with a time frame when several trauma system practice changes were initiated (eg, increased negative pressure wound therapy, decreased high-pressure irrigation, and reduced crystalloid use).

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Infection with high proportion of multidrug-resistant bacteria in conflict-related injuries is associated with poor outcomes and excess resource consumption: a cohort study of Syrian patients treated in Jordan

Background

Armed conflicts are a major contributor to injury and death globally. Conflict-related injuries are associated with a high risk of wound infection, but it is unknown to what extent infection directly relates to sustainment of life and restoration of function. The aim of this study was to investigate the outcome and resource consumption among civilians receiving acute surgical treatment due to conflict-related injuries. Patients with and without wound infections were compared.

Methods

We performed a cohort study using routinely collected data from 457 consecutive Syrian civilians that received surgical treatment for acute conflict-related injuries during 2014–2016 at a Jordanian hospital supported by Médecins Sans Frontières. We defined wound infection as clinical signs of infection verified by a positive culture. We used logistic regression models to evaluate infection-related differences in outcome and resource consumption.

Results

Wound infection was verified in 49/457 (11%) patients. Multidrug-resistance (MDR) was detected in 36/49 (73%) of patients with infection. Among patients with infection, 11/49 (22%) were amputated, compared to 37/408 (9%) without infection, crude relative risk = 2.62 (95% confidence interval 1.42–4.81). Infected patients needed 12 surgeries on average, compared to five in non-infected patients (p < .00001). Mean length of stay was 77 days for patients with infection, and 35 days for patients without infection (p = .000001).

Conclusions

Among Syrian civilians, infected conflict-related wounds had a high prevalence of MDR bacteria. Wound infection was associated with poor outcomes and high resource consumption. These results could guide the development of antibiotic protocols and adaptations of surgical management to improve care for wound infections in conflict-related injuries.

Trial registration

ClinicalTrials.gov (NCT02744144). Registered April 13, 2016. Retrospectively registered.

Association of Enterococcus spp. with Severe Combat Extremity Injury, Intensive Care, and Polymicrobial Wound Infection

BACKGROUND

Combat-related extremity wound infections can complicate the recovery of injured military personnel. The Enterococcus genus contains both commensal and pathogenic bacteria found in many combat wounds. We describe the patient population susceptible to Enterococcus infection, the characteristics of Enterococcus spp. isolated from combat-related wounds, and the microbiological profile of Enterococcus-positive wounds.

METHODS

Patient and culture data were obtained from the Trauma Infectious Disease Outcomes Study. Subjects were divided into a case group with enterococcal extremity wound infections and a comparator group with wound infections caused by other micro-organisms.

RESULTS

Case and comparator subjects had similar patterns of injury and infection. Case subjects had higher Injury Severity Scores (33 vs. 30; p < 0.001), longer hospitalization at U.S. facilities (55 vs. 40 days; p = 0.004), and required more large-volume blood transfusions (>20 units) within 24 h post-injury (53% vs. 30%; p < 0.001). Approximately 60% of case subjects had three or more infections, and 91% had one or more polymicrobial infections, compared with 43% and 50%, respectively, in the comparator group. The thigh was the most common site of Enterococcus spp. isolation, contributing 50% of isolates. Enterococcus faecium was the predominant species isolated from case-group infections overall (66%), as well as in polymicrobial infections (74%). Frequent co-colonizing microbes in polymicrobial wound infections with Enterococcus were other ESKAPE pathogens (64%) (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae [and Escherichia coli], Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) and fungi (35%).

CONCLUSIONS

The specific pathogenicity of Enterococcus relative to other pathogens in polymicrobial wounds is unknown. Identifying strain-specific outcomes and investigating the interactions of Enterococcus strains with other wound pathogens could provide additional tools and strategies for infection mitigation in combat-related wounds.

Lymph node transfer for refractory infectious sites caused by trauma

OBJECTIVE

In this report, we placed focus on the immunological function of lymph nodes and performed lymph node transfer via a free flap to a site of refractory infection.

CASE AND RESULTS

Case 1 describes a 34-year-old male suffering from compound fractures with severe crush injuries and burns in the right ankle joint. A 20 × 15 cm skin defect was observed around the right malleolus medialis, along with denuded tendons with bacterial infection. After conservative treatment, we transferred a lymph-node-containing free superficial circumflex iliac artery perforator flap to the region, with minimum debridement. No recurrence of wound infection appeared. Case 2 describes a 73-year-old male patient suffering from extensive contused wound in the right crus. Despite conservative treatment, the tibia gradually became denuded with computed tomography and magnetic resonance imaging revealing degeneration of the tibial cortex. We performed a free superficial circumflex iliac artery perforator flap containing lymph nodes to the chronic infection area. The wound area healed successfully.

CONCLUSION

In conclusion, lymph node transfer has a potential of treatment infection sites.

Infection after fracture osteosynthesis - Part I

Bone and surgical site infections after osteosynthesis are notoriously difficult to manage and pose a tremendous burden in fracture management. In this article, we use the term osteosynthesis-associated infection (OAI) to refer to this clinical entity. While relatively few surgically treated fractures become infected, it is challenging to perform a rapid diagnosis. Optimal management strategies are complex and highly customized to each scenario and take into consideration the status of fracture union, the presence of hardware and the degree of mechanical stability. At present, a high level of relevant evidence is unavailable; most findings presented in the literature are based on laboratory work and non-randomized clinical studies. We present this overview of OAI in two parts: an examination of recent literature concerning OAI pathogenesis, diagnosis and classification and a review of treatment options.

Open Fracture Care During War: Opportunities for Research

Reported infection rates following severe open fractures of the lower extremity sustained in combat have varied widely, from 23% to 85%. The infection rates have been either similar to or higher than those reported in the civilian trauma literature. Deployed surgeons have increased the frequency of fasciotomy procedures for limbs with or at risk for clinical compartment syndrome. The long-term sequelae of compartment syndrome and fasciotomies are not clearly defined. The definition of the term late amputation has varied in the literature, and studies have not consistently included information on the causes of the amputations. Preclinical and clinical translational studies on the reduction of the rates of infection and other limb morbidities are needed to address the acute care of combat extremity wounds.

Lower Extremity Limb Salvage: Lessons Learned From 14 Years at War

American survivability during the current conflicts in Iraq and Afghanistan continues to improve, though the rate of extremity injury remains quite high. The decision to proceed with amputation versus limb salvage remains controversial. Exposure to combat wound with severe high-energy lower extremity trauma during the previous 14 years at war has incited important advances in limb salvage technique and rehabilitation.

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.

Rifamycin Derivatives Are Effective Against Staphylococcal Biofilms In Vitro and Elutable From PMMA

BACKGROUND

Local antimicrobial delivery through polymethylmethacrylate beads (PMMA), commonly vancomycin, is used for the treatment of contaminated open fractures but has limited activity against Staphylococcus aureus biofilms, which occur commonly in such fractures. Rifamycins have activity against biofilms and are an effective treatment for osteoarticular infections involving staphylococcal biofilms, but there are limited studies evaluating the activity of rifamycin derivatives, other than rifampin, against biofilms of S. aureus and evaluating incorporation of these drugs into PMMA for treatment of contaminated open fractures.

QUESTIONS/PURPOSES

(1) Are rifamycin derivatives effective against established biofilms of clinical isolates of S. aureus? (2) Can PMMA be used as a carrier for rifamycin derivatives?

METHODS

Biofilms were developed and evaluated for susceptibility to a panel of antimicrobials in vitro using the minimum biofilm eradication concentration high-throughput model. Susceptibility was assessed by measuring bacterial recovery at 6 and 24 hours after antimicrobial treatment. Activity of rifamycin derivatives against intracellular bacteria was also evaluated using a gentamicin protection assay. Evaluation of PMMA as a carrier for rifampin and rifamycin derivatives was determined by assessing the curing time subsequent to loading of rifamycins and characterizing the release kinetics of rifamycins at daily intervals for 14 days from PMMA by performing bioassays.

RESULTS

Rifamycin derivatives between 1 and 8 µg/mL reduced bacteria within biofilms 5- to 9-logs and prevented bacterial recovery up to 24 hours post-treatment, indicating near to complete eradication of biofilms. Rifamycin derivatives at 32 µg/mL had activity against intracellular staphylococci, significantly reducing the number of internalized bacteria with limited effects on osteoblast viability. Rifampin was the only rifamycin observed to have a suitable release profile from PMMA, releasing 49% of the total antibiotic and maintaining a sustained released profile up to 14 days at a mean 28 ± 6 μg/mL.

CONCLUSIONS

Rifampin can be incorporated into PMMA and eluted at concentrations effective against biofilms and intracellular staphylococci.

CLINICAL RELEVANCE

Our in vitro findings suggest that local delivery of rifampin may be an effective strategy for the prevention and/or treatment of open fractures where S. aureus biofilms might develop. Clinical studies are needed to characterize what role this approach might have in the prevention and treatment of infections involving biofilms.