Do Pedicle Screws That Terminate in the Costovertebral Joint Compromise Proximal Anchor Fixation in a Dual Growing Rod Construct?

INTRODUCTION: Growing rods (GRs) are used to treat early-onset scoliosis (EOS) recalcitrant to bracing and casting. Proximal anchor pullout, a known complication of GR constructs, can result in spinal cord injury if pedicle screw anchors are placed with a lateral-to-medial trajectory. To mitigate this risk, a more straightforward and potentially safer trajectory may result in screws that terminate within the costovertebral joint (CVJ). We asked, how often does CVJ placement occur and does this technique increase the rate of failure in GR constructs? METHODS: We retrospectively reviewed 35 patients with EOS treated with dual GR with >2-year follow-up excluding patients with skeletal dysplasia or history of previous posterior instrumentation. Patient demographics, radiographic parameters, and implant constructs were assessed. RESULTS: Of patients meeting the inclusion criteria, 18/35 (51%) were females with an average age of 7.96 (range: 4.0 to 15.2) years at surgery with a follow-up of 3.7 (range: 2.0 to 7.7) years. Five (14%) patients had idiopathic EOS, 5 (14%) had congenital EOS, 12 (34%) had neuromuscular EOS, 10 (29%) had syndromic scoliosis, and 3 (9%) had another etiology for EOS. Among 195 proximal pedicle screws placed, 19 (10%) terminated within the CVJ, and 13 patients (37%) had at least 1 CVJ screw. Two patients (6%) experienced unilateral proximal pullout. In both patients, the anchors on the affected side included 1 of 2 screws within the CVJ. Both patients had constructs that included 2 screws on the side that pulled out and 3 screws on the side that did not. None of the remaining 17 CVJ screws led to implant failure. CONCLUSION: Pedicle screw placement within the CVJ is common and does not appear to significantly contribute to proximal screw pullout; however, it may contribute to unilateral implant failure in constructs employing only 2 proximal screws, where 1 of those 2 screws terminates within the CVJ. Construct modifications should be considered in this scenario. LEVEL OF EVIDENCE: Level III.

The posterior tibial slope and Insall-Salvati index in operative and nonoperative adolescent athletes with Osgood-Schlatter disease.

INTRODUCTION: Osgood-Schlatter disease (OSD) is a common cause of anterior knee pain in adolescent athletes due to repetitive stress on the tibial tubercle. The posterior tibial slope angle (PTSA) and the Insall-Salvati Index (ISI) play a role in knee biomechanics. However, to our knowledge, the posterior tibial slope and patellar height have not been compared in operated versus nonoperative OSD patients. The purpose of the current study is to compare the differences in the PTSA and the ISI between operative and nonoperative patients with OSD. MATERIALS AND METHODS: The study was approved by the College of Medicine's Institutional Review Board. A retrospective review was performed on 75 adolescent athletes with OSD between 2008 and 2019. The data extracted included: age, sex, body mass index (BMI), sporting activity and type, mechanism of injury (MOI), chronicity of symptoms, PTSA, and the ISI. Descriptive and quantitative statistics were used. RESULTS: Seventy-five patients (88 knees) with OSD were studied (28 boys, 47 girls). The average age was 12.2 years and the average BMI was 22.3. The mechanism of injury (MOI) included repetitive stress (77%) and trauma (23%). The duration of knee pain averaged 10.3 months. Sixty-six patients were included in the nonoperative cohort. Nine patients were included in the operative cohort and underwent surgery due to persistent symptoms after skeletal maturity with tubercleplasty and/or ossicle excision. The average PTSA was 12.1° ± 1.7° and average ISI was 1.05 ± 0.15. Comparing the operative and nonoperative patients, we found no significant difference in PTSA (11.2° ± 0.73° versus 12.8° ± 1.8°, p < 0.064). However, we did find that patients treated operatively had a lower ISI (0.95 ± 0.18 versus 1.14 ± 0.13, p < 0.001). CONCLUSION: In patients with OSD, operative and nonoperative patients demonstrated a similar PTSA. On the other hand, the ISI was higher in nonoperative patients. In the current paper, a decreased ISI was helpful in predicting the need for operative intervention in symptomatic patients after skeletal maturity.

Risk of Acute Kidney Injury in Combat-Injured Patients Associated With Concomitant Vancomycin and Extended-Spectrum ß-Lactam Antibiotic Use.

BACKGROUND: Multidrug-resistant infections complicating combat-related trauma necessitate the use of broad-spectrum antimicrobials. Recent literature posits an association between vancomycin (VANC) and piperacillin-tazobactam (VPT) combination therapy and acute kidney injury (AKI). We examined whether therapy with VPT was associated with an increased risk of AKI compared to VANC and other broad-spectrum ß-lactam antibiotics (VBL) following combat-related injuries. METHODS: Patients within the Trauma Infectious Disease Outcomes Study (TIDOS) who received ≥48 hours concomitant VPT or VBL started within 24 hours of each other were assessed. Exclusion criteria were receipt of renal replacement therapy and baseline creatinine >1.5 mg/dL. Acute kidney injury was defined by meeting any of the Risk, Injury, Failure, Loss, End Stage Renal Disease (RIFLE), AKIN, or VANC consensus guidelines criteria 3 to 7 days after therapy initiation. Variables significantly associated with AKI were used in inverse probability treatment weighting to perform univariate and subsequent logistic regression multivariate modeling to determine significant risk factors for AKI. RESULTS: Sixty-one patients who received VPT and 207 who received VBL were included. Both groups had a median age of 24 years and initial median creatinine of 0.7 mg/dL. The VBL patients were more likely to have sustained blast injuries (P = .001) and received nephrotoxic agents (amphotericin [P = .002] and aminoglycosides [P < .001]). In the VBL group, AKI incidence was 9.7% compared to 13.1% in the VPT group (P = .438). Multivariate analysis identified a relative risk of 1.727 (95% CI: 1.027-2.765) for AKI associated with VPT exposure. Acute kidney injury severity generally met RIFLE Risk criteria and was 1 day in duration. Only 1 patient had persistent renal dysfunction 30 days after therapy completion. CONCLUSION: In this young and previously healthy, severely ill combat-injured population, VPT was associated with nearly twice the risk of AKI compared to VBL. Nevertheless, AKI was of low severity, short duration, and had high rates of renal recovery.

Do Battlefield Injury-acquired Indwelling Metal Fragments Induce Metal Immunogenicity?

BACKGROUND: A battlefield-related injury results in increased local and systemic innate immune inflammatory responses, resulting in wound-specific complications and an increased incidence of osteoarthritis. However, little is known about whether severe injuries affect long-term systemic homeostasis, for example, immune function. Moreover, it also remains unknown whether battlefield-acquired metal fragments retained over the long term result in residual systemic effects such as altered immune reactivity to metals. QUESTIONS/PURPOSES: Does a retained metal fragment from a battlefield injury contribute to increased (1) adaptive metal-specific immune responses, (2) systemically elevated metal ion serum levels, and (3) serum immunoglobulin levels compared with combat injuries that did not result in a retained metal fragment? METHODS: In this pilot study, we analyzed metal-immunogenicity in injured military personnel and noninjured control participants using lymphocyte transformation testing (LTT, lymphocyte proliferation responses to cobalt, chromium and nickel challenge at 0.001, 0.01 and 0.1-mM concentrations in triplicate for each participant), serum metal ion analysis (ICP-mass spectroscopy), and serum immunoglobulin analysis (IgE, IgG, IgA, and IgM ). Military personnel with a battlefield-sustained injury self-recruited without any exclusion for sex, age, degree of injury. Those with battlefield injury resulting in retained metal fragments (INJ-FRAG, n = 20 male, mean time since injury ± SD was 12 ± 10 years) were compared with those with a battlefield injury but without retained metal fragments (INJ-NO-FRAG, n = 12 male, mean time since injury ± SD was 13 ± 12 years). A control group comprised of male noninjured participants was used to compare measured immunogenicity metrics (n = 11, males were selected to match battlefield injury group demographics). RESULTS: Military participants with sustained metal fragments had increased levels of metal-induced lymphocyte responses. The lymphocyte stimulation index among military participants with metal fragments was higher than in those with nonretained metal fragments (stimulation index = 4.2 ± 6.0 versus stimulation index = 2.1 ± 1.2 (mean difference 2.1 ± 1.4 [95% confidence interval 5.1 to 0.8]; p = 0.07) and an average stimulation index = 2 ± 1 in noninjured controls. Four of 20 participants injured with retained fragments had a lymphocyte proliferation index greater than 2 to cobalt compared with 0 in the group without a retained metal fragment or 0 in the control participants. However, with the numbers available, military personnel with retained metal fragments did not have higher serum metal ion levels than military participants without retained metal fragment-related injuries or control participants. Military personnel with retained metal fragments had lower serum immunoglobulin levels (IgG, IgA, and IgM) than military personnel without retained metal fragments and noninjured controls, except for IgE. Individuals who were metal-reactive positive (that is, a stimulation index > 2) with retained metal fragments had higher median IgE serum levels than participants who metal-reactive with nonmetal injuries (1198 ± 383 IU/mL versus 171 ± 67 IU/mL, mean difference 1027 ± 477 IU/mL [95% CI 2029 to 25]; p = 0.02). CONCLUSIONS: We found that males with retained metal fragments after a battlefield-related injury had altered adaptive immune responses compared with battlefield-injured military personnel without indwelling metal fragments. Military participants with a retained metal fragment had an increased proportion of group members and increased average lymphocyte reactivity to common implant metals such as nickel and cobalt. Further studies are needed to determine a causal association between exposure to amounts of retained metal fragments, type of injury, personnel demographics and general immune function/reactivity that may affect personal health or future metal implant performance. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Classification of Trauma-Associated Invasive Fungal Infections to Support Wound Treatment Decisions.

To evaluate a classification system to support clinical decisions for treatment of contaminated deep wounds at risk for an invasive fungal infection (IFI), we studied 246 US service members (413 wounds) injured in Afghanistan (2009-2014) who had laboratory evidence of fungal infection. A total of 143 wounds with persistent necrosis and laboratory evidence were classified as IFI; 120 wounds not meeting IFI criteria were classified as high suspicion (patients had localized infection signs/symptoms and had received antifungal medication for >10 days), and 150 were classified as low suspicion (failed to meet these criteria). IFI patients received more blood than other patients and had more severe injuries than patients in the low-suspicion group. Fungi of the order Mucorales were more frequently isolated from IFI (39%) and high-suspicion (21%) wounds than from low-suspicion (9%) wounds. Wounds that did not require immediate antifungal therapy lacked necrosis and localized signs/symptoms of infection and contained fungi from orders other than Mucorales.

Molecular Detection of Filamentous Fungi in Formalin-Fixed Paraffin-Embedded Specimens in Invasive Fungal Wound Infections Is Feasible with High Specificity.

Trauma-related invasive fungal wound infections (IFIs) are associated with significant morbidity and mortality. Early identification and treatment are critical. Traditional identification methods (e.g., fungal cultures and histopathology) can be delayed and insensitive. We assessed a PCR-based sequencing assay for rapid identification of filamentous fungi in formalin-fixed paraffin-embedded (FFPE) specimens obtained from combat casualties injured in Afghanistan. Blinded FFPE specimens from cases (specimens positive on histopathology) and controls (specimens negative on histopathology) were submitted for evaluation with a panfungal PCR. The internal transcribed spacer 2 (ITS2) region of the fungal ribosomal repeat was amplified and sequenced. The PCR results were compared with findings from histopathology and/or culture. If injury sites contributed multiple specimens, findings for the site were collapsed to the site level. We included 64 case subjects (contributing 95 sites) and 102 controls (contributing 118 sites). Compared to histopathology, panfungal PCR was specific (99%), but not as sensitive (63%); however, sensitivity improved to 83% in specimens from sites with angioinvasion. Panfungal PCR identified fungi of the order Mucorales in 33 of 44 sites with angioinvasion (75%), whereas fungal culture was positive in 20 of 44 sites (45%). Saksenaea spp. were the dominant fungi identified by PCR in specimens from angioinvasion sites (57%). Panfungal PCR is specific, albeit with lower sensitivity, and performs better at identifying fungi of the order Mucorales than culture. DNA sequencing offers significant promise for the rapid identification of fungal infection in trauma-related injuries, leading to more timely and accurate diagnoses.

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.

Delaminated Patellar Tendon Rupture in a Pediatric Patient: A Case Report.

CASE: We present a 12-year-old boy with partial delamination of the patellar tendon in the coronal plane and bipolar avulsion fracture of the tibial tubercle and patella after a planting injury while skateboarding. Pediatric patellar tendon rupture with associated bipolar avulsion fractures is rare. Furthermore, to the best of our knowledge, a delamination injury pattern of the patellar tendon has not been described. CONCLUSION: This type of extensor mechanism injury has not been reported in the literature. Repair with Krackow sutures and suture-bone tunnel technique, with consideration of the proximal tibial physis, is a safe and effective way to fix this unique pathology.

Neurophysiological Intraoperative Monitoring in Patients with Cochlear Implant Undergoing Posterior Spinal Fusion: A Case Report.

CASE: Transcranial electric stimulation motor-evoked potentials (tcMEPs) are the most sensitive technique in multimodality intraoperative neuromonitoring (IONM) for posterior spinal fusion (PSF). The presence of a cochlear implant (CI) is considered a contraindication to IONM because of theoretical risk of implant device and local tissue damage from voltages induced by tcMEPs. We present the case of a 10-year-old girl with CI who underwent successful PSF with tcMEP and monopolar electrocautery (MoEC) without perioperative complications or CI damage. CONCLUSION: With proper precautions, such as MoEC usage at a minimal voltage, motor-evoked potential monitoring can be safely performed in pediatric patients with CI undergoing PSF.

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.

Tips and tricks to avoid implant failure in proximal femur fractures treated with cephalomedullary nails: a review of the literature.

Objective: To describe the surgical aspects potentially contributing to hardware failure of cephalomedullary nails. Data Sources: A search of the Embase, PubMed (MEDLINE), Web of Science, and the Cochrane library for reports of hardware failures after intramedullary fixation of proximal femur fractures. Issues of cut out and cut through phenomena related to technique were excluded. Expert opinion of 3 surgeons, each trained on several fixation systems at Level | trauma centers is reported. Data Extraction: Three authors extracted data using a predesigned form. Implant type, reported failure mechanism, and associated factors with implant failure were recorded as well as potential bias. Results: Of 2182 search results screened, 64 articles were deemed relevant for our research question and were included. The authors identified factors associated with implant failure: preoperative patient and fracture characteristics, intraoperative reduction, implant handling, and postoperative nonunion. Issues were identified as independent modifiable intraoperative risk factors: inadequate fracture reduction, varus position of femoral neck, direct damage of the cephalomedullary nail aperture by eccentric drilling related to guide sleeve handling, and implant design mechanism failures. Conclusions: Multiple factors associated with intraoperative handling can influence the healing of proximal femur fractures. Although many of these have been well described and are taught in fracture courses, surgeons should be aware of subtle intraoperative complications reported in the literature that can weaken implants and add to the likelihood of early failure.Level of Evidence: IV.

Complications following surgical treatment of adolescent idiopathic scoliosis: a 10-year prospective follow-up study.

BACKGROUND: Accurate reporting of long-term complications of surgical treatment of adolescent idiopathic scoliosis (AIS) is critical, but incomplete. This study aimed to report on the rate of complications following surgical treatment of AIS among patients with at least 10 years of follow-up. METHODS: This was a retrospective review of prospectively collected data from a multicenter registry of patients who underwent surgical treatment for AIS with minimum 10-year follow-up. Previously published complications were defined as major if they resulted in reoperation, prolonged hospital stay/readmission, neurological deficits, or were considered life-threatening. Rates and causes of reoperations were also reviewed. RESULTS: Two hundred and eighty-two patients were identified with mean age at surgery of 14.6 ± 2.1 years. Mean follow-up was 10.6 (range 9.5-14) years. Eighty-seven patients had anterior spinal fusion (ASF); 195 had posterior spinal fusion (PSF). The overall major complication rate was 9.9% (n = 28) in 27 patients. Among PSF patients, the complication rate was 9.7% (n = 19) in 18 patients. The complications were surgical site infection (37%), adding-on (26%), pulmonary (16%), neurologic (11%), instrumentation (5%), and gastrointestinal (5%). In ASF patients, the complication rate was 10.3% (n = 9) among nine patients. The complications were pulmonary (44%), pseudoarthrosis (22%), neurologic (11%), adding-on (11%), and gastrointestinal (11%). The reoperation rate was 6.0% (n = 17) among 17 patients. Although most of the complications presented within the first 2 years (60.7%), surgical site infection and adding-on were also seen late into the 10-year period. CONCLUSION: This is the largest prospective study with at least a 10-year follow-up of complications following spinal fusion for AIS, the overall major complication rate was 9.9% with a reoperation rate of 6.0%. Complications presented throughout the 10-year period, making long-term follow-up very important for surveillance. LEVEL OF EVIDENCE: Therapeutic II.

Resistance patterns and clinical outcomes of Klebsiella pneumoniae and invasive Klebsiella variicola in trauma patients.

Recent reclassification of the Klebsiella genus to include Klebsiella variicola, and its association with bacteremia and mortality, has raised concerns. We examined Klebsiella spp. infections among battlefield trauma patients, including occurrence of invasive K. variicola disease. Klebsiella isolates collected from 51 wounded military personnel (2009-2014) through the Trauma Infectious Disease Outcomes Study were examined using polymerase chain reaction (PCR) and pulsed-field gel electrophoresis. K. variicola isolates were evaluated for hypermucoviscosity phenotype by the string test. Patients were severely injured, largely from blast injuries, and all received antibiotics prior to Klebsiella isolation. Multidrug-resistant Klebsiella isolates were identified in 23 (45%) patients; however, there were no significant differences when patients with and without multidrug-resistant Klebsiella were compared. A total of 237 isolates initially identified as K. pneumoniae were analyzed, with 141 clinical isolates associated with infections (remaining were colonizing isolates collected through surveillance groin swabs). Using PCR sequencing, 221 (93%) isolates were confirmed as K. pneumoniae, 10 (4%) were K. variicola, and 6 (3%) were K. quasipneumoniae. Five K. variicola isolates were associated with infections. Compared to K. pneumoniae, infecting K. variicola isolates were more likely to be from blood (4/5 versus 24/134, p = 0.04), and less likely to be multidrug-resistant (0/5 versus 99/134, p<0.01). No K. variicola isolates demonstrated the hypermucoviscosity phenotype. Although K. variicola isolates were frequently isolated from bloodstream infections, they were less likely to be multidrug-resistant. Further work is needed to facilitate diagnosis of K. variicola and clarify its clinical significance in larger prospective studies.

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.

Microbiology of combat-related extremity wounds: Trauma Infectious Disease Outcomes Study.

We present extremity wound microbiology data from 250 combat casualties (2009-2012). Confirmed extremity wound infections (EWIs) were based on clinical and laboratory findings. Suspected EWIs had isolation of organisms from wound cultures with associated signs/symptoms not meeting clinical diagnostic criteria. Colonized wounds had organisms isolated without any infection suspicion. A total of 335 confirmed EWIs (131 monomicrobial and 204 polymicrobial) were assessed. Gram-negative bacteria were predominant (57% and 86% of monomicrobial and polymicrobial infections, respectively). In polymicrobial infections, 61% grew only bacteria, while 30% isolated bacteria and mold. Multidrug resistance was observed in 32% of isolates from first monomicrobial EWIs ±3 days of diagnosis, while it was 44% of isolates from polymicrobial EWIs. Approximately 96% and 52% of the suspected and colonized wounds, respectively, shared ≥1 organism in common with the confirmed EWI on the same patient. Understanding of combat-related EWIs can lead to improvements in combat casualty care.

Combat-Related Extremity Wounds: Injury Factors Predicting Early Onset Infections.

We examined risk factors for combat-related extremity wound infections (CEWI) among U.S. military patients injured in Iraq and Afghanistan (2009-2012). Patients with ≥1 combat-related, open extremity wound admitted to a participating U.S. hospital (≤7 days postinjury) were retrospectively assessed. The population was classified based upon most severe injury (amputation, open fracture without amputation, or open soft-tissue injury defined as non-fracture/non-amputation wounds). Among 1271 eligible patients, 395 (31%) patients had ≥1 amputation, 457 (36%) had open fractures, and 419 (33%) had open soft-tissue wounds as their most severe injury, respectively. Among patients with traumatic amputations, 100 (47%) developed a CEWI compared to 66 (14%) and 12 (3%) patients with open fractures and open soft-tissue wounds, respectively. In a Cox proportional hazard analysis restricted to CEWIs ≤30 days postinjury among the traumatic amputation and open fracture groups, sustaining an amputation (hazard ratio: 1.79; 95% confidence interval: 1.25-2.56), blood transfusion ≤24 hours postinjury, improvised explosive device blast, first documented shock index ≥0.80, and >4 injury sites were independently associated with CEWI risk. The presence of a non-extremity infection at least 4 days prior to a CEWI diagnosis was associated with lower CEWI risk, suggesting impact of recent exposure to directed antimicrobial therapy. Further assessment of early clinical management will help to elucidate risk factor contribution. The wound classification system provides a comprehensive approach in assessment of injury and clinical factors for the risk and outcomes of an extremity wound infection.

Urinary Tract Infections after Combat-Related Genitourinary Trauma.

Background: We examined clinical outcomes among combat casualties with genitourinary injuries after blast trauma. Methods: Characteristics, clinical care, urologic complications, and infections for subjects enrolled in the Trauma Infectious Disease Outcomes Study (TIDOS) were collected from Department of Defense (DOD) and Department of Veterans Affairs (VA) sources. Logistic regression identified predictors for urinary tract infections (UTIs) after genitourinary trauma. Results: Among 530 TIDOS enrollees who entered VA care, 89 (17%) sustained genitourinary trauma. The majority of subjects (93%) were injured via a blast and 27% had a dismounted complex blast injury (DCBI). Sexual dysfunction was reported with 36% of subjects, whereas 14% had urinary retention/incontinence and 8% had urethral stricture. Urologic complications were comparable between patients with and without DCBIs. Nineteen (21%) subjects had one or more UTI with a total of 40 unique UTI events (25% during initial hospitalization and 75% during subsequent DOD or VA care). The UTI incidence rate was 0.89 per patient-year during initial hospitalization, 0.05 per patient-year during DOD follow-up, and 0.07 per patient-year during VA healthcare. Subjects with UTIs had a higher proportion of bladder injury (53% vs. 13%; p < 0.001), posterior urethral injury (26% vs. 1%; p = 0.001), pelvic fracture (47% vs. 4%; p < 0.001), soft-tissue infection of the pelvis/hip (37% vs. 4%; p = 0.001), urinary catheterization (47% vs. 11%; p < 0.001), urinary retention or incontinence (42% vs. 6%; p < 0.001), and stricture (26% vs. 3%; p = 0.004) compared with patients with genitourinary trauma and no UTI. Independent UTI risk factors were occurrence of a soft-tissue infection at the pelvis/hip, trauma to the urinary tract, and transtibial amputation. Conclusions: Among combat casualties with genitourinary trauma, UTIs are a common complication, particularly with severe blast injury and urologic sequelae. Episodes of UTIs typically occur early after the initial injury while in DOD care, however, recurrent infections may continue into long-term VA care.

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

OBJECTIVES: To identify the risk factors for osteomyelitis development in US military personnel with combat-related, open femur fractures? DESIGN: Retrospective observational case-control study. SETTING: US military regional hospital in Germany and tertiary care hospitals in United States (2003-2009). PATIENTS/PARTICIPANTS: One hundred three patients with open femur fractures who met diagnostic osteomyelitis criteria (medical record review verification) were classified as cases. Sixty-four patients with open femur fractures who did not meet osteomyelitis diagnostic criteria were included as controls. MAIN OUTCOME MEASUREMENTS: The main outcome measurements were multivariable odds ratios (ORs) and 95% confidence interval (CI). RESULTS: Among patients with surgical implants, osteomyelitis cases had significantly longer time to definitive orthopaedic surgery compared with controls (median: 21 vs. 13 days). Independent predictors for osteomyelitis risk were Gustilo-Anderson classification (transfemoral amputation OR: 19.3; CI: 3.0-123.0) and Orthopaedic Trauma Association Open Fracture Classification for muscle loss (OR: 5.7; CI: 1.3-25.1) and dead muscle (OR: 32.9; CI: 5.4-199.1). Being injured between 2003 and 2006, antibiotic bead use, and foreign body plus implant(s) at fracture site were also risk factors. CONCLUSIONS: Patients with open femur fractures resulting in significant muscle damage have the highest osteomyelitis risk. Foreign body contamination was only significant when an implant was present. Increased risk with antibiotic bead use is likely a surrogate for clinical suspicion of contamination with complex wounds. The timeframe association is likely due to changing trauma system patterns around 2006-2007 (eg, increased negative pressure wound therapy, reduced high-pressure irrigation, decreased crystalloid use, and delayed definitive internal fixations). LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

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.

After the Battlefield: Infectious Complications among Wounded Warriors in the Trauma Infectious Disease Outcomes Study.

INTRODUCTION: During recent wars in Iraq and Afghanistan, improved survivability in severe trauma corresponded with a rise in the proportion of trauma-related infections, including those associated with multidrug-resistant organisms (MDROs). Significant morbidity was reported in association with the infections. There is also concern regarding potential long-term impacts of the trauma-related infectious complications. Therefore, to meet the critical need of prospective collection of standardized infection-related data to understand the disease burden and improve outcomes of wounded personnel, the Trauma Infectious Disease Outcomes Study (TIDOS) was developed. Herein, we review accomplishments and key peer-reviewed findings of TIDOS. METHODS: The TIDOS project is a multicenter observational study of short- and long-term infectious complications following deployment-related trauma. Wounded military personnel medevac'd to Landstuhl Regional Medical Center (LRMC; Germany) before transfer to a participating US military hospital between June 2009 and December 2014 were eligible for inclusion. An infectious disease module to supplement the Department of Defense Trauma Registry by collecting infection-related data from all trauma patients admitted to participating hospitals was developed. Specimens from trauma patients were also collected and retained in a microbiological isolate repository. During the initial hospitalization, patients were given the opportunity to enroll in a prospective follow-up cohort study. Patients who received Department of Veterans Affairs (VA) care were also given the opportunity to consent to ongoing VA follow-up. RESULTS: A total of 2,699 patients transferred to participating military hospitals in the USA, of which 1,359 (50%) patients enrolled in the TIDOS follow-up cohort. In addition, 638 enrolled in the TIDOS-VA cohort (52% of TIDOS enrollees who entered VA healthcare). More than 8,000 isolates were collected from infection control surveillance and diagnostic evaluations and retained in the TIDOS Microbiological Repository. Approximately 34% of the 2,699 patients at US hospitals developed a trauma-related infection during their initial hospitalization with skin and soft-tissue infections being predominant. After discharge from the US hospitals, approximately one-third of TIDOS cohort enrollees developed a new trauma-related infection during follow-up and extremity wound infections (skin and soft-tissue infections and osteomyelitis) continued to be the majority. Among TIDOS cohort enrollees who received VA healthcare, 38% developed a new trauma-related infection with the incident infection being diagnosed a median of 88 days (interquartile range: 19-351 days) following hospital discharge. Data from TIDOS have been used to support the development of Joint Trauma System clinical practice guidelines for the prevention of combat-related infections, as well as the management of invasive fungal wound infections. Lastly, due to the increasing proportion of infections associated with MDROs, TIDOS investigators have collaborated with investigators across military laboratories as part of the Multidrug-Resistant and Virulent Organisms Trauma Infections Initiative with the objective of improving the understanding of the complex wound microbiology in order to develop novel infectious disease countermeasures. CONCLUSIONS: The TIDOS project has focused research on four initiatives: (1) blast-related wound infection epidemiology and clinical management; (2) DoD-VA outcomes research; (3) Multidrug- Resistant and other Virulent Organisms Trauma Infections Initiative; and (4) Joint Trauma System clinical practice guidelines and antibiotic stewardship. There is a continuing need for longitudinal data platforms to support battlefield wound research and clinical practice guideline recommendation refinement, particularly to improve care for future conflicts. As such, maintaining a research platform, such as TIDOS, would negate the lengthy time needed to initiate data collection and analysis.