Characterization of extremity wounds in Operation Iraqi Freedom and Operation Enduring Freedom

Development of a Bayesian model to estimate health care outcomes in the severely wounded

BACKGROUND

Graphical probabilistic models have the ability to provide insights as to how clinical factors are conditionally related. These models can be used to help us understand factors influencing health care outcomes and resource utilization, and to estimate morbidity and clinical outcomes in trauma patient populations.

STUDY DESIGN

Thirty-two combat casualties with severe extremity injuries enrolled in a prospective observational study were analyzed using step-wise machine-learned Bayesian belief network (BBN) and step-wise logistic regression (LR). Models were evaluated using 10-fold cross-validation to calculate area-under-the-curve (AUC) from receiver operating characteristics (ROC) curves.

RESULTS

Our BBN showed important associations between various factors in our data set that could not be developed using standard regression methods. Cross-validated ROC curve analysis showed that our BBN model was a robust representation of our data domain and that LR models trained on these findings were also robust: hospital-acquired infection (AUC: LR, 0.81; BBN, 0.79), intensive care unit length of stay (AUC: LR, 0.97; BBN, 0.81), and wound healing (AUC: LR, 0.91; BBN, 0.72) showed strong AUC.

CONCLUSIONS

A BBN model can effectively represent clinical outcomes and biomarkers in patients hospitalized after severe wounding, and is confirmed by 10-fold cross-validation and further confirmed through logistic regression modeling. The method warrants further development and independent validation in other, more diverse patient populations.

Stability of antibacterial self-assembled monolayers on hydroxyapatite

Open fractures are common in battlefields, motor vehicle accidents, gunshot wounds, sports injuries, and high-energy falls. Such fractures are treated using hydroxyapatite (HA)-based bone graft substitutes. However, open fracture wounds are highly susceptible to bacterial infections. Hence, this study was focused on incorporating antibacterial properties to HA using silver (Ag) carrying self-assembled monolayers (SAMs). Also, the stability of Ag carrying SAMs on HA was investigated under sterilization and physiological conditions. Initially, the -COOH terminated phosphonic acid SAMs of two different chain lengths (11 carbon atoms - shorter chain and 16 carbon atoms - longer chain) were deposited on HA. Antibacterial SAMs (ASAMs) were prepared by chemically attaching Ag to shorter and longer chain SAMs coated HA. X-ray photoelectron spectroscopy, atomic force microscopy, and contact angle goniometry collectively confirmed the attachment of Ag onto SAMs coated HA. The bacterial adhesion study showed that the adherence of Staphylococcus aureus was significantly reduced on ASAMs coated HA when compared to control-HA. The stability studies showed that gas plasma, dry heat and autoclave degraded most of the ASAMs on HA. UV irradiation did not damage the shorter chain ASAMs as vigorously as other treatments, while it degraded the longer chain ASAMs completely. Ethylene oxide treatment did not degrade the longer chain ASAMs unlike all other treatments but it severely damaged the shorter chain ASAMs. Both shorter and longer chain ASAMs significantly desorbed from the HA surfaces under physiological conditions although longer chain ASAMs exhibited better stability than shorter chain ASAMs. This study demonstrated the potential for using ASAMs to provide antibacterial properties to HA and the need for developing techniques to improve stability of SAMs under sterilization and physiological conditions.

Functional assessment of skeletal muscle regeneration utilizing homologous extracellular matrix as scaffolding

The loss of a portion of skeletal muscle poses a unique challenge for the normal regeneration of muscle tissue. A transection injury with tissue loss will not heal due to the gap between muscle segments. A damage model was developed by removing a portion of the lateral gastrocnemius (GAS) of Sprague-Dawley rats. Maximal isometric, tetanic tension (P(o)) was measured after the removal of either a small defect (0.5 x 1.0 cm) or a large defect (1.0 x 1.0 cm) piece of the GAS. In situ P(o) immediately after creation of the defect was 88.3 +/- 2.0% of the nonoperated contralateral GAS force for small defect and 76.9 +/- 3.2% of control for large defect. No functional recovery occurred in either group over the course of 28 days. To enhance recovery, a homologous, decellularized, muscle extracellular matrix (ECM) was implanted into the 1 x 1 cm defect of the lateral GAS of Lewis rats. After 42 days, growth of blood vessels and myofibers into the ECM was apparent, but no restoration of P(o) occurred. These data demonstrate the ability of the ECM to support muscle and blood vessel regeneration, but full recovery of function does not occur after 42 days.

Amputation and the assessment of limb viability: perceptions of two hundred and thirty two orthopaedic trainees

INTRODUCTION

The management of complex extremity injury, which may require assessment of limb viability and performance of amputation, is a challenge to those involved in its emergent and definitive care. Concern exists regarding the exposure of orthopaedic trainees to such cases due both to changes in training and centralisation of trauma services.

SUBJECTS AND METHODS

This is a web-based observational study by survey, investigating the confidence and perceived adequacy of training of UK orthopaedic specialist trainees in the assessment of limb viability and amputation surgery. 222 responses from 888 trainees were required to achieve a < 5% error rate with 90% confidence; 232 surveys were completed.

RESULTS

Trainee confidence in dealing with the assessment of limb viability is high despite infrequent exposure to cases. The majority of trainees perceive their training in limb viability assessment as adequate. For performance of amputation, exposure is minimal, confidence is lower and 36% of trainees regard their training as inadequate.

CONCLUSIONS

Limb viability assessment is an area in which trainees feel confident and well trained. There is, however, a perceived training inadequacy in amputation surgery and a corresponding lack of confidence for many trainees, irrespective of training year. This is the first study to offer an insight into specific training experiences of junior orthopaedic surgeons at a national level and it should drive the development of opportunities for trainees to develop skills in amputation surgery.

Neurosurgery in Afghanistan during “Operation Enduring Freedom”: a 24-month experience

Object

“Operation Enduring Freedom” is the US war effort in Afghanistan in its global war on terror. One US military neurosurgeon is deployed in support of Operation Enduring Freedom to provide care for both battlefield injuries and humanitarian work. Here, the authors analyze a 24-month neurosurgical caseload experience in Afghanistan.

Methods

Operative logs were analyzed between October 2007 and September 2009. Operative cases were divided into minor procedures (for example, placement of an intracranial pressure monitor) and major procedures (for example, craniotomy) for both battle injuries and humanitarian work. Battle injuries were defined as injuries sustained by soldiers while in the line of duty or injuries to Afghan civilians from weapons of war. Humanitarian work consisted of providing medical care to Afghans.

Results

Six neurosurgeons covering a 24-month period performed 115 minor procedures and 210 major surgical procedures cases. Operations for battlefield injuries included 106 craniotomies, 25 spine surgeries, and 18 miscellaneous surgeries. Humanitarian work included 32 craniotomies (23 for trauma, 3 for tumor, 6 for other reasons, such as cyst fenestration), 27 spine surgeries (12 for degenerative conditions, 9 for trauma, 4 for myelomeningocele closure, and 2 for the treatment of infection), and 2 miscellaneous surgeries.

Conclusions

Military neurosurgeons have provided surgical care at rates of 71% (149/210) for battlefield injuries and 29% (61/210) for humanitarian work. Of the operations for battle trauma, 50% (106/210) were cranial and 11% (25/210) spinal surgeries. Fifteen percent (32/210) and 13% (27/210) of operations were for humanitarian cranial and spine procedures, respectively. Overall, military neurosurgeons in Afghanistan are performing life-saving cranial and spine stabilization procedures for battlefield trauma and acting as general neurosurgeons for the Afghan community.

Direct gene therapy for bone regeneration: gene delivery, animal models, and outcome measures

While various problems with bone healing remain, the greatest clinical change is the absence of an effective approach to manage large segmental defects in limbs and craniofacial bones caused by trauma or cancer. Thus, nontraditional forms of medicine, such as gene therapy, have been investigated as a potential solution. The use of osteogenic genes has shown great potential in bone regeneration and fracture healing. Several methods for gene delivery to the fracture site have been described. The majority of them include a cellular component as the carrying vector, an approach known as cell-mediated gene therapy. Yet, the complexity involved with cell isolation and culture emphasizes the advantages of direct gene delivery as an alternative strategy. Here we review the various approaches of direct gene delivery for bone repair, the choice of animal models, and the various outcome measures required to evaluate the efficiency and safety of each technique. Special emphasis is given to noninvasive, quantitative, in vivo monitoring of gene expression and biodistribution in live animals. Research efforts should aim at inducing a transient, localized osteogenic gene expression within a fracture site to generate an effective therapeutic approach that would eventually lead to clinical use.

Soft tissue management of war wounds to the foot and ankle

This article details the experiences of United States military reconstructive surgeons in the soft tissue management of war wounds of the foot and ankle resulting from the conflicts in Iraq and Afghanistan. War wounds from this conflict are commonly caused by blast and fragmentation, and are characteristically extensive, heterogeneous, and severe. Multiple serial débridement episodes are routinely necessary because of deterioration of the wounds over time, which is in contrast to civilian trauma wherein fewer débridement episodes are generally required. Wound therapy adjuncts, such as subatmospheric wound dressing and synthetic dermal replacement, have been used extensively with favorable results. Pedicled flaps, such as the distally based sural neurofasciocutaneous flap, are reliable, and avoid the risks and technical demands associated with microsurgery. Free tissue transfer, such as the anterolateral thigh flap, the latissimus dorsi muscle flap, and the rectus abdominis muscle flap, are powerful reconstructive tools, and have been extensively used in the reconstruction of war wounds of the foot and ankle.

Strategies for managing massive defects of the foot in high-energy combat injuries of the lower extremity

Blast-related lower extremity trauma presents many challenges in its management that are not frequently experienced in high-energy civilian trauma. Because many of the blasts experienced in the current conflicts are ground based, the foot and ankle have sustained considerable severity and extent of injury because of the proximity of the blast. The high functional demands required of active service members create several reconstructive challenges. The authors' experience in the current conflicts has shown a similar trend, with the magnitude of soft tissue injury usually dictating whether or not salvage may be possible. Several reconstructive options for bone defect management are outlined and discussed.

War wounds of the foot and ankle: causes, characteristics, and initial management

Foot and ankle trauma sustained in the Global War on Terror have unique causes and characteristics. At least one-quarter of all battle injuries involve the lower extremity. These severe lower extremity wounds require specialized early treatment. Ballistic mechanisms cause almost all injuries, and as such, most combat foot and ankle wounds are open in nature. Wounds are characteristically caused by blast mechanisms, but high velocity gunshot injuries are also common. The severe and polytraumatic nature of injuries sustained frequently call for damage control orthopaedics to be utilized. Cautious early treatment of irregular and highly exudative ballistic wounds with subatmospheric wound dressings may ease their early management.

Use of tourniquets and their effects on limb function in the modern combat environment

Tourniquets have been called powerful lifesaving devices by some authors, whereas others say they cause more harm than good. Given recent emergency tourniquet developments in scientific design of devices, widespread user training, modern doctrine based on evidence, and thorough fielding to users within an integrated trauma system with rapid evacuation, tourniquets have shown minor morbidity and major lifesaving results. Trauma systems with poorly designed devices, inadequate user training, no tourniquet doctrine, or slow casualty evacuation, however, have repeatedly shown severe morbidity and mortality. Tourniquets may save lives if the right device is used in the right way at the right time for the right patient.

Prevention and treatment of infected foot and ankle wounds sustained in the combat environment

Combat injuries to the foot and ankle are challenging to treat due to frequent high-energy mechanisms, environmental contamination, and soft tissue and bony damage. Prevention and treatment of infections in injuries to the foot and ankle are critical to achieving the goals of tissue healing and restoration of function. The guidelines for treatment of these foot and ankle injuries are similar to those in place for civilians; however, allowances must be made for the realities of combat including an often austere environment, the need for evacuation, and limitations on resources available for treatment.

Compartment syndrome and lower-limb fasciotomies in the combat environment

Prophylactic and therapeutic treatment of leg compartment syndrome with decompression by double-incision fasciotomy prevents progression of soft-tissue injury in high-energy trauma. This treatment is the standard of care in civilian trauma and combat settings. More controversial is the use of either single- or dual-incision fasciotomy of the foot for prophylactic treatment of foot compartment syndrome. Fasciotomy must be performed in the face of major trauma to the foot with severe swelling and unremitting pain. The role for prophylactic fasciotomy of the foot is unclear and should be considered on a case by case basis. The surgeon must maintain a high degree of vigilance for the development of compartment syndrome in the combat casualty.

Early management of ballistic hand trauma

Complex hand wounds are an unfortunate consequence of conflict. Increased battlefield survival rates have resulted in an evolving range of ballistic hand trauma encountered by deployed surgical teams, requiring increased knowledge and understanding of these injuries. In the civilian setting, the combined threats of gun crime and acts of terrorism warrant appreciation for such injury among all surgeons. Surgeons often have to relearn the management of ballistic hand trauma and other aspects of war surgery under difficult circumstances because the experiences of their predecessors may be forgotten. Current evidence regarding these injuries is scarce. Ballistic hand trauma is rarely isolated. The demand on surgical resources from combat injury is significant, and it is imperative that a phased strategy be followed in this setting. Minimal, accurate débridement and decompression with early stability are crucial. Delayed primary closure and an awareness of future reconstructive options are fundamental.

Inflammatory biomarkers in combat wound healing

BACKGROUND

Modern war ballistics and blast injuries inflict devastating extremity injuries, violating soft tissue, bone, and neurovascular structures. Despite advances in complex wound management, appropriate timing of war wound closure remains subjective. In addition, the pathophysiology of acute wound failure is poorly defined.

METHODS

Patients with penetrating extremity wounds sustained during combat were prospectively studied and followed for 30 days after definitive wound closure. The primary outcome was wound healing. Wound dehiscence was defined as spontaneous partial or complete wound disruption after closure. Serum, wound effluent, and wound bed tissue biopsy were collected at each surgical wound debridement. Serum and wound effluent were analyzed with a multiplex array of 22 cytokines and chemokines, and wound tissue for corresponding gene transcript expression.

RESULTS

Fifty-two penetrating extremity war wounds in 33 male patients were investigated. Nine (17%) wounds dehisced. Concomitant vascular injury, increased wound size, and higher injury severity score correlated with wound dehiscence. Both serum and wound effluent cytokine and chemokine protein profiles were statistically associated with healing outcome at various time points. Wound biopsy gene transcript expression demonstrated increased tissue inflammation associated with wound failure. Multiple protein and gene transcript biomarkers predictive of wound healing were identified.

CONCLUSIONS

The cytokine and chemokine protein and gene transcript expression patterns demonstrate a condition of inflammatory dysregulation associated with war wound failure. A molecular biomarker panel may predict combat wound healing outcome and warrants prospective validation.

Fractures of the thoracolumbar spine sustained by soldiers in vehicles attacked by improvised explosive devices

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To analyze the types of orthopedic spine fractures sustained by North Atlantic Treaty Organization soldiers when vehicles are attacked by improvised explosive devices (IEDs), with specific focus on the flexion-distraction type thoracolumbar fracture (Chance fracture).

SUMMARY OF BACKGROUND DATA

Operation Enduring Freedom is the North Atlantic Treaty Organization's effort in Afghanistan. IED attacks on armored vehicles are common and account for high proportion of soldiers' deaths and injuries.

METHODS

Retrospective record review was accomplished on soldiers admitted to a military hospital with orthopedic spine fractures after IED attacks on vehicles from January 1, 2008 to May 15, 2008. Thoracolumbar fractures were classified using the McAfee classification system.

RESULTS

Twelve male patients with 16 thoracolumbar fractures were identified (3 patients with multiple fractures). The 16 thoracolumbar fractures included 6 flexion-distraction fractures in 5 patients (38%, 6/16: two T12, two L1, one L3, and one L4), 7 compression fractures in 5 patients (44%, 5/16; one T7, one T8, two L1, one L2, one L3, and one L4), and 3 burst fractures (19%, 3/16; two L1 and one L2).

CONCLUSION

The incidence of flexion-distraction thoracolumbar (Chance) fractures has been reported to be between 1.0% and 2.5% in most spine fracture series. In this small study, Chance fractures represented 38% of all tho-racolumbar fractures sustained after IED attack on armored vehicles. The blast pattern associated with IED explosion may be responsible for the high rate of these injuries in vehicle occupants.

Efficacy of colistin-impregnated beads to prevent multidrug-resistant A. baumannii implant-associated osteomyelitis

Osteomyelitis (OM) from multidrug-resistant (MDR) Acinetobacter has emerged in >30% of combat-related injuries in Iraq and Afghanistan. While most of these strains are sensitive to colistin, the drug is not available in bone void fillers for local high-dose delivery. To address this, we developed a mouse model with MDR strains isolated from wounded military personnel. In contrast to S. aureus OM, which is osteolytic and characterized by biofilm in necrotic bone, A. baumannii OM results in blastic lesions that do not contain apparent biofilm. We also found that mice mount a specific IgG response against three proteins (40, 47, and 56 kDa) regardless of the strain used, suggesting that these may be immuno-dominant antigens. PCR for the A. baumannii-specific parC gene confirmed a 100% infection rate with 75% of the MDR strains, and in vitro testing confirmed that all strains were sensitive to colistin. We also developed a real-time quantitative PCR (RTQ-PCR) assay that could detect as few as 10 copies of parC in a sample. To demonstrate the efficacy of colistin prophylaxis in this model, mice were treated with either parenteral colistin (0.2 mg colistinmethate i.m. for 7 days), local colistin (PMMA bead impregnated with 1.0 mg colistin sulfate), or an unloaded PMMA bead control. While the parenteral colistin failed to demonstrate any significant effects versus the placebo, the colistin PMMA bead significantly reduced the infection rate such that only 29.2% of the mice had detectable levels of parC at 19 days (p < 0.05 vs. i.m. colistin and placebo).

Treatment of war wounds: a historical review

The treatment of war wounds is an ancient art, constantly refined to reflect improvements in weapons technology, transportation, antiseptic practices, and surgical techniques. Throughout most of the history of warfare, more soldiers died from disease than combat wounds, and misconceptions regarding the best timing and mode of treatment for injuries often resulted in more harm than good. Since the 19th century, mortality from war wounds steadily decreased as surgeons on all sides of conflicts developed systems for rapidly moving the wounded from the battlefield to frontline hospitals where surgical care is delivered. We review the most important trends in US and Western military trauma management over two centuries, including the shift from primary to delayed closure in wound management, refinement of amputation techniques, advances in evacuation philosophy and technology, the development of antiseptic practices, and the use of antibiotics. We also discuss how the lessons of history are reflected in contemporary US practices in Iraq and Afghanistan.

Battlefield extremity injuries in Operation Iraqi Freedom

OBJECTIVE

Extremity injuries account for the majority of wounds incurred during US armed conflicts. Information regarding the severity and short-term outcomes of patients with extremity wounds, however, is limited. The aim of the present study was to describe patients with battlefield extremity injuries in Operation Iraqi Freedom (OIF) and to compare characteristics of extremity injury patients with other combat wounded.

PATIENTS AND METHODS

Data were obtained from the United States Navy-Marine Corps Combat Trauma Registry (CTR) for patients who received treatment for combat wounds at Navy-Marine Corps facilities in Iraq between September 2004 and February 2005. Battlefield extremity injuries were classified according to type, location, and severity; patient demographic, injury-specific, and short-term outcome data were analysed. Upper and lower extremity injuries were also compared.

RESULTS

A total of 935 combat wounded patients were identified; 665 (71%) sustained extremity injury. Overall, multiple wounding was common (an average of 3 wounds per patient), though more prevalent amongst patients with extremity injury than those with other injury (75% vs. 56%, P<.001). Amongst the 665 extremity injury patients, 261 (39%) sustained injury to the upper extremities, 223 (34%) to the lower extremities, and 181 (27%) to both the upper and lower extremities. Though the total number of patients with upper extremity injury was higher than lower extremity injury, the total number of extremity wounds (n=1654) was evenly distributed amongst the upper and lower extremities (827 and 827 wounds, respectively). Further, lower extremity injuries were more likely than the upper extremity injuries to be coded as serious to fatal (AIS>2, P<.001).

CONCLUSIONS

Extremity injuries continue to account for the majority of combat wounds. Compared with other conflicts, OIF has seen increased prevalence of patients with upper extremity injuries. Wounds to the lower extremities, however, are more serious. Further research on the risks and outcomes associated with extremity injury is necessary to enhance the planning and delivery of combat casualty medical care.

Perioperative blood transfusion in combat casualties: a pilot study

BACKGROUND

In recent studies, blood transfusion has been shown to increase the rate of wound healing disturbances in orthopedic patients. Furthermore, our group has determined a correlation between delayed wound healing and elevations in inflammatory mediators in combat casualties. Therefore, we sought to determine the effect of blood transfusion on wound healing and inflammatory mediator release in combat casualties.

METHODS

Prospective data were collected on 20 severely injured combat casualties sustaining extremity wounds. Patients were admitted to the National Naval Medical Center during a 13-month period from January 2007 to January 2008. Data variables included age, gender, Glasgow coma score (GCS), mechanism of injury, and transfusion history. Injury severity was assessed using the Injury Severity Score (ISS). Serum was collected initially and before each surgical wound debridement and analyzed using a panel of 21 cytokines and chemokines. The association between blood transfusion and wound healing, incidence of perioperative infection, intensive care unit (ICU) admission rate, and ICU and hospital length of stay was assessed. Differences were considered significant when p < 0.05.

RESULTS

The study cohort had a mean age of 22 +/- 1, a mean ISS of 15.8 +/- 2.6, and a mean GCS 13.9 +/- 0.6; all were men and suffered penetrating injuries (90% improvised explosive device [IED] and 10% gunshot wound [GSW]). The cohort was divided into two groups. Patients receiving <or=4 units of blood initially (group 1, n = 11) were compared with patients who received >4 units of blood initially (group 2, n = 9). There was no significant difference in age, ISS, GCS, or mortality between the two groups. However, group 2 patients had significant impairment in wound healing rate (54% vs. 9%, p < 0.05), higher ICU admission rate (78% vs. 9%, p < 0.01), perioperative infection rate (89% vs. 27%, p < 0.01), and a longer hospital length of stay (49.9 +/- 12.8 vs. 23.8 +/- 2.9, p < 0.05) compared with group 1 patients. In addition, there was a significant correlation between the initial mean serum cytokine/chemokine level of interleukin (IL)-10, IL-8, interferon inducible protein (IP)-10, IL-6, and IL-12p40 and the number of units of blood transfused (p < 0.05).

CONCLUSION

Allogeneic blood transfusions in combat casualties were associated with impaired wound healing, increased perioperative infection rate, and resource utilization. In addition, the extent of blood transfusion was associated with significant differences in inflammatory chemokine and cytokine release.

The effect of a hypobaric, hypoxic environment on acute skeletal muscle edema after ischemia-reperfusion injury in rats

BACKGROUND

Clinicians have postulated that decreased atmospheric pressure during air evacuation exacerbates muscle edema and necrosis in injured limbs. The present study investigated whether the mild hypobaric, hypoxic conditions of simulated flight during muscle reperfusion worsened muscle edema and muscle injury in an established animal model.

METHODS

Twenty male Sprague-Dawley rats underwent tourniquet-induced hind limb ischemia for 2h. After removal of the tourniquet, rats were divided into two groups (n=10/group), and exposed to either (1) hypobaric, hypoxic conditions (HB) of 522 mm Hg (simulating 10,000 feet, the upper limit of normal aircraft cabin pressure), or (2) normobaric, normoxic conditions (NB) of 760 mm Hg (sea level), for 6h. Muscle wet weight, muscle dry:wet weight ratios, viability, and routine histology were measured on the gastrocnemius and tibialis anterior muscles. Blood samples were analyzed for percentage hematocrit, leukocyte count, and coagulation status.

RESULTS

Ischemia resulted in significant edema in both groups (P<0.05). Normobaric normoxia caused greater edema in the gastrocnemius compared with hypobaric hypoxia; the tibialis anterior was not significantly different between groups. The decrease in body weight for NB and HB was 3.4+/-1.4 and 10.7+/-1.2g, respectively (P<0.05). Hematocrit was 44.7+/-0.5 and 42.6+/-0.6 (P<0.05).

CONCLUSIONS

The hypobaric, hypoxic conditions of simulated medical air evacuation were not associated with increased muscle edema following 2h of ischemic injury. This suggests that other factors, such as resuscitation, may be the cause of muscle edema in flight-evacuated patients.

Impact of military conflict on a civilian receiving hospital in a war zone

OBJECTIVE

To study the impact of war on the workload/finances of a community hospital adjacent to the front.

SUMMARY BACKGROUND DATA

Community hospitals located nearby/within military conflict zones treat trauma casualties while providing routine surgical services to the community.

METHODS

Observational study conducted in Ziv hospital (1 of 3 designated receiving hospitals during the second Lebanon War (12/7/2006-14/8/2006). Data were documented in real-time and retrieved retrospectively from computerized databases.

RESULTS

Ziv treated 1509 military/civilian casualties. Seven percent were at least moderately injured. 27.5% of the casualties required admission, preferentially to surgical wards. Critical mortality rate was 7%. There were 48 secondary transfers, half from the department of emergency medicine (ED) and half after in-hospital stabilization/emergency surgery including 7 to free intensive care (ICU) beds to accommodate expected casualties. The General Surgery department (GSD) performed 81 operating room (OR) procedures, including explorations/debridements for casualties (n = 24, 0-3 per-day), laparotomies for acute abdomen (n = 33) and cancer surgery (n = 11).Compared with previous/later years, there were 23% more trauma casualties presenting to the ED and an increased OR workload for Orthopedic surgery. Decreases occurred in the number of elective and emergency admissions (10%), obstetric deliveries (28%), OR procedures (33%), GSD OR procedures (44%), hospital revenues (up to 43%), yearly hospitalization days (7%), number of hospitalized patients, bed occupancy rates, and visits to outpatient clinics (all 5%).

CONCLUSIONS

Treatment of civilian/military casualties resulted in reorganization of hospital operations with significantly decreased accrued revenue. The bulk of the GSD workload shifts from the OR to the ED/wards while Orthopedic procedures and ICU beds become bottlenecks to patient flow during war.

Resource utilization and disability outcome assessment of combat casualties from Operation Iraqi Freedom and Operation Enduring Freedom

OBJECTIVES

Injuries are common during combat operations. The high costs of extremity injuries both in resource utilization and disability are well known in the civilian sector. We hypothesized that, similarly, combat-related extremity injuries, when compared with other injures from the current conflicts in Iraq and Afghanistan, require the largest percentage of medical resources, account for the greatest number of disabled soldiers, and have greater costs of disability benefits.

DESIGN

Descriptive epidemiologic study and cost analysis.

METHODS

The Department of Defense Medical Metrics (M2) database was queried for the hospital admissions and billing data of a previously published cohort of soldiers injured in Iraq and Afghanistan between October 2001 and January 2005 and identified from the Joint Theater Trauma Registry. The US Army Physical Disability Administration database was also queried for Physical Evaluation Board outcomes for these soldiers, allowing calculation of disability benefit cost. Primary body region injured was assigned using billing records that gave a primary diagnosis International Classification of Diseases Ninth Edition code, which was corroborated with Joint Theater Trauma Registry injury mechanisms and descriptions for accuracy.

RESULTS

A total of 1333 soldiers had complete admission data and were included from 1566 battle injuries not returned to duty of 3102 total casualties. Extremity-injured patients had the longest average inpatient stay at 10.7 days, accounting for 65% of the $65.3-million total inpatient resource utilization, 64% of the 464 patients found "unfit for duty," and 64% of the $170-million total projected disability benefit costs. Extrapolation of data yields total disability costs for this conflict, approaching $2 billion.

CONCLUSIONS

Combat-related extremity injuries require the greatest utilization of resources for inpatient treatment in the initial postinjury period, cause the greatest number of disabled soldiers, and have the greatest projected disability benefit costs. This study highlights the need for continued or increased funding and support for military orthopaedic surgeons and extremity trauma research efforts.

From the battlefront: peripheral nerve surgery in modern day warfare

Warfare historically causes a large number of peripheral nerve injuries. During the current global war on terror, an increased use of advanced regional anesthesia techniques appears to have significantly reduced pain syndromes that have been previously reported with missile-induced nerve injuries. Additionally, a new program has been established to develop advanced prosthetic devises that can interface with neural tissue to obtain direct neural control. As this technology matures, the functional restoration gained from these new generation prosthetic devices may exceed that which can be obtained by standard nerve repair techniques.

Augmented subatmospheric wound dressings (SAWDA): technique tip

Level of Evidence: V, Expert Opinion

New advances in musculoskeletal pain

Non-malignant musculoskeletal pain is the most common clinical symptom that causes patients to seek medical attention and is a major cause of disability in the world. Musculoskeletal pain can arise from a variety of common conditions including osteoarthritis, rheumatoid arthritis, osteoporosis, surgery, low back pain and bone fracture. A major problem in designing new therapies to treat musculoskeletal pain is that the underlying mechanisms driving musculoskeletal pain are not well understood. This lack of knowledge is largely due to the scarcity of animal models that closely mirror the human condition which would allow the development of a mechanistic understanding and novel therapies to treat this pain. To begin to develop a mechanism-based understanding of the factors involved in generating musculoskeletal pain, in this review we present recent advances in preclinical models of osteoarthritis, post-surgical pain and bone fracture pain. The models discussed appear to offer an attractive platform for understanding the factors that drive this pain and the preclinical screening of novel therapies to treat musculoskeletal pain. Developing both an understanding of the mechanisms that drive persistent musculoskeletal pain and novel mechanism-based therapies to treat these unique pain states would address a major unmet clinical need and have significant clinical, economic and societal benefits.

Short-term outcomes of severe open wartime tibial fractures treated with ring external fixation

BACKGROUND

The treatment of complex open tibial fractures sustained in combat remains controversial. This study investigated the short-term outcomes of type-III tibial shaft fractures treated at our institution with ring external fixation.

METHODS

A retrospective review identified sixty-seven type-III tibial shaft fractures in sixty-five consecutive patients treated between April 2004 and January 2007. Of these, forty-five tibiae in forty-three patients received fracture fixation with ring external fixation. The cases of thirty-six patients, who received treatment for thirty-eight tibial shaft fractures to completion with a standardized protocol, were reviewed.

RESULTS

A blast mechanism accounted for thirty-five injuries, and three injuries were from high-velocity gunshot wounds. There were twenty-one type-IIIA, thirteen type-IIIB, and four type-IIIC fractures. Rotational or free soft-tissue flap coverage was performed on fifteen patients. Eighteen patients received planned delayed bone-grafting, and nine had only bone morphogenetic protein placed at the fracture site at the time of final wound closure. All fractures healed with <5 degrees of malalignment. One patient underwent elective delayed amputation. The average time to union with frame removal was 221 days (range, 102 to 339 days).

CONCLUSIONS

Treatment of severe open wartime tibial fractures with a protocol-driven approach to wound management and placement of ring external fixation can result in a low rate of complications and a relatively high rate of fracture union. Most complications can be successfully managed without frame removal.

Infectious disease complications of combat-related injuries

BACKGROUND

: Strategies currently used to prevent morbidity and mortality associated with combat-related injuries include better training of frontline medical personnel, improved personal protective equipment, and deployment of fast-forward surgical assets with state-of-the-art equipment. These strategies allow patients to survive near-catastrophic injuries, placing a greater emphasis on the medical infrastructure to mitigate short- and long-term complications associated with these injuries.

DISCUSSION

: Wounds have certain characteristics that promote the development of infections: the presence of devitalized tissue, foreign bodies, clots, fluid collections, and contamination of wounds with bacteria from the casualty's skin, the environment, and the hospital. All of these factors culminate in placing the casualty at risk of developing an infection.

SUMMARY

: This article reviews the lessons learned from combat-related wound infections throughout history and in the current conflicts in Iraq and Afghanistan. Many of the management strategies used to prevent infections of combat-related injuries are applicable to the management of civilian trauma, whether associated with small arms fire or related to natural disasters such as earthquakes or tornadoes.

Prehospital tourniquet use in Operation Iraqi Freedom: effect on hemorrhage control and outcomes

BACKGROUND

Up to 9% of casualties killed in action during the Vietnam War died from exsanguination from extremity injuries. Retrospective reviews of prehospital tourniquet use in World War II and by the Israeli Defense Forces revealed improvements in extremity hemorrhage control and very few adverse limb outcomes when tourniquet times are less than 6 hours.

HYPOTHESIS

We hypothesized that prehospital tourniquet use decreased hemorrhage from extremity injuries and saved lives, and was not associated with a substantial increase in adverse limb outcomes.

METHODS

This was an institutional review board-approved, retrospective review of the 31st combat support hospital for 1 year during Operation Iraqi Freedom. Inclusion criteria were any patient with a traumatic amputation, major extremity vascular injury, or documented prehospital tourniquet.

RESULTS

Among 3,444 total admissions, 165 patients met inclusion criteria. Sixty-seven patients had prehospital tourniquets (TK); 98 patients had severe extremity injuries but no prehospital tourniquet (No TK). Extremity Acute Injury Scores were the same (3.5 TK vs. 3.4 No TK) in both groups. Differences (p < 0.05) were noted in the numbers of patients with arm injuries (16.2% TK vs. 30.6% No TK), injuries requiring vascular reconstruction (29.9% TK vs. 52.5% No TK), traumatic amputations (41.8% TK vs. 26.3% No TK), and in those patients with adequate bleeding control on arrival (83% TK vs. 60% No TK). Secondary amputation rates (4 (6.0%) TK vs. 9 (9.1%) No TK); and mortality (3 (4.4%) TK vs. 4 (4.1%) No TK) did not differ. Tourniquet use was not deemed responsible for subsequent amputation in severely mangled extremities. Analysis revealed that four of seven deaths were potentially preventable with functional prehospital tourniquet placement.

CONCLUSIONS

Prehospital tourniquet use was associated with improved hemorrhage control, particularly in the worse injured (Injury Severity Score >15) subset of patients. Fifty-seven percent of the deaths might have been prevented by earlier tourniquet use. There were no early adverse outcomes related to tourniquet use.

Osteomyelitis in military personnel wounded in Iraq and Afghanistan

BACKGROUND

Orthopedic injuries occurring in Operations Iraqi Freedom and Enduring Freedom (OIF/OEF) are complicated by infections with multidrug resistant bacteria. We describe demographics and microbiology of OIF/OEF casualties with primary and recurrent osteomyelitis.

METHODS

A retrospective cohort study was performed of OIF/OEF casualties admitted to our facility from February 1, 2003 to August 31, 2006. Electronic records were queried for demographic information, bacteria recovered, antibiotic therapies and duration, site of osteomyelitis, orthopedic devices, and outcomes.

RESULTS

There were 110 patients with 139 hospitalizations for osteomyelitis; 94 involved lower extremities, 43 involved upper extremities, and 2 involved the axial skeleton. One hundred three admissions were initial episodes whereas 36 admissions were recurrences. The median age was 27 years; 95% were men. Duration of follow-up ranged from 2 weeks to 36 months. Those patients with orthopedic devices had recurrent infections more frequently (26 vs. 5%, p < 0.01). Bacteria, antibiotics, or infection site were not predictive of recurrence. Acinetobacter spp. (70 vs. 5%, p < 0.01), Klebsiella pneumoniae (18 vs. 5%, p = 0.04), and Pseudomonas aeruginosa (24 vs. 5%, p < 0.01) were more likely to be recovered during original episodes than during recurrences. Gram-positive organisms were more likely during recurrences; Staphylococcus aureus (13 vs. 53%, p < 0.01); methicillin susceptible S. aureus (5 vs. 22%, p < 0.01), methicillin resistant S. aureus (8 vs. 31%, p < 0.01).

CONCLUSIONS

The microbiology of osteomyelitis in veterans of OIF/OEF differs substantially depending upon whether the infection is new or recurrent. Gram-negative pathogens predominate early, being replaced with staphylococci after treatment, despite nearly universal use of gram- positive therapy.

Epidemiology of infections associated with combat-related injuries in Iraq and Afghanistan

Enhanced medical training of front line medical personnel, personal protective equipment, and the presence of far forward surgical assets have improved the survival of casualties in the current wars in Iraq and Afghanistan. As such, casualties are at higher risk of infectious complications of their injuries including sepsis, which was a noted killer of casualties in previous wars. During the current conflicts, military personnel who develop combat-related injuries are at substantial risk of developing infections with multidrug resistant bacteria. Herein, we describe the bacteriology of combat-related injuries in Operation Iraqi Freedom and Operation Enduring Freedom that develop infections with particular attention to injuries of the extremities, central nervous system, abdomen and thorax, head and neck, and burns. In addition, the likely sources of combat-related injuries with multidrug resistant bacteria infections are explored.

Prevention and management of infections associated with combat-related extremity injuries

Orthopedic injuries suffered by casualties during combat constitute approximately 65% of the total percentage of injuries and are evenly distributed between upper and lower extremities. The high-energy explosive injuries, environmental contamination, varying evacuation procedures, and progressive levels of medical care make managing combat-related injuries challenging. The goals of orthopedic injury management are to prevent infection, promote fracture healing, and restore function. It appears that 2% to 15% of combat-related extremity injuries develop osteomyelitis, although lower extremity injuries are at higher risk of infections than upper extremity. Management strategies of combat-related injuries primarily focus on early surgical debridement and stabilization, antibiotic administration, and delayed primary closure. Herein, we provide evidence-based recommendations from military and civilian data to the management of combat-related injuries of the extremity. Areas of emphasis include the utility of bacterial cultures, antimicrobial therapy, irrigation fluids and techniques, timing of surgical care, fixation, antibiotic impregnated beads, wound closure, and wound coverage with negative pressure wound therapy. Most of the recommendations are not supported by randomized controlled trials or adequate cohorts studies in a military population and further efforts are needed to answer best treatment strategies.

Guidelines for the prevention of infection after combat-related injuries

Management of combat-related trauma is derived from skills and data collected in past conflicts and civilian trauma, and from information and experience obtained during ongoing conflicts. The best methods to prevent infections associated with injuries observed in military combat are not fully established. Current methods to prevent infections in these types of injuries are derived primarily from controlled trials of elective surgery and civilian trauma as well as retrospective studies of civilian and military trauma interventions. The following guidelines integrate available evidence and expert opinion, from within and outside of the US military medical community, to provide guidance to US military health care providers (deployed and in permanent medical treatment facilities) in the diagnosis, treatment, and prevention of infections in those individuals wounded in combat. These guidelines may be applicable to noncombat traumatic injuries under certain circumstances. Early wound cleansing and surgical debridement, antibiotics, bony stabilization, and maintenance of infection control measures are the essential components to diminish or prevent these infections. Future research should be directed at ideal treatment strategies for prevention of combat-related injury infections, including investigation of unique infection control techniques, more rapid diagnostic strategies for infection, and better defining the role of antimicrobial agents, including the appropriate spectrum of activity and duration.

Extremity War Injuries: Development of Clinical Treatment Principles

The AAOS/OTA Extremity War Injuries: Development of Clinical Treatment Principles symposium, held in January 2007, was a follow-up to the first Extremity War Injuries symposium held a year earlier. Discussion focused on four specific areas: prehospital management of extremity wounds, initial débridement, early stabilization, and postoperative wound management during air evacuation. Liberal emergency use of field tourniquets likely is contributing to lower overall mortality and is associated with very low rates of complications. Additional tools for extremity hemorrhage control, such as chitosan-based patches and granular zeolite hemostat, were postulated to be effective. Consensus opinion was that necrotic, devitalized, and contaminated tissue must be removed although objective assessment of completeness of initial débridement is difficult. Definitive open reduction and internal fixation for US and Coalition forces in the theater of operations should be limited to fracture patterns associated with significant perceived risk of delay in treatment. Finally, primary skin closure should be avoided in theater. In addition, because of the time and complications involved in transporting patients to level 4 care facilities, surgeons should consider release of compartments prior to patient transport whenever significant perceived potential for compartment syndrome is present.