Robert Burks

Combat wounds in Iraq and Afghanistan from 2005 to 2009.

BACKGROUND There have been no large cohort studies examining the wounding patterns and injury mechanisms in Iraq and Afghanistan from 2005 to 2009. This investigation sought to characterize the incidence and epidemiology of combat-related injuries for this period. METHODS Using the Joint Theater Trauma Registry, a detailed description of the combat casualty care statistics, distribution of wounds, and injury mechanisms sustained by all US service members for wounds (DRG International Classification of Diseases—9th Rev. codes 800–960) during the Iraq and Afghanistan Wars from 2005 to 2009 was performed. RESULTS Among the 1,992,232 military service members who were deployed, there were 29,624 distinct combat wounds in 7,877 combat casualties. The mean age of the combat casualty cohort was 26.0 years old. The combat casualties were predominantly male (98·8%), Army (77·5%), and junior enlisted (59·0%). The distribution of combat wounds was as follows: head/neck, 28·1%; thorax, 9·9%; abdomen, 10·1%; and extremities, 51·9%. Explosive injury mechanisms accounted for 74·4% of all combat casualties, which was significantly higher than those caused by gunshot wounds (19·9%) (p < 0.0001). From 2005 to 2007, explosive mechanisms of injury were significantly more common in Iraq than in Afghanistan (p < 0.001). The percentage of explosive mechanisms increased significantly in Afghanistan between the years 2007 (59·5%) and 2008 (73·6%) (p < 0.0003). CONCLUSION The wounding patterns observed in Iraq and Afghanistan from 2005 to 2009 differ from previous conflicts. Explosive mechanisms accounted for 74·4% of combat casualties, which is a higher percentage than in previous US conflicts. A progressive increase in the use of explosive mechanisms in Afghanistan, eventually equaling that in Iraq, was observed during the study period. (J Trauma Acute Care Surg. 2012;73: 3–12. Copyright

Disease and nonbattle injuries sustained by a U.S. Army Brigade Combat Team during Operation Iraqi Freedom.

BACKGROUND A longitudinal cohort analysis of disease nonbattle injuries (DNBI) sustained by a large combat-deployed maneuver unit has not been performed. METHODS A descriptive analysis was undertaken to evaluate for DNBI casualty care statistics incurred by a U.S. Army Brigade Combat Team (BCT) during a counterinsurgency campaign of Operation Iraqi Freedom. RESULTS Of the 4,122 soldiers deployed, there were 1,324 DNBI with 5 (0.38%) deaths, 208 (15.7%) medical evacuations (MEDEVAC), and 1,111 (83.9%) returned to duty. The DNBI casualty rate for the BCT was 257.0/1,000 soldier combat-years. Females, compared with males, had a significantly increased incidence rate ratio for becoming a DNBI casualty 1.67 (95% CI 1.37, 2.04). Of 47 female soldiers receiving MEDEVAC 35 (74%) were for pregnancy-related issues. Musculoskeletal injuries (50.4%) and psychiatric disorders (23.3%) were the most common body systems involved with DNBI casualties. Among the BCT cohort the psychiatric DNBI casualty rate and suicide rate were 59.8 and 0.58 per 1,000 soldier combat-years. The BCT cohort incidence rates for common musculoskeletal injuries per 1,000 combat-years were as follows: ankle sprain 15.3, anterior cruciate ligament rupture 3.3 and shoulder dislocation 1.2. CONCLUSIONS Musculoskeletal injuries and psychiatric disorders accounted for 74% of the total DNBI casualties, and 43% of the DNBI casualties requiring subsequent MEDEVAC. The BCT cohort had a suicide rate nearly four times greater than previously reported, and selected musculoskeletal injury incidence rates were fivefold greater than the general population.

Incidence of Acute Traumatic Patellar Dislocation among Active-Duty United States Military Service Members

Background Although some studies have reported an increased incidence of patellar dislocations within active populations, few studies have reported incidence rates and examined risk factors for this injury. Purpose To examine the incidence of patellar dislocation injuries and the influence of demographic and occupational risk factors associated with injury among active-duty United States (US) service members between 1998 and 2007. Study Design Cohort study; Level of evidence, 3. Methods Using the Defense Medical Surveillance System, a search was performed for International Classification of Disease, 9th Revision (ICD-9) code 836.3 among all US service members on active duty during the study period. Multivariable Poisson regression analysis was used to estimate the rate of patellar dislocation per 1000 person-years at risk to injury. Incidence rates (IRs) and incidence rate ratios (IRRs) for patellar dislocation along with 95% confidence intervals (CIs) were estimated by gender, age, race, branch of military service, and rank while controlling for the other variables in the model. Results There were a total of 9299 individuals with documented patellar dislocation injuries among a population at risk of 13 443 448 person-years. The IR was 0.69 per 1000 person-years at risk. Women were 61% more likely (IRR, 1.61; 95% CI, 1.53-1.69) to sustain a patellar dislocation injury than men. Rates were highest in the youngest age group and decreased with increasing age. Service members aged <20 years were 84% more likely (IRR, 1.84; 95% CI, 1.61-2.10) to sustain a patellar dislocation injury as service members aged ≥40 years. Differences were also noted by race, service, and rank. Conclusion The incidence of patellar dislocation injuries among US service members was an order of magnitude greater than that previously reported in civilian population studies. Gender, age, race, rank, and branch of military service are important risk factors related to the incidence of patellar dislocation injuries in this population.

Incidence and Risk Factors Associated with Meniscal Injuries Among Active-Duty US Military Service Members

CONTEXT Few population-based studies have examined the incidence of meniscal injuries, and limited information is available on the influence of patients demographic and occupational factors. OBJECTIVE To examine the incidence of meniscal injuries and the influence of demographic and occupational factors among active-duty US service members between 1998 and 2006. DESIGN Cohort study. SETTING Using the International Classification of Diseases (9th revision) codes 836.0 (medial meniscus), 836.1 (lateral meniscus), and 836.2 (meniscus unspecified), we extracted injury data from the Defense Medical Surveillance System to identify all acute meniscal injuries among active-duty military personnel. PATIENTS OR OTHER PARTICIPANTS Active-duty military personnel serving in all branches of military service during the study period. MAIN OUTCOME MEASURE(S) Incidence rate (IR) per 1000 person-years at risk and crude and adjusted rates by strata for age, sex, race, rank, and service. RESULTS During the study period, 100201 acute meniscal injuries and 12115606 person-years at risk for injury were documented. The overall IR was 8.27 (95% confidence interval [CI] = 8.22, 8.32) per 1000 person-years. Main effects were noted for all demographic and occupational variables (P < .001), indicating that age, sex, race, rank, and service were associated with the incidence of meniscal injuries. Men were almost 20% more likely to experience an acute meniscal injury than were women (incidence rate ratio = 1.18, 95% CI = 1.15, 1.20). The rate of meniscal injury increased with age; those older than 40 years of age experienced injuries more than 4 times as often as those under 20 years of age (incidence rate ratio = 4.25, 95% CI=4.08,4.42). CONCLUSIONS The incidence of meniscal injury was substantially higher in this study than in previously reported studies. Male sex, increasing age, and service in the Army or Marine Corps were factors associated with meniscal injuries.

The Incidence of Low Back Pain in Active Duty United States Military Service Members

Study Design. Epidemiological study. Objective. To investigate the incidence and risk factors for developing low back pain in active duty military population to include age, sex, race, and rank, and military service. Summary of Background Data. Low back pain is among the most common musculoskeletal conditions worldwide and is estimated to affect nearly two-thirds of the US population at some point in their lives. Low back pain is a multifactorial disease and many risk factors have been implicated including age, race, sex, and marital status. Methods. A query was performed using the US Defense Medical Epidemiology Database (DMED) for the International Classification of Diseases, Ninth Revision, Clinical Modification code for low back pain (724.20). 13,754,261 person-years of data were investigated. Multivariate Poisson regression analysis was used to estimate the rate of low back pain per 1000 person-years, whereas controlling for sex, race, rank, service, age, and marital status. Results. The overall unadjusted incidence rate of low back pain was 40.5 per 1000 person-years. Women, compared with men, had a significantly increased incidence rate ratio for low back pain of 1.45. The incidence rate ratio for the 40+ age group compared with the 20 to 29 years of age group was 1.28. With junior officers as the referent category, junior- and senior-enlisted rank groups had increased incidence rate ratio for low back pain, 1.95 and 1.35, respectively. Each service, when compared with the Marines as the referent category, had a significantly increased incidence rate ratio of low back pain: Army: 2.19, Navy: 1.02, and Air Force: 1.54. Compared with single service members, significantly increased incidence rate ratio for low back pain were seen in married service members: 1.21. Conclusion. Female sex, enlisted rank groups, service in the Army, Navy, or Air Force, age greater than 40 years, and a marital status of married were all risk factors for low back pain.

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

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

Epidemiology of lateral and medial epicondylitis in a military population.

OBJECTIVE To determine the epidemiology of lateral and medial epicondylitis in the U.S. military. METHODS The Defense Medical Epidemiology Database was queried for ICD-9 codes 726.32 (lateral epicondylitis) and 726.33 (medial epicondylitis) for the years 1998-2006. Multivariate Poisson regression was used to calculate incidence rates (IR) and rate ratios (RR) among demographic groups. RESULTS The IRs for lateral and medial epicondylitis were 2.98 and 0.81 per 1000 person-years. For lateral epicondylitis, women had a higher incidence (RR = 1.22, 95% CI 1.19-1.26). In both groups, analysis by age showed higher incidence in the > or = 40-year-old group. White compared with black race was a risk factor for both lateral (RR = 1.68, 95% CI, 1.63-1.74) and medial epicondylitis (RR = 1.11, 95% CI 1.05-1.17). CONCLUSIONS Female gender was a risk factor for lateral but not medial epicondylitis. Age greater than 40 and white race were significant risk factors for both conditions.

Effects of serial anesthesia using ketamine or ketamine/medetomidine on hematology and serum biochemistry values in rhesus macaques (Macaca Mulatta)

Background  This study aimed at determining the cumulative effect of daily anesthesia, using two drug regimens, over hematological and biochemical parameters.

Incidence and epidemiology of spinal cord injury within a closed American population: the United States military (2000-2009).

Study design:Cohort studyObjectives:The objective of this study was to characterize the incidence of spinal cord injury (SCI) within the population of the United States military from 2000–2009. This investigation also sought to define potential risk factors for the development of SCI.Setting:The population of the United States military from 2000–2009.Methods:The Defense Medical Epidemiology Database was queried for the years 2000–2009 using the International Classification of Diseases, Ninth Revision, Clinical Modification codes for SCI (806.0, 806.1, 806.2, 806.3, 806.4, 806.5, 806.8, 806.9, 952.0, 952.1, 952.2, 952.8, 952.9). The raw incidence of SCI was calculated and unadjusted incidence rates were generated for the risk factors of age, sex, race, military rank and branch of service. Adjusted incidence rate ratios were subsequently determined via multivariate Poisson regression analysis that controlled for other factors in the model and identified significant independent risk factors for SCI.Results:Between 2000 and 2009, there were 5928 cases of SCI among a population at-risk of 13 813 333. The raw incidence of SCI within the population was 429 per million person-years. Male sex, white race, enlisted personnel and service in the Army, Navy or Marine Corps were found to be significant independent risk factors for SCI. The age groups 20–24, 25–29 and >40 were also found to be at significantly greater risk of developing the condition.Conclusions:This study is one of the few investigations to characterize the incidence, epidemiology and risk factors for SCI within the United States. Results presented here may represent the best-available evidence for risk factors of SCI in a large and diverse American cohort.

Incidence and risk factors for lumbar degenerative disc disease in the United States military 1999-2008.

The epidemiology of lumbar degenerative disc disease (DDD) is poorly understood, and the incidence of this disorder has not previously been characterized for a young, physically active population. This study sought to evaluate the incidence of lumbar DDD, and identify risk factors for its development, among individuals serving in the U.S. military over a 10-year period. The Defense Medical Epidemiology Database was queried for the years 1999-2008 using the International Classification of Diseases, Ninth Revision, Clinical Modification code for lumbar disc degeneration (722.52). Overall incidence was determined and multivariate Poisson regression analysis was performed to identify risk factors among demographic characteristics such as age, sex, race, military rank, and branch of service. White race, female sex, Army, Air Force, or Marine service, enlisted positions within the ranks, and age were found to be significant risk factors for the development of lumbar disc degeneration. Increased age appeared to be one of the most important risk factors, with adjusted incidence rates successively increasing for each age group under study. The incidence of lumbar DDD in this young, racially diverse, and physically active population is higher than most other degenerative conditions.