Brett D. Owens

Combat wounds in operation Iraqi Freedom and operation Enduring Freedom.

BACKGROUND There have been no large cohort reports detailing the wounding patterns and mechanisms in the current conflicts in Iraq and Afghanistan. METHODS The Joint Theater Trauma Registry was queried for all US service members receiving treatment for wounds (International Classification of Diseases-9th Rev. codes 800-960) sustained in Operation Iraqi Freedom and Operation Enduring Freedom from October 2001 through January 2005. Returned-to-duty and nonbattle injuries were excluded from final analysis. RESULTS This query resulted in 3,102 casualties, of which 31% were classified as nonbattle injuries and 18% were returned-to-duty within 72 hours. A total of 1,566 combatants sustained 6,609 combat wounds. The locations of these wounds were as follows: head (8%), eyes (6%), ears (3%), face (10%), neck (3%), thorax (6%), abdomen (11%), and extremity (54%). The proportion of head and neck wounds is higher (p < 0.0001) than the proportion experienced in World War II, Korea, and Vietnam wars (16%-21%). The proportion of thoracic wounds is a decrease (p < 0.0001) from World War II and Vietnam (13%). The proportion of gunshot wounds was 18%, whereas the proportion sustained from explosions was 78%. CONCLUSIONS The wounding patterns currently seen in Iraq and Afghanistan resemble the patterns from previous conflicts, with some notable exceptions: a greater proportion of head and neck wounds, and a lower proportion of thoracic wounds. An explosive mechanism accounted for 78% of injuries, which is the highest proportion seen in any large-scale conflict.

Characterization of Extremity Wounds in Operation Iraqi Freedom and Operation Enduring Freedom

Objectives: Extremity wounds and fractures traditionally comprise the majority of traumatic injuries in US armed conflicts. Little has been published regarding the extremity wounding patterns and fracture distribution in the current conflicts in Iraq and Afghanistan. The intent of this study was to describe the distribution of extremity fractures during this current conflict. Design: Descriptive epidemiologic study. Methods: The Joint Theater Trauma Registry was queried for all US service members receiving treatment for wounds (ICD-9 codes 800-960) sustained in Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) from October 2001 through January 2005. Returned-to-duty and nonbattle injuries were excluded. Wounds were classified according to region and type. Extremity wounds were analyzed in detail and compared to published results from previous conflicts. Results: A total of 1281 soldiers sustained 3575 extremity combat wounds. Fifty-three percent of these were penetrating soft-tissue wounds and 26% were fractures. Of the 915 fractures, 758 (82%) were open fractures. The 915 fractures were evenly distributed between the upper (461, 50%) and lower extremities (454, 50%). The most common fracture in the upper extremity was in the hand (36%) and in the lower extremity was the tibia and fibula (48%). Explosive munitions accounted for 75% of the mechanisms of injury. Conclusions: The burden of wounds sustained in OIF/OEF is extremity injuries, specifically soft-tissue wounds and fractures. These results are similar to the reported casualties from previous wars.

The Epidemiology of Ankle Sprains in the United States

BACKGROUND Ankle sprain has been studied in athletic cohorts, but little is known of its epidemiology in the general population. A longitudinal, prospective epidemiological database was used to determine the incidence and demographic risk factors for ankle sprains presenting to emergency departments in the United States. It was our hypothesis that ankle sprain is influenced by sex, race, age, and involvement in athletics. METHODS The National Electronic Injury Surveillance System (NEISS) was queried for all ankle sprain injuries presenting to emergency departments between 2002 and 2006. Incidence rate ratios were then calculated with respect to age, sex, and race. RESULTS During the study period, an estimated 3,140,132 ankle sprains occurred among an at-risk population of 1,461,379,599 person-years for an incidence rate of 2.15 per 1000 person-years in the United States. The peak incidence of ankle sprain occurred between fifteen and nineteen years of age (7.2 per 1000 person-years). Males, compared with females, did not demonstrate an overall increased incidence rate ratio for ankle sprain (incidence rate ratio, 1.04; 95% confidence interval, 1.00 to 1.09). However, males between fifteen and twenty-four years old had a substantially higher incidence of ankle sprain than their female counterparts (incidence rate ratio, 1.53; 95% confidence interval, 1.41 to 1.66), whereas females over thirty years old had a higher incidence compared with their male counterparts (incidence rate ratio, 2.03; 95% confidence interval, 1.65 to 2.65). Compared with the Hispanic race, the black and white races were associated with substantially higher rates of ankle sprain (incidence rate ratio, 3.55 [95% confidence interval, 1.01 to 6.09] and 2.49 [95% confidence interval, 1.01 to 3.97], respectively). Nearly half of all ankle sprains (49.3%) occurred during athletic activity, with basketball (41.1%), football (9.3%), and soccer (7.9%) being associated with the highest percentage of ankle sprains during athletics. CONCLUSIONS An age of ten to nineteen years old is associated with higher rates of ankle sprain. Males between fifteen and twenty-four years old have higher rates of ankle sprain than their female counterparts, whereas females over thirty years old have higher rates than their male counterparts. Half of all ankle sprains occur during athletic activity.

Epidemiology of shoulder dislocations presenting to emergency departments in the United States.

BACKGROUND The epidemiology of traumatic shoulder dislocations is poorly understood. The aim of the current study was to determine the incidence of shoulder dislocations presenting to hospital emergency departments in the United States and define demographic risk factors for these injuries. METHODS The National Electronic Injury Surveillance System, a probability sample of all injuries presenting to emergency departments in the United States, was queried for shoulder dislocations from 2002 through 2006. Patient and injury characteristics were analyzed. United States Census data were utilized to calculate incidence rates for the United States population and subgroups. Incidence rate ratios were then calculated with respect to age, sex, and race. RESULTS A total of 8940 shoulder dislocations were identified, resulting in an overall incidence rate in the United States of 23.9 (95% confidence interval, 20.8 to 27.0) per 100,000 person-years. The male incidence rate was 34.90 (95% confidence interval, 30.08 to 39.73) per 100,000 person-years, with an incidence rate ratio of 2.64 (95% confidence interval, 2.39 to 2.88) relative to the female incidence rate. It was found that 71.8% of the dislocations were in males. Stratified by decade, the maximum incidence rate (47.8 [95% confidence interval, 41.0 to 54.5]) occurred in those between the ages of twenty and twenty-nine years; 46.8% of all dislocations were in patients between fifteen and twenty-nine years of age. There were no significant differences based on race. Dislocations most frequently resulted from a fall (58.8%) and occurred at home (47.7%) or at sites of sports or recreation (34.5%). Overall, 48.3% of injuries occurred during sports or recreation. CONCLUSIONS The estimated incidence rate of shoulder dislocations in the United States is 23.9 per 100,000 person-years, which is approximately twice the previously reported value. A young age and male sex are risk factors for shoulder dislocation in the United States population.

The Incidence and Characteristics of Shoulder Instability at the United States Military Academy

Background The literature provides little information detailing the incidence of traumatic shoulder instability in young, healthy athletes. Hypothesis Shoulder instability is common in young athletes. Study Design Descriptive epidemiologic study. Methods We prospectively captured all traumatic shoulder instability events at the United States Military Academy between September 1, 2004, and May 31, 2005. Throughout this period, all new traumatic shoulder instability events were evaluated with physical examination, plain radiographs, and magnetic resonance imaging. Instability events were classified according to direction, chronicity, and type (subluxation or dislocation). Subject demographics, mechanism of injury, and sport were evaluated. Results Among 4141 students, 117 experienced new traumatic shoulder instability events during the study period; 11 experienced multiple events. The mean age of these 117 subjects was 20.0 years; 101 students were men (86.3%), and 16 were women (13.7%). The 1-year incidence proportion was 2.8%. The male incidence proportion was 2.9% and the female incidence proportion was 2.5%. Eighteen events were dislocations (15.4%), and 99 were subluxations (84.6%). Of the 99 subluxations, 45 (45.5%) were primary events, while 54 (54.5%) were recurrent. Of the 18 dislocations, 12 (66.7%) were primary events, while 6 (33.3%) were recurrent. The majority of the 117 events were anterior in nature (80.3%), while 12 (10.3%) were posterior, and 11 (9.4%) were multidirectional. Forty-four percent (43.6%) of the instability events experienced were as a result of contact injuries, while 41.0% were a result of noncontact injuries, including 9 subluxations caused by missed punches during boxing; information was unavailable for the remaining 15%. Conclusion Glenohumeral instability is a common injury in this population, with subluxations comprising 85% of instability events.

Incidence of Glenohumeral Instability in Collegiate Athletics

Background Glenohumeral instability is a common injury sustained by young athletes. Surprisingly, little is known regarding the incidence of glenohumeral instability in collegiate athletes or the relevant risk factors for injury. A better understanding of the populations most at risk may be used to develop preventive strategies. Hypothesis The incidence of glenohumeral instability in collegiate athletics is high, and it is affected by sex, sport, type of event, and mechanism of injury. Study Design Descriptive epidemiologic study. Methods The National Collegiate Athletic Association injury database was queried for all glenohumeral instability events occurring between the years 1989 and 2004. An analysis of the injuries was performed by sport, activity (competition versus practice), sex, type of event (primary versus recurrent), mechanism of injury, and time loss from athletic performance. Incidence rates and incidence rate ratios were calculated. Results A total of 4080 glenohumeral instability events were documented for an incidence rate of 0.12 injuries per 1000 athlete exposures. The sport with the greatest injury rate was mens spring football, with 0.40 injuries per 1000 athlete exposures. Overall, athletes sustained more glenohumeral instability events during games than practices (incidence rate ratio [IRR], 3.50; 95% confidence interval [CI], 3.29-3.73). Male athletes sustained more injuries than did female athletes (IRR, 2.67; 95% CI, 2.43-2.93). Female athletes were more likely to sustain an instability event as the result of contact with an object (IRR, 2.43; 95% CI, 2.08-2.84), whereas male athletes were more likely to sustain an event from player contact (IRR, 2.74; 95% CI, 2.31-3.25). Time lost to sport (>10 days) occurred in 45% of glenohumeral instability events. Conclusion Glenohumeral instability is a relatively common injury sustained by collegiate athletes. More injuries occurred during competition and among male athletes.

Incidence of Shoulder Dislocation in the United States Military: Demographic Considerations from a High-Risk Population

BACKGROUND Little is known of the incidence of shoulder instability, despite some evidence that it may be a common injury in young, athletic individuals. The goal of this study was to determine the incidence of shoulder dislocation in United States military personnel, as well as to identify the demographic risk factors for injury. METHODS We performed a query of the Defense Medical Epidemiology Database with the code from the International Classification of Diseases, Ninth Revision, for acute shoulder dislocation for the years 1998 through 2006. An overall injury incidence was calculated, in addition to multivariate analysis, to determine independent risk factors among the following demographic considerations: sex, race, branch of military service, rank, and age. RESULTS The overall incidence rate was 1.69 dislocations per 1000 person-years. Significant demographic risk factors were male sex, white race, service in the Army, junior enlisted rank, and an age of less than thirty years (p<0.0001). CONCLUSIONS The incidence of shoulder instability among U.S. military personnel (1.69 per 1000 person-years) is considerably higher than previous reports for the general U.S. population (0.08 per 1000 person-years). Male sex, white race, and an age of less than thirty years were significant independent risk factors for injury.

Epidemiology of Ankle Sprain at the United States Military Academy

Background Ankle sprain is a common injury in athletic populations that results in significant time lost to injury. Hypothesis The incidence rates (IRs) of ankle ligament sprains are influenced by gender, height, weight, body mass index (BMI), physical conditioning, level of competition, type of sport, and athlete exposure to sport. Study Design Cohort study; Level of evidence, 2. Methods A longitudinal cohort study was performed to determine the effect of risk factors for ankle sprain at the United States Military Academy between 2005 and 2007. Results A total 614 cadets sustained new ankle sprains during 10 511 person-years at risk, resulting in an overall IR of 58.4 per 1000 person-years. Women (96.4), compared with men (52.7), had a significantly increased rate ratio (IRR) for ankle sprain of 1.83 (95% confidence interval [CI], 1.52-2.20). Men with ankle sprains had higher mean height, weight, and BMI than uninjured men (P < .001). Men with ankle sprains had higher average scores in push-ups, sit-ups, and run time than uninjured men (P < .001). Ankle sprain occurred most commonly during athletics (64.1%). Ankle sprain IR did not significantly differ between intercollegiate and intramural athletic competition after controlling for athlete-exposure (IRR, 1.05; 95% CI, 0.81-1.37). The ankle sprain IRR of female compared with male intercollegiate athletes was 0.93 (95% CI, 0.67-1.32) per 1000 person-years and 1.04 (95% CI, 0.74-1.47) per 1000 athlete-exposures. The intercollegiate sports of mens rugby, womens cheerleading, and mens/womens basketball, soccer, and lacrosse had the highest ankle sprain IR. Conclusion Higher mean height and weight in men, increased BMI in men, greater physical conditioning in men, and athlete exposure to selected sports were all risk factors for ankle sprain.

Long-term Follow-up of Acute Arthroscopic Bankart Repair for Initial Anterior Shoulder Dislocations in Young Athletes

Background Little is known of the long-term results of acute arthroscopic Bankart repair for first-time traumatic anterior glenohumeral dislocations. Hypothesis Acute arthroscopic Bankart repair for first-time traumatic anterior glenohumeral dislocations will provide good results at long-term follow-up. Study Design Case series; Level of evidence, 4. Methods The authors evaluated a cohort of young patients who sustained first-time anterior glenohumeral dislocations and were acutely treated with arthroscopic Bankart repair using bioabsorbable tacks. Subjective outcome measures were obtained at a mean follow-up of 11.7 years (range, 9.1-13.9 years). Results Thirty-nine patients (40 shoulders) were available of the original cohort of 49 shoulders (82%). Two of the 9 who were lost to follow-up had revision surgery before being lost and are carried forward in the calculations of recurrent instability and revision surgery but are not included in the calculation of the functional scores. The mean Single Assessment Numeric Evaluation was 91.7, the mean Western Ontario Shoulder Instability score was 371.7, the mean subjective Rowe score was 25.3, the mean Simple Shoulder Test was 11.1, the mean American Shoulder and Elbow Society score was 90.9, the mean Short Form-36 Physical Component score was 94.4, and the mean Tegner score was 6.5. Six patients sustained recurrent dislocations for a redislocation rate of 14.3%. Nine patients (21.4%) reported experiencing subluxation events. Six patients (14.3%) underwent revision stabilization surgery. Conclusion At long-term follow-up, acute arthroscopic Bankart repair for first-time traumatic anterior glenohumeral dislocations resulted in excellent subjective function and return to athletics in young, active patients with an acceptable rate of recurrence and reoperation.

Epidemiology of Major League Baseball Injuries

Background Little is known about the injury rates in Major League Baseball (MLB) players, as a formal injury surveillance system does not exist. The goal of this study was to characterize the epidemiology of MLB injuries over a 7-year period. Hypothesis Injuries in MLB would be common. Study Design Descriptive epidemiologic study. Methods The authors analyzed the MLB disabled list data from 2002 through 2008. Injuries were analyzed for differences between seasons, as well as during seasons on a monthly basis. The injuries were categorized by major anatomic zones and then further stratified based on injury type. Position-specific subanalyses for pitcher and position players were performed. Results From the 2002 season through the 2008 season, an average of 438.9 players per year were placed on the disabled list, for a rate of 3.61 per 1000 athlete-exposures. There was a significant 37% increase in injuries between 2005 and 2008. The highest injury rate during the season was during the month of April (5.73/1000 exposures) and the lowest in September (0.54/1000 exposures). No differences were noted in the injury rates between the National League and the American League (incidence rate ratio [IRR] = 1.06; 95% confidence interval [CI] = 0.98, 1.15). Pitchers experienced 34% higher incidence rates for injury compared with fielders during the study period (IRR = 1.34; 95% CI = 1.25, 1.44). Among all player injuries, upper extremity injuries accounted for 51.4% while lower extremity injuries accounted for 30.6%. Injuries to the spine and core musculature accounted for 11.7% while other injuries and illnesses were 6.3% of the total disabled list entries. There was a significant association between position played and anatomic region injured (P < .001), with pitchers experiencing a significantly greater proportion of injuries to the upper extremity (67.0%; 95% CI = 63.1%, 70.9%) compared with fielders (32.1%; 95% CI = 29.1%, 35.1%). Conversely, fielders experienced a significantly greater proportion of injuries to the lower extremity (47.5%; 95% CI = 43.8%, 51.1%) compared with pitchers (16.9%; 95% CI = 14.9%, 18.8%). The mean number of days on the disabled list was 56.6. Overall, a greater proportion of disability days were experienced by pitchers (62.4%; 95% CI = 62.0%, 62.8%; P < .001) compared with fielders (37.6%; 95% CI = 37.3%, 37.9%). Conclusion Injuries in MLB resulting in disabled list designation are common. Upper extremity injuries were predominant in pitchers, while lower extremity injuries are more common in position players. These data may be used in the development of a formal MLB injury database, as well as in the development and implementation of specific preseason training and in-season conditioning for injury prevention.