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By M. Jo McMullen, Senior Attending Staff Physician, Department of Emergency Medicine, Akron General Medical Center, Akron, Ohio; Professor of Clinical Emergency Medicine, Northeast Ohio Universities College of Medicine, Rootstown, Ohio; and Tactical Physician, Metro SWAT and Akron, Ohio, Police Department; and C. J. Williams, Research Coordinator, Department of Emergency Medicine, Akron General Medical Center, Akron, Ohio
aw enforcement administrators are expected to make decisions regarding requirements for personal body armor for their employees. Although cost and comfort are significant factors, the level of protection necessary to defeat the expected threat level must remain the primary consideration. The development of Kevlar by the DuPont Chemical Company in 1971 allowed the development of personal body armor that was light enough in weight for routine wear and yet strong enough to stop a .38-caliber lead bullet or a .22-caliber rifle round. The U.S. Department of Justice’s National Institute of Justice (NIJ) Technology Assessment Program, now the National Law Enforcement and Corrections Technology Center (NLECTC), began a program of developing testing standards for this new technology. Many, if not most, law enforcement personnel are unaware of the background of that system. For a vest to be certified against a specific bullet type and velocity, the following criteria must be met: the vest panel must prevent penetration from the impact of six bullets spaced at least two inches apart and three inches from the edge of the vest. In addition, the deflection caused by the backface deforming into a clay block must not exceed 44 millimeters, or 1.73 inches.1 During the early development phase, the researchers concluded that even though a bullet was stopped by the vest, the impact would at least leave a severe bruise and could theoretically kill by damaging underlying organs. This standard was designed to ensure a 95 percent probability of survival, with no more than a 10 percent probability of requiring surgery. The design development needed to find a balance between officer survival and a vest that was light enough and comfortable enough that it would actually be worn by line officers.2 Studies performed on animals shot while wearing Kevlar vests demonstrated fractured ribs and vertebrae; lacerations of the liver, spleen, and kidney; and contusions of the lungs and myocardium. 3 Although newer fibers have been developed with increased tensile strength and less weight, the original studies have not been repeated on these newer materials. These studies continue to be the basis for the recommendations for the medical care of officers shot wearing a vest in the NIJ guide titled Selection and Application Guide to Personal Body Armor.4
Research
Despite data to suggest the potential for injury, there are no large studies describing injuries sustained while wearing vests. A review of current textbooks in emergency medicine, surgery, and trauma reveals no discussion of injuries under personal body armor. Even textbooks dealing specifically with gunshot wounds fail to mention these injuries. There are a few individual human case studies and several single case reenactments.5
Over 3,000 lives have been saved since the first officer was shot wearing a modern vest in 1972. Over 70 percent of law enforcement agencies report issuing body armor to all officers, and 53 percent required the vest to be worn on duty. Although frequently referred to as “bulletproof vests,” in reality the vests do not stop all rounds fired. Of the 54 officers slain with firearms in 2004, 31 were wearing body armor. In four cases, bullets penetrated though the vest, and a fifth died of a nonpenetrating blunt force trauma to the chest.6 Even when the round is stopped, an officer can suffer an injury under the vest. The objective of this study is to describe the frequency, nature, and severity of nonfatal ballistic injuries sustained by police officers while wearing personal body armor. This protocol was approved by the Akron General Medical Center Institutional Research Review Board. There is no mandatory reporting of injuries to police officers. While most U.S. law enforcement agencies report to the Federal Bureau of Investigation (FBI) under the Uniform Crime Reporting program, this databank does not specifically separate officers shot and injured wearing personal body armor. This study uses two industry databases: the IACP/DuPont Kevlar Survivors’ Club and the Second Chance Saves.7 Figure 1 explains how the database used for this study was built.
| The question of whether a vest was rated to stop the level of threat was frequently difficult to ascertain. The Department of Justice (DOJ) vest rating system uses the caliber of the round, the bullet weight, the velocity of the shot, and the composition and coating of the bullet. Most officers knew the caliber of the bullet that struck them but in most cases did not know anything about the weight or velocity. The angle of entry is also calculated in testing but was not available in actual shootings unless the shooting was reconstructed. In entering the data, the vest was considered to be rated for the level of threat unless it was clearly not. By using the positive rating as a default when a caliber was listed for more than one vest level, the number of vest failures is maximized. Not all data fields were available for each event—particularly where the data were abstracted from files.
Data Analysis
Two sources were used to obtain the data. For the survey, 332 officers were contacted. Data from 136 additional cases were reviewed using only files. All data involved events occurring in the United States involving sworn police officers between the years of 1972 and 2002. Shootings involved handguns (77 percent), shotguns (13 percent), and rifles (6 percent), with 4 percent of shootings coming from unknown firearms. Officers were struck from 1 to 36 times; 75 percent were shot only once or twice. Distances varied from direct contact to 300 feet; 55 percent were shot within six feet.
Injuries were defined as none; minor (bruising, skin abrasion); moderate (bruise to internal organs, bone fracture, deep softtissue injury); or major (body cavity penetration). Of officers wearing a vest rated for the threat level, 85 percent sustained minor or no injuries (see table 1). Officers whose vests were rated for the assault level were less likely to sustain major injuries (odds ratio 2.12; 95 percent confidence that the statistics are accurate as stated). Officers who were obese showed a trend to sustain moderate or major injuries, but this trend was not statistically significant (see tables 2–3). | |  | | Note: Data include only officers wearing vests rated to stop the threat with injuries that could be categorized |
 | | Note: Data include only officers wearing vests not rated to stop the threat with injuries that could be categorized. |
Sixty percent of officers who received any medical evaluation were treated and released from the emergency department (ED). Of the officers admitted to the hospital, medical care was needed variably for injuries either under the vest or not associated with the vest, or both. For example, one officer who sustained only a minor injury to his chest had a complex hand injury requiring several surgeries. The compiled data could not separate the number of days in the hospital and off work for each injury. For officers admitted to the hospital, the length of stay ranged from 1 to 180 days, with half the officers being discharged by day 2. Officers were off duty 0 to 730 days, with 50 percent returning to work within two weeks.
There were two unexpected findings: a unique backface deformity injury to the abdomen and delayed injuries. Backface injuries, also known as behind-armor blunt trauma (BABT), were reported on the chest as early as 1978.8 A 2001 review looked at the proposed mechanism of chest wall BABT.9 Abdominal-wall injuries have not been described previously. | The backface deformity injury over the abdomen produced a wound that appeared on the surface to be a gunshot wound. When the bullet strikes but does not perforate the vest, it can penetrate soft tissue, pushing the bullet, vest, and clothing inward (see figure 2). When the vest is removed, the vest material and bullet come back out, leaving a hole that looks like a bullet wound. In spite of not finding a bullet on an X-ray, and in one case a negative CT scan, six officers underwent exploratory laparotomies, which appear to have been unnecessary, as the officers reported no significant findings. One officer’s partner went back to the scene from the hospital, brought the vest back to show the surgeon, and prevented an unnecessary surgery.Several delayed injuries were reported. The only report of a delayed injury to an internal organ was a malrotation of the stomach found several years after the shooting, attributed by the surgeon as due to the blunt force trauma. Two abdominal-wall hernias were found over a year after each shooting. One cervical disc injury, located directly under the area of impact, was found during an MRI scan several years after the shooting, as well as one thoracic spine disc injury and one case of three ruptured discs. Officers also blamed blunt force trauma for two cases of arthritis, one bone infection, and one case of new-onset severe hypertension.
Significance of the Study Results
These data are limited in that they represent about 50 percent of the officers identified by these databases as having been shot. It is further limited by the fact that it is a retrospective review based on officers’ recollection of events occurring as long ago as 30 years before the time of the survey. However, this is clearly a sentinel event in an officer’s life,10 and recollections were predominantly consistent with data collected at the time (for example, in the Second Chance files). Ballistic vest testing is very structured, including the weight and velocity of the round, the angle of entry, and the pattern and spacing of shots. The testing is performed on new material, which is generally warranted by the manufacturer for five years. The full amount of these data was usually not available in this study’s attempts to determine if a vest was rated for a given threat.
Even with these limitations, this study has created the only database of its kind, and the information provides the first medical data to support the findings of the animal studies of the 1970s. An estimate of not more than 10 percent of officers struck requiring surgery is consistent with our findings of 15 percent of officers with moderate and major injuries, many of which did not require surgery. Law enforcement officers and their departments need to be aware that these are not “bulletproof vests.” Both vest failures and backface injuries do occur.
Recommendations
It is important to reiterate the DOJ admonition that officers shot in the vest seek medical attention.11 In any incident involving gunfire, all officers on the scene should be encouraged to check their vests. Officers’ physical responses to being shot varied widely:
- ”I didn’t know I was shot. I found the bullet embedded in the vest three days later when I was cleaning my gear.”
- ”It spun me around.”
- ”It knocked me down.”
It is clear that all officers who are shot in the vest area, regardless of their symptoms at the scene, need a medical evaluation due to the potential for occult or delayed injuries. One officer who declined medical care at the scene went to his ophthalmologist the next day for persistent eye pain. The doctor found a bullet fragment embedded in the eye. Some of the responses were psychological in nature rather than physical. Offering/requiring medical care should help give appropriate significance to an officer’s situation. Although agencies are increasingly acknowledging the significance of posttraumatic stress, it may take a physician telling an officer and/or the agency that the officer needs counseling before returning to work. Many officers brought up psychosocial issues during the study, frequently unresolved years after the event. If at all possible, after a shooting, the vest should accompany the injured officer to the hospital, so the physician can get a better idea of the area involved and the mechanism of injury. Although legal issues regarding chain of custody must be addressed, the potential to improve the physician’s assessment and possibly forestall unnecessary testing or surgery is paramount. Hopefully the agency involved has access to a physician who is knowledgeable in this area and can help guide the ED physician, who may or may not be aware of these types of injuries. Most recommendations for evaluation of the officer include an electrocardiogram (EKG). There were no documented cases of myocardial contusion (bruising of the heart) in this study’s data. However, in most cases, the examining physician usually did not look for this. Serial EKGs, cardiac monitoring, and blood tests for cardiac enzymes would seem to be reasonable if the area struck was over the sternum or the left anterior chest. Serial chest X-rays have also been recommended. However, a CT scan of the chest may be more appropriate, as it will pick up smaller amounts of free air or blood as well as bruises to the lung tissue. There are no valid guidelines to determine whether an officer should be admitted to the hospital. A six-hour observation period in the ED is probably reasonable. With more sophisticated testing currently available, such as CT scans, it is hoped that unnecessary surgery can be avoided.
Conclusions
Officers who are shot wearing personal body armor are significantly protected from major injury. However, both perforation of the vest with penetrating trauma and backface blunt trauma injuries do occur about 10–15 percent of the time. Both occult and delayed injuries have been described. All such officers should be required to seek immediate medical attention. Physicians should direct their assessments based on an understanding of the types of injuries possible as well as their physical exams. ■
Notes: 1U.S. Department of Justice, Office of Justice Programs, National Institute of Justice, Selection and Application Guide to Personal Body Armor, NIJ Guide 100-01, NCJ 189633 (Rockville, Maryland: National Law Enforcement and Corrections Technology Center, November 2001), 31–33, http://www.ncjrs.gov/pdffiles1/nij/189633.pdf (accessed June 19, 2008).
2National Institute of Justice, Selection and Application Guide to Personal Body Armor, 6; and Alexander Jason and Martin L. Fackler, Body Armor Standards: A Review and Analysis, 2nd ed. (Pinole, California: Center for Ballistic Analysis, 1990), 3–7.
3See Michael A. Goldfarb et al., Body Armor Medical Assessment (Washington, D.C.: U.S. Department of Justice, Law Enforcement Assistance Administration, National Institute of Law Enforcement and Criminal Justice, May 1976); Ewa Lidén et al., “Some Observations Relating to Behind-Body Armour Blunt Trauma Effects Caused by Ballistic Impact,” Journal of Trauma 28, Suppl. 1 (1988): S145–S148; and Kevin J. O’Connell et al., “The Shielding Capacity of the Standard Military Flak Jacket against Ballistic Injury to the Kidney,” Journal of Forensic Sciences 33, no. 2 (1988): 410–417.
4National Institute of Justice, Selection and Application Guide to Personal Body Armor, 70.
5See Andrew W. Carroll and Carl A. Soderstrom, “A New Nonpenetrating Ballistic Injury,” Annals of Surgery 188, no. 6 (1978): 753–757; George E. Thomas, “Fatal .45-70 Rifle Wounding of a Policeman Wearing a Bulletproof Vest,” Journal of Forensic Sciences 27, no. 2 (1982): 445–449; L. Cannon, “Behind Armour Blunt Trauma: An Emerging Problem,” Journal of the Royal Army Medical Corps 147, no. 1 (2001): 87–96; and Thomas E. Bachner Jr., “Life-Threatening Blunt Trauma,” Straight from the Heart (newsletter of Second Chance, Inc.), Spring 2000.
6U.S. Department of Justice, Federal Bureau of Investigation, Law Enforcement Officers Killed and Assaulted 2004, http://www.fbi.gov/ucr/killed/2004/openpage.htm(accessed June 19, 2008).
7On August 2, 2005, Second Chance was acquired by Armor Holdings, Inc. See http://www.secondchance.com/news.asp?action=article&newsID=88 (accessed June 27, 2008).
8Carroll and Soderstrom, “A New Nonpenetrating Ballistic Injury.”
9Cannon, “Behind Armour Blunt Trauma: An Emerging Problem.”
10In medicine, a sentinel event is defined as an unexpected event that results or can result in serious or life-threatening physical or psychological injury.
11National Institute of Justice, Selection and Application Guide to Personal Body Armor, 70.
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From The Police Chief, vol. LXXV, no. 8, August 2008. Copyright held by the International Association of Chiefs of Police, 515 North Washington Street, Alexandria, VA 22314 USA. |
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