Nonpenetrating Injury Research Articles

Exposure of swine to nonpenetrating blast results in reactive astrogliosis, fiber degeneration, and upregulation of inflammatory markers

Blast‐induced nonpenetrating brain injury (bTBI) has become increasingly prevalent in recent years. The arsenal of available treatments continues to be inadequate while the mechanism of injury remains equivocal. Although similar studies have been reported on small animal models using fluid percussion and weight‐driven devices, none have been conducted on large animals under real‐world conditions. We exposed swine to varying levels of focused explosions within a shock tube in order to quantify the intensities needed to produce minimum detectable and maximum survivable bTBI. In addition, improvised explosive devices were detonated near swine placed within a surrogate Humvee, in a simulated building/street setting, or in an open‐field scenario. All animals were exposed left‐laterally to incident explosion. Early histological findings are distinctly different from other causes of TBI and include activation of astrocytes in the hippocampus and overlapping fiber tracts as well as fiber degeneration in the thalamus and anterior cerebellar vermis, that do not clearly correlate with exposure lateralization. Preliminary proteomic analyses of cerebrospinal fluid, blood and brain tissue indicate blood‐brain barrier disruption along with a prominent inflammatory response.

Efficacy and feasibility of acupuncture for patients in the ED with acute, nonpenetrating musculoskeletal injury of the extremities

Objectives We conducted a pilot study to assess the efficacy of acupuncture as an analgesic intervention for patients presenting to the emergency department (ED) after minor acute trauma to the extremities. In addition, we sought to assess the feasibility of performing acupuncture in this setting. Methods Acupuncture was used as primary analgesia for a convenience sample of ED patients with acute, nonpenetrating extremity injury. Efficacy was measured using a visual analog scale before treatment, immediately after acupuncture (time 0), and every 30 minutes thereafter. A telephone call was made to patients within 72 hours to ascertain pain levels using a 0 to 10 numerical rating scale. Markers of feasibility included average time patients spent in the fast track area of the ED vs average time in the department (TID) for all fast track patients with similar injury. Results Of 47 patients approached, 20 (43%) consented to participate. The mean age of those who consented was 33 years, and 70% (n = 14) were male. Median change in visual analog scale score for preacupuncture vs time 0 was 16 mm, with range of 0 to 60 mm. Median numerical rating scale score at time of discharge and at follow-up was 3. Median TID was 135 minutes, with a range of 55 to 255 minutes. Patients with extremity injury who did not receive acupuncture had a median TID of 90 minutes. Conclusions This study suggests that acupuncture can be an effective analgesic intervention for patients with acute injury to the extremities. Acupuncture did not increase patients' TID. Minor complications were reported.

Posttraumatic epilepsy: The endophenotypes of a human model of epileptogenesis

Posttraumatic epilepsy is a common complication of traumatic brain injury (TBI), occurring in up to 15-20% of patients with severe brain trauma. Trauma accounts for approximately 5% of chronic epilepsy in the community. Because it is a common condition, and because of the relatively short latency period between injury and onset of chronic seizures, posttraumatic epilepsy represents a good model to test antiepileptogenic therapies. However, several well-conducted clinical trials have failed to demonstrate antiepileptogenic efficacy for several common anticonvulsants. Posttraumatic epilepsy can arise through a number of mechanisms, which often coexist within a single patient. Penetrating brain injury produces a cicatrix in the cortex and is associated with a risk of posttraumatic epilepsy of approximately 50%, whereas nonpenetrating head injury may produce focal contusions and intracranial hemorrhages, and is associated with a risk of posttraumatic epilepsy of up to 30%. Furthermore, closed head injury often produces diffuse concussive injury, with shearing of axons and selective damage to vulnerable brain regions, such as the hippocampus. The clinical, neurophysiologic, imaging, and neuropathologic features or epileptogenicity differ between these alternate mechanisms. It is likely that better understanding of the subtypes of epilepsy resulting from brain trauma will be required to successfully identify antiepileptogenic therapies.

Muscle Injury, Vimentin Expression, and Nonsteroidal Anti‐inflammatory Drugs Predispose to Cryptic Group A Streptococcal Necrotizing Infection

Myonecrosis due to group A streptococci (GAS) often develops at sites of nonpenetrating muscle injury, and nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the severity of these cryptic infections. We have previously shown that GAS bind to vimentin on injured skeletal muscles in vitro. The present study investigated whether vimentin up-regulation in injured muscles in vivo is associated with homing of circulating GAS to the injured site and whether NSAIDs facilitate this process. M type 3 GAS were delivered intravenously 48 h after eccentric contraction (EC)-induced injury of murine hind-limb muscles. Vimentin gene expression and homing of GAS were followed by real-time reverse-transcriptase polymerase chain reaction and quantitative bacteriology of muscle homogenates, respectively. In separate experiments, ketorolac tromethamine (Toradol) was given 1 h before GAS infusion. Vimentin was up-regulated approximately 8-fold 48 h after EC. Significantly more GAS were found in moderately injured muscles than in noninjured controls. NSAIDs greatly augmented the number of GAS in injured muscles. Vimentin may tether circulating GAS to injured muscle, and NSAIDs enhance this process. Strategies targeting the vimentin-GAS interaction may prevent or attenuate GAS myonecrosis. Use of NSAIDs should increase suspicion of cryptic GAS infection in patients with increasing pain at sites of nonpenetrating muscle injury.

Soft tissue injuries: 4 Hip and thigh

In this fourth paper in the Soft Tissue Injury series we cover aspects of soft tissue injury relating to the hip. Our understanding of injuries to the hip and thigh...

Traumatic Lower Extremity Arteriovenous Fistulae in Children

Traumatic arteriovenous fistulae are rare injuries in the pediatric population. Most are caused by penetrating injuries or are post-surgical in nature. Fistulae resulting from non-penetrating injuries are often missed early in the course of physical examination. This occurs due to the absence of clinical signs of arterial or venous injury, despite the close proximity of the affected vessels to point of injury. Likewise, signs and symptoms of post-surgical vascular injury may be difficult to discern from normal postoperative discomfort. The astute clinician must be on alert for unusual presentations of vascular injury to intervene in an expeditious manner. This article presents a series of vascular complications following either blunt injury or surgical management of the lower extremity in children who presented to our facility between November 2004 and December 2005.

Bilateral Vagotomy Inhibits Apnea and Attenuates Other Physiological Responses After Blunt Chest Trauma

Behind armor blunt trauma (BABT) is defined as the nonpenetrating injury resulting from a ballistic impact on body armor. Some of the kinetic energy is transferred to the body, causing internal injuries and, occasionally, death. The aim of this study was to investigate if apnea and other pathophysiological effects after BABT is a vagally mediated reflex. Sixteen anesthetized pigs wearing body armor, of which five were vagotomized, were shot with a standard 7.62 mm assault rifle. These animals were compared with control animals (n = 8), shot with blank ammunition. We performed bilateral vagotomy before the shot and assessed the outcome on the apnea period, respiration, circulation, and brain function. Animals were monitored during a 2-hour period after the shot. Nonvagotomized animals had a mean apnea period of 22 (6-44) seconds. This group also showed a significant decrease in oxygen saturation compared with control animals. Furthermore, electroencephalogram-changes were more pronounced in nonvagotomized animals. In contrast, vagotomized animals were protected from apnea and showed only a minor decrease in oxygen saturation. All exposed animals showed impaired circulation, and postmortem examination revealed a pulmonary contusion. This study shows that apnea after BABT is a vagally mediated reflex that can be inhibited by bilateral vagotomy. Our results indicate that the initial apnea period is an important factor for hypoxia after BABT. Supported ventilation should begin immediately if the affected person is unconscious and suffers from apnea. It should continue until the neurologic paralysis disappears and sufficient spontaneous breathing begins.

Postmortem computed tomography findings as evidence of traffic accident-related fatal injury

Most traumatic deaths in Japan are due to nonpenetrating injuries, especially those that result from traffic accidents; however, the autopsy rate of traffic accident-related deaths is only about 5%. We investigated the diagnostic ability of postmortem computed tomography (PMCT) in cases of fatal trauma after traffic accidents. Our subjects were 78 subjects (59 males, 19 females; mean age 50 years, range 15-87 years) who were brought to our institution in cardiopulmonary arrest on arrival after traffic accidents and died despite resuscitation attempts. PMCT findings of damage to the head, neck, thorax, abdomen, and pelvis were classified into three grades according to the Abbreviated Injury Scale (AIS) severity: A: 1 (minor), 2 (moderate); B: 3 (serious), 4 (severe), 5 (critical); C: 6 (maximum). The percentage ratio of A/B/C in 78 head injuries was 32/60/8, in 41 neck injuries 83/5/12, in 76 thorax injuries 5/38/57, in 76 abdominal injuries 70/24/7, and in 76 pelvic injuries 79/21/0, respectively. PMCT can detect or presume fatal trauma when diagnosing the cause of death after traffic accidents.

Assessing Behind Armor Blunt Trauma (BABT) Under NIJ Standard-0101.04 Conditions Using Human Torso Models

Although soft armor vests serve to prevent penetrating wounds and dissipate impact energy, the potential of nonpenetrating injury to the thorax, termed behind armor blunt trauma, does exist. Currently, the ballistic resistance of personal body armor is determined by impacting a soft armor vest over a clay backing and measuring the resulting clay deformation as specified in National Institute of Justice (NIJ) Standard-0101.04. This research effort evaluated the efficacy of a physical Human Surrogate Torso Model (HSTM) as a device for determining thoracic response when exposed to impact conditions specified in the NIJ Standard. The HSTM was subjected to a series of ballistic impacts over the sternum and stomach. The pressure waves propagating through the torso were measured with sensors installed in the organs. A previously developed Human Torso Finite Element Model (HTFEM) was used to analyze the amount of tissue displacement during impact and compared with the amount of clay deformation predicted by a validated finite element model. All experiments and simulations were conducted at NIJ Standard test conditions. When normalized by the response at the lowest threat level (Level I), the clay deformations for the higher levels are relatively constant and range from 2.3 to 2.7 times that of the base threat level. However, the pressures in the HSTM increase with each test level and range from three to seven times greater than Level I depending on the organ. The results demonstrate the abilities of the HSTM to discriminate between threat levels, impact conditions, and impact locations. The HTFEM and HSTM are capable of realizing pressure and displacement differences because of the level of protection, surrounding tissue, and proximity to the impact point. The results of this research provide insight into the transfer of energy and pressure wave propagation during ballistic impacts using a physical surrogate and computational model of the human torso.

Effects of fire on small commercial gas cylinders

Current standards on the safety of small portable gas cylinders only define the pressures at temperatures of up to 50 °C and therefore have limited applicability in situations where cylinders are close to fires. Cylinders containing a pressurised liquid butane–propane mixture were heated in a small barbecue. The cylinders underwent a boiling liquid expanding gas explosion (BLEVE) at a liquid temperature of 90–100 °C. Failure was at the rolled seam where gas could escape thus provoking the BLEVE. Previous hydrostatic pressure testing of the cylinders showed that collapse of the spherical cap base occurred at a pressure of 1.8 MPa and that this was followed by failure of the rolled seam at a pressure of 2.0 MPa. These pressures were lower than that required to produce longitudinal cracks in the cylinder wall. Analysis of the pressure created as the temperature is raised by means of the Clausius–Clapeyron equation indicated the temperature for failure of the seam to be about 100 °C. After the BLEVE the cylinder broke into two fragments, an end cap and a tub rocket. The velocity of the tub rocket was estimated to be 65 m s −1, giving a kinetic energy of 309 J. By comparison with the ballistics of rubber bullets it is believed that any injuries will be non-penetrating blunt trauma injuries and be less likely to cause severe injuries than those created by rubber bullets. The range over which the kinetic energy is likely to be capable of creating injuries is estimated to be less than 30 m.

Cerebral Saccular Aneurysm Rupture After Head Injury

When seen after head trauma, subarachnoid hemorrhage (SAH) often leads to an angiogram to look for vascular injury. Usually the study is negative; sometimes a traumatic aneurysm or dissection is seen. Occasionally, a conventional saccular aneurysm is found. The clinical history, physical examination, and computed tomography (CT) scan in such a patient may suggest that an aneurysmal SAH was the primary event, with the trauma resulting from SAH-associated incapacity. But this scenario is not usually apparent and, if a saccular cerebral aneurysm is found on angiogram after a patient has been injured, it is often difficult to know if the aneurysm is incidental, caused the SAH and trauma, or bled as a result. Most traumatic aneurysms in the carotid distribution are located at the base of the skull and are associated with skull fractures. Those located inside the cranium proper that result from nonpenetrating injury are less often linked to skull fractures. They are likely caused by contusion of the vessel, in which there is stretching or torsion of the wall. By analogy, similar forces acting on the wall of pre-existing cerebral aneurysms should cause some to bleed. Given a conservative estimate that 2% of the population harbors unruptured saccular aneurysms, a certain percentage of traumatic SAH must be caused by trauma-induced aneurysmal rupture. A couple of published case reports have verified this mechanism, though the intensity of the trauma in these cases was quite severe. The case presented here suggests that, if SAH is seen after trauma in a pattern suggestive of aneurysmal rupture, there should be a low threshold for looking for and treating “nontraumatic” saccular aneurysms. Mild to moderate trauma should not exclude such consideration.

Electroencephalogram, Circulation, and Lung Function After High-Velocity Behind Armor Blunt Trauma

Behind armor blunt trauma (BABT) is defined as the nonpenetrating injury resulting from a ballistic impact on personal body armor. The protective vest may impede the projectile, but some of the kinetic energy is transferred to the body, causing internal injuries and occasionally death. The aim in this study was to investigate changes in electroencephalogram (EEG) and physiologic parameters after high-velocity BABT. Eight anesthetized pigs, wearing body armor (including a ceramic plate) on the right side of their thorax, were shot with a 7.62-mm assault rifle (velocity approximately 800 m/s). The shots did not penetrate the armor and these animals were compared with control animals (n = 4), shot with blank ammunition. EEG and several physiologic parameters were thereafter monitored during a 2-hour period after the shot. All animals survived during the experimental period. Five of the exposed animals showed a temporary effect on EEG. Furthermore, exposed animals displayed decreased cardiac capacity and an impaired oxygenation of the blood. Postmortem examination revealed subcutaneous hematomas and crush injuries to the right lung. The results in our animal model indicate that high-velocity BABT induce circulatory and respiratory dysfunction, and in some cases even transient cerebral functional disturbances.

Detection of flail tricuspid valve many years after blunt chest trauma

Posttraumatic tricuspid insufficiency is a rare clinical entity that is mostly associated with traffic accidents causing nonpenetrating chest wall injury. Here we report a patient with a flail tricuspid valve detected many years after blunt chest trauma at work place.

Determinants of outcome of primary repair of colonic trauma

OBJECTIVES: To search of parameters for the selection of the group cases of colonic injuries getting maximum benefit of primary repair. STUDY DESIGN: A prospective non-randomized study. SETTING: Surgical Unit IV, DHQ Hospital, Faisalabad. SUBJECTS: Patients with colonic trauma due to penetrating and non-penetrating injuries. MAIN OUTCOME DETERMINANTS: The main outcome determinants found significant were age, proper prompt treatment, severity of injury, haemodynamic status at the time of operation and gross faecal contamination. RESULTS: Thirty patients colonic trauma who the basis of history, clinical examination and investigations. Patients were closely observed for sign and symptoms of anastomotic leak, and intra- record of these patients was maintained on preformed proforma. All risk factors were made measurable on abdominal sepsis, wound infection. Out of 30 patients, presented to Emergency Ward during one year, underwent exploratory laparotomy. The complete 24 patients were managed by primary repair and six patients were managed by staged procedure. All the 24 patients developed no infective complications. One out of six patients of staged procedure group died on 3rd post-operative day due to sudden myocardial infarction and three out of six patients developed infective complications. CONCLUSIONS: Age, proper prompt treatment, severity of injury, haemodynamic status at the time of operation and gross faecal contamination are determinants of outcome of primary repair of colonic trauma.

Occurrence and prognosis of nonpenetrating injuries in eyes with Verisyse iris-supported phakic intraocular lens

We report 8 cases of blunt trauma in patients with a Verisyse phakic intraocular lens (pIOL) (AMO). Two cases resulted in dislocation of the pIOL that required repositioning; the other 6 were managed conservatively. In all cases, the outcomes were satisfactory, with no further complications. The cases represent scenarios that patients and physicians might encounter postoperatively and describe ways to manage the complication.

Traumatic Tricuspid Insufficiency with Chordae Tendinae Rupture: A Case Report and Literature Review

With the increase in the number of automobile accidents, traumatic tricuspid insufficiency, a rare complication of non-penetrating blunt chest injury, has become an important problem. This kind of injury has been found more frequently during the last decade, partly because of better diagnostic procedures and a better understanding of the pathology. Here, we report a 22-year-old male patient who suffered chest trauma from an automobile accident. Echocardiography demonstrated tricuspid chordae tendinae rupture with remarkable tricuspid regurgitation. We discuss this case in comparison with the previous literature. This case reminds us that physicians in the emergency department should be aware of this potential complication following non-penetrating chest trauma.

Is Posttraumatic Epilepsy the Best Model of Posttraumatic Epilepsy?

A Model of Posttraumatic Epilepsy Induced by Lateral Fluid-Percussion Brain Injury in Rats Kharatishvili I, Nissinen JP, McIntosh TK, Pitkänen A Neuroscience 2006;140:685–697 Although traumatic brain injury is a major cause of symptomatic epilepsy, the mechanism by which it leads to recurrent seizures is unknown. An animal model of posttraumatic epilepsy that reliably reproduces the clinical sequelae of human traumatic brain injury is essential to identify the molecular and cellular substrates of posttraumatic epileptogenesis, and perform preclinical screening of new antiepileptogenic compounds. We studied the electrophysiologic, behavioral, and structural features of posttraumatic epilepsy induced by severe, non-penetrating lateral fluid-percussion brain injury in rats. Data from two independent experiments indicated that 43% to 50% of injured animals developed epilepsy, with a latency period between 7 weeks to 1 year. Mean seizure frequency was 0.3 ± 0.2 seizures per day and mean seizure duration was 113 ± 46 s. Behavioral seizure severity increased over time in the majority of animals. Secondarily generalized seizures comprised an average of 66 ± 37% of all seizures. Mossy fiber sprouting was increased in the ipsilateral hippocampus of animals with posttraumatic epilepsy compared with those subjected to traumatic brain injury without epilepsy. Stereologic cell counts indicated a loss of dentate hilar neurons ipsilaterally following traumatic brain injury. Our data suggest that posttraumatic epilepsy occurs with a frequency of 40% to 50% after severe non-penetrating fluid-percussion brain injury in rats, and that the lateral fluid percussion model can serve as a clinically relevant tool for pathophysiologic and preclinical studies.

Group A Streptococcal Myonecrosis: Increased Vimentin Expression after Skeletal‐Muscle Injury Mediates the Binding ofStreptococcus pyogenes

Necrotizing fasciitis and myonecrosis caused by invasive infection with group A streptococci (GAS) are life-threatening conditions that have reemerged worldwide. Half of all GAS myonecrosis cases have no known portal of entry; yet, for unknown reasons, infection becomes established precisely at the site of a prior, nonpenetrating minor injury, such as a muscle strain. We hypothesized that GAS establishes infection by binding to surface molecules that are up-regulated on injured skeletal-muscle cells. Here, we isolated and identified vimentin as the major skeletal-muscle GAS-binding protein. Furthermore, we found that vimentin expression was up-regulated on injured skeletal-muscle cells in vitro and was expressed in muscle tissues from a patient with GAS myonecrosis who died of streptococcal toxic shock syndrome. These findings provide a molecular mechanism to explain the development of severe GAS soft-tissue infections at the sites of prior minor muscle trauma. This understanding may provide a basis for novel preventive strategies or therapies for patients with this devastating infection.

Blast-Related Traumatic Brain Injury: What Is Known?

Blast-Related Traumatic Brain Injury: What Is Known?

Midfoot Coccidioidal Osteomyelitis: A Case Report and Review of the Literature

Coccidioides immitis is endemic in arid parts of the southwestern United States and regions of Central and South America. Symptomatic infection (comprising 40% of cases) initially presents as a flu-like illness with fever, cough, headache, rash, and myalgias. Some patients (especially those who are immunocompromised) fail to recover, with the development of chronic pulmonary infection or widespread disseminated infection1. A Coccidioides immitis infection that is disseminated to bone is very difficult to treat and usually requires lifetime suppressive antifungal therapy1-3. The present report describes a patient with recurrent osseous coccidioidal osteomyelitis at a new locus who presented after minor trauma to the middle part of the foot. The patient was managed successfully with surgical debridement and antifungal medication. The pathophysiology of osseous infection and treatment options are discussed. The patient was informed that data concerning this case would be submitted for publication. Six years prior to presentation, a thirty-nine-year-old man was diagnosed with disseminated coccidioidomycosis involving the thoracic vertebrae, skin, and lungs. The diagnosis was made on the basis of a biopsy of lung tissue. At the time of diagnosis, the Coccidioides complement fixation titer was 1:2048. The patient was managed with amphotericin B (total dose, 1.5 g) and high-dose fluconazole. Approximately eighteen months before admission, fluconazole was discontinued when the Coccidioides titers returned to normal (<1:2). Six months prior to presentation, the patient sustained a minor nonpenetrating injury that resulted in pain and tenderness in the lateral aspect of the right foot, with a recurrent nonhealing wound. The injury initially was thought to have resolved without treatment, but two months later another lesion recurred in the same region. Over the subsequent four months, the patient was seen at multiple clinics and was managed with several courses of antimicrobial medication, without healing of the …