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Gunshot wounds to the spine in post-Katrina New Orleans
Injury, Int. J. Care Injured 44 (2013) 1601–1606
Contents lists available at SciVerse ScienceDirect
Injury journal homepage: www.elsevier.com/locate/injury
Gunshot wounds to the spine in post-Katrina New Orleans Jayme Trahan a, Daniel Serban b, Gabriel C. Tender c,* a
Neurosurgery Program, Louisiana State University, New Orleans, LA, USA ‘‘Bagdasar-Arseni’’ Emergency Hospital, Bucharest, Romania c Louisiana State University, New Orleans, LA, USA b
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 20 June 2013
Background: Gunshot wounds (GSW) to the spine represent a major health concern within today’s society. Our study assessed the epidemiologic characteristics of patients with GSW to the spine treated in New Orleans. Patients and methods: A retrospective chart review was performed from January 2007 through November 2011 on all the patients who were seen in the emergency room and diagnosed with a gunshot wound to the spine. Epidemiologic factors, as well as the results of admission toxicology screening, were noted. Outcome analysis was performed on patients undergoing conservative versus operative management for their injuries. Clinical outcomes were assessed using the ASIA classification system. Complications related to initial injury, neurosurgical procedures, and hospital stay were noted. Results: A total of 147 patients were enrolled. Of those diagnosed with a GSW to the spine, 88 (59.8%) received an admission toxicology screen. Seventy-three (83%) patients out of those tested had a positive screen, with the most common substances detected being cannabis, cocaine, and alcohol. In regards to management, 127 (87%) patients were treated conservatively and only one (0.7%) patient improved clinically from ASIA D to E. Of the 20 patients who underwent surgery, one (5%) patient had clinical improvement post-operatively from ASIA C to D. Conclusions: This study evaluates the largest number of patients with GSW to the spine per year treated in a single centre, illustrating the violent nature of New Orleans. In this urban population, there was a clear correlation between drug use and suffering a GSW to the spine. Surgical intervention was seldom indicated in these patients and was predominately used for fixation of unstable fractures and decompression of compressive injuries, particularly below T11. Minimally invasive techniques were used successfully at our institution to minimize the risk of post-operative CSF leak. ß 2013 Elsevier Ltd. All rights reserved.
Keywords: Gunshot Spine Drugs Violence
Introduction Gunshot wounds (GSW) to the spine represent a major health concern within today’s modern society. This form of penetrating injury accounts for approximately 1200 (11%) of the 11,000 new cases of spinal column injury each year [1]. Due to the high likelihood of suffering severe neurological damage secondary to these wounds, there is a significant socioeconomic impact imparted by this subset of patients [4,20]. While the main cause of GSW varies with geographical location [31], within the urban setting in the USA, gang and drug-related violence far exceeds all other etiologies [19,22]. Furthermore, there
* Corresponding author at: 2020 Gravier Street, Suite 744, New Orleans, LA 70112, USA. Tel.: +1 504 568 6123; fax: +1 504 568 6127. E-mail addresses: [email protected], [email protected] (G.C. Tender). 0020–1383/$ – see front matter ß 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.injury.2013.06.021
is a direct association between drug-use and injury caused by interpersonal violence [7,10,11,24,25]. Previous studies conducted in New Orleans have described the association between substance use and traumatic injury within the urban population [24,25]. The goal of our study was to assess the epidemiologic characteristics of patients with GSW to the spine treated in New Orleans. Materials and methods A retrospective chart review was performed from January 2007 through November 2011. All patients who were evaluated in the emergency room and diagnosed with a new gunshot wound to the spinal axis were included in this study. A total of 147 patients met these criteria. Within the selected patient population, epidemiologic factors including age, gender, race, and marital status, as well as the results of admission toxicology screening, were noted. Outcome
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analysis was performed in patients with a positive versus negative toxicology screening, and patients undergoing conservative versus operative management for their injuries. The clinical outcome was assessed using the ASIA classification system. Complications related to initial injury, neurosurgical procedures, and hospital stay, were noted. Results Of the 147 patients included in the study, 123 (84%) were African Americans and 13 (9%) Caucasians. Eleven (7%) patients were not identified by race during the admission. The age ranged between 14 and 66 years old (mean: 27), with the mean age for African Americans being 25, while the mean age for Caucasians was 36. Ninety-two percent of the patients were male. In regards to marital status, 97% of the patients were single versus 3% married. Within the population included in the study, 88 (59.8%) patients received an admission toxicology screen. Seventy-three (83%) patients of those tested had positive results. Of those 73 patients that tested positive, 47 (64.3%) had multiple substances detected within their toxicology screen. Among the individual substances tested for, THC was by far the most common substance detected, with 58 (79.4%) patients having a positive result. Less common substances detected included cocaine (32.8%), ethanol (31.5%), benzodiazepine (30.1%), and opiates (27.3%) (Table 1). When assessing the frequency of GSW to the spine by specific levels affected, the cervical spine was injured in 40 (27%) patients. Of these patients, 19 (48%) suffered complete cord injury. The thoracic spine was injured in 53 (36%) patients with 35 (66%) suffering complete injury. The lumbo-sacral spine was affected in 54 (36%) patients with only 7 (13%) patients suffering complete injury. In regards to management, 127 (87%) patients were treated conservatively. Of those that were managed non-operatively, one (0.7%) patient improved clinically from ASIA D to E. Of the 20 patients who underwent surgery, 13 had procedures performed below T11 while 7 had procedures above T11. Of those patients who had surgery below T11, 9 patients underwent decompressive procedures with only 1 showing clinical improvement postoperatively from ASIA score C to D (Fig. 1). Six of these 9 patients had a minimally invasive approach, using sequential tubular Table 1 Patient demographics and toxicology results. Patient demographics Race African-American Caucasian Other Sex Male Female Age (mean years old) African-Americans Caucasians Marital status Single Married Toxicology Total patients tested = 88 Drug THC Cocaine Ethanol Benzodiazepine Opiates Amphetamine Methadone Multiple substances
Number (percent, %) 123 (84%) 13 (9%) 11 (7%) 135 (92%) 12 (8%) 27 25 36 142 (97%) 5 (3%) Total patients with (+) test = 73 (83%) 58 (79.4%) 24 (32.8%) 23 (31.5%) 22 (30.1%) 20 (27.3%) 5 (6.8%) 2 (2.7%) 47 (64.3%)
dilators to place the final tubular retractor through which the decompressive laminectomy and bullet removal was performed. The remaining patients underwent stabilization procedures for treatment of unstable fractures. There were 6 procedures performed on the cervical spine and 4 for the treatment of unstable fractures. Two underwent decompressive procedures, one for persistent radiculopathy (Fig. 2) and another to treat a developing cord infarction (Fig. 3). One patient underwent a thoracic stabilization procedure. None of the patients who underwent surgery for lesions above T11 showed improvement in ASIA scores post-operatively (Table 2). There were 41 patients within the study population that experienced complications secondary to their underlying injury and subsequent hospitalization. There were 3 patients which experienced complications related directly to their neurosurgical procedure; 2 wound infections and 1 intra-operative durotomy. Within our patient population, mortality rate was 7% (10 patients) during the hospitalization (Table 3). Discussion This study evaluates the largest number of patients with GSW to the spine per year treated in a single centre, illustrating the violent nature of the city of New Orleans [3,6,17,18,32,36]. Moreover, to our knowledge, this is the first study to evaluate the epidemiologic variables associated with GSW to the spine and, specifically, the positive toxicology screening upon admission. As previously noted, 83% of those patients suffering GSW to the spine who were tested had positive toxicology. While THC was the most frequently abused substance, it is perplexing that cocaine was detected more frequently than alcohol in the blood of GSW trauma victims. Previous authors have assessed drug use in adolescent trauma patients prior to the onset of Hurricane Katrina. Their findings revealed that 64% of patients seen at Charity Hospital for traumatic injuries tested positive for either illicit drugs or alcohol and that there was a strong association between GSW to the body and a positive toxicology screening [24]. In a separate study, the same author found 80% of those patients admitted after suffering intentional trauma had positive toxicology screening compared to 63% of patients who suffered accidental trauma [25]. It is apparent that, despite the large population shifts associated with the city’s complete evacuation and re-inhabiting after Hurricane Katrina, the association between substance abuse and intentional trauma has persisted. In regards to other epidemiologic variables within our patient population, the overwhelming majority of patients were single minority males with an average age of 25. These findings are consistent with previously published reports describing the prevalence of interpersonal violence among young urban minority groups [8,14]. The kinetics of GSW to the spine has its most devastating impact on the segments of the spinal column that contain cord. Consistent with previous publications, the patients in our study experiencing GSW to the cervical and thoracic spine suffered complete injuries (ASIA A) in 48% and 66% of the cases, respectively [40]. Conversely, GSW to the lumbar spine caused only 12% of its victims to suffer a complete injury. The energy of any moving object is determined according to the formula E = 1/2 mv2, where E = kinetic energy, m = mass, and v = velocity. Therefore, the bullet energy impacted to tissues increases exponentially with the velocity. Most civilian firearms (typically pistols and handguns) have muzzle velocities of less than 2000 ft/s and are considered ‘‘low energy’’, whereas military assault rifles (like AK-47 and M-16) have muzzle velocities greater than 2000 ft/s and are considered ‘‘high energy’’. The closer the range of a gunshot, the less energy will be lost during transit and
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Fig. 1. Three patients with gunshot wounds below T11 (L3, L1, and L2, respectively) and mixed neurological deficit (ASIA C, A, and A, respectively). These patients underwent a minimally invasive laminectomy for canal decompression and bullet removal via a 22 mm tubular retractor. None of the patients experienced postoperative CSF fistulas or infections. Only the incomplete patient improved from ASIA C to ASIA D.
thus the more energy will be transferred to the victim. Fragmentation of the bullet on impact (as in hollow-point bullets) results in multiple trajectories and increased damage to the tissues. The spinal cord lesions can thus be due to direct damage, or indirect injury from the shock wave and/or from arterial vasospasm leading to spinal cord ischaemia. Because of the severity of irreversible damage from the primary insult imparted on the neural structures at the time of the GSW, surgical intervention offers little benefit for neurologic recovery. Of the 127 patients managed conservatively, only 1 (0.7%) improved neurologically. Similarly, of the 20 patients who underwent an operative intervention, only 1 (5%) improved clinically. Because of this ineffectiveness to reverse the primary injury caused by GSW, surgical intervention is rarely required.
Clear operative indications in GSW to the spine are limited to spinal instability, progressive neurologic deterioration, and CSF fistula [5,15]. Of the 147 patients included in our study, only 20 (13%) patients required spinal operative intervention, of which 9 (45%) had spinal stabilization procedures alone, whereas 11 (55%) underwent spinal decompression procedures with or without stabilization. Spinal instability should be suspected in patients with comminuted fractures involving the anterior and posterior elements, particularly if associated with abnormal focal angulation or subluxation. Progressive angulation over the course of weeks or months can also be interpreted as instability. Occasionally, MRI can identify the degree of ligamentous injury and indirectly assist in the determination of the degree of instability.
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Fig. 2. Gunshot wounds to the cervical spine through the right vertebral foramen causing canal stenosis and radiculopathy. The patient underwent decompressive laminectomy and fusion without neurologic recovery.
In patients with incomplete neurologic deficit, spine surgeons may choose to treat a potentially unstable fracture that may result in a worsening neurological status if not surgically stabilized. This is particularly true for patients with retained bullet or bone fragments in the spinal canal, who can also undergo a surgical decompression at the same time. In patients with complete neurologic deficit, the surgical goal is to provide sufficient spinal stability to allow the patient to undergo the strenuous, but necessary, physical therapy and re-training to use their preserved motor function to accommodate to the daily needs, in the rehabilitation facilities. The surgical approach typically involves instrumentation and depends on the particular configuration of the fracture. Unstable GSW involving mostly the vertebral body can be addressed by performing a corpectomy and fixation, whereas those involving predominantly the posterior elements are treated by a posterior multilevel fixation, with or without decompression. Occasionally, in severely comminuted fractures, a circumferential fixation is required. Within our review, 40 patients suffered GSW to the cervical spine, 34 (85%) of which were managed conservatively. Of the 6 operative patients, 4 underwent operative stabilization of fractures and 2 underwent decompressive procedures: one for removal of a projectile causing radiculopathy and another for decompression of an expanding contusion. Neither of the patients undergoing
decompression exhibited any clinical improvement post-operatively. Unfortunately, these outcomes are not uncommon for penetrating injuries to the cervical spine [5,38]. In regards to conservative management strategies, several controversies exist. The use of high dose corticosteroids in the acute setting has been extensively evaluated for its potential to reduce swelling and preserve function. Current literature does not support this use [9,12,13,21,26]. Another controversy lies in the use of c-collar immobilization following injury. Current evidence does not support the use of cervical immobilization prior to securing the airway within the hospital setting [2,16]. The thoracic spine is the most often injured segment of the spinal axis. It is also the most severely affected when injured [39]. In our patient population, 53 (36%) patients suffered GSW to the thoracic spine, with 35 (66%) of these people suffering a complete cord injury. Only one patient met the criteria for spinal stabilization. No patients in this group had recovery of neurologic function after the initial injury. The lumbo-sacral spine was injured in 54 patients with only 13% suffering complete injury. One (11%) of 9 patients who underwent operative decompression of their injury showed improvement from ASIA score C to D. Several considerations need to be made when evaluating injuries at this level. First, the role of operative decompression of incomplete injuries after GSW to the lumbar spine is controversial. Multiple authors have shown clinical
Fig. 3. Gunshot wounds to the thoracic spine, presenting with T4 paraplegia. Two days later, the patient developed quadriparesis and ascending sensory exam. Magnetic resonance imaging showed extensive oedema in the cervical spinal cord. A decompressive cervical laminectomy and fusion was performed without recovery of neurologic function.
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Table 2 Patients’ level of injury, degree of injury, and surgical treatment. Clinical data Level affected
Cervical Thoracic Lumbo-sacral
No. of patients
Degree of injury
40 53 54
Incomplete
Decompression
Stabilization
19 35 7
21 18 47
2 0 9
4 1 4
benefit to removal of bullet fragments causing stenosis at T12 or below [26,38]. Cybulski et al. noted improvements in clinical exams as high as 48% when decompressing the lumbar spine after GSW injury [6]. Conversely, other series have not been able to show benefit to decompressive procedures [28,36]. Our series has only shown a modest 11% chance for recovery of function. Second, if operative intervention is decided as the best course of action, it does not need to be emergent to see benefit in a neurologically stable patient. Cybulski et al. showed there is no difference between the improvements in ASIA scores when comparing patients decompressed within 72 h of injury and those decompressed after 72 h of injury [6]. Therefore, systemic stabilization and treatment of more urgent injuries should hold precedence in a neurologically stable patient. Third, the trajectory of the ballistic fragments must be determined as the potential for infection exists if the colon is perforated prior to entrance of the ballistic into the spinal column [17,26,27]. In this case, prophylactic antibiotic coverage of gram positive, gram negative, and anaerobic organisms for a minimum of 7–14 days is recommended [17,26]. The literature does not support retrieval of the ballistic fragment in the absence of a known infection related to colonic perforation [17,23,29,38]. In our review, 2 patients had post-operative wound infections related to decompressive procedures. Interestingly, both patients had suffered colonic perforation at the time of their GSW to the spine, which likely led to an increased operative risk despite appropriate antibiotic coverage. Both patients were taken back to the operating room for wound wash-out and placement of woundvac, which eventually allowed for wound healing by secondary intention. Another indication for surgical intervention related to GSW to the spine is persistent CSF leak. If a CSF leak is noted, superficial debridement of tract should be performed followed by placement of a lumbar drain. If lumbar drainage does not resolve the leak, then a formal open surgery is required for identification and closure of the dural defect [5,29,30]. Fortunately, no patients in our series had noted CSF leaks related to their GSW injury.
Table 3 Complications. Complications General Pneumonia Sacral decubitus Hepato-biliary Cardiac arrest DVT/PE Pulmonary effusion Other Operative Wound infection Durotomy Deaths Cardiac arrest Brain death C1 Transection Pulmonary embolism
Number (percent,%) 12 6 5 4 3 3 8
(8.1%) (4.0%) (3.4%) (2.7%) (2.0%) (2.0%) (5.4%)
2 (10%) 1 (5%) 4 3 2 1
Procedure
Complete
(2.7%) (2.0%) (1.3%) (0.6%)
CSF leaks can also occur postoperatively, after removal of a bullet fragment, whether the dura mater was damaged by the initial injury or by the attempts to mobilize and remove the fragment. We have successfully used a minimally invasive approach to decrease the risk of postoperative CSF leaks. The one intraoperative durotomy occurred while removing a bullet fragment from the L1-2 foramen; the dural tear was covered with dural sealant without direct dural repair, and, after removing the tubular retractor, the paraspinous muscles further sealed the communication between the spine and skin, thus no CSF leak was observed postoperatively. Several potential complications exist related to GSW to the spine. CSF fistulas and infections related to colonic perforation have been previously addressed. The potential for lead toxicity exists; however, this is extremely uncommon. Bullet lodgment in the disc space appears to increase this risk as compared to a projectile within the CSF circulation because synovial fluid is a stronger solvent than CSF. Lead levels can be drawn if this complication is expected [5]. Another potential complication, also rare, is bullet migration. There has been much debate over Magnetic Resonance Imaging (MRI) and its potential to cause ballistic movement within the body. The MRI is rarely needed for the area involved with the GSW; however, these patients sometimes have multiple injuries and may require an MRI of a different body part (e.g., the cervical spine for clearance). Despite initial concerns over the inability to classify the ferromagnetic properties of the many projectile types, studies have since shown that ballistic fragments from GSW can safely be exposed to MRI scans [33,34,37]. Despite this, the topic remains controversial and is usually handled on a patient-by-patient basis at our institution. Finally, GSW to the spine has the potential to cause chronic neuropathic pain. This most frequently occurs with injuries to the conus medullaris and cauda equina regions [35]. Unfortunately, reduction in pain is usually not associated with bullet removal and other methods to treat the chronic pain have variable efficacy [38]. Death is the ultimate complication associated with GSW, although it is rarely related to the injury suffered by the spine GSW. The potential does exist, however, for injuries to the craniocervical junction, as this area controls the respiratory drive. In our series, 10 (6.8%) patients succumb to their injuries during their hospitalization, with 2 (1.3%) of these patients suffering injuries to cord at the C1 level, while the remaining 8 patients died from injuries to other organ systems.
Conclusion The incidence of GSW to the spine in New Orleans is over three times higher than that in the next most violent city. In this urban population, there was a clear correlation between drug use and suffering a GSW to the spine injury. Surgical intervention was seldomly used in these patients and included decompressive procedures in patients with incomplete neurological deficit and compressive pathology, particularly below T11, and instrumented stabilization procedures in patients with unstable fractures. For
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decompression and bullet removal procedures, minimally invasive techniques eliminated the risk of postoperative CSF fistula. Conflict of interest The authors declare that they have no conflict of interest. References [1] Spinal cord injury facts and figures at a glance. Journal of Spinal Cord Medicine 2004;27(Suppl. 1):S139–40. [2] Arishita GI, Vayer JS, Bellamy RF. Cervical spine immobilization of penetrating neck wounds in a hostile environment. Journal of Trauma 1989;29:332–7. [3] Benzel EC, Hadden TA, Coleman JE. Civilian gunshot wounds to the spinal cord and cauda equina. Neurosurgery 1987;20:281–5. [4] Bishop M, Shoemaker WC, Avakian S, et al. Evaluation of a comprehensive algorithm for blunt and penetrating thoracic and abdominal trauma. American Surgeon 1991;57:737–46. [5] Bono CM, Heary RF. Gunshot wounds to the spine. Spine Journal 2004;4:230– 40. [6] Cybulski GR, Stone JL, Kant R. Outcome of laminectomy for civilian gunshot injuries of the terminal spinal cord and cauda equina: review of 88 cases. Neurosurgery 1989;24:392–7. [7] Darke S. The toxicology of homicide offenders and victims: a review. Drug and Alcohol Review 2010;29:202–15. [8] Farmer JC, Vaccaro AR, Balderston RA, et al. The changing nature of admissions to a spinal cord injury center: violence on the rise. Journal of Spinal Disorders 1998;11:400–3. [9] Fehlings MG. Editorial: recommendations regarding the use of methylprednisolone in acute spinal cord injury: making sense out of the controversy. Spine (Phila Pa 1976) 2001;26:S56–7. [10] Galea S, Ahern J, Tardiff K, et al. Drugs and firearm deaths in New York City, 1990–1998. Journal of Urban Health 2002;79:70–86. [11] Gill JR, Lenz KA, Amolat MJ. Gunshot fatalities in children and adolescents in New York City. Journal of Forensic Sciences 2003;48:832–5. [12] Heary RF, Vaccaro AR, Mesa JJ, Balderston RA. Thoracolumbar infections in penetrating injuries to the spine. Orthopedic Clinics of North America 1996;27:69–81. [13] Heary RF, Vaccaro AR, Mesa JJ, et al. Steroids and gunshot wounds to the spine. Neurosurgery 1997;41:576–83 [discussion 83–84]. [14] Isiklar ZU, Lindsey RW. Gunshot wounds to the spine. Injury 1998;29(Suppl. 1). SA7-12. [15] Kahraman S, Gonul E, Kayali H, et al. Retrospective analysis of spinal missile injuries. Neurosurgical Review 2004;27:42–5. [16] Kaups KL, Davis JW. Patients with gunshot wounds to the head do not require cervical spine immobilization and evaluation. Journal of Trauma 1998;44:865–7. [17] Kihtir T, Ivatury RR, Simon R, Stahl WM. Management of transperitoneal gunshot wounds of the spine. Journal of Trauma 1991;31:1579–83. [18] Klein Y, Cohn SM, Soffer D, et al. Spine injuries are common among asymptomatic patients after gunshot wounds. Journal of Trauma 2005;58:833–6.
[19] Krieger MDLM, Apuzzo MLJ. Epidemiology of penetrating craniocerebral injuries in the urban setting. Neurosurgery Clinics of North America 1995;6:605–10. [20] Kupcha PC, An HS, Cotler JM. Gunshot wounds to the cervical spine. Spine (Phila Pa 1976) 1990;15:1058–63. [21] Levy ML, Gans W, Wijesinghe HS, et al. Use of methylprednisolone as an adjunct in the management of patients with penetrating spinal cord injury: outcome analysis. Neurosurgery 1996;39:1141–8 [discussion 48–49]. [22] Levy ML, Masri LS, Levy KM, et al. Penetrating craniocerebral injury resultant from gunshot wounds: gang-related injury in children and adolescents. Neurosurgery 1993;33:1018–24 [discussion 24–5]. [23] Lin SS, Vaccaro AR, Reisch S, et al. Low-velocity gunshot wounds to the spine with an associated transperitoneal injury. Journal of Spinal Disorders 1995;8:136–44. [24] Madan A, Beech DJ, Flint L. Drugs, guns, and kids: the association between substance use and injury caused by interpersonal violence. Journal of Pediatric Surgery 2001;36:440–2. [25] Madan AK, Yu K, Beech DJ. Alcohol and drug use in victims of life-threatening trauma. Journal of Trauma 1999;47:568–71. [26] Moon E, Kondrashov D, Hannibal M, et al. Gunshot wounds to the spine: literature review and report on a migratory intrathecal bullet. American Journal of Orthopedics (Belle Mead NJ) 2008;37:E47–51. [27] Quigley KJ, Place HM. The role of debridement and antibiotics in gunshot wounds to the spine. Journal of Trauma 2006;60:814–9 [discussion 19–20]. [28] Robertson DP, Simpson RK. Penetrating injuries restricted to the cauda equina: a retrospective review. Neurosurgery 1992;31:265–9 [discussion 69–70]. [29] Roffi RP, Waters RL, Adkins RH. Gunshot wounds to the spine associated with a perforated viscus. Spine (Phila Pa 1976) 1989;14:808–11. [30] Romanick PC, Smith TK, Kopaniky DR, Oldfield D. Infection about the spine associated with low-velocity-missile injury to the abdomen. Journal of Bone and Joint Surgery 1985;67:1195–201. [31] Rosenfeld JV. Gunshot injury to the head and spine. Journal of Clinical Neuroscience 2002;9:9–16. [32] Simpson Jr RK, Venger BH, Narayan RK. Treatment of acute penetrating injuries of the spine: a retrospective analysis. Journal of Trauma 1989;29:42–6. [33] Smith AS, Hurst GC, Duerk JL, Diaz PJ. MR of ballistic materials: imaging artifacts and potential hazards. American Journal of Neuroradiology 1991;12:567–72. [34] Smugar SS, Schweitzer ME, Hume E. MRI in patients with intraspinal bullets. Journal of Magnetic Resonance Imaging 1999;9:151–3. [35] Spaic M, Petkovic S, Tadic R, Minic L. DREZ surgery on conus medullaris (after failed implantation of vascular omental graft) for treating chronic pain due to spine (gunshot) injuries. Acta Neurochirurgica 1999;141:1309–12. [36] Stauffer ES, Wood RW, Kelly EG. Gunshot wounds of the spine: the effects of laminectomy. Journal of Bone and Joint Surgery 1979;61:389–92. [37] Teitelbaum GP, Yee CA, Van Horn DD, et al. Metallic ballistic fragments: MR imaging safety and artifacts. Radiology 1990;175:855–9. [38] Waters RL, Adkins RH. The effects of removal of bullet fragments retained in the spinal canal. A collaborative study by the National Spinal Cord Injury Model Systems. Spine (Phila Pa 1976) 1991;16:934–9. [39] Waters RL, Adkins RH, Yakura J, Sie I. Profiles of spinal cord injury and recovery after gunshot injury. Clinical Orthopaedics and Related Research 1991;14–21. [40] Young JBP, Bowen A. Spinal cord injury statistics: experience of the regional spinal cord injury systems. Phoenix Good Samaritan Medical Center 1982; 1–152.
Contents lists available at SciVerse ScienceDirect
Injury journal homepage: www.elsevier.com/locate/injury
Gunshot wounds to the spine in post-Katrina New Orleans Jayme Trahan a, Daniel Serban b, Gabriel C. Tender c,* a
Neurosurgery Program, Louisiana State University, New Orleans, LA, USA ‘‘Bagdasar-Arseni’’ Emergency Hospital, Bucharest, Romania c Louisiana State University, New Orleans, LA, USA b
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 20 June 2013
Background: Gunshot wounds (GSW) to the spine represent a major health concern within today’s society. Our study assessed the epidemiologic characteristics of patients with GSW to the spine treated in New Orleans. Patients and methods: A retrospective chart review was performed from January 2007 through November 2011 on all the patients who were seen in the emergency room and diagnosed with a gunshot wound to the spine. Epidemiologic factors, as well as the results of admission toxicology screening, were noted. Outcome analysis was performed on patients undergoing conservative versus operative management for their injuries. Clinical outcomes were assessed using the ASIA classification system. Complications related to initial injury, neurosurgical procedures, and hospital stay were noted. Results: A total of 147 patients were enrolled. Of those diagnosed with a GSW to the spine, 88 (59.8%) received an admission toxicology screen. Seventy-three (83%) patients out of those tested had a positive screen, with the most common substances detected being cannabis, cocaine, and alcohol. In regards to management, 127 (87%) patients were treated conservatively and only one (0.7%) patient improved clinically from ASIA D to E. Of the 20 patients who underwent surgery, one (5%) patient had clinical improvement post-operatively from ASIA C to D. Conclusions: This study evaluates the largest number of patients with GSW to the spine per year treated in a single centre, illustrating the violent nature of New Orleans. In this urban population, there was a clear correlation between drug use and suffering a GSW to the spine. Surgical intervention was seldom indicated in these patients and was predominately used for fixation of unstable fractures and decompression of compressive injuries, particularly below T11. Minimally invasive techniques were used successfully at our institution to minimize the risk of post-operative CSF leak. ß 2013 Elsevier Ltd. All rights reserved.
Keywords: Gunshot Spine Drugs Violence
Introduction Gunshot wounds (GSW) to the spine represent a major health concern within today’s modern society. This form of penetrating injury accounts for approximately 1200 (11%) of the 11,000 new cases of spinal column injury each year [1]. Due to the high likelihood of suffering severe neurological damage secondary to these wounds, there is a significant socioeconomic impact imparted by this subset of patients [4,20]. While the main cause of GSW varies with geographical location [31], within the urban setting in the USA, gang and drug-related violence far exceeds all other etiologies [19,22]. Furthermore, there
* Corresponding author at: 2020 Gravier Street, Suite 744, New Orleans, LA 70112, USA. Tel.: +1 504 568 6123; fax: +1 504 568 6127. E-mail addresses: [email protected], [email protected] (G.C. Tender). 0020–1383/$ – see front matter ß 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.injury.2013.06.021
is a direct association between drug-use and injury caused by interpersonal violence [7,10,11,24,25]. Previous studies conducted in New Orleans have described the association between substance use and traumatic injury within the urban population [24,25]. The goal of our study was to assess the epidemiologic characteristics of patients with GSW to the spine treated in New Orleans. Materials and methods A retrospective chart review was performed from January 2007 through November 2011. All patients who were evaluated in the emergency room and diagnosed with a new gunshot wound to the spinal axis were included in this study. A total of 147 patients met these criteria. Within the selected patient population, epidemiologic factors including age, gender, race, and marital status, as well as the results of admission toxicology screening, were noted. Outcome
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analysis was performed in patients with a positive versus negative toxicology screening, and patients undergoing conservative versus operative management for their injuries. The clinical outcome was assessed using the ASIA classification system. Complications related to initial injury, neurosurgical procedures, and hospital stay, were noted. Results Of the 147 patients included in the study, 123 (84%) were African Americans and 13 (9%) Caucasians. Eleven (7%) patients were not identified by race during the admission. The age ranged between 14 and 66 years old (mean: 27), with the mean age for African Americans being 25, while the mean age for Caucasians was 36. Ninety-two percent of the patients were male. In regards to marital status, 97% of the patients were single versus 3% married. Within the population included in the study, 88 (59.8%) patients received an admission toxicology screen. Seventy-three (83%) patients of those tested had positive results. Of those 73 patients that tested positive, 47 (64.3%) had multiple substances detected within their toxicology screen. Among the individual substances tested for, THC was by far the most common substance detected, with 58 (79.4%) patients having a positive result. Less common substances detected included cocaine (32.8%), ethanol (31.5%), benzodiazepine (30.1%), and opiates (27.3%) (Table 1). When assessing the frequency of GSW to the spine by specific levels affected, the cervical spine was injured in 40 (27%) patients. Of these patients, 19 (48%) suffered complete cord injury. The thoracic spine was injured in 53 (36%) patients with 35 (66%) suffering complete injury. The lumbo-sacral spine was affected in 54 (36%) patients with only 7 (13%) patients suffering complete injury. In regards to management, 127 (87%) patients were treated conservatively. Of those that were managed non-operatively, one (0.7%) patient improved clinically from ASIA D to E. Of the 20 patients who underwent surgery, 13 had procedures performed below T11 while 7 had procedures above T11. Of those patients who had surgery below T11, 9 patients underwent decompressive procedures with only 1 showing clinical improvement postoperatively from ASIA score C to D (Fig. 1). Six of these 9 patients had a minimally invasive approach, using sequential tubular Table 1 Patient demographics and toxicology results. Patient demographics Race African-American Caucasian Other Sex Male Female Age (mean years old) African-Americans Caucasians Marital status Single Married Toxicology Total patients tested = 88 Drug THC Cocaine Ethanol Benzodiazepine Opiates Amphetamine Methadone Multiple substances
Number (percent, %) 123 (84%) 13 (9%) 11 (7%) 135 (92%) 12 (8%) 27 25 36 142 (97%) 5 (3%) Total patients with (+) test = 73 (83%) 58 (79.4%) 24 (32.8%) 23 (31.5%) 22 (30.1%) 20 (27.3%) 5 (6.8%) 2 (2.7%) 47 (64.3%)
dilators to place the final tubular retractor through which the decompressive laminectomy and bullet removal was performed. The remaining patients underwent stabilization procedures for treatment of unstable fractures. There were 6 procedures performed on the cervical spine and 4 for the treatment of unstable fractures. Two underwent decompressive procedures, one for persistent radiculopathy (Fig. 2) and another to treat a developing cord infarction (Fig. 3). One patient underwent a thoracic stabilization procedure. None of the patients who underwent surgery for lesions above T11 showed improvement in ASIA scores post-operatively (Table 2). There were 41 patients within the study population that experienced complications secondary to their underlying injury and subsequent hospitalization. There were 3 patients which experienced complications related directly to their neurosurgical procedure; 2 wound infections and 1 intra-operative durotomy. Within our patient population, mortality rate was 7% (10 patients) during the hospitalization (Table 3). Discussion This study evaluates the largest number of patients with GSW to the spine per year treated in a single centre, illustrating the violent nature of the city of New Orleans [3,6,17,18,32,36]. Moreover, to our knowledge, this is the first study to evaluate the epidemiologic variables associated with GSW to the spine and, specifically, the positive toxicology screening upon admission. As previously noted, 83% of those patients suffering GSW to the spine who were tested had positive toxicology. While THC was the most frequently abused substance, it is perplexing that cocaine was detected more frequently than alcohol in the blood of GSW trauma victims. Previous authors have assessed drug use in adolescent trauma patients prior to the onset of Hurricane Katrina. Their findings revealed that 64% of patients seen at Charity Hospital for traumatic injuries tested positive for either illicit drugs or alcohol and that there was a strong association between GSW to the body and a positive toxicology screening [24]. In a separate study, the same author found 80% of those patients admitted after suffering intentional trauma had positive toxicology screening compared to 63% of patients who suffered accidental trauma [25]. It is apparent that, despite the large population shifts associated with the city’s complete evacuation and re-inhabiting after Hurricane Katrina, the association between substance abuse and intentional trauma has persisted. In regards to other epidemiologic variables within our patient population, the overwhelming majority of patients were single minority males with an average age of 25. These findings are consistent with previously published reports describing the prevalence of interpersonal violence among young urban minority groups [8,14]. The kinetics of GSW to the spine has its most devastating impact on the segments of the spinal column that contain cord. Consistent with previous publications, the patients in our study experiencing GSW to the cervical and thoracic spine suffered complete injuries (ASIA A) in 48% and 66% of the cases, respectively [40]. Conversely, GSW to the lumbar spine caused only 12% of its victims to suffer a complete injury. The energy of any moving object is determined according to the formula E = 1/2 mv2, where E = kinetic energy, m = mass, and v = velocity. Therefore, the bullet energy impacted to tissues increases exponentially with the velocity. Most civilian firearms (typically pistols and handguns) have muzzle velocities of less than 2000 ft/s and are considered ‘‘low energy’’, whereas military assault rifles (like AK-47 and M-16) have muzzle velocities greater than 2000 ft/s and are considered ‘‘high energy’’. The closer the range of a gunshot, the less energy will be lost during transit and
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Fig. 1. Three patients with gunshot wounds below T11 (L3, L1, and L2, respectively) and mixed neurological deficit (ASIA C, A, and A, respectively). These patients underwent a minimally invasive laminectomy for canal decompression and bullet removal via a 22 mm tubular retractor. None of the patients experienced postoperative CSF fistulas or infections. Only the incomplete patient improved from ASIA C to ASIA D.
thus the more energy will be transferred to the victim. Fragmentation of the bullet on impact (as in hollow-point bullets) results in multiple trajectories and increased damage to the tissues. The spinal cord lesions can thus be due to direct damage, or indirect injury from the shock wave and/or from arterial vasospasm leading to spinal cord ischaemia. Because of the severity of irreversible damage from the primary insult imparted on the neural structures at the time of the GSW, surgical intervention offers little benefit for neurologic recovery. Of the 127 patients managed conservatively, only 1 (0.7%) improved neurologically. Similarly, of the 20 patients who underwent an operative intervention, only 1 (5%) improved clinically. Because of this ineffectiveness to reverse the primary injury caused by GSW, surgical intervention is rarely required.
Clear operative indications in GSW to the spine are limited to spinal instability, progressive neurologic deterioration, and CSF fistula [5,15]. Of the 147 patients included in our study, only 20 (13%) patients required spinal operative intervention, of which 9 (45%) had spinal stabilization procedures alone, whereas 11 (55%) underwent spinal decompression procedures with or without stabilization. Spinal instability should be suspected in patients with comminuted fractures involving the anterior and posterior elements, particularly if associated with abnormal focal angulation or subluxation. Progressive angulation over the course of weeks or months can also be interpreted as instability. Occasionally, MRI can identify the degree of ligamentous injury and indirectly assist in the determination of the degree of instability.
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Fig. 2. Gunshot wounds to the cervical spine through the right vertebral foramen causing canal stenosis and radiculopathy. The patient underwent decompressive laminectomy and fusion without neurologic recovery.
In patients with incomplete neurologic deficit, spine surgeons may choose to treat a potentially unstable fracture that may result in a worsening neurological status if not surgically stabilized. This is particularly true for patients with retained bullet or bone fragments in the spinal canal, who can also undergo a surgical decompression at the same time. In patients with complete neurologic deficit, the surgical goal is to provide sufficient spinal stability to allow the patient to undergo the strenuous, but necessary, physical therapy and re-training to use their preserved motor function to accommodate to the daily needs, in the rehabilitation facilities. The surgical approach typically involves instrumentation and depends on the particular configuration of the fracture. Unstable GSW involving mostly the vertebral body can be addressed by performing a corpectomy and fixation, whereas those involving predominantly the posterior elements are treated by a posterior multilevel fixation, with or without decompression. Occasionally, in severely comminuted fractures, a circumferential fixation is required. Within our review, 40 patients suffered GSW to the cervical spine, 34 (85%) of which were managed conservatively. Of the 6 operative patients, 4 underwent operative stabilization of fractures and 2 underwent decompressive procedures: one for removal of a projectile causing radiculopathy and another for decompression of an expanding contusion. Neither of the patients undergoing
decompression exhibited any clinical improvement post-operatively. Unfortunately, these outcomes are not uncommon for penetrating injuries to the cervical spine [5,38]. In regards to conservative management strategies, several controversies exist. The use of high dose corticosteroids in the acute setting has been extensively evaluated for its potential to reduce swelling and preserve function. Current literature does not support this use [9,12,13,21,26]. Another controversy lies in the use of c-collar immobilization following injury. Current evidence does not support the use of cervical immobilization prior to securing the airway within the hospital setting [2,16]. The thoracic spine is the most often injured segment of the spinal axis. It is also the most severely affected when injured [39]. In our patient population, 53 (36%) patients suffered GSW to the thoracic spine, with 35 (66%) of these people suffering a complete cord injury. Only one patient met the criteria for spinal stabilization. No patients in this group had recovery of neurologic function after the initial injury. The lumbo-sacral spine was injured in 54 patients with only 13% suffering complete injury. One (11%) of 9 patients who underwent operative decompression of their injury showed improvement from ASIA score C to D. Several considerations need to be made when evaluating injuries at this level. First, the role of operative decompression of incomplete injuries after GSW to the lumbar spine is controversial. Multiple authors have shown clinical
Fig. 3. Gunshot wounds to the thoracic spine, presenting with T4 paraplegia. Two days later, the patient developed quadriparesis and ascending sensory exam. Magnetic resonance imaging showed extensive oedema in the cervical spinal cord. A decompressive cervical laminectomy and fusion was performed without recovery of neurologic function.
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Table 2 Patients’ level of injury, degree of injury, and surgical treatment. Clinical data Level affected
Cervical Thoracic Lumbo-sacral
No. of patients
Degree of injury
40 53 54
Incomplete
Decompression
Stabilization
19 35 7
21 18 47
2 0 9
4 1 4
benefit to removal of bullet fragments causing stenosis at T12 or below [26,38]. Cybulski et al. noted improvements in clinical exams as high as 48% when decompressing the lumbar spine after GSW injury [6]. Conversely, other series have not been able to show benefit to decompressive procedures [28,36]. Our series has only shown a modest 11% chance for recovery of function. Second, if operative intervention is decided as the best course of action, it does not need to be emergent to see benefit in a neurologically stable patient. Cybulski et al. showed there is no difference between the improvements in ASIA scores when comparing patients decompressed within 72 h of injury and those decompressed after 72 h of injury [6]. Therefore, systemic stabilization and treatment of more urgent injuries should hold precedence in a neurologically stable patient. Third, the trajectory of the ballistic fragments must be determined as the potential for infection exists if the colon is perforated prior to entrance of the ballistic into the spinal column [17,26,27]. In this case, prophylactic antibiotic coverage of gram positive, gram negative, and anaerobic organisms for a minimum of 7–14 days is recommended [17,26]. The literature does not support retrieval of the ballistic fragment in the absence of a known infection related to colonic perforation [17,23,29,38]. In our review, 2 patients had post-operative wound infections related to decompressive procedures. Interestingly, both patients had suffered colonic perforation at the time of their GSW to the spine, which likely led to an increased operative risk despite appropriate antibiotic coverage. Both patients were taken back to the operating room for wound wash-out and placement of woundvac, which eventually allowed for wound healing by secondary intention. Another indication for surgical intervention related to GSW to the spine is persistent CSF leak. If a CSF leak is noted, superficial debridement of tract should be performed followed by placement of a lumbar drain. If lumbar drainage does not resolve the leak, then a formal open surgery is required for identification and closure of the dural defect [5,29,30]. Fortunately, no patients in our series had noted CSF leaks related to their GSW injury.
Table 3 Complications. Complications General Pneumonia Sacral decubitus Hepato-biliary Cardiac arrest DVT/PE Pulmonary effusion Other Operative Wound infection Durotomy Deaths Cardiac arrest Brain death C1 Transection Pulmonary embolism
Number (percent,%) 12 6 5 4 3 3 8
(8.1%) (4.0%) (3.4%) (2.7%) (2.0%) (2.0%) (5.4%)
2 (10%) 1 (5%) 4 3 2 1
Procedure
Complete
(2.7%) (2.0%) (1.3%) (0.6%)
CSF leaks can also occur postoperatively, after removal of a bullet fragment, whether the dura mater was damaged by the initial injury or by the attempts to mobilize and remove the fragment. We have successfully used a minimally invasive approach to decrease the risk of postoperative CSF leaks. The one intraoperative durotomy occurred while removing a bullet fragment from the L1-2 foramen; the dural tear was covered with dural sealant without direct dural repair, and, after removing the tubular retractor, the paraspinous muscles further sealed the communication between the spine and skin, thus no CSF leak was observed postoperatively. Several potential complications exist related to GSW to the spine. CSF fistulas and infections related to colonic perforation have been previously addressed. The potential for lead toxicity exists; however, this is extremely uncommon. Bullet lodgment in the disc space appears to increase this risk as compared to a projectile within the CSF circulation because synovial fluid is a stronger solvent than CSF. Lead levels can be drawn if this complication is expected [5]. Another potential complication, also rare, is bullet migration. There has been much debate over Magnetic Resonance Imaging (MRI) and its potential to cause ballistic movement within the body. The MRI is rarely needed for the area involved with the GSW; however, these patients sometimes have multiple injuries and may require an MRI of a different body part (e.g., the cervical spine for clearance). Despite initial concerns over the inability to classify the ferromagnetic properties of the many projectile types, studies have since shown that ballistic fragments from GSW can safely be exposed to MRI scans [33,34,37]. Despite this, the topic remains controversial and is usually handled on a patient-by-patient basis at our institution. Finally, GSW to the spine has the potential to cause chronic neuropathic pain. This most frequently occurs with injuries to the conus medullaris and cauda equina regions [35]. Unfortunately, reduction in pain is usually not associated with bullet removal and other methods to treat the chronic pain have variable efficacy [38]. Death is the ultimate complication associated with GSW, although it is rarely related to the injury suffered by the spine GSW. The potential does exist, however, for injuries to the craniocervical junction, as this area controls the respiratory drive. In our series, 10 (6.8%) patients succumb to their injuries during their hospitalization, with 2 (1.3%) of these patients suffering injuries to cord at the C1 level, while the remaining 8 patients died from injuries to other organ systems.
Conclusion The incidence of GSW to the spine in New Orleans is over three times higher than that in the next most violent city. In this urban population, there was a clear correlation between drug use and suffering a GSW to the spine injury. Surgical intervention was seldomly used in these patients and included decompressive procedures in patients with incomplete neurological deficit and compressive pathology, particularly below T11, and instrumented stabilization procedures in patients with unstable fractures. For
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