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Abdominal injuries associated with lumbar spine fractures in blunt trauma
Injury, Int. J. Care Injured 30 (1999) 471±474
www.elsevier.com/locate/injury
Abdominal injuries associated with lumbar spine fractures in blunt trauma Reuven Rabinovici b,*, Philip Ovadia a, Guenther Mathiak a, Fizan Abdullah b a
Department of Surgery, Jeerson Medical College, Philadelphia, PA 19107, USA Section of Trauma and Surgical Critical Care, Yale University School of Medicine, 333 Cedar Street, LH 118, New Haven, CT 06520, USA
b
Received 16 June 1998; received in revised form 16 February 1999; accepted 8 March 1999
Abstract Background: speci®c analysis of the relationship between abdominal injuries and lumbar spine fractures has not yet been reported. Methods: a retrospective review of 258 blunt trauma patients with lumbar spine fractures treated between 1991 and 1996. Results: 26 patients sustained concomitant lumbar spine fractures and abdominal injuries. The mechanism of injury was motor vehicle collision (73%), pedestrian-struck (11%), fall (8%) and assault (8%) resulting in ISS, RTS and mortality of 272 4, 6.5 2 0.4 and 8%, respectively. Forty-four lumbar spine fractures were identi®ed (1.7/pt) in association with splenic (54%), renal (41%), hepatic (32%) and small bowel (23%) injuries and no retroperitoneal involvement. Multilevel lumbar spine fractures were associated with a higher organ injury/fracture ratio compared with single level fractures ( p < 0.01) including a twofold higher incidence of solid organ (spleen, liver and kidney) injury ( p < 0.01). The level and type of fracture did not aect the incidence of total and individual organ injury. Patients with abdominal injuries were more severely injured mainly due to increased incidence of associated thoracic injuries although no signi®cant dierence in mortality was observed. Conclusion: abdominal injuries occurred only in the minority of blunt trauma patients with lumbar spine fractures. These injuries, which followed a similar distribution pattern as in blunt trauma in general, occurred most commonly due to motor vehicle collisions and in association with multilevel vertebral fractures. No correlation with fracture type or level was identi®ed. # 1999 Elsevier Science Ltd. All rights reserved.
1. Introduction
2. Methods
Approximately 8000 to 10,000 spinal cord injuries occur annually in the United States [1, 2], the majority of which result from blunt trauma [3]. Of these, 15% involve the lumbar spine [4]. The anatomical approximation of the lumbar spine and abdominal viscera would appear to predispose to an increased incidence of abdominal injuries in patients with lumbar spine fractures. Nevertheless, this association has not yet been con®rmed and the character of these injuries has not been reported.
All injured patients admitted to Thomas Jeerson University Hospital, an urban, Level I Trauma and Regional Spinal Cord Injury Centre, between January 1,1991 and December 31, 1996 were reviewed retrospectively to identify those who sustained blunt lumbar spine fractures. Data were collected from the computerized trauma registry (Lancet Technology, Cambridge, MA) and from patient charts. Patients were analyzed for abdominal injuries con®rmed at operation or by diagnostic studies, other associated injuries, resultant neurological de®cit and in-hospital mortality. Statistical analysis was performed using the Chi-square and student's t test with a probability value of less than 0.05 considered statistically signi®cant.
* Corresponding author. Tel.: +1-203-785-2572; fax: +1-203-7853950. E-mail address: [email protected] (R. Rabinovici)
0020-1383/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved. PII: S 0 0 2 0 - 1 3 8 3 ( 9 9 ) 0 0 1 3 4 - 5
472
R. Rabinovici et al. / Injury, Int. J. Care Injured 30 (1999) 471±474
Table 1 Demographics of patients with and without intra-abdominal injury. Percentages are per total number of patients in each group. P values refer to patients with abdominal injury versus patients without abdominal injury. NS, not signi®cant
Male:female Age (years) ISS RTS Neurological de®cit Motor vehicle accidents Pedestrian-struck accidents Fall Assault Deaths
Total (n=258)
Patients with abdominal injury (n=26)
Patients without abdominal injury (n=232)
P value
2.0:1 3821 1520.7 7.5020.07 36 (14%) 76 (29%) 12 (5%) 147 (57%) 23 (9%) 8 (3%)
1.6:1 3523 2724 6.5220.4 6 (23%) 19 (73%) 3 (11%) 2 (8%) 2 (8%) 2 (8%)
2.0:1 4021 1220.6 7.6220.06 30 (13%) 57 (25%) 9 (4%) 145 (62%) 21 (9%) 6 (3%)
NS NS < 0.01 < 0.01 NS < 0.01 NS < 0.01 NS NS
Data are presented as mean2S.E.M. where appropriate. 3. Results Out of 258 injured patients with lumbar spine fractures only 26 (10%) suered abdominal injuries (Table 1). The mean age and gender distribution did not dier between patients with or without associated abdominal injuries. Patients with abdominal organ injury were more severely injured, as evidenced by higher ISS and lower RTS, were more often involved in motor vehicle accidents and were less commonly admitted secondary to falls than patients without abdominal pathology. Thirty-six patients had neurological ®ndings. Of these, 3 had complete conal injury, 3 suered incomplete conal injury and the remaining 30 sustained radicular or cauda equina injury. Only 8 of the 256 reviewed patients (3%) died. Although trends toward higher incidence of neurological de®cit and mortality were observed in the abdominal injury group, statistical signi®cance was not reached. In the 26 patients who suered both lumbar spine fractures and abdominal injuries 44 vertebral fractures were identi®ed (Table 2). The most commonly injured abdominal organs were the spleen (24 injuries), kidney and adrenals (18), liver (14), and small intestine and
mesentery (10). Splenic and small bowel/mesentery injuries tended to be associated with lower (L4, L5) and middle (L3) rather than upper (L1, L2) vertebral fractures (Table 2), whereas renal injury tended to occur predominantly in conjunction with upper and middle lumbar vertebral fractures. There was no dierence in occurrence of liver injury among higher versus lower lumbar spine fractures. Analysis by type of vertebral fracture revealed no dierence among body compression, burst and transverse process fractures with respect to mean age, severity and mechanism of injury, frequency of injured abdominal organs, incidence of neurological de®cit or mortality (Table 3). Patients who sustained multilevel vertebral fractures (Table 4) were more severely injured, had a higher organ injury/fracture ratio and a twofold higher incidence of solid organ (spleen, liver, kidney) injury ( p < 0.01, data not shown) when compared with patients who sustained a single level fracture. No dierences in the incidence of neurological de®cit or mortality were observed. When compared with patients with lumbar spine
Table 2 Incidence of organ injury per fracture level. Percentages are per total number of fractures in each level. No signi®cant statistical dierences were identi®ed among the groups Level of fracture Spleen
Kidney/adrenals Liver
Small intestine
L1 (n=10) L2 (n=9) L3 (n=8) L4 (n=9) L5 (n=8) Total (n=44)
4 (40%) 6 (67%) 4 (50%) 2 (22%) 2 (25%) 18 (41%)
2 (20%) 1 (11%) 2 (25%) 2 (22%) 3 (37%) 10 (23%)
4 (40%) 4 (45%) 5 (63%) 7 (78%) 4 (50%) 24 (54%)
5 (50%) 2 (22%) 1 (12%) 3 (33%) 3 (37%) 14 (32%)
Fig. 1. Other injuries associated with blunt lumbar spine fractures. p < 0.01 versus patients without intra-abdominal injury.
R. Rabinovici et al. / Injury, Int. J. Care Injured 30 (1999) 471±474
473
Table 3 Demographics of patients with lumbar spine fracture and abdominal injury by type of fracture. Percentages are per total number of fractures in each group of fracture type Type of fracture
Age (years) ISS RTS Neurological de®cit Motor vehicle accidents Pedestrian-struck accidents Fall Assault Deaths Organ injury/fracture ratio
body compression (n=17)
burst (n=11)
transverse process (n=16)
4025 2524 6.4820.4 2 (12%) 12 (71%) 1 (6%) 1 (6%) 3 (17%) 1.47
2724 3125 5.9520.7 3 (27%) 9 (82%) 1 (9%) 1 (9%) 1 (9%) 1.63
4427 3124 5.820.5 1 (6%) 10 (63%) 2 (13%) 2 (13%) 2 (13%) 1 (6%) 1.31
fractures without abdominal injury, those who sustained concurrent abdominal injury had a higher incidence of thoracic, pelvic and closed head injuries while the incidence of long bone, extra-lumbar spine and facial fractures was similar (Fig. 1). Information regarding the use of seat belts and position in the car was available in 67 (88%) and 72 (95%) of the 76 patients involved in motor vehicle accident, respectively. Only 45% of patients were wearing seat belts at the time of injury. Sixty seven percent of car accident victims were drivers, 20% front seat passenger and 13% back seat passengers. No signi®cant dierence in the use of seat belts and location in the car were observed between patients with or without abdominal injury. Information regarding the type of seat belt used was unavailable. 4. Discussion These data demonstrate that abdominal injuries occur in only 10% of patients with lumbar spine fractures which is similar to the incidence reported in blunt trauma patients in general [5,6]. The 10% associ-
ation rate observed in the present study is the ®rst reported relationship between lumbar spine fractures and abdominal organ injury in the `blunt trauma' patient as previous studies, which reported an incidence of 4±65%, were less speci®c and correlated abdominal injuries with combined thoracic and lumbar spine fractures [7±12]. The low incidence of abdominal injuries in patients with lumbar fracture is somewhat expected. This is because most lumbar fractures result from ¯exion, axial loading, ¯exion-distraction, and shear forces [13] in contrast to abdominal injuries which are commonly secondary to direct forces. On the other hand, a closer association could be expected based upon the anatomical proximity of the lumbar spine and abdominal viscera as well as the signi®cant force required to fracture lumbar vertebra [7]. As expected, patients who sustained vertebral fractures and concurrent abdominal injury were more severely injured than those without abdominal injury possibly re¯ecting the increased force necessary to produce multiple injuries. Seventy three percent of patients with lumbar spine fractures and abdominal injuries were injured in a motor vehicle collision. This percen-
Table 4 Demographics of patients with lumbar spine fracture and abdominal injury by number of levels of fracture. Percentages are per total number of fractures in each group. P values refer to patients with single level versus multilevel fractures. NS, not signi®cant
Age (years) ISS RTS Neurological de®cit Motor vehicle accidents Pedestrian-struck accidents Fall Assault Deaths Organ injury/fracture ratio
Single level fractures (n=14)
Multi level fractures (n=12)
P value
3225 2124 7.8420.4 3 (22%) 12 (86%) 1 (7%) 1 (7%) 1 (7%) 1.14
3825 3425 5.6320.6 3 (25%) 7 (58%) 2 (17%) 1 (8%) 2 (17%) 1 (8%) 1.66
NS NS < 0.01 NS NS NS NS NS NS < 0.01
474
R. Rabinovici et al. / Injury, Int. J. Care Injured 30 (1999) 471±474
tage is much higher compared with that observed in the total group (29%) or in patients with lumbar spine fracture without abdominal injury (25%). The spleen, kidney, liver and small bowel were the most commonly injured organs. This is similar to injury distribution patterns reported in the literature for `blunt trauma' in general [9,14,15,16] and in association with other spinal injuries [7] although renal involvement in this series is more frequent. Interestingly, no other retroperitoneal organs including the pancreas and duodenum were involved in spite of their proximity to the lumbar vertebral column. Renal injuries tended to be associated with high lumbar spine fractures as might be anticipated from renal anatomy and consistent with the view that such injuries should be suspected in patient with blunt trauma involving the lower chest and upper abdomen [17,18]. The spleen (despite its anatomical proximity to the upper lumbar vertebrae) and small bowel (despite its coiling in the entire abdomen) tended to be injured mainly in association with lower lumbar spine fractures. Liver injuries were evenly distributed between lower and upper lumbar spine fractures. Multilevel vertebral fractures were associated with higher organ injury/fracture ratio as compared to single level fractures. This can be attributed to the increased force required to produce multilevel vertebral fractures. Surprisingly, there were no statistically signi®cant dierences in resultant neurological de®cit or mortality between these two groups, possibly due to the small number of cases involved. In addition, it is important to note that the type of the lumbar spine fracture did not aect the overall severity or incidence of abdominal organ injury. Investigation of the extra-abdominal injuries suered by patients with lumbar spine fractures revealed that those patients with abdominal organ injury were also more likely to have thoracic, pelvic and closed head injuries whereas long bone, facial and extra-lumbar spinal fractures occurred with similar frequency as compared with patients without trauma-induced abdominal pathology. The overall mortality of 3% is comparable to other series reporting mortality in lumbar spinal cord injuries [4,7,10] and is lower compared with higher spinal cord injuries. The fact that most neurological injuries were of the nerve root or cauda equina type which are less disabling compared with higher spinal cord injuries, contributes to the reduced mortality observed in this group of patients. While there was a trend towards higher mortality in patients with concurrent abdominal injuries, statistical signi®cance was not reached. A higher mortality would be expected in the abdominal injury group, as abdominal injuries alone have a signi®cant risk of mortality [15,19].
Since no signi®cant dierence in the percent of injured patients wearing seat belts and location in the car were observed between the abdominal injury and the no abdominal injury groups, it is conceivable that both parameters do not determine the risk of having abdominal injuries in addition to lumbar fractures. Nevertheless, because lap seat belts have been shown to cause both abdominal and spinal injuries [9,19,20] and since no data regarding the type of seat belt used was available, no de®nitive conclusion can be drawn. References [1] Spack J, Istre GR. Acute traumatic spinal cord injury surveillance, United States, 1987. MMWR 1988;37:285. [2] DeVivo MJ, Philip RF, Maetz HM, Stover SL. Prevalence of spinal cord injury. Arch Neurol 1980;37:707. [3] DeVivo MJ, Rutt RD, Black KJ, Go BK, Stover SL. Trends in spinal cord injury demographics and treatment outcomes between and 1986. Arch Phys Med Rehab 1992;73:424. [4] Burney RE, Maio RF, Maynard F, Karunas R. Incidence, characteristics, and outcome of spinal cord injury at trauma centers in North America. Arch Surg 1992;128:596. [5] Nahum AM, Siegel AW. The changing panorama of collision injury. Surg Gynaecol Obstet 1971;133:783. [6] Reynolds BM, Balsam NA, Reynolds FX. Falls from heights. A surgical experience of 200 consecutive cases. Ann Surg 1971;174:304. [7] Sturm JT, Perry Jr. JF. Injuries associated with fractures of the transverse processes of thoracic and lumbar vertebrae. J Trauma 1984;24:597. [8] LeGay DA, Petrie DP, Alexander DI. Flexion-distraction injuries of the lumbar spine and associated abdominal trauma. J Trauma 1990;30:436. [9] Williams JS, Kirkpatrick JR. The nature of seat belt injuries. J Trauma 1971;11:207. [10] Anderson PA, Henley MB, Rivara FP, Maier RV. Flexion distraction and chance injuries to the thoracolumbar spine. J Orthop Trauma 1991;5:153. [11] Green DA, Green NE, Spengler DM, Devito DP. Flexion-distraction injuries to the lumbar spine associated with abdominal injuries. J Spinal Disorders 1991;4:312. [12] Saboe LA, Reid DC, Davis LA, Warren SA, Grace MG. Spine trauma and associated injuries. J Trauma 1991;31:43. [13] Denis F. The three-column spine and its signi®cance in the classi®cation of thoracolumbar injuries. Spine 1984;8:817. [14] Strauch GO. Major abdominal trauma in 1971. Am J Surg 1972;125:413. [15] Perry Jr JF. A ®ve-year survey of 125 acute abdominal injuries. J Trauma 1965;5:53. [16] Cox EF. Blunt abdominal trauma. Ann Surg 1983;4:467. [17] Herschorn S, Kodama RT, Abara EO. Genitourinary trauma. In: McMurtry RY, McLellan BA, editors. Blunt trauma. Baltimore: Williams & Wilkins, 1990. p. 283±95. [18] Feliciano DV, Pachter HL. Hepatic trauma revisited. Curr Problems Surg 1989;26:453. [19] Woelfel GF, Moore EE, Cogbill TH, Van Way III CW. Severe thoracic and abdominal injuries associated with lap-belt seatbelts. J Trauma 1984;24:166. [20] Arajarvi E, Santavirta S, Tolonen J. Abdominal injuries sustained in severe trac accidents by seat belts wearers. J Trauma 1987;27:393.
www.elsevier.com/locate/injury
Abdominal injuries associated with lumbar spine fractures in blunt trauma Reuven Rabinovici b,*, Philip Ovadia a, Guenther Mathiak a, Fizan Abdullah b a
Department of Surgery, Jeerson Medical College, Philadelphia, PA 19107, USA Section of Trauma and Surgical Critical Care, Yale University School of Medicine, 333 Cedar Street, LH 118, New Haven, CT 06520, USA
b
Received 16 June 1998; received in revised form 16 February 1999; accepted 8 March 1999
Abstract Background: speci®c analysis of the relationship between abdominal injuries and lumbar spine fractures has not yet been reported. Methods: a retrospective review of 258 blunt trauma patients with lumbar spine fractures treated between 1991 and 1996. Results: 26 patients sustained concomitant lumbar spine fractures and abdominal injuries. The mechanism of injury was motor vehicle collision (73%), pedestrian-struck (11%), fall (8%) and assault (8%) resulting in ISS, RTS and mortality of 272 4, 6.5 2 0.4 and 8%, respectively. Forty-four lumbar spine fractures were identi®ed (1.7/pt) in association with splenic (54%), renal (41%), hepatic (32%) and small bowel (23%) injuries and no retroperitoneal involvement. Multilevel lumbar spine fractures were associated with a higher organ injury/fracture ratio compared with single level fractures ( p < 0.01) including a twofold higher incidence of solid organ (spleen, liver and kidney) injury ( p < 0.01). The level and type of fracture did not aect the incidence of total and individual organ injury. Patients with abdominal injuries were more severely injured mainly due to increased incidence of associated thoracic injuries although no signi®cant dierence in mortality was observed. Conclusion: abdominal injuries occurred only in the minority of blunt trauma patients with lumbar spine fractures. These injuries, which followed a similar distribution pattern as in blunt trauma in general, occurred most commonly due to motor vehicle collisions and in association with multilevel vertebral fractures. No correlation with fracture type or level was identi®ed. # 1999 Elsevier Science Ltd. All rights reserved.
1. Introduction
2. Methods
Approximately 8000 to 10,000 spinal cord injuries occur annually in the United States [1, 2], the majority of which result from blunt trauma [3]. Of these, 15% involve the lumbar spine [4]. The anatomical approximation of the lumbar spine and abdominal viscera would appear to predispose to an increased incidence of abdominal injuries in patients with lumbar spine fractures. Nevertheless, this association has not yet been con®rmed and the character of these injuries has not been reported.
All injured patients admitted to Thomas Jeerson University Hospital, an urban, Level I Trauma and Regional Spinal Cord Injury Centre, between January 1,1991 and December 31, 1996 were reviewed retrospectively to identify those who sustained blunt lumbar spine fractures. Data were collected from the computerized trauma registry (Lancet Technology, Cambridge, MA) and from patient charts. Patients were analyzed for abdominal injuries con®rmed at operation or by diagnostic studies, other associated injuries, resultant neurological de®cit and in-hospital mortality. Statistical analysis was performed using the Chi-square and student's t test with a probability value of less than 0.05 considered statistically signi®cant.
* Corresponding author. Tel.: +1-203-785-2572; fax: +1-203-7853950. E-mail address: [email protected] (R. Rabinovici)
0020-1383/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved. PII: S 0 0 2 0 - 1 3 8 3 ( 9 9 ) 0 0 1 3 4 - 5
472
R. Rabinovici et al. / Injury, Int. J. Care Injured 30 (1999) 471±474
Table 1 Demographics of patients with and without intra-abdominal injury. Percentages are per total number of patients in each group. P values refer to patients with abdominal injury versus patients without abdominal injury. NS, not signi®cant
Male:female Age (years) ISS RTS Neurological de®cit Motor vehicle accidents Pedestrian-struck accidents Fall Assault Deaths
Total (n=258)
Patients with abdominal injury (n=26)
Patients without abdominal injury (n=232)
P value
2.0:1 3821 1520.7 7.5020.07 36 (14%) 76 (29%) 12 (5%) 147 (57%) 23 (9%) 8 (3%)
1.6:1 3523 2724 6.5220.4 6 (23%) 19 (73%) 3 (11%) 2 (8%) 2 (8%) 2 (8%)
2.0:1 4021 1220.6 7.6220.06 30 (13%) 57 (25%) 9 (4%) 145 (62%) 21 (9%) 6 (3%)
NS NS < 0.01 < 0.01 NS < 0.01 NS < 0.01 NS NS
Data are presented as mean2S.E.M. where appropriate. 3. Results Out of 258 injured patients with lumbar spine fractures only 26 (10%) suered abdominal injuries (Table 1). The mean age and gender distribution did not dier between patients with or without associated abdominal injuries. Patients with abdominal organ injury were more severely injured, as evidenced by higher ISS and lower RTS, were more often involved in motor vehicle accidents and were less commonly admitted secondary to falls than patients without abdominal pathology. Thirty-six patients had neurological ®ndings. Of these, 3 had complete conal injury, 3 suered incomplete conal injury and the remaining 30 sustained radicular or cauda equina injury. Only 8 of the 256 reviewed patients (3%) died. Although trends toward higher incidence of neurological de®cit and mortality were observed in the abdominal injury group, statistical signi®cance was not reached. In the 26 patients who suered both lumbar spine fractures and abdominal injuries 44 vertebral fractures were identi®ed (Table 2). The most commonly injured abdominal organs were the spleen (24 injuries), kidney and adrenals (18), liver (14), and small intestine and
mesentery (10). Splenic and small bowel/mesentery injuries tended to be associated with lower (L4, L5) and middle (L3) rather than upper (L1, L2) vertebral fractures (Table 2), whereas renal injury tended to occur predominantly in conjunction with upper and middle lumbar vertebral fractures. There was no dierence in occurrence of liver injury among higher versus lower lumbar spine fractures. Analysis by type of vertebral fracture revealed no dierence among body compression, burst and transverse process fractures with respect to mean age, severity and mechanism of injury, frequency of injured abdominal organs, incidence of neurological de®cit or mortality (Table 3). Patients who sustained multilevel vertebral fractures (Table 4) were more severely injured, had a higher organ injury/fracture ratio and a twofold higher incidence of solid organ (spleen, liver, kidney) injury ( p < 0.01, data not shown) when compared with patients who sustained a single level fracture. No dierences in the incidence of neurological de®cit or mortality were observed. When compared with patients with lumbar spine
Table 2 Incidence of organ injury per fracture level. Percentages are per total number of fractures in each level. No signi®cant statistical dierences were identi®ed among the groups Level of fracture Spleen
Kidney/adrenals Liver
Small intestine
L1 (n=10) L2 (n=9) L3 (n=8) L4 (n=9) L5 (n=8) Total (n=44)
4 (40%) 6 (67%) 4 (50%) 2 (22%) 2 (25%) 18 (41%)
2 (20%) 1 (11%) 2 (25%) 2 (22%) 3 (37%) 10 (23%)
4 (40%) 4 (45%) 5 (63%) 7 (78%) 4 (50%) 24 (54%)
5 (50%) 2 (22%) 1 (12%) 3 (33%) 3 (37%) 14 (32%)
Fig. 1. Other injuries associated with blunt lumbar spine fractures. p < 0.01 versus patients without intra-abdominal injury.
R. Rabinovici et al. / Injury, Int. J. Care Injured 30 (1999) 471±474
473
Table 3 Demographics of patients with lumbar spine fracture and abdominal injury by type of fracture. Percentages are per total number of fractures in each group of fracture type Type of fracture
Age (years) ISS RTS Neurological de®cit Motor vehicle accidents Pedestrian-struck accidents Fall Assault Deaths Organ injury/fracture ratio
body compression (n=17)
burst (n=11)
transverse process (n=16)
4025 2524 6.4820.4 2 (12%) 12 (71%) 1 (6%) 1 (6%) 3 (17%) 1.47
2724 3125 5.9520.7 3 (27%) 9 (82%) 1 (9%) 1 (9%) 1 (9%) 1.63
4427 3124 5.820.5 1 (6%) 10 (63%) 2 (13%) 2 (13%) 2 (13%) 1 (6%) 1.31
fractures without abdominal injury, those who sustained concurrent abdominal injury had a higher incidence of thoracic, pelvic and closed head injuries while the incidence of long bone, extra-lumbar spine and facial fractures was similar (Fig. 1). Information regarding the use of seat belts and position in the car was available in 67 (88%) and 72 (95%) of the 76 patients involved in motor vehicle accident, respectively. Only 45% of patients were wearing seat belts at the time of injury. Sixty seven percent of car accident victims were drivers, 20% front seat passenger and 13% back seat passengers. No signi®cant dierence in the use of seat belts and location in the car were observed between patients with or without abdominal injury. Information regarding the type of seat belt used was unavailable. 4. Discussion These data demonstrate that abdominal injuries occur in only 10% of patients with lumbar spine fractures which is similar to the incidence reported in blunt trauma patients in general [5,6]. The 10% associ-
ation rate observed in the present study is the ®rst reported relationship between lumbar spine fractures and abdominal organ injury in the `blunt trauma' patient as previous studies, which reported an incidence of 4±65%, were less speci®c and correlated abdominal injuries with combined thoracic and lumbar spine fractures [7±12]. The low incidence of abdominal injuries in patients with lumbar fracture is somewhat expected. This is because most lumbar fractures result from ¯exion, axial loading, ¯exion-distraction, and shear forces [13] in contrast to abdominal injuries which are commonly secondary to direct forces. On the other hand, a closer association could be expected based upon the anatomical proximity of the lumbar spine and abdominal viscera as well as the signi®cant force required to fracture lumbar vertebra [7]. As expected, patients who sustained vertebral fractures and concurrent abdominal injury were more severely injured than those without abdominal injury possibly re¯ecting the increased force necessary to produce multiple injuries. Seventy three percent of patients with lumbar spine fractures and abdominal injuries were injured in a motor vehicle collision. This percen-
Table 4 Demographics of patients with lumbar spine fracture and abdominal injury by number of levels of fracture. Percentages are per total number of fractures in each group. P values refer to patients with single level versus multilevel fractures. NS, not signi®cant
Age (years) ISS RTS Neurological de®cit Motor vehicle accidents Pedestrian-struck accidents Fall Assault Deaths Organ injury/fracture ratio
Single level fractures (n=14)
Multi level fractures (n=12)
P value
3225 2124 7.8420.4 3 (22%) 12 (86%) 1 (7%) 1 (7%) 1 (7%) 1.14
3825 3425 5.6320.6 3 (25%) 7 (58%) 2 (17%) 1 (8%) 2 (17%) 1 (8%) 1.66
NS NS < 0.01 NS NS NS NS NS NS < 0.01
474
R. Rabinovici et al. / Injury, Int. J. Care Injured 30 (1999) 471±474
tage is much higher compared with that observed in the total group (29%) or in patients with lumbar spine fracture without abdominal injury (25%). The spleen, kidney, liver and small bowel were the most commonly injured organs. This is similar to injury distribution patterns reported in the literature for `blunt trauma' in general [9,14,15,16] and in association with other spinal injuries [7] although renal involvement in this series is more frequent. Interestingly, no other retroperitoneal organs including the pancreas and duodenum were involved in spite of their proximity to the lumbar vertebral column. Renal injuries tended to be associated with high lumbar spine fractures as might be anticipated from renal anatomy and consistent with the view that such injuries should be suspected in patient with blunt trauma involving the lower chest and upper abdomen [17,18]. The spleen (despite its anatomical proximity to the upper lumbar vertebrae) and small bowel (despite its coiling in the entire abdomen) tended to be injured mainly in association with lower lumbar spine fractures. Liver injuries were evenly distributed between lower and upper lumbar spine fractures. Multilevel vertebral fractures were associated with higher organ injury/fracture ratio as compared to single level fractures. This can be attributed to the increased force required to produce multilevel vertebral fractures. Surprisingly, there were no statistically signi®cant dierences in resultant neurological de®cit or mortality between these two groups, possibly due to the small number of cases involved. In addition, it is important to note that the type of the lumbar spine fracture did not aect the overall severity or incidence of abdominal organ injury. Investigation of the extra-abdominal injuries suered by patients with lumbar spine fractures revealed that those patients with abdominal organ injury were also more likely to have thoracic, pelvic and closed head injuries whereas long bone, facial and extra-lumbar spinal fractures occurred with similar frequency as compared with patients without trauma-induced abdominal pathology. The overall mortality of 3% is comparable to other series reporting mortality in lumbar spinal cord injuries [4,7,10] and is lower compared with higher spinal cord injuries. The fact that most neurological injuries were of the nerve root or cauda equina type which are less disabling compared with higher spinal cord injuries, contributes to the reduced mortality observed in this group of patients. While there was a trend towards higher mortality in patients with concurrent abdominal injuries, statistical signi®cance was not reached. A higher mortality would be expected in the abdominal injury group, as abdominal injuries alone have a signi®cant risk of mortality [15,19].
Since no signi®cant dierence in the percent of injured patients wearing seat belts and location in the car were observed between the abdominal injury and the no abdominal injury groups, it is conceivable that both parameters do not determine the risk of having abdominal injuries in addition to lumbar fractures. Nevertheless, because lap seat belts have been shown to cause both abdominal and spinal injuries [9,19,20] and since no data regarding the type of seat belt used was available, no de®nitive conclusion can be drawn. References [1] Spack J, Istre GR. Acute traumatic spinal cord injury surveillance, United States, 1987. MMWR 1988;37:285. [2] DeVivo MJ, Philip RF, Maetz HM, Stover SL. Prevalence of spinal cord injury. Arch Neurol 1980;37:707. [3] DeVivo MJ, Rutt RD, Black KJ, Go BK, Stover SL. Trends in spinal cord injury demographics and treatment outcomes between and 1986. Arch Phys Med Rehab 1992;73:424. [4] Burney RE, Maio RF, Maynard F, Karunas R. Incidence, characteristics, and outcome of spinal cord injury at trauma centers in North America. Arch Surg 1992;128:596. [5] Nahum AM, Siegel AW. The changing panorama of collision injury. Surg Gynaecol Obstet 1971;133:783. [6] Reynolds BM, Balsam NA, Reynolds FX. Falls from heights. A surgical experience of 200 consecutive cases. Ann Surg 1971;174:304. [7] Sturm JT, Perry Jr. JF. Injuries associated with fractures of the transverse processes of thoracic and lumbar vertebrae. J Trauma 1984;24:597. [8] LeGay DA, Petrie DP, Alexander DI. Flexion-distraction injuries of the lumbar spine and associated abdominal trauma. J Trauma 1990;30:436. [9] Williams JS, Kirkpatrick JR. The nature of seat belt injuries. J Trauma 1971;11:207. [10] Anderson PA, Henley MB, Rivara FP, Maier RV. Flexion distraction and chance injuries to the thoracolumbar spine. J Orthop Trauma 1991;5:153. [11] Green DA, Green NE, Spengler DM, Devito DP. Flexion-distraction injuries to the lumbar spine associated with abdominal injuries. J Spinal Disorders 1991;4:312. [12] Saboe LA, Reid DC, Davis LA, Warren SA, Grace MG. Spine trauma and associated injuries. J Trauma 1991;31:43. [13] Denis F. The three-column spine and its signi®cance in the classi®cation of thoracolumbar injuries. Spine 1984;8:817. [14] Strauch GO. Major abdominal trauma in 1971. Am J Surg 1972;125:413. [15] Perry Jr JF. A ®ve-year survey of 125 acute abdominal injuries. J Trauma 1965;5:53. [16] Cox EF. Blunt abdominal trauma. Ann Surg 1983;4:467. [17] Herschorn S, Kodama RT, Abara EO. Genitourinary trauma. In: McMurtry RY, McLellan BA, editors. Blunt trauma. Baltimore: Williams & Wilkins, 1990. p. 283±95. [18] Feliciano DV, Pachter HL. Hepatic trauma revisited. Curr Problems Surg 1989;26:453. [19] Woelfel GF, Moore EE, Cogbill TH, Van Way III CW. Severe thoracic and abdominal injuries associated with lap-belt seatbelts. J Trauma 1984;24:166. [20] Arajarvi E, Santavirta S, Tolonen J. Abdominal injuries sustained in severe trac accidents by seat belts wearers. J Trauma 1987;27:393.