Introduction: Spinal cord trauma patients suffer a variety of concomitant injuries which can significantly contribute to the development of various complications. Post injury infectious complications substantially increase poor outcomes in these patients and increase hospital resource utilization. The objective of this study was to identify risk factors for infectious complications after motor vehicle blunt spinal cord injury [SCI] and to evaluate the impact of associated injuries in the development of posttraumatic infection [PTI].

Methods: Persons age 18 years and older suffering blunt trauma injuries were selected from the Nationwide Inpatient Sample (2003-2007) utilizing ICD9-CM diagnosis codes. The study population was categorized according to the level of SCI: cervical, thoracic, lumbar and sacral; cases with combinations were excluded from analysis. Associated injuries were also identified: cerebral, thoracic, small bowel, colon, splenic, kidney, ureteral/bladder, long bone and pelvic fractures. PTI complications included: pneumonia (PNA), urinary tract infections (UTI), sepsis, and surgical site infections (SSI). Data were analyzed with univariate (chi-square) and multivariable logistic regression analyses.

Results: 10,783 patients were identified: 6,186 (57.4%) in the cervical group, 3,173 (29.4%) thoracic, 1,167 (10.8%) lumbar, and 257 (2.4%) sacral. Males predominated by a ratio of 3.5:1 (8,410 vs. 2,373). Whites accounted for 72.5% of study population, Blacks (12.9%), and Hispanics (9.1%). 2,373 (22.0%) cases were complicated by PTI. The greatest rate of infection was found in the cervical group (24.7%), followed by thoracic (21.8%), sacral (11.5%), and lumbar (10.6%). Adjusting for age, gender, race, level of SCI, and associated injuries a logistic regression model was created with PTI as the outcome; females and Hispanics were more likely to develop PTI (see table 1). Compared to patients with trauma of the lumbar spine, patients with injuries in cervical and thoracic areas were significantly more likely to experience PTI. Among associated injuries, the greatest likelihood of developing PTI was found in patients with pelvic fractures, thoracic, and cerebral injuries.

Conclusion: Infection rates after traumatic spinal injuries were significantly associated with gender, race, level of spinal cord injury, and associated injuries. Patients at greatest risk for developing posttraumatic infectious complications after spinal trauma were females and Hispanics. Injuries most associated with the development of infection after blunt spinal cord injury were cervical injury and associated pelvic fractures. Further analysis of high risk patients suffering blunt spinal cord injury may lead to preventive strategies to reduce infectious complications.

Predictors of PTI	OddsRatio95% CI
Females	1.14 (1.01 – 1.28)
Hispanics	1.46 (1.21 – 1.74)
Level of SCI:
Cervical	2.70 (2.17 – 3.36)
Thoracic	1.94 (1.54 – 2.44)
Associated injuries:
Pelvic fractures	1.58 (1.29 – 1.93)
Thoracic	1.45 (1.27 – 1.66)
Cranial	1.38 (1.14 – 1.66)

Table 1 *References: males, whites, patients with injuries in lumbar spine and those without associated injuries. PTI-posttraumatic infection. SCI-spinal cord injury.