There is little information about national in-hospital complication rates, adverse outcomes, and mortality after spinal fusion for spinal cord injury (SCI). The National Inpatient Sample (NIS) was utilized to identify 31,381 admissions of acute spinal cord injured patients who underwent spinal decompression with laminectomy and/or fusion (lam/fusion) in the United States from 1993 to 2002. Multivariate analysis was performed to analyze the effects of patient and hospital characteristics on outcomes such as mortality, complications, and discharge disposition, which were then stratified by age, level, and type of injury. The overall mortality was 3.0%, with a complication rate of 26.3% and mean length of stay (LOS) of 17 days. Pulmonary complications (14.4%) and postoperative hemorrhages or hematomas (3.8%) were the most common complications reported. One postoperative complication doubled the length of stay, increased the mortality rate by fivefold and added over $50,000 to hospital charges. Age and comorbidities were the main significant predictors of mortality on multivariate analysis. Patients aged >85 or 65-84 had a 44- and 14-fold greater risk of dying compared with patients in the 18-44 age group respectively. Patients with >3 comorbidities also had an increased risk of mortality (odds ratio [OR] = 1.8). Alcohol abuse was the most common medical comorbidity (present in 12% of patients treated). This study represents the first major national estimate of in-hospital mortality and complication rates after nonoperative and operative treatment for SCI.