Surgical treatment of early-onset idiopathic scoliosis in the United States: a trend analysis of 15 years (1997-2012).

Abstract

Early-onset scoliosis is a challenging problem that is defined as a curvature of the spine of more than 10 degrees identified in a child less than 10 years. Early-onset idiopathic scoliosis (EOIS) can cause substantial morbidity and may require surgical intervention. The aim of the present study was to identify the trends of EOIS type of surgeries, length of hospital stay, in-hospital complications, and total inpatient admission charges over a 15-year study period in the United States from 1997 to 2012. This retrospective study used the ICD-9-CM (International Classification of Diseases, Ninth Revision, Clinical Modification) codes from the Healthcare Cost and Utilization Project (HCUP) Kids Inpatient's Database (KID) for a 15-year period (1997-2012). We identified a total of 897 patients with EOIS over the 15-year study period. The present study determines the current trends for EOIS surgeries. The present study had no funding sources or any potential conflicts of interest associated biases. Idiopathic scoliosis patients with ages between 0 and <10 years were identified from the Kids' Inpatient Database with ICD-9-CM code 737.30. Posterior, anterior, and combined spinal surgeries were identified in EOIS through the procedure codes. Patients' gender, discharge diagnosis (comorbidities), hospital length of stay (LOS), mortality rates, hospital charges, and in-hospital complication rate data were collected between 1997 and 2012. The primary grouping variable of the study was the type of surgery (posterior, anterior, and combined). The trends of each variable (female gender, mortality rates, in-hospital complications rates, discharge diagnosis, LOS, and total hospital charges) were assessed for each surgical group separately. Cost inflation of hospital charges was adjusted for the year 2012. An analysis of variance test was used to analyze continuous variables and a chi-square test was used for categorical variables. A linear regression test was used to assess the trend of changes. p≤.05 was considered statistically significant. The study identified 897 patients, with 546 (61%) of them requiring surgery. Spine deformity surgery rates significantly decreased in patients with EOIS over time from 75% in 1997 to 47% in 2012, p=.019. In the surgery cohort, the male to female distribution was 37% and 63%, respectively. The overall mortality rate was 0.1%. The average length of hospital stay was 8 days and the average number of discharge diagnosis was 5.3. Aggregated complications were seen in 6% of the patients. The total mean hospital charge (per 2012 US dollars) was $119,613, which increased significantly for all types of surgeries. Over the 15-year study period, 62% (n=342) of the patients had posterior surgeries, 13% (n=71) of the patients had anterior surgeries, and 24% (n=133) of the patients had combined (anterior and posterior) surgeries. Posterior surgeries increased significantly from 33% in 1997 to 91% in 2012 (p<.004). Combined surgeries saw a significant decline from 50% to 4.3% (0<0.001). Anterior surgeries also decreased from 17% to 4.3% (p<.126), but this did not reach statistical significance. From 1997 to 2012 (15 years) study period of patients with EOIS, posterior-based surgeries significantly increased. The overall surgery rate has significantly decreased for these patients. A significant increase in hospital charges were noticed in posterior, anterior, and combined surgeries.