The goal of surgical treatment of adolescent idiopathic scoliosis (AIS) is to prevent disability associated with curve progression.1 Early studies tended to focus on radiographic measures, such as curve correction and sagittal balance, rather than on improvements in quality of life (QOL).2-5 Although studies have reported on QOL in patients treated surgically for scoliosis,6-11 these studies were largely limited by small sample size and inclusion of patients with congenital and neuromuscular scoliosis,9 lack of a generic measure of QOL,6,7 or lack of surgical treatment of patients in the cohort.10
We conducted a study to determine disease-specific and general health-related QOL (HR-QOL) in young adults who underwent surgical correction of their spinal deformity during adolescence and to evaluate associated complications and reoperations.
Materials and Methods
After obtaining institutional review board approval, we queried the surgical database of a large metropolitan tertiary referral center for consecutive patients who had undergone spine deformity correction between the ages of 10 and 17 years (January 1993–December 2003). Hospital and medical records were retrospectively reviewed to confirm the diagnosis of AIS. Patients with congenital, neuromuscular, juvenile, or infantile scoliosis were excluded. Patients with intraspinal pathology (eg, tethered cord, syringomyelia), developmental delay, chromosomal abnormality, or congenital heart disease were also excluded. Patients were contacted by mail or telephone, and the Scoliosis Research Society–22R (SRS-22R)12-15 and the Short Form–12 (SF-12)16 were administered. Standard demographic and surgical data were also collected.
The SRS-22R is a scoliosis-specific HR-QOL questionnaire with 22 items, 5 domains (pain, activity, appearance, mental, satisfaction), and a total score.12-15 Each domain score ranges from 1 to 5 (higher scores indicating better outcomes). The SRS-22R is the outcome instrument most widely used to measure HR-QOL changes in patients with scoliosis, and it is available in several languages.17-26
The SF-12, a 12-item self-administered short-form health status survey developed in the Medical Outcomes Study, measures patient-based health status. Two composite scores can be calculated: physical composite summary (PCS) and mental composite summary (MCS).16 Using norm-based scoring, all domain scales have a mean (SD) of 50 (10) based on the general 1998 US population. Thus, scores under 50 fall below the general population mean.
In addition, patients were surveyed to determine the incidence of spine-related symptoms and complaints, including activity limitations, rib prominence, waistline asymmetry, back pain, limited range of motion (ROM), shortness of breath, wound/scar problems, lung disease/asthma, heart disease, high blood pressure, and arthritis. Data regarding postoperative treatment regimens of physical therapy, narcotic pain medication, spinal/epidural injections, and nonsteroidal anti-inflammatory drug (NSAID) use were collected. Patients were also queried regarding their current working status and smoking status.
Standard demographic and surgical data were collected from hospital and office charts and radiographs. Data collected included history of bracing, age at index surgery, number of levels fused, surgical approach (anterior, posterior, combined), postoperative complications (eg, ileus, wound infection, anemia, pneumonia), and immediate preoperative and final postoperative radiographic measures. Data on need for subsequent revision surgery and indications for revision surgery were also collected.
Preoperative and latest follow-up radiographs were measured to determine curve magnitude, sagittal and coronal balance, and percentage curve correction. Coronal balance was defined as the distance between a plumb line drawn vertically from the spinous process of C7 and the central sacral line on full-length posteroanterior radiographs. Sagittal balance was defined as the distance of a plumb line drawn vertically from the center of the body of C7 and the posterosuperior endplate of S1.27
Regression analysis was performed to identify factors predictive of SRS-22R total scores. Factors included in the analysis were sex, age at surgery, Lenke type, surgery type (anterior, posterior, anteroposterior), number of levels fused, lowest instrumented vertebra, perioperative complications, percentage curve correction, postoperative coronal and sagittal balance, smoking status, and need for revision surgery. Although age and sex were considered variables outside the surgeon’s control, they were included in the model, as previous studies have shown that SRS scores varied by age and sex both in adolescents28 and adults.29 Significance was set at P < .01. All data analysis was performed with IBM SPSS Version 19.0 (Somers, New York).
Results
Of the 384 postoperative patients identified for study inclusion, 134 (35%) completed surveys. Sixteen patients with nonidiopathic scoliosis were excluded, leaving 118 available for analysis. Of the remaining patients, 248 (64%) could not be contacted because of a change in address or phone number. Two patients (1%) were unwilling to complete survey requests. There was no statistically significant difference in demographics between patients with and without follow-up data available. Demographics are summarized in Table 1. There were 109 females (92%). Mean (SD) age at surgery was 14.1 (1.9) years. Only 37 (31%) were braced before surgery. Table 2 summarizes the radiographic data. Mean (SD) major Cobb angle was 49.7° (7.8°). Eighty-five patients (72%) underwent posterior fusion with instrumentation using hooks only; another 16 (14%) had anterior-only surgery, and another 17 (14%) had combined anterior-posterior surgery. A mean of 7.8 levels were fused. Index surgery data and lowest instrumented vertebra distribution are summarized in Table 3. Mean (SD) percentage curve correction was 48.9% (8.4%).