RESUMEN
BACKGROUND: Patients with adolescent idiopathic scoliosis (AIS) often report chronic back pain; however, there is inadequate research on psychological factors associated with pain in this patient population. Pain catastrophizing, a psychological factor that describes a pattern of negative thoughts and feelings about pain, has been associated with poorer responses to medical treatment for pain. The purpose of this study was to report the prevalence of pain catastrophizing in the AIS population and assess its relationship with preoperative and postoperative self-reported outcomes. METHODS: In this prospective cohort study of consecutive patients undergoing posterior spinal fusion (PSF) for AIS, patients experiencing clinically relevant pain catastrophizing, defined as a Pain Catastrophizing Scale for Children (PCS) score in the 75th percentile or higher, were compared with patients with normal PCS scores. Preoperative and 2-year postoperative Scoliosis Research Society Society Questionnaire-30 (SRS-30) scores were correlated with the preoperative PCS score. RESULTS: One hundred and eighty-nine patients underwent PSF for AIS, and 20 (10.6%) were considered to be experiencing pain catastrophizing. Despite comparable demographic and radiographic variables, pain catastrophizing was associated with significantly lower preoperative scores than were found in the normal-PCS group in all SRS-30 domains, including pain (2.98 versus 3.95; p < 0.001), appearance (2.98 versus 3.48; p < 0.001), activity (3.51 versus 4.06; p < 0.001), mental health (3.12 versus 4.01; p < 0.001), and total score (3.18 versus 3.84; p < 0.001), except satisfaction (3.72 versus 3.69; p > 0.999). At 2 years, the pain catastrophizing group experienced significant improvement from their preoperative scores in most SRS-30 domains, including a large clinically relevant improvement in pain (from 2.98 preoperatively to 3.84 postoperatively; p < 0.001) and the total score (from 3.18 to 3.85; p < 0.001), but continued to have lower scores than the normal-PCS group for pain (3.84 versus 4.22; p = 0.028) and the total score (3.85 versus 4.15; p = 0.038). Receiver operating characteristic (ROC) curve analysis indicated that an SRS-30 pain score of <3.5 has good sensitivity for predicting pain catastrophizing (PCS ≥75th percentile). CONCLUSIONS: In this cohort, patients with AIS who exhibited pain catastrophizing experienced significant improvement in self-reported health 2 years after PSF. However, they did not have the same levels of self-reported health as the normal-PCS group. Pain catastrophizing may be identifiable by lower preoperative SRS-30 pain scores. LEVEL OF EVIDENCE: Prognostic Level II . See Instructions for Authors for a complete description of levels of evidence.