54. Perioperative outcomes of anterior vertebral spinal tethering vs posterior spinal fusion for skeletally immature patients with idiopathic scoliosis

Abstract

BACKGROUND CONTEXT Correcting scoliosis without fusion can be achieved with anterior vertebral body tethering (AVBT). However, little is known about the perioperative morbidity of AVBT compared with traditional posterior spinal fusion and instrumentation (PSF). PURPOSE The purpose of this study is to compare the perioperative morbidity of AVBT vs PSF in skeletally immature patients with idiopathic scoliosis. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE Skeletally immature patients with idiopathic scoliosis curve magnitude of at least 40° with at least 2-year follow-up were included. Patients with neuromuscular scoliosis were excluded. OUTCOME MEASURES The primary outcome is 30-day readmission. Secondary outcomes include procedure duration, estimated blood loss (EBL), length of stay (LOS), total postoperative opioid morphine equivalent (OME), foley duration, days to solid food, direct cost and revision surgery. METHODS In this IRB-approved retrospective cohort study, operatively managed skeletally immature patients with scoliosis curve magnitude of at least 40° were enrolled and compared with respect to primary and secondary outcomes. RESULTS Of 140 enrolled patients, 42 (30%) underwent AVBT and 98 (70%) underwent PSF. AVBT and PSF patients had no difference in 30-day readmission (5% vs 3%, p=0.63). AVBT patients had shorter procedure time (296±88 minutes vs 428±75 minutes, p<0.01), less EBL (117.7±116 ml vs 210.4±180 ml, p<0.01), shorter LOS (3.6±0.91 days vs 4.7±2.0 days, p<0.01), less total inpatient OME use (p<0.05), shorter foley duration (58±19 hours vs 65±19 hours, p=0.04), less days to solid food (0.9±0.4 vs 1.2±1.1, p=0.03) and decreased overall direct cost in USD ($42,157.10±$14,459 vs $50,277.00±$13,905, p<0.01) compared to PSF patients. The overall revision rate at least two years postoperatively was higher in patients undergoing AVBT than PSF (36% vs 11%, p<0.01). CONCLUSIONS Patients who underwent AVBT had equivalent 30-day readmission rate as well as decreased surgery time, EBL, LOS, inpatient OME use, foley duration, days to solid food and overall direct cost compared to PSF patients. At 2-years postoperative, AVBT patients had 3 times the rate of revision compared to those who underwent PSF. These data can be used in the informed consent process for the surgical management of skeletally immature patients with idiopathic scoliosis. FDA DEVICE/DRUG STATUS Zimmer Spinal Tether (Not approved for this indication) Correcting scoliosis without fusion can be achieved with anterior vertebral body tethering (AVBT). However, little is known about the perioperative morbidity of AVBT compared with traditional posterior spinal fusion and instrumentation (PSF). The purpose of this study is to compare the perioperative morbidity of AVBT vs PSF in skeletally immature patients with idiopathic scoliosis. Retrospective cohort study. Skeletally immature patients with idiopathic scoliosis curve magnitude of at least 40° with at least 2-year follow-up were included. Patients with neuromuscular scoliosis were excluded. The primary outcome is 30-day readmission. Secondary outcomes include procedure duration, estimated blood loss (EBL), length of stay (LOS), total postoperative opioid morphine equivalent (OME), foley duration, days to solid food, direct cost and revision surgery. In this IRB-approved retrospective cohort study, operatively managed skeletally immature patients with scoliosis curve magnitude of at least 40° were enrolled and compared with respect to primary and secondary outcomes. Of 140 enrolled patients, 42 (30%) underwent AVBT and 98 (70%) underwent PSF. AVBT and PSF patients had no difference in 30-day readmission (5% vs 3%, p=0.63). AVBT patients had shorter procedure time (296±88 minutes vs 428±75 minutes, p<0.01), less EBL (117.7±116 ml vs 210.4±180 ml, p<0.01), shorter LOS (3.6±0.91 days vs 4.7±2.0 days, p<0.01), less total inpatient OME use (p<0.05), shorter foley duration (58±19 hours vs 65±19 hours, p=0.04), less days to solid food (0.9±0.4 vs 1.2±1.1, p=0.03) and decreased overall direct cost in USD ($42,157.10±$14,459 vs $50,277.00±$13,905, p<0.01) compared to PSF patients. The overall revision rate at least two years postoperatively was higher in patients undergoing AVBT than PSF (36% vs 11%, p<0.01). Patients who underwent AVBT had equivalent 30-day readmission rate as well as decreased surgery time, EBL, LOS, inpatient OME use, foley duration, days to solid food and overall direct cost compared to PSF patients. At 2-years postoperative, AVBT patients had 3 times the rate of revision compared to those who underwent PSF. These data can be used in the informed consent process for the surgical management of skeletally immature patients with idiopathic scoliosis.