Pedicle Screw Placement in Pediatric Scoliosis Surgery: Do non-idiopathic patients have higher misplacement rates?

摘要

Introduction: Pedicle screw misplacement in scoliosis surgery is wellrndocumented in adolescent idiopathic scoliosis (IS), but not in the non-idiopathicrnand skeletally immature population.rnObjective: To evaluate the pedicle screw misplacement rate in childrenrnundergoing surgical treatment for all scoliosis etiologies.rnMaterials and Methods: 1042 pedicle screws were prospectively evaluated forrnmisplacement by CT-scan in 54 children(mean:14.0y, range:4-20) undergoingrnPSI(mean Cobb: 63.2o, range:30-112). Misplacement was defined as: >2mm forrnthe medial cortex, >4mm for the lateral/anterior cortices. Scoliosis etiologiesrnincluded:52% idiopathic, 22% congenital(CS), 26% neuromuscularrnscoliosis(NMS).rnResults: 8.4% of screws were misplaced: 4.5% medially, 3.1% laterally, 0.08%rnanteriorly. Misplacement rates between IS(7.1%) and CS(11.5%,p=.066) trendedrntowards significant difference. The misplacement rate for NMS(8.7%) was notrnhigher when compared with IS(p=.413). Univariate analysis demonstrated norndifference in misplacement rates in children < or >10 years of age(p=0.599).rnDifferences in misplacement rates were found in: proximal(12.5%) vs.rnperiapical(5.0%,p=.001) vs. distal screws(5.5%,p=.003); and Tl(40%,p=.008) andrnT2(19%,p=.024) pedicle screws vs. average misplacement at other levels(8.4%).rnMultivarite analysis demonstrated no difference in misplacement rates betweenrnscoliosis etiology groups. T1 and T2 pedicle screws were 7.9 and 2.8 times more atrnrisk of being misplaced than those at all other levels, respectively. No screwsrnrequired removal or caused complications.rnConclusion: Only a consistent relationship between pedicle screw placement at T1rnand T2 and higher misplacement rate was found.rnSignificance: Although there was a trend toward higher pedicle screwrnmisplacement rate in CS after controlling for confounders, the misplacement raternin this heterogeneous population was the same or lower than reported in the AISrnliterature.