Influence of Derotation Connectors on 3D Surgical Correction of Adolescent Idiopathic Scoliosis. Issue 3 (April 2018)

• Record Type: Journal Article
• Authors: Allia, Jérémy; Clément, Jean-Luc; Rampal, Virginie; Leloutre, Béatrice; Rosello, Olivier; Solla, Federico
• Is Part Of: Clinical spine surgery. Volume 31:Issue 3(2018)
• Publication Date: 2018-04
• Subjects: adolescent idiopathic scoliosis -- surgery -- derotation -- translation -- 3D -- CT-scan -- connector -- axial torsion -- rib hump; Spinal cord -- Diseases -- Periodicals; Spinal cord -- Surgery -- Periodicals; 617.56059
• DOI: 10.1097/BSD.0000000000000621
• Languages: English
• ISSNs: 2380-0186

Abstract

Abstract : Study Design: Monocentric study comparing results of simultaneous translation on 2 rods (ST2R) with derotation connectors (prospective series) or without derotation connectors (retrospective series) in Adolescent Idiopathic Scoliosis (AIS) surgery. Objective: The objective of this study was to assess if derotation connectors influence axial, coronal, and sagittal results in AIS surgery. Summary of Background Data: Conventional reduction techniques remain limited in their ability to reduce axial torsion. Direct vertebral derotation technique accomplishes partial axial derotation but decreases thoracic kyphosis. Methods: Monocentric study including AIS surgeries performed using ST2R technique with derotation connectors (group D+, n=44) or without derotation connectors (group D−, n=24). The axial intervertebral rotation was measured between apical and neutral vertebra on pre and postoperative computed tomography scan. T test was used to compare mean values. ANCOVA analyzed the influence of connectors and covariates on the primary outcome, which was the difference between preoperative and postoperative intervertebral rotation. Results: The mean axial torsion gain in the D+ group was 23% (+3.84 degrees, 95% confidence interval, +1.95/+5.73). In the D− group, mean axial torsion increase of 4% (−0.42 degrees, 95% confidence interval, −1.19/+2.03). The result was significantly different between the 2 groups ( P =0.005). The coronal correction of the main curve angle was 80% in the D+ group and 64% in the D− group ( P =0.004). Kyphosis correction was similar between the 2 groups ( P =0.3) with significant increase of thoracic kyphosis in the whole series ( P =0.02) and no patients with postoperative hypokyphosis <10 degrees. Multivariate analysis confirmed the influence of derotation connectors on both axial and coronal correction ( P <0.05). Conclusions: The use of derotation connectors in the surgical treatment of AIS significantly improved axial and coronal correction compared to nonuse of connectors without compromising the sagittal plane. Abstract : Supplemental Digital Content is available in the text.