Treatment of Adolescent Idiopathic Scoliosis with Pedicle Screw-Only Constructs: Minimum 3-Year Follow-Up of 103 Consecutive Cases

Information provided by

Ronald A. Lehman, Jr.

Washington University Medical School

Lawrence G. Lenke, MD

The Jerome J. Gilden Professor of Orthopedic Surgery

Co-Chief Pediatric & Adult Spinal, Scoliosis & Reconstructive Surgery

Kathryn Keeler, MD

Washington University School of Medicine

Yongjung J. Kim, MD

Abstract from the 2006 SRS Annual Meeting

Purpose: To analyze the intermediate-term follow-up of a large,consecutive series of adolescent idiopathic scoliosis (AIS) patients treated with pedicle screw constructs at one institution by radiographic parameters, pulmonary function testing (PFT), Scoliosis Research Society (SRS) scores and complications. There have been no reports of the intermediate-term findings in North America following posterior spinal fusion with the use of pedicle screw-only constructs in a larege series of AIS patients.

Methods: 103 consecutive AIS patients with a minimum 3-yr-follow-up (mean=4.8; range=3.01-7.30 years) were evaluated. Radiographic measurements (AP,LAT,supine,side-bending films) included preoperative (PreO), postoperative(PO), 2-year (2Yr) and final follow-up (FFU). Chart review evaluated: PFTs, SRS scores, presence of thoracoplasty, Lenke classification and complications.

Results: The average age at time of surgery was 15.1+2.2years. The most frequent curve type was Lenke Type1 (40.24%), followed by Lenke Type3 (26.83%). The average main thoracic (MT) curve measured 59.2 +12.2SD (PreO), and corrected to 16.8 +9.9SD (PO) (p<0 .0001). Thoracic kyphosis (T5-12) decreased from 25.81° to 15.5° at FFU (p="0.004)" Nash-Moe grading for apical vertebral rotation (AVR) in the MT curve 2.04 (PreOp) 1.09 (p<0.0001), while AVR TL/L spine 1.6 1.14 (p<0.0001). Importantly, horizontalization of subjacent lower disc measured (-8.32°) PreO and (-0.94°) PO (p<0.001). Finally, clavicle-angle (a) improved (-2.20°) 1.14° PFTs follow-up averaged 2.44yrs with improvement FVC 7.1% FEV1 8.8% (P<0.0001). SRS scores 83% latest follow-up. One case distal adding-on 2 deep wound infections required additional surgery. No neurologic, pseudarthrosis or implant complications developed.

Conclusions:This is the largest (N=103), consecutive series of North American patients with AIS treated with pedicle screws having a minimum 3-year follow-up. The average curve correction was 68% (MT), 50% (PT), and 66% (TL/L) at FFU. We found excellent coronal/sagittal balance, curve correction and improved AVR at follow-up. There were no construct-related complications/decompensation, pseudarthrosis or neurologic deficits.

Updated on: 12/10/09