Advertisement for orthosearch.org.uk
Orthopaedic Proceedings Logo

Receive monthly Table of Contents alerts from Orthopaedic Proceedings

Comprehensive article alerts can be set up and managed through your account settings

View my account settings

Visit Orthopaedic Proceedings at:

Loading...

Loading...

Full Access

FIXED LUMBAR APICAL VERTEBRAL ROTATION PREDICTS SPINAL DECOMPENSATION IN LENKE 3C TYPE ADOLESCENT IDIOPATHIC SCOLIOSIS AFTER POSTERIOR THORACIC CORRECTION AND FUSION

7th Congress of the European Federation of National Associations of Orthopaedics and Traumatology, Lisbon - 4-7 June, 2005



Abstract

Objective: We evaluated retrospectively whether there is a role for selective posterior thoracic correction and fusion in double major curves with third generation instrumentation systems.

Methods: In a retrospective review the radiographs of 36 patients with Lenke 3C type curve patterns and having had a selective posterior thoracic correction and fusion with either the Cotrel-Dubousset instrumentation or the Universal Spine System, were evaluated in terms of coronal and sagittal plane balance, curve flexibility, and curve correction with a minimum follow up of two years. Postoperative coronal spinal decompensation was investigated with respect to preoperative radiographic parameters on standing AP, thoracic and lumbar supine side-bending as well as lateral standing radiographs. Coronal spinal decompensation was defined as plumbline deviation of C7 of more than 2 cm with respect to the center sacral vertical line within two years postoperatively. Two groups of patients were analyzed.

Results: 26 patients (72%) showed satisfactory frontal plane alignment by means of C7 plumb line deviation (group A, 1.2 cm to the left), whereas 10 patients (28%) showed coronal spinal decompensation (group B: 2.7 cm to the left; p=0.003). Group differences, could be revealed for lumbar apical vertebral rotation (Perdriolle) (p=0.02, A: 16°, B: 22°) and the percentage correction (derotation) of lumbar apical vertebrae in lumbar supine side-bending films in comparison to AP standing radiographs (p=0.002, A: 49%, B: 27%). Average thoracic curve correction was 51% in group A and 41% in group B (p=0.05). Average lumbar curve correction was 34% in group A and 23% in group B (p=0.09).

High correlation was revealed between postoperative decompensation and derotation of lumbar apical vertebrae (P=0.62, p< 0.001) with a critical value of 40%. A 2x2 table showed that in patients with lumbar apical vertebral derotation of less than 40% specificity was 90% with regard to postoperative decompensation.

Conclusion: Lumbar apical vertebral derotation of less than 40%, determined on lumbar supine side-bending films in comparison to AP standing radiographs, provided the radiographic prediction of postoperative coronal spinal imbalance. We advice close scrunity of the transverse plane in the lumbar supine side-bending film when planning surgical strategy.

Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.