Impact of multilevel facetectomy on segmental spinal flexibility in patients with thoracic adolescent idiopathic scoliosis. (March 2021)

• Record Type: Journal Article
• Authors: Kokabu, Terufumi; Abe, Yuichiro; Yamada, Katsuhisa; Iwasaki, Norimasa; Sudo, Hideki
• Is Part Of: Clinical biomechanics. Volume 83(2021)
• Publication Date: 2021-03
• Subjects: Adolescent idiopathic scoliosis -- Multilevel facetectomy -- Spinal flexibility, in vivo measurements -- Spine biomechanics; Biomechanics -- Periodicals; Osteopathic medicine -- Periodicals; Biomechanics -- Periodicals; Osteopathic Medicine -- Periodicals; 612.76
• DOI: 10.1016/j.clinbiomech.2021.105296
• Languages: English
• ISSNs: 0268-0033

Abstract

Abstract: Background: The aim of this study was to intraoperatively assess the effects of multilevel facetectomy on segmental spinal flexibility in patients with thoracic adolescent idiopathic scoliosis. Methods: Twenty patients who underwent posterior thoracic adolescent idiopathic scoliosis curve correction were evaluated. Compressive or distractive loaded force of 50N was applied on the handle of a compressor or distractor connected to the necks of pedicle screws inserted at T7 to T11. Segmental spinal flexibility rates were calculated based on the distance between screw heads under the loaded and unloaded conditions. In addition, the flexibility rates were obtained before and after multilevel facetectomy. Findings: Absolute flexibility rates of all segments significantly increased after multilevel facetectomy under both compressive and distractive forces ( P < 0.01). The absolute change in the flexibility rate was significantly higher at the concave side than at the convex side under both compressive ( P < 0.01) and distractive loaded forces ( P = 0.046). No significant correlation was found between change in the flexibility rates and preoperative Cobb angle or preoperative curve flexibility. Interpretation: From a biomechanical point of view, multilevel facetectomy provides proper spinal flexibility to improve the correction rate of posterior adolescent idiopathic scoliosis surgery. The effects are higher at the concave side than at the convex side. Highlights: Adolescent idiopathic scoliosis is a structural deformity of the spine. Effects of multilevel facetectomy on segmental spinal flexibility were assessed. Flexibility rates of all segments significantly increased after the facetectomy. Change in the flexibility rate was higher at the concave side than the convex side. Multilevel facetectomy improves the correction rate of surgery.