Comparison of anterior and posterior instrumentation for correction of adolescent thoracic idiopathic scoliosis

• Published in: Spine (Philadelphia, PA. 1976) PA. 1976), 1999-02, Vol.24 (3), p.225-239
• Main Authors: BETZ, R. R, HARMS, J, CLEMENTS, D. H, LENKE, L. G, LOWE, T. G, SHUFFLEBARGER, H. L, JESZENSZKY, D, BEELE, B
• Format: Article
• Language: English
• Subjects: Adolescent; Biological and medical sciences; Blood Loss, Surgical; Bone Nails; Child; Humans; Kyphosis - diagnostic imaging; Kyphosis - surgery; Lordosis - diagnostic imaging; Lordosis - surgery; Lumbar Vertebrae - surgery; Medical sciences; Orthopedic surgery; Postoperative Complications; Prospective Studies; Radiography; Reoperation; Scoliosis - diagnostic imaging; Scoliosis - surgery; Spinal Fusion - instrumentation; Spinal Fusion - methods; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Thoracic Vertebrae - surgery; Thoracoplasty - methods; Treatment Outcome
• ISSN: 0362-2436; 1528-1159
• DOI: 10.1097/00007632-199902010-00007

This was a prospective study of two cohort groups of patients (one group receiving anterior instrumentation and the other posterior instrumentation) receiving treatment for thoracic idiopathic scoliosis. To present the 2-year postoperative results of a prospective multicenter study comparing the use of anterior instrumentation with that of posterior multisegmented hook instrumentation for the correction of adolescent thoracic idiopathic scoliosis. Despite reports of satisfactory results, problems have been reported with posterior systems, including worsening of the lumbar curve after surgery and failure to correct hypokyphosis. Theoretically, the advantages of anterior instrumentation include prevention of lumbar curve decompensation by shortening the convexity of the thoracic curve. In addition, by removing the disc, better correction of thoracic hypokyphosis could be obtained. Seventy-eight patients who underwent an anterior spinal fusion using flexible threaded rods and nuts (Harms-MOSS instrumentation, De Puy-Motech-Acromed, Cleveland, OH) were analyzed and compared with 100 patients who underwent posterior spinal fusion with multisegmented hook systems. Parameters of comparison included coronal and sagittal correction, balance, distal lumbar fusion levels, and complication. All patients had idiopathic thoracic curves of King Types II to V. The average age at surgery was 14 years in each group, the average preoperative curve 57 degrees, and the minimum duration of follow-up for all patients 24 months. All data were collected prospectively and analyzed via Epl into statistical analysis (Centers of Disease Control, Atlanta, GA). Average coronal correction of the main thoracic curve was 58% in the anterior group and 59% in the posterior group (P = 0.92). Analysis of sagittal contour showed that the posterior systems failed to correct a preoperative hypokyphosis (sagittal T5 to T12 less than 20 degrees) in 60% of cases, whereas 81% were normal postoperatively in the anterior group. However, hyperkyphosis (sagittal T5 to T12 greater than 40 degrees) occurred after surgery in 40% of the anterior group when the preoperative kyphosis was greater than 20 degrees. Postoperative coronal balance was equal in both groups. An average of 2.5 (range, 0-6) distal fusion levels were saved using the anterior spinal instrumentation according to the criteria used for determining posterior fusion levels in this study. Selective fusion of the thoracic curve (distal fusion le