Ponte Osteotomies With Pedicle Screw Instrumentation in the Treatment of Adolescent Idiopathic Scoliosis

Abstract

Study design: Review of prospective database.

Objectives: To report the results of Ponte osteotomy with pedicle screw instrumentation for major thoracic adolescent idiopathic (AIS) curves.

Summary of background data: Ponte osteotomy for achieving coronal and sagittal correction of major thoracic curves in AIS with pedicle screw instrumentation is a widespread technique, but results have not been well described.

Methods: Review of 87 consecutive AIS patients with Lenke 1-4 curves who underwent Ponte osteotomies and pedicle screw instrumentation by 2 surgeons at a single institution. Surgical details, blood loss, and complications were recorded. We evaluated coronal and sagittal radiological measurements and Scoliosis Research Society-22 (SRS-22) questionnaire scores over 2-year follow-up.

Results: The mean preoperative thoracic coronal Cobb angle was 57° ± 9.7°, fulcrum flexibility was 47.2%, and lateral Cobb angle was 17.8° ± 4°. The mean estimated blood loss (EBL), expressed as percent estimated blood volume, was 35.8 ± 20.5 mL. There was significant improvement in coronal thoracic Cobb angle, percent correction, and apical vertebral translation over 2-year follow-up (p < .05). In hypokyphotic curves, there was a significant increase in lateral thoracic T5-T12 kyphosis from 8.1° to 18.3° (p < .001). In hyperkyphotic curves, mean lateral thoracic T5-T12 kyphosis improved from 45° to 26° (p < .001). Median SRS-22 domains were higher after treatment (p < .05). Complications included significant hypotension (1), EBL greater than 75% estimated blood volume (2), and wound infection needing drainage (2). There were neuromonitoring signal changes in 7 patients but no significant neurological complications.

Conclusions: In this case series of major thoracic AIS curves treated with segmental pedicle screw instrumentation and Ponte osteotomies, there was an improvement in the coronal and sagittal radiological parameters. A prospective controlled study is needed to determine whether pedicle screw instrumentation and Ponte osteotomies influence outcomes and complications.

Keywords: Coronal; Curve correction; Sagittal; Spinal deformity; Thoracic.