Ponte osteotomies to treat major thoracic adolescent idiopathic scoliosis curves allow more effective corrective maneuvers.

PURPOSE: There is controversy regarding the effect of the Ponte osteotomies in the improvement of coronal correction, its maintenance during follow-up, and the restoration of thoracic kyphosis in adolescent idiopathic scoliosis (AIS).
METHODS: Seventy-three AIS patients with Lenke type 1-4 curves were included. A prospective description of 43 consecutive patients who underwent apical Ponte osteotomies and sublaminar wires with hybrid instrumentation was retrospectively compared to a historical cohort of 30 patients without "Ponte osteotomies". The surgical details and complications were recorded. We evaluated the radiological measurements and SRS-22 Questionnaire scores over a 2-year follow-up.
RESULTS: The Ponte group achieved better postoperative (70 vs 57 %) and final (62 vs 50 %) main curve correction P < 0.001, with no significant loss of correction (4.2° vs 2.5°) P = 0.2 at the final follow-up (48 vs 106 months). We did not find a difference in thoracic (T5-T12) postoperative (22° vs 24°) and final (25° vs 26°) mean kyphosis angle. However, the "Ponte osteotomies" helped to achieve a normal sagittal profile, increasing preoperative hypokyphotic curves (<10°) from 6° to 17° (control: 9°-12°; P = 0.01); and preoperative hyperkyphotic curves (>40°) from 52° to 26° (control: 46°-39°; P = 0.01). The length of surgery was similar (4.3 vs 4.6 h), as were the SRS-22 scores. No major complications were found.
CONCLUSIONS: Ponte osteotomies in major thoracic AIS curves treated by sublaminar wires allowed more effective corrective maneuvers, which improved coronal correction without a significant loss during follow-up. The sagittal profile appears to be determined by other variables; however, "Ponte osteotomies" facilitate the contouring of the desired kyphosis.