O 041 - Long-term outcome after hamstring lengthening in children with CP depends on preoperative hamstring length and velocity

Abstract

Retrospective case series with comparative analysis.To analyze a consecutive cohort of very young patients operated for congenital scoliosis secondary to a single hemivertebra (HV) and compare thoracolumbar (TL) versus lumbosacral (LS) curve results.Despite the published successful results regarding early hemivertebra resection and short fusion for congenital hemivertebrae, literature lacks midterm results, especially in very young children.Patients under 5 years of age, operated by HV resection and transpedicular short fusion, with follow-up longer than 5 years, were included. Preoperative, postoperative (1-year), final radiographic parameters, and complications were recorded. Midterm results were analyzed and TL versus LS curves were compared.Twenty-three patients were included (14 TL and 9 LS HV). The mean age was 3.5 ± 1.7 years and the mean follow-up was 7.6 years (4.7–13.7). The mean preoperative Cobb angle (40.3° ± 6.7°), corrected 65% postoperatively and 50% at final follow-up. The compensatory cranial curve improved spontaneously from 25.3° ± 14.8° to 13.5° ± 12° and finally to 19.9° ± 10.7°. Preoperative coronal balance corrected postoperatively but worsened at the final follow-up. TL curves corrected more initially than LS curves (TL: −29°, 68%, vs. LS: −22°, 59%; p = .043); however, both groups lost correction at the final follow-up (TL: 4°, 56%, vs. LS: 7°, 39%; p = .186). The LS group had a larger preoperative compensatory curve, which corrected with surgery but lost more correction at the final follow-up (p = .046). Segmental kyphosis was especially corrected in the TL group (TL: −14° vs. LS: −2°, p = .018) and was maintained over time.Early hemivertebra resection and transpedicular short fusion allowed good coronal correction initially, which was difficult to maintain at midterm, especially at the LS junction. Sagittal plane correction was excellent in TL deformities and was maintained over time. Results were more challenging in the LS group compared with TL deformities. Guidance to avoid unwanted results is proposed.Level III.