[Comparison of clinical features and surgical outcomes in patients with cervicothoracic hemivertebra at different ages].

<b>Objective:</b> To investigate the clinical characteristics of children with cervicothoracic hemivertebra at different ages and evaluate the surgical outcomes of hemivertebra resection. <b>Methods:</b> This retrospective cohort study analyzed clinical and radiographic data of 35 children (under 18 years old) with cervicothoracic hemivertebra who underwent one-stage posterior hemivertebra resection at the Department of Spine Surgery, Second Xiangya Hospital of Central South University, from June 2005 to June 2022. The cohort included 19 males and 16 females, with a surgical age of (9.7±4.1) years (range: 3 to <18 years). Patients were divided into three groups based on initial surgical age: preschool group (≤5 years, <i>n</i>=10), school-age group (6 to 10 years, <i>n</i>=10), and adolescent group (11 to <18 years, <i>n</i>=15). The intraoperative blood loss, operative time, number of fixed vertebrae, and perioperative and postoperative complications were recorded. Radiographic measurements were taken preoperatively, postoperatively, and at final follow-up, including the Cobb angle of the primary curve, curve length, distal curve Cobb angle, neck tilt, shoulder balance, coronal balance, trunk tilt, clavicle angle, head deviation, and local kyphosis. Statistical analyses included one-way ANOVA, Kruskal-Wallis <i>H</i> test, chi-square test, and Fisher's exact test. <b>Results:</b> The operative time was (333±74) minutes (range:200 to 450 minutes), the intraoperative blood loss was (419±132) ml (range:200 to 650 ml), and the number of fixed vertebrae was (6.0±2.7) segments (range:2 to 12 segments). Preoperatively, the preschool group had a smaller primary curve Cobb angle compared to the adolescent group (33.6°±8.4° <i>vs.</i> 43.0°±9.4°, <i>F</i>=3.394, <i>P</i>=0.046) and distal curve Cobb angle (6.4°±2.4° <i>vs.</i>11.9°±4.5°,<i>F</i>=6.550,<i>P</i>=0.038). The preschool group had better coronal balance ((8.8±4.3) mm <i>vs.</i> (20.2±11.7)mm, <i>F</i>=9.448, <i>P</i>=0.009) and trunk tilt (4.0°±2.0°<i>vs.</i>7.0°±3.0°,<i>F</i>=4.343,<i>P</i>=0.029) than the school-age group. The preschool group had fewer fused vertebrae than the school-age and adolescent groups (3.8±1.6 <i>vs.</i> 7.0±2.6 <i>vs.</i> 6.8±2.6, <i>F</i>=10.480, <i>P</i>=0.005). The preschool group also had less intraoperative blood loss than the adolescent groups ((320±125) ml <i>vs.</i> (480±113) ml, <i>F</i>=8.666, <i>P</i>=0.013). However, no significant differences were found in postoperative and final follow-up measurements of primary and distal curve Cobb angles, neck tilt, shoulder balance, coronal balance, trunk tilt, clavicle angle, head deviation, local kyphosis, or complication rates (all <i>P</i>>0.05). <b>Conclusions:</b> Children with cervicothoracic hemivertebra across different age groups exhibit similar surgical outcomes and complication rates. But the preschool group had fewer fixed segments and less intraoperative blood loss, suggesting that this age group is an ideal time for surgery.