Curve Behavior of Distal Segments After Posterior-Only Hemivertebra Resection for Congenital Cervicothoracic Scoliosis

Abstract

Study Design: A retrospective and consecutive study.

Objective: To demonstrate the curve evolution of distal non-structural compensatory curves in patients with congenital cervicothoracic hemivertebra (CTH) scoliosis undergoing posterior-only hemivertebra resection and to propose the possible mechanisms of this specific phenomenon.

Summary of Background Data: Though the spinal alignment could be well corrected via posterior hemivertebra resection in CTH patients, the high prevalence of distal curve progression was remarkable. However, the curve behavior of distal non-structural compensatory curves and its possible mechanisms were unclear.

Methods: This study retrospectively reviewed a consecutive series of CTH patients undergoing posterior-only hemivertebra resection with a minimum 24 months follow-up. The parameters measured in coronal plane included local scoliosis, clavicle angle, head shift, and the Cobb angle of distal unfused segments. The distal curve was considered as an emerging scoliosis (ES) if with more than 20° progression and the apex of distal curve no less than 2 levels away from the lower instrumented vertebra.

Results: A total of 51 CTH patients with a mean age of 8.5 ± 3.8 years at surgery and a mean 38.0 ± 5.3 months follow-up were recruited. The correction of local scoliosis and clavicle angle was statistically significant (p < 0.05 for all). The distal compensatory curve was 11.8 ± 5.3° before surgery and 6.5° ± 4.1° after surgery (p < 0.001), which was slightly increased to 11.6° ± 10.9° (p = 0.002) at the latest follow-up. During follow-up, the increase of distal compensatory curve was significantly correlated with the change in clavicle angle (r = 0.49, p = 0.038). The ES was observed in 10 patients (19.6%) with an average value of 28.0 ± 2.1° at diagnosis, including 7 patients within 6 months and 3 patients after 5 years postoperatively. The mean value of ES was 31.9° ± 3.1° at the latest follow-up, while no patients required revision surgery. The ES was classified into compensatory and idiopathic types according to the typical curve behaviors. The compensatory ES usually presented within 6 months after operation and was responsible for further reconstruction of head and shoulder balance. While the idiopathic ES occurred at adolescent which may be related to the rapid body growth.

Conclusions: Distal compensatory curve had a tendency toward slight progression during follow-up in CTH patients with posterior hemivertebra resection surgery. The prevalence of emerging scoliosis was 19.6% and the typical compensatory and idiopathic curve behavior were firstly proposed. Close and longitudinal follow-up was thus highly recommended for CTH patients with posterior HV resection surgery.

Keywords

cervicothoracic hemivertebra / compensatory type / distal curve progression / emerging scoliosis / hemivertebra resection / idiopathic type

References

[1] M. J. McMaster and K. Ohtsuka, “The Natural History of Congenital Scoliosis. A Study of Two Hundred and Fifty-One Patients,” Journal of Bone and Joint Surgery (American Volume) 64 (1982): 1128–1147.

[2] B. Yaszay, M. O’Brien, H. L. Shufflebarger, et al., “Efficacy of Hemivertebra Resection for Congenital Scoliosis: A Multicenter Retrospective Comparison of Three Surgical Techniques,” Spine (Phila pa 1976) 36 (2011): 2052–2060.

[3] S. Li, Z. H. Chen, Y. Qiu, et al., “Coronal Decompensation After Posterior-Only Thoracolumbar Hemivertebra Resection and Short Fusion in Young Children With Congenital Scoliosis,” Spine 1 (2017): 654–660.

[4] Q. Zhuang, J. Zhang, S. Li, S. Wang, J. Guo, and G. Qiu, “One-Stage Posterior-Only Lumbosacral Hemivertebra Resection With Short Segmental Fusion: A More Than 2-Year Follow-Up,” European Spine Journal 25 (2016): 1567–1574.

[5] J. Guo, J. Zhang, S. Wang, et al., “Surgical Outcomes and Complications of Posterior Hemivertebra Resection in Children Younger than 5 Years Old,” Journal of Orthopaedic Surgery and Research 11 (2016): 48.

[6] M. D. Smith, “Congenital Scoliosis of the Cervical or Cervicothoracic Spine,” Orthopedic Clinics of North America 25 (1994): 301–310.

[7] Z. Chen, Y. Qiu, Z. Zhu, et al., “Posterior-Only Hemivertebra Resection for Congenital Cervicothoracic Scoliosis: Correcting Neck Tilt and Balancing the Shoulders,” Spine 43 (2017): 1.

[8] S. Cao, X. Chen, S. Pan, et al., “Evaluation and Comparation of a Novel Surgical Technique and Hemivertebra Resection to the Correction of Congenital Cervical Scoliosis in Lower Cervical and Cervicothoracic Spine,” Neurospine 19, no. 4 (2022): 1071–1083.

[9] H. Q. Zhang, Y. X. Du, J. Y. Liu, et al., “Strategy and Efficacy of Surgery for Congenital Cervicothoracic Scoliosis With or Without Hemivertebra Osteotomy,” Orthopaedic Surgery 14, no. 9 (2022): 2050–2058.

[10] X. Chen, L. Xu, Y. Qiu, et al., “Incidence, Risk Factors, and Evolution of Proximal Junctional Kyphosis After Posterior Hemivertebra Resection and Short Fusion in Young Children With Congenital Scoliosis,” Spine (Phila Pa 1976) 43 (2018): 1193–1200.

[11] X. Yang, Y. Song, L. Liu, et al., “Emerging S-Shaped Curves in Congenital Scoliosis After Hemivertebra Resection and Short Segmental Fusion,” Spine Journal 16 (2016): 1214–1220.

[12] Y. Huang, G. Feng, L. Liu, et al., “Posterior Hemivertebral Resection for Upper Thoracic Congenital Scoliosis: Be Aware of High Risk of Complications,” Journal of Pediatric Orthopaedics. Part B 28 (2019): 1–9.

[13] Z. Liu, B. Jiang, Y. Jiang, et al., “Progressive Coronal Caudal Curve After Corrective Osteotomies for Congenital Cervicothoracic Scoliosis: Incidence and Predictors,” European Spine Journal 33, no. 4 (2024): 1675–1682.

[14] K. Sun, X. Sun, Z. Zhu, et al., “A Novel Classification of Congenital Cervicothoracic Scoliosis: Identification of Coronal Subtypes and Their Prognostic Significance,” European Spine Journal 33, no. 12 (2024): 4426–4436.

[15] B. W. Burkhardt, C. Meyer, G. Wagenpfeil, T. R. Pitzen, and M. Ruf, “The Effect of Cervicodorsal Hemivertebra Resection on Head Tilt and Trunk Shift in Children With Congenital Scoliosis,” Journal of Pediatric Orthopedics 40 (2020): e256.

[16] S. Wang, G. Lin, Y. Yang, et al., “Outcomes of 360° Osteotomy in the Cervicothoracic Spine (C7-T1) for Congenital Cervicothoracic Kyphoscoliosis in Children,” Journal of Bone and Joint Surgery. American Volume 101 (2019): 1357–1365.

[17] Y. Zhang, J. Yang, L. Zhou, A. Pan, and Y. Hai, “Selective Hemivertebrae Resection in a Congenital Scoliosis Patient With Multiple Hemivertebrae Deformities,” European Spine Journal 26 (2017): 1577–1583.

[18] M. Ruf and J. Harms, “Hemivertebra Resection by a Posterior Approach: Innovative Operative Technique and First Results,” Spine (Phila Pa 1976) 27 (2002): 1116–1123.

[19] M. Ruf and J. Harms, “Pedicle Screws in 1-and 2-Year-Old Children: Technique, Complications, and Effect on Further Growth,” Spine (Phila Pa 1976) 27 (2002): E460–E466.

[20] X. S. Qiu, W. W. Ma, W. G. Li, et al., “Discrepancy Between Radiographic Shoulder Balance and Cosmetic Shoulder Balance in Adolescent Idiopathic Scoliosis Patients With Double Thoracic Curve,” European Spine Journal 18 (2009): 45–51.

[21] Y. Atici, Y. E. Akman, M. B. Balioglu, and S. Erdogan, “A Comparison of the Effects of Two Different Techniques on Shoulder Balance in the Treatment of Congenital Scoliosis: Vertical Expandable Prosthetic Titanium Rib and Dual Growing Rod,” Journal of Craniovertebral Junction and Spine 6 (2015): 190–194.

[22] Y. Wang, N. Kawakami, T. Tsuji, et al., “Proximal Junctional Kyphosis Following Posterior Hemivertebra Resection and Short Fusion in Children Younger Than 10 Years,” Clinical Spine Surgery 30 (2017): E370–E376.

[23] J. Zhang, W. Shengru, G. Qiu, B. Yu, W. Yipeng, and K. D. K. Luk, “The Efficacy and Complications of Posterior Hemivertebra Resection,” European Spine Journal 20 (2011): 1692–1702.

[24] Z. Shi, Q. Li, B. Cai, et al., “Causes of the Failure and the Revision Methods for Congenital Scoliosis due to Hemivertebra,” Congenit Anom (Kyoto) 55 (2015): 150–154.

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2024 The Author(s). Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.