Advertisement

A critical thoracic kyphosis is required to prevent sagittal plane deterioration in selective thoracic fusions in Lenke I and II AIS

  • Dominique A. RothenfluhEmail author
  • Alexandra Stratton
  • Colin Nnadi
  • Nicolas Beresford-Cleary
Original Article

Abstract

Purpose

Thoracic hypokyphosis following AIS correction may be associated with reduced lumbar lordosis with potential adverse effects on the global sagittal balance. In the present study, we were interested in how the amount of thoracic kyphosis influences the sagittal profile and balance in selective thoracic (STF) and thoracolumbar fusions.

Methods

Out of 154 patients, 86 patients had correction of AIS Lenke I or II with a side-loading pedicle screw system and completed a 2-year follow-up. Patient factors such as age, Risser grade, lowest and upper instrumented vertebra, and lumbar modifier were recorded. Coronal Cobb and sagittal parameters were measured using Surgimap. Statistical analysis according to distributions and multiple linear and logistic regressions was performed using STATA for Mac v13.

Results

In STF, logistic regression against post-operative change in SVA versus thoracic kyphosis allowed calculation of a critical thoracic kyphosis of 23° (ROC AUC 0.65, spec 0.70, sens 0.63), below which deterioration of the sagittal vertical axis is more likely (PPV 71.4%). Patients with hypokyphosis exhibited an increase in the SVA (pre-operative 7.2 ± 37.1 mm vs. 23.1 ± 27.6 mm at 2 years, p = 0.0164), whereas it was maintained from pre-operative to 2 years post-operative if thoracic kyphosis is above 23° (pre-operative 2.5 ± 28.9 mm vs. 5.4 ± 26.9 mm at 2 years, p = 0.579).

Conclusion

A critical thoracic kyphosis of 23° and more should be aimed for in hypokyphotic patients to potentially avoid post-operative sagittal plane deterioration with mechanical and likely also clinical consequences.

Graphic abstract

These slides can be retrieved under Electronic Supplementary Material.

Keywords

Adolescent idiopathic scoliosis Hypokyphosis Sagittal plane Thoracic kyphosis 

Notes

Compliance with ethical standards

Conflict of interest

The authors declare no conflicts of interest related to this work.

Supplementary material

586_2019_6093_MOESM1_ESM.pptx (188 kb)
Supplementary material 1 (PPTX 188 kb)

References

  1. 1.
    Bridwell KH (1999) Surgical treatment of idiopathic adolescent scoliosis. Spine 24:2607–2616CrossRefGoogle Scholar
  2. 2.
    Majdouline Y, Aubin CE, Robitaille M, Sarwark JF, Labelle H (2007) Scoliosis correction objectives in adolescent idiopathic scoliosis. J Pediatr Orthop 27:775–781.  https://doi.org/10.1097/BPO.0b013e31815588d8 CrossRefGoogle Scholar
  3. 3.
    La Grone MO (1988) Loss of lumbar lordosis. A complication of spinal fusion for scoliosis. Orthop Clin N Am 19:383–393Google Scholar
  4. 4.
    Abelin-Genevois K, Estivalezes E, Briot J, Sévely A, Sales de Gauzy J, Swider P (2015) Spino-pelvic alignment influences disc hydration properties after AIS surgery: a prospective MRI-based study. Eur Spine J 24:1183–1190.  https://doi.org/10.1007/s00586-015-3875-4 CrossRefGoogle Scholar
  5. 5.
    de Jonge T, Dubousset JF, Illés T (2002) Sagittal plane correction in idiopathic scoliosis. Spine 27:754–760CrossRefGoogle Scholar
  6. 6.
    Matsumoto H, Colacchio ND, Schwab FJ, Lafage V, Roye DP, Vitale MG (2015) Flatback revisited: reciprocal loss of lumbar lordosis following selective thoracic fusion in the setting of adolescent idiopathic scoliosis. Spine Deform 3:345–351.  https://doi.org/10.1016/j.jspd.2015.01.004 CrossRefGoogle Scholar
  7. 7.
    Newton PO, Yaszay B, Upasani VV et al (2010) Preservation of thoracic kyphosis is critical to maintain lumbar lordosis in the surgical treatment of adolescent idiopathic scoliosis. Spine 35:1365–1370.  https://doi.org/10.1097/BRS.0b013e3181dccd63 CrossRefGoogle Scholar
  8. 8.
    Takayama K, Nakamura H, Matsuda H (2009) Low back pain in patients treated surgically for scoliosis: longer than sixteen-year follow-up. Spine 34:2198–2204.  https://doi.org/10.1097/BRS.0b013e3181b3f31f CrossRefGoogle Scholar
  9. 9.
    Hayes MA, Tompkins SF, Herndon WA, Gruel CR, Kopta JA, Howard TC (1988) Clinical and radiological evaluation of lumbosacral motion below fusion levels in idiopathic scoliosis. Spine 13:1161–1167CrossRefGoogle Scholar
  10. 10.
    Ilharreborde B, Morel E, Mazda K, Dekutoski MB (2009) Adjacent segment disease after instrumented fusion for idiopathic scoliosis: review of current trends and controversies. J Spinal Disord Tech 22:530–539.  https://doi.org/10.1097/BSD.0b013e31818d64b7 CrossRefGoogle Scholar
  11. 11.
    Bernstein P, Hentschel S, Platzek I et al (2014) Thoracal flat back is a risk factor for lumbar disc degeneration after scoliosis surgery. Spine J 14:925–932.  https://doi.org/10.1016/j.spinee.2013.07.426 CrossRefGoogle Scholar
  12. 12.
    Lowe TG, Lenke L, Betz R et al (2006) Distal junctional kyphosis of adolescent idiopathic thoracic curves following anterior or posterior instrumented fusion: incidence, risk factors, and prevention. Spine 31:299–302.  https://doi.org/10.1097/01.brs.0000197221.23109.fc CrossRefGoogle Scholar
  13. 13.
    Lonner BS, Ren Y, Newton PO et al (2017) Risk factors of proximal junctional kyphosis in adolescent idiopathic scoliosis—the pelvis and other considerations. Spine Deform 5:181–188.  https://doi.org/10.1016/j.jspd.2016.10.003 CrossRefGoogle Scholar
  14. 14.
    Abelin-Genevois K, Sassi D, Verdun S, Roussouly P (2018) Sagittal classification in adolescent idiopathic scoliosis: original description and therapeutic implications. Eur Spine J 48:786.  https://doi.org/10.1007/s00586-018-5613-1 Google Scholar
  15. 15.
    Schwab FJ, Blondel B, Bess S et al (2013) Radiographical spinopelvic parameters and disability in the setting of adult spinal deformity. Spine 38:E803–E812.  https://doi.org/10.1097/BRS.0b013e318292b7b9 CrossRefGoogle Scholar
  16. 16.
    Schwab F, Ungar B, Blondel B et al (2012) Scoliosis research society—schwab adult spinal deformity classification. Spine 37:1077–1082.  https://doi.org/10.1097/BRS.0b013e31823e15e2 CrossRefGoogle Scholar
  17. 17.
    Yilgor C, Sogunmez N, Boissière L et al (2017) Global Alignment and Proportion (GAP) Score: development and validation of a new method of analyzing spinopelvic alignment to predict mechanical complications after adult spinal deformity surgery. J Bone Joint Surg 99:1661–1672.  https://doi.org/10.2106/JBJS.16.01594 CrossRefGoogle Scholar
  18. 18.
    Somerville EW (1952) Rotational lordosis: the development of the single curve. J Bone Joint Surg 34-B:421–427CrossRefGoogle Scholar
  19. 19.
    Ilharreborde B (2018) Sagittal balance and idiopathic scoliosis: does final sagittal alignment influence outcomes, degeneration rate or failure rate. Eur Spine J 27:48–58.  https://doi.org/10.1007/s00586-018-5472-9 CrossRefGoogle Scholar
  20. 20.
    Clément JL, Pelletier Y, Solla F, Rampal V (2018) Surgical increase in thoracic kyphosis increases unfused lumbar lordosis in selective fusion for thoracic adolescent idiopathic scoliosis. Eur Spine J.  https://doi.org/10.1007/s00586-018-5740-8 Google Scholar
  21. 21.
    Senteler M, Weisse B, Snedeker JG, Rothenfluh DA (2014) Pelvic incidence–lumbar lordosis mismatch results in increased segmental joint loads in the unfused and fused lumbar spine. Eur Spine J 23:1384–1393.  https://doi.org/10.1007/s00586-013-3132-7 CrossRefGoogle Scholar
  22. 22.
    Lonner BS, Lazar-Antman MA, Sponseller PD et al (2012) Multivariate analysis of factors associated with kyphosis maintenance in adolescent idiopathic scoliosis. Spine 37:1297–1302.  https://doi.org/10.1097/BRS.0b013e318247e9a6 CrossRefGoogle Scholar
  23. 23.
    Holewijn RM, Schlösser TP, Bisschop A et al (2015) How Does Spinal Release and Ponte Osteotomy Improve Spinal Flexibility? The Law of Diminishing Returns. Spine Deform 3:489–495.  https://doi.org/10.1016/j.jspd.2015.03.006 CrossRefGoogle Scholar
  24. 24.
    Luk KD, Vidyadhara S, Lu DS, Wong YW, Cheung WY, Cheung KM (2010) Coupling between sagittal and frontal plane deformity correction in idiopathic thoracic scoliosis and its relationship with postoperative sagittal alignment. Spine 35:1158–1164.  https://doi.org/10.1097/brs.0b013e3181bb49f3 CrossRefGoogle Scholar
  25. 25.
    Pasha S, Cahill PJ, Dormans JP, Flynn JM (2016) Characterizing the differences between the 2D and 3D measurements of spine in adolescent idiopathic scoliosis. Eur Spine J 25:3137–3145.  https://doi.org/10.1007/s00586-016-4582-5 CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Oxford University Hospitals NHS Foundation TrustNuffield Orthopaedic CentreOxfordUK
  2. 2.Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), Botnar Research CentreUniversity of OxfordOxfordUK
  3. 3.The Ottawa HospitalUniversity of OttawaOttawaCanada

Personalised recommendations