Skip to main content
SpringerLink
Log in

Fulcrum flexibility of the main curve predicts postoperative shoulder imbalance in selective thoracic fusion of adolescent idiopathic scoliosis

  • Original Article
  • Published:
European Spine Journal Aims and scope Submit manuscript

Abstract

Purpose

To identify preoperative predictors for postoperative shoulder imbalance (PSI) after corrective surgery of adolescent idiopathic scoliosis (AIS) and using the fulcrum-bending radiograph to assess flexibility.

Methods

A consecutive surgical cohort of AIS patients undergoing selective thoracic fusion with alternate-level pedicle screw fixation was prospectively studied. Preoperative anteroposterior, lateral and fulcrum-bending radiographs were analysed. Postoperatively, a minimum of 2 years clinical and imaging follow-up was performed of all patients. PSI was defined as a radiographic shoulder height difference of more than 20 mm.

Results

A total of 80 patients were included, and 14 patients (18%) were confirmed with PSI at final follow-up. The flexibility of MT curve was an independent risk factor for PSI (odds ratio (OR) = 3.3 per 10% decrease, 95% confidence interval (CI) 1.6–8.2). Twenty-seven patients had a preoperative MT flexibility of < 55% (OR = 11.5, 95% CI 2.8–46.2). Postoperative T1 tilt was significantly higher in the PSI group (p < 0.001), and a T1 tilt of more than 9° resulted in 7.2 times higher odds of developing PSI (95% CI 2.0–26.0). Fulcrum-bending correction index (FBCI) was significantly higher in the PSI group at final follow-up, and 25 patients had a final postoperative MT FBCI above 120% (OR = 8.5 (95% CI 2.3–31.0).

Conclusions

A low preoperative curve flexibility is a significant predictor for PSI. The surgical strategy should consider proximal fusion in presence of low-flexibility MT curves and consider less aggressive MT curve correction. Achieving a level T1 should be a main priority during intraoperative correction and may require fusion of the PT curve.

Level of evidence

III.

Graphical abstract

These slides can be retrieved under Electronic Supplementary Material.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6

Similar content being viewed by others

References

  1. Fischer CR, Kim Y (2011) Selective fusion for adolescent idiopathic scoliosis: a review of current operative strategy. Eur Spine J 20:1048–1057

    Article  PubMed  PubMed Central  Google Scholar 

  2. Kuklo TR, Lenke LG, Won DS, Graham EJ, Sweet FA, Betz RR, Bridwell KH, Blanke KM (2001) Spontaneous proximal thoracic curve correction after isolated fusion of the main thoracic curve in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 26:1966–1975

    Article  CAS  Google Scholar 

  3. Rose PS, Lenke LG (2007) Classification of operative adolescent idiopathic scoliosis: treatment guidelines. Orthop Clin North Am 38:521–529

    Article  PubMed  Google Scholar 

  4. Luk KD, Don AS, Chong CS, Wong YW, Cheung KM (2008) Selection of fusion levels in adolescent idiopathic scoliosis using fulcrum bending prediction: a prospective study. Spine (Phila Pa 1976) 33:2192–2198

    Article  Google Scholar 

  5. Samartzis D, Leung Y, Shigematsu H, Natarajan D, Stokes O, Mak KC, Yao G, Luk KD, Cheung KM (2015) Selection of fusion levels using the fulcrum bending radiograph for the management of adolescent idiopathic scoliosis patients with alternate level pedicle screw strategy: clinical decision-making and outcomes. PLoS One 10:e0120302

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  6. Kamerlink JR, Quirno M, Auerbach JD, Milby AH, Windsor L, Dean L, Dryer JW, Errico TJ, Lonner BS (2010) Hospital cost analysis of adolescent idiopathic scoliosis correction surgery in 125 consecutive cases. J Bone Jt Surg Am 92:1097–1104

    Article  Google Scholar 

  7. Larson AN, Aubin CE, Polly DW Jr, Ledonio CG, Lonner BS, Shah SA, Richards BS 3rd, Erickson MA, Emans JB, Weinstein SL, Minimize Implants Maximize Outcomes Study G (2013) Are more screws better? A systematic review of anchor density and curve correction in adolescent idiopathic scoliosis. Spine Deform 1:237–247

    Article  PubMed  Google Scholar 

  8. Larson AN, Polly DW Jr, Ackerman SJ, Ledonio CG, Lonner BS, Shah SA, Emans JB, Richards BS 3rd, Minimize Implants Maximize Outcomes Study G (2016) What would be the annual cost savings if fewer screws were used in adolescent idiopathic scoliosis treatment in the US? J Neurosurg Spine 24:116–123

    Article  PubMed  Google Scholar 

  9. Gotfryd AO, Silber Caffaro MF, Meves R, Avanzi O (2017) Predictors for postoperative shoulder balance in lenke 1 adolescent idiopathic scoliosis: a prospective cohort study. Spine Deform 5:66–71

    Article  PubMed  Google Scholar 

  10. Hong JY, Suh SW, Modi HN, Yang JH, Park SY (2013) Analysis of factors that affect shoulder balance after correction surgery in scoliosis: a global analysis of all the curvature types. Eur Spine J 22:1273–1285

    Article  PubMed  PubMed Central  Google Scholar 

  11. Kuklo TR, Lenke LG, Graham EJ, Won DS, Sweet FA, Blanke KM, Bridwell KH (2002) Correlation of radiographic, clinical, and patient assessment of shoulder balance following fusion versus nonfusion of the proximal thoracic curve in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 27:2013–2020

    Article  Google Scholar 

  12. Namikawa T, Matsumura A, Kato M, Hayashi K, Nakamura H (2015) Radiological assessment of shoulder balance following posterior spinal fusion for thoracic adolescent idiopathic scoliosis. Scoliosis 10:S18

    Article  PubMed  PubMed Central  Google Scholar 

  13. Smyrnis PN, Sekouris N, Papadopoulos G (2009) Surgical assessment of the proximal thoracic curve in adolescent idiopathic scoliosis. Eur Spine J 18:522–530

    Article  PubMed  PubMed Central  Google Scholar 

  14. Tang X, Luo X, Liu C, Fu J, Yao Z, Du J, Wang Y, Zhang Y, Zheng G (2016) The spontaneous development of cosmetic shoulder balance and shorter segment fusion in adolescent idiopathic scoliosis with Lenke I curve: a consecutive study followed up for 2 to 5 years. Spine (Phila Pa 1976) 41:1028–1035

    Article  Google Scholar 

  15. Zang L, Fan N, Hai Y, Lu SB, Su QJ, Yang JC, Guan L, Kang N, Meng XL, Liu YZ (2016) Evaluation of the predictors of postoperative aggravation of shoulder imbalance in severe and rigid thoracic or thoracolumbar scoliosis. Eur Spine J 25:3353–3365

    Article  PubMed  Google Scholar 

  16. Lee CK, Denis F, Winter RB, Lonstein JE (1993) Analysis of the upper thoracic curve in surgically treated idiopathic scoliosis. A new concept of the double thoracic curve pattern. Spine (Phila Pa 1976) 18:1599–1608

    Article  CAS  Google Scholar 

  17. Lenke LG, Betz RR, Harms J, Bridwell KH, Clements DH, Lowe TG, Blanke K (2001) Adolescent idiopathic scoliosis: a new classification to determine extent of spinal arthrodesis. J Bone Jt Surg Am 83:1169–1181

    Article  Google Scholar 

  18. Li J, Dumonski ML, Samartzis D, Hong J, He S, Zhu X, Wang C, Vaccaro AR, Albert TJ, Li M (2011) Coronal deformity correction in adolescent idiopathic scoliosis patients using the fulcrum-bending radiograph: a prospective comparative analysis of the proximal thoracic, main thoracic, and thoracolumbar/lumbar curves. Eur Spine J 20:105–111

    Article  PubMed  Google Scholar 

  19. Yao G, Cheung JPY, Shigematsu H, Ohrt-Nissen S, Cheung KMC, Luk KDK, Samartzis D (2017) Characterization and predictive value of segmental curve flexibility in adolescent idiopathic scoliosis patients. Spine (Phila Pa 1976) 42:1622–1628

    Article  Google Scholar 

  20. Elsebaie HB, Dannawi Z, Altaf F, Zaidan A, Al Mukhtar M, Shaw MJ, Gibson A, Noordeen H (2016) Clinically orientated classification incorporating shoulder balance for the surgical treatment of adolescent idiopathic scoliosis. Eur Spine J 25:430–437

    Article  PubMed  CAS  Google Scholar 

  21. Ilharreborde B, Even J, Lefevre Y, Fitoussi F, Presedo A, Souchet P, Pennecot GF, Mazda K (2008) How to determine the upper level of instrumentation in Lenke types 1 and 2 adolescent idiopathic scoliosis: a prospective study of 132 patients. J Pediatr Orthop 28:733–739

    Article  PubMed  Google Scholar 

  22. Matsumoto M, Watanabe K, Kawakami N, Tsuji T, Uno K, Suzuki T, Ito M, Yanagida H, Minami S, Akazawa T (2014) Postoperative shoulder imbalance in Lenke Type 1A adolescent idiopathic scoliosis and related factors. BMC Musculoskelet Disord 15:366

    Article  PubMed  PubMed Central  Google Scholar 

  23. Suk SI, Kim JH, Kim SS, Lim DJ (2012) Pedicle screw instrumentation in adolescent idiopathic scoliosis (AIS). Eur Spine J 21:13–22

    Article  PubMed  Google Scholar 

  24. Cheung KM, Natarajan D, Samartzis D, Wong YW, Cheung WY, Luk KD (2010) Predictability of the fulcrum bending radiograph in scoliosis correction with alternate-level pedicle screw fixation. J Bone Joint Surg Am 92:169–176

    Article  PubMed  Google Scholar 

  25. Cheung KM, Luk KD (1997) Prediction of correction of scoliosis with use of the fulcrum bending radiograph. J Bone Joint Surg Am 79:1144–1150

    Article  PubMed  CAS  Google Scholar 

  26. Li J, Cheung KM, Samartzis D, Ganal-Antonio AK, Zhu X, Li M, Luk KD (2016) Key-vertebral screws strategy for main thoracic curve correction in patients with adolescent idiopathic scoliosis. Clin Spine Surg 29:E434–E441

    Article  PubMed  Google Scholar 

  27. Luk KD, Cheung WY, Wong Y, Cheung KM, Wong YW, Samartzis D (2012) The predictive value of the fulcrum bending radiograph in spontaneous apical vertebral derotation in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 37:E922–E926

    Article  Google Scholar 

  28. Shigematsu H, Cheung JP, Bruzzone M, Matsumori H, Mak KC, Samartzis D, Luk KD (2017) Preventing fusion mass shift avoids postoperative distal curve Adding-on in adolescent idiopathic scoliosis. Clin Orthop Relat Res 475:1448–1460

    Article  PubMed  PubMed Central  Google Scholar 

  29. Nash CL Jr, Moe JH (1969) A study of vertebral rotation. J Bone Joint Surg Am 51:223–229

    Article  PubMed  Google Scholar 

  30. Wang Y, Hansen ES, Hoy K, Wu C, Bunger CE (2011) Distal adding-on phenomenon in Lenke 1A scoliosis: risk factor identification and treatment strategy comparison. Spine (Phila Pa 1976) 36:1113–1122

    Article  Google Scholar 

  31. Qiu XS, Ma WW, Li WG, Wang B, Yu Y, Zhu ZZ, Qian BP, Zhu F, Sun X, Ng BK, Cheng JC, Qiu Y (2009) Discrepancy between radiographic shoulder balance and cosmetic shoulder balance in adolescent idiopathic scoliosis patients with double thoracic curve. Eur Spine J 18:45–51

    Article  PubMed  Google Scholar 

  32. Ohrt-Nissen S, Cheung JPY, Hallager DW, Gehrchen M, Kwan K, Dahl B, Cheung KMC, Samartzis D (2017) Reproducibility of thoracic kyphosis measurements in patients with adolescent idiopathic scoliosis. Scoliosis Spinal Disord 12:4

    Article  PubMed  PubMed Central  Google Scholar 

  33. Akel I, Pekmezci M, Hayran M, Genc Y, Kocak O, Derman O, Erdogan I, Yazici M (2008) Evaluation of shoulder balance in the normal adolescent population and its correlation with radiological parameters. Eur Spine J 17:348–354

    Article  PubMed  Google Scholar 

  34. Hosmer D (2000) Applied logistic regression. Wiley, Inc., New York

    Book  Google Scholar 

  35. Kwan MK, Wong KA, Lee CK, Chan CY (2016) Is neck tilt and shoulder imbalance the same phenomenon? A prospective analysis of 89 adolescent idiopathic scoliosis patients (Lenke type 1 and 2). Eur Spine J 25:401–408

    Article  PubMed  Google Scholar 

  36. Ono T, Bastrom TP, Newton PO (2012) Defining 2 components of shoulder imbalance: clavicle tilt and trapezial prominence. Spine (Phila Pa 1976) 37:E1511–E1516

    Article  Google Scholar 

  37. de Kleuver M, Lewis SJ, Germscheid NM, Kamper SJ, Alanay A, Berven SH, Cheung KM, Ito M, Lenke LG, Polly DW, Qiu Y, van Tulder M, Shaffrey C (2014) Optimal surgical care for adolescent idiopathic scoliosis: an international consensus. Eur Spine J 23:2603–2618

    Article  PubMed  Google Scholar 

  38. Chang DG, Kim JH, Kim SS, Lim DJ, Ha KY, Suk SI (2014) How to improve shoulder balance in the surgical correction of double thoracic adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 39:E1359–E1367

    Article  Google Scholar 

  39. Gomez JA, Matsumoto H, Colacchio ND, Roye DP Jr, Sucato DJ, Richards BS, Emans JB, Erickson MA, Sanders JO, Lenke LG, Vitale MG (2014) Risk factors for coronal decompensation after posterior spinal instrumentation and fusion in adolescent idiopathic scoliosis. Spine Deform 2:380–385

    Article  PubMed  Google Scholar 

  40. Cao K, Watanabe K, Hosogane N, Toyama Y, Yonezawa I, Machida M, Yagi M, Kaneko S, Kawakami N, Tsuji T, Matsumoto M (2014) Association of postoperative shoulder balance with adding-on in Lenke Type II adolescent idiopathic scoliosis. Spine 39:E705–E712

    Article  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, SAR, China

    Soren Ohrt-Nissen, Vijay H. D. Kamath, Dino Samartzis, Keith Dip Kei Luk & Jason Pui Yin Cheung

  2. Department of Orthopaedic Surgery, Spine Unit, Rigshospitalet, Copenhagen, Denmark

    Soren Ohrt-Nissen

Authors
  1. Soren Ohrt-Nissen
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Vijay H. D. Kamath
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Dino Samartzis
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Keith Dip Kei Luk
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Jason Pui Yin Cheung
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Jason Pui Yin Cheung.

Ethics declarations

Conflict of interest

No financial or competing interests in relation to this work.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (PPTX 11160 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Ohrt-Nissen, S., Kamath, V.H.D., Samartzis, D. et al. Fulcrum flexibility of the main curve predicts postoperative shoulder imbalance in selective thoracic fusion of adolescent idiopathic scoliosis. Eur Spine J 27, 2251–2261 (2018). https://doi.org/10.1007/s00586-018-5669-y

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00586-018-5669-y

Keywords

Search

Navigation