Iliac screw instrumentation to the pelvis in children with neuromuscular and syndromic scoliosis. No lateral connectors and respect sagittal balance

Abstract

Study design

One-center retrospective cohort study.

Background

Compared to the traditional iliac screw technique, the modified iliac screw technique has a lower rate of distal implant failure in the treatment of neuromuscular scoliosis patients with pelvic obliquity. However, the reasons for decreased failure with the modified iliac screw technique are controversial.

Questions/purposes

(1) Is distal implant failure, as evident by implant breakage or disconnection, more likely to occur in patients receiving the traditional iliac screw technique (PSIS) compared to the modified S2AI (MODS2) technique? (2) After controlling for relevant confounding variables, are there other identifiable risk factors for distal implant failure?

Methods

We identified patients who underwent pelvic screw fixation by three pediatric spine surgeons from January 2007 to July 2017. Based on the starting point of the iliac screws, patients were divided into two groups. Group 1 consisted of PSIS fixation with an offset connector. Group 2 consisted of modified S2AI fixation without an offset connector. Demographic, operative, and radiographic data were obtained.

Results

Cobb angle, lumbar lordosis, and pelvic obliquity were not significantly different between the two groups. Overall distal implant failure was 40/100 (40%) and significant between Group 1 PSIS 29/53 (55%) and Group 2 MODS2 11/47 (23%) (p = 0.002). No other complications were significant. Three risk factors were identified with implant failure: high pelvic incidence (17-fold increase, 95% confidence interval [CI] = 5.5 to 53.1, p < 0.001), high angle rod contour (3.8-fold increase, 95% CI = 1.2 to 11.9, p = 0.023), and use of an offset connector (3.2-fold increase, 95% CI = 1.0 to 10.3, p = 0.049). Failure did not correlate with the use of a cross-link, iliac screw diameter, or screw density. Revision surgery related to distal implant failure did not significantly differ between the two groups.

Conclusions

Compared to the use of an offset connector with PSIS fixation, MODS2 fixation had a lower rate of implant failure. Sagittal balance parameters, namely pelvic incidence and angle of rod bend, were the major risk factors for implant failure.

Level of evidence

III.

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Availability of data and materials

The datasets used and analyzed during the current study are available from the first author on reasonable request.

References

  1. 1.

    Benson ER, Thomson JD, Smith BG, Banta JV (1998) Results and morbidity in a consecutive series of patients undergoing spinal fusion for neuromuscular scoliosis. Spine (Phila Pa 1976) 23(21):2308–2317

    CAS  Article  Google Scholar 

  2. 2.

    Berven S, Wadhwa R (2018) Sagittal alignment of the lumbar spine. Neurosurg Clin N Am 29(3):331–339

    Article  Google Scholar 

  3. 3.

    Boachie-Adjei O, Lonstein JE, Winter RB, Koop S, vanden Brink K, Denis F (1989) Management of neuromuscular spinal deformities with Luque segmental instrumentation. J Bone Jt Surg Am 71(4):548–562

    CAS  Article  Google Scholar 

  4. 4.

    Broom MJ, Banta JV, Renshaw TS (1989) Spinal fusion augmented by luque-rod segmental instrumentation for neuromuscular scoliosis. J Bone Jt Surg Am 71(1):32–44

    CAS  Article  Google Scholar 

  5. 5.

    Cho KJ, Suk SI, Park SR, Kim JH, Kang SB, Kim HS, Oh SJ (2010) Risk factors of sagittal decompensation after long posterior instrumentation and fusion for degenerative lumbar scoliosis. Spine (Phila Pa 1976) 35(17):1595–1601

    Article  Google Scholar 

  6. 6.

    Desrochers-Perrault F, Aubin CE, Wang X, Schwend RM (2014) Biomechanical analysis of iliac screw fixation in spinal deformity instrumentation. Clin Biomech (Bristol, Avon) 29(6):614–621

    Article  Google Scholar 

  7. 7.

    Emami A, Deviren V, Berven S, Smith JA, Hu SS, Bradford DS (2002) Outcome and complications of long fusions to the sacrum in adult spine deformity: luque-galveston, combined iliac and sacral screws, and sacral fixation. Spine (Phila Pa 1976) 27(7):776–786

    Article  Google Scholar 

  8. 8.

    Garg S, Holland C, LaGreca J, McNair B, Erickson M (2014) Predicting failure of iliac fixation in neuromuscular spine deformity. Spine Deform 2(3):214–218

    Article  Google Scholar 

  9. 9.

    Guler UO, Cetin E, Yaman O, Pellise F, Casademut AV, Sabat MD, Alanay A, Grueso FS, Acaroglu E (2015) Sacropelvic fixation in adult spinal deformity (ASD); a very high rate of mechanical failure. Eur Spine J 24(5):1085–1091

    Article  Google Scholar 

  10. 10.

    Hoernschemeyer DG, Pashuck TD, Pfeiffer FM (2017) Analysis of the s2 alar-iliac screw as compared with the traditional iliac screw: does it increase stability with sacroiliac fixation of the spine? Spine J 17(6):875–879

    Article  Google Scholar 

  11. 11.

    Kuklo TR, Dmitriev AE, Cardoso MJ, Lehman RA Jr, Erickson M, Gill NW (2008) Biomechanical contribution of transverse connectors to segmental stability following long segment instrumentation with thoracic pedicle screws. Spine (Phila Pa 1976) 33(15):E482–E487

    Article  Google Scholar 

  12. 12.

    Lebwohl NH, Cunningham BW, Dmitriev A, Shimamoto N, Gooch L, Devlin V, Boachie-Adjei O, Wagner TA (2002) Biomechanical comparison of lumbosacral fixation techniques in a calf spine model. Spine (Phila Pa 1976) 27(21):2312–2320

    Article  Google Scholar 

  13. 13.

    Lee MC, Jarvis C, Solomito MJ, Thomson JD (2018) Comparison of S2-Alar and traditional iliac screw pelvic fixation for pediatric neuromuscular deformity. Spine J 18(4):648–654

    Article  Google Scholar 

  14. 14.

    Legaye J, Duval-Beaupère G, Hecquet J, Marty C (1998) Pelvic incidence: a fundamental pelvic parameter for three-dimensional regulation of spinal sagittal curves. Eur Spine J 7(2):99–103

    CAS  Article  Google Scholar 

  15. 15.

    Maloney WJ, Rinsky LA, Gamble JG (1990) Simultaneous correction of pelvic obliquity, frontal plane, and sagittal plane deformities in neuromuscular scoliosis using a unit rod with segmental sublaminar wires: a preliminary report. J Pediatr Orthop 10(6):742–749

    CAS  Article  Google Scholar 

  16. 16.

    McCarthy RE (1999) Management of neuromuscular scoliosis. Orthop Clin N Am 30(3):435–449

    CAS  Article  Google Scholar 

  17. 17.

    Miladi LT, Ghanem IB, Draoui MM, Zeller RD, Dubousset JF (1997) Iliosacral screw fixation for pelvic obliquity in neuromuscular scoliosis. A long-term follow-up study. Spine (Phila Pa 1976) 22(15):1722–1729

    CAS  Article  Google Scholar 

  18. 18.

    Miyanji F, Nasto LA, Sponseller PD, Shah SA, Samdani AF, Lonner B, Yaszay B, Clements DH, Narayanan U, Newton PO (2018) Assessing the risk-benefit ratio of scoliosis surgery in cerebral palsy: surgery is worth it. J Bone Jt Surg Am 100(7):556–563

    Article  Google Scholar 

  19. 19.

    Myung KS, Lee C, Skaggs DL (2015) Early pelvic fixation failure in neuromuscular scoliosis. J Pediatr Orthop 35(3):258–265

    PubMed  Google Scholar 

  20. 20.

    Neustadt JB, Shufflebarger HL, Cammisa FP (1992) Spinal fusions to the pelvis augmented by Cotrel-Dubousset instrumentation for neuromuscular scoliosis. J Pediatr Orthop 12(4):465–469

    CAS  Article  Google Scholar 

  21. 21.

    Pateder DB, Park YS, Kebaish KM, Cascio BM, Buchowski JM, Song EW, Shapiro MB, Kostuik JP (2006) Spinal fusion after revision surgery for pseudarthrosis in adult scoliosis. Spine (Phila Pa 1976) 31(11):E314–E319

    Article  Google Scholar 

  22. 22.

    Peelle MW, Lenke LG, Bridwell KH, Sides B (2006) Comparison of pelvic fixation techniques in neuromuscular spinal deformity correction: Galveston rod versus iliac and lumbosacral screws. Spine (Phila Pa 1976) 31(20):2392–8 discussion 2399

    Article  Google Scholar 

  23. 23.

    Roussouly P, Pinheiro-Franco JL (2011) Biomechanical analysis of the spino-pelvic organization and adaptation in pathology. Eur Spine J 20(Suppl 5):609–618

    Article  Google Scholar 

  24. 24.

    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(7):1384–1393

    Article  Google Scholar 

  25. 25.

    Shabtai L, Andras LM, Portman M, Harris LR, Choi PD, Tolo VT, Skaggs DL (2017) Sacral alar iliac (SAI) screws fail 75% less frequently than iliac screws in neuromuscular scoliosis. J Pediatr Orthop 37(8):e470–e475

    Article  Google Scholar 

  26. 26.

    Sink EL, Newton PO, Mubarak SJ, Wenger DR (2003) Maintenance of sagittal plane alignment after surgical correction of spinal deformity in patients with cerebral palsy. Spine (Phila Pa 1976) 28(13):1396–1403

    Google Scholar 

  27. 27.

    Sohn S, Chung CK, Kim YJ, Kim CH, Park SB, Kim H (2016) Modified iliac screw fixation: technique and clinical application. Acta Neurochir (Wien) 158(5):975–980

    Article  Google Scholar 

  28. 28.

    Sohn S, Park TH, Chung CK, Kim YJ, Jang JW, Han IB, Lee SJ (2018) Biomechanical characterization of three iliac screw fixation techniques: a finite element study. J Clin Neurosci 52:109–114

    Article  Google Scholar 

  29. 29.

    Sponseller PD, Zimmerman RM, Ko PS, Pull Ter Gunne AF, Mohamed AS, Chang TL, Kebaish KM (2010) Low profile pelvic fixation with the sacral alar iliac technique in the pediatric population improves results at two-year minimum follow-up. Spine (Phila Pa 1976) 35(20):1887–1892

    Article  Google Scholar 

  30. 30.

    Terran J, Schwab F, Shaffrey CI, Smith JS, Devos P, Ames CP, Fu KM, Burton D, Hostin R, Klineberg E, Gupta M, Deviren V, Mundis G, Hart R, Bess S, Lafage V (2013) The SRS-Schwab adult spinal deformity classification: assessment and clinical correlations based on a prospective operative and nonoperative cohort. Neurosurgery 73(4):559–568

    Article  Google Scholar 

  31. 31.

    Vaughn JJ, Schwend RM (2014) Sitting sagittal balance is different from standing balance in children with scoliosis. J Pediatr Orthop 34(2):202–207

    Article  Google Scholar 

  32. 32.

    Yilmaz E, Abdul-Jabbar A, Tawfik T, Iwanaga J, Schmidt CK, Chapman J, Blecher R, Tubbs RS, Oskouian RJ (2018) S2 Alar-iliac screw insertion: technical note with pictorial guide. World Neurosurg 113:e296–e301

    Article  Google Scholar 

  33. 33.

    Bridwell KH, Kuklo T, Edwards CC 2nd et al (2004) Sacropelvic fixation. Medtronic Sofamor Danek USA, Memphis

    Google Scholar 

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Funding

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Author information

Affiliations

Authors

Contributions

ZW: Conceptualization, methodology, data collection, radiographic readings, formal analysis and investigation, writing original draft preparation, writing review and editing, preparation of poster for IMAST, approved the version to be published journal submission. RMS: Conceptualization, methodology, formal analysis and investigation, writing original draft preparation, writing review and editing, approved the version to be published journal submission, supervision as PI, IRB application and compliance. JTA: Conceptualization, methodology, formal analysis and investigation, review and editing, drafted the work or revised it critically for important intellectual content, approved the version to be published. JAMM: Methodology, acquisition, analysis and interpretation of data, radiographic reading, formal analysis and investigation, writing review and editing, drafted the work or revised it critically for important intellectual content, approved the version to be published. NJP: Methodology, acquisition, analysis and interpretation of data, radiographic reading, writing review and editing. We thank the Medical Writing Center at Children’s Mercy Kansas City for reviewing and editing this manuscript.

Corresponding author

Correspondence to Richard M. Schwend.

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Conflict of interest

The authors declare that they have no competing interests.

Ethics approval and consent to participate

This retrospective clinical study involving human participants was in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The Human Investigation Committee (IRB) of Children’s Mercy Hospital approved this study, IRB # 000000387 on 11/9/18. This expedited study did not require signed informed patient consents.

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Wu, Z., Schwend, R.M., Anderson, J.T. et al. Iliac screw instrumentation to the pelvis in children with neuromuscular and syndromic scoliosis. No lateral connectors and respect sagittal balance. Spine Deform (2021). https://doi.org/10.1007/s43390-021-00287-6

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Keywords

  • Neuromuscular scoliosis
  • Iliac screw fixation
  • Modified iliac screw fixation
  • Offset connector
  • Sagittal balance