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Screw Versus Hybrid Constructs for Flexible Thoracic Curves in Adolescent Idiopathic Scoliosis: A Prospective, Randomized Study

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Study Design

Prospective, computer-randomized design.


Compare screw and hybrid constructs in flexible, thoracic curves for adolescent idiopathic scoliosis (AIS) in a prospective randomized fashion.

Summary of Background Data

The consensus in scientific literature is that all-screw constructs correct AIS better than hooks in the lumbar and in large, stiff thoracic curves. However, debate continues whether all-screw constructs outperform hybrid constructs in small, flexible thoracic AIS. To our knowledge, this is the first prospective, randomized scoliosis study that examines measures of correction and patient satisfaction with the Scoliosis Research Society—30 (SRS-30) questionnaire.


A total of 45 enrolled AIS patients with flexible, thoracic curves were given an identification number with an associated computer-generated randomization to the hybrid (n = 22) or screw group (n = 23). The treating surgeon received the randomization 2—3 days before surgery. Data including major Cobb (MC), truncal rotation (TR), rib index (RI), secondary curve (SC), and SRS-30 questionnaire were collected preoperatively and postoperatively at 4 weeks and 3, 6, 12, and 24 months.


Thirty-seven patients in the hybrid (n = 18) and screw (n = 19) groups completed the study with a mean follow-up of 26 months (range, 24—49 months). Hybrid versus screw group means for preoperative, postoperative, and final follow-up were: MC 58° ± 8° versus 55° ± 6°, 18° ± 8° versus 15° ± 7°, and 23°± 8° versus 14° ± 6°; TR 14° ± 6° versus 16° ± 4°, 10° ± 5° versus 7° ± 3°, and 11° ± 5° versus 7° ± 4°; RI 3.0° ± 1.2° versus 3.4° ± 1.4°, 2.5° ± 0.7° versus 1.8° ± 0.6°, and 2.5° ± 0.8° versus 2.0° ± 0.5°; SC 35° ± 13° versus 31° ± 8°, 13° ± 11° versus 7° ± 9°, and 13° ± 12° versus 7° ± 7°; and SRS-30 3.9 ± 0.2 versus 3.9 ± 0.2, 4.1 ± 0.4 versus 4.0 ± 0.3, and 4.1 ± 0.3 versus 4.0 ± 0.2.


Intergroup preoperative and early postoperative values were comparable (p >.05). At final follow-up, owing to loss of correction in the hybrid group, differences in MC (9°; p =.000), RI (0.54; p =.016), and TR (4°; p =.039) correction were statistically significant as SC trended toward significance (6°; p =.052). All-screw constructs outperformed hybrid constructs, especially over time. No differences in SRS-30 scores occurred between groups.

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  1. [1]

    Suk SI, Lee CK, Chung SS. Comparison of Cotrel-Dubousset pedicle screws and hooks in the treatment of idiopathic scoliosis. Int Orthop 1994;18:341–6.

  2. [2]

    Suk SI, Lee CK, Kim WJ, et al. Segmental pedicle screw fixation in the treatment of thoracic idiopathic scoliosis. Spine (Phila Pa 1976) 1995;20:1399–405.

  3. [3]

    Liljenqvist UR, Halm HF, Link TM. Pedicle screw instrumentation of the thoracic spine in idiopathic scoliosis. Spine (Phila Pa 1976) 1997;22:2239–45.

  4. [4]

    Barr SJ, Schuette AM, Emans JB. Lumbar pedicle screws versus hooks: results in double major curves in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 1997;22:1369–79.

  5. [5]

    Suk SI, Kim WJ, Kim JH, et al. Restoration of thoracic kyphosis in the hypokyphotic spine: a comparison between multiple-hook and segmental pedicle screw fixation. J Spinal Disord 1999;12:489–95.

  6. [6]

    Liljenqvist U, Lepsien U, Hackenberg L, et al. Comparative analysis of pedicle screw and hook instrumentation in posterior correction and fusion of idiopathic thoracic scoliosis. Eur Spine J 2002;11:336–43.

  7. [7]

    Kim YJ, Lenke LG, Cho SK, et al. Comparative analysis of pedicle screw versus hook instrumentation in posterior spinal fusion of adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 2004;29:2040–8.

  8. [8]

    Mulpuri K, Perdious A, Reilly CW. Evidence-based medicine analysis of all pedicle screw constructs in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 2007;32:S109–14.

  9. [9]

    Vora V, Crawford A, Babekhir N, et al. A pedicle screw construct gives an enhanced posterior correction of adolescent idiopathic scoliosis when compared with other constructs: myth or reality. Spine (Phila Pa 1976) 2007;32:1869–74.

  10. [10]

    Lenke LG, Richards S, Stanitski CL. Debate: resolved, a 55° right thoracic adolescent idiopathic scoliotic curve should be treated by posterior spinal fusion and segmental instrumentation using thoracic pedicle screws. J Pediatr Orthop 2004;24:29–41.

  11. [11]

    Arlet V, Ouellet JA, Shilt J, et al. Subjective evaluation of treatment outcomes of instrumentation with pedicle screws or hybrid constructs in Lenke Type 1 and 2 adolescent idiopathic scoliosis: what happens when judges are blinded to the instrumentation? Eur Spine J 2009;18:127–35.

  12. [12]

    Hamill CL, Lenke LG, Bridwell KH, et al. The use of pedicle screw fixation to improve correction in the lumbar spine of patients with idiopathic scoliosis: is it warranted? Spine (Phila Pa 1976) 1996;21:1241–9.

  13. [13]

    Clements DH, Betz RR, Newton PO, et al. Correlation of scoliosis curve correction with the number and type of fixation anchors. Spine (Phila Pa 1976) 2009;34:2147–50.

  14. [14]

    Dobbs MB, Lawrence LG, Yongjung JK, et al. Selective posterior thoracic fusions for adolescent idiopathic scoliosis: comparison of hooks versus pedicle screws. Spine (Phila Pa 1976) 2006;31:2400–4.

  15. [15]

    Arlet V, Liang J, Ouellet J. Is there a need for anterior release for 70-90° thoracic curves in adolescent scoliosis? Eur Spine J 2004;13:740–55.

  16. [16]

    Di Silvestre M, Bakaloudis G, Lolli F, et al. Posterior fusion only for thoracic adolescent idiopathic scoliosis of more than 80°: pedicle screws versus hybrid instrumentation. Eur Spine J 2008;17:1336–49.

  17. [17]

    Luhmann SJ, Lenke LG, Yongjung JK, et al. Thoracic adolescent idiopathic scoliosis curves between 70° and 100°: is anterior release necessary? Spine (Phila Pa 1976) 2005;30:2061–7.

  18. [18]

    Ledonio CGT, Polly DW, Vitale MG, et al. Pediatric pedicle screws: comparative effectiveness and safety: a systematic literature review from the Scoliosis Research Society and the Pediatric Orthopaedic Society of North America Task Force. J Bone Joint Surg Am 2011;93:1227–34.

  19. [19]

    Wu X, Shuhua Y, Weihua X, et al. Comparative intermediate and long-term results of pedicle screw and hook instrumentation in posterior correction and fusion of idiopathic thoracic scoliosis. J Spinal Disord Tech 2010;23:467–73.

  20. [20]

    Karatoprak O, Unay K, Tezer M, et al. Comparative analysis of pedicle screw versus hybrid instrumentation in adolescent idiopathic scoliosis surgery. Int Orthop 2008;32:523–8.

  21. [21]

    Lowenstein JE, Matsumoto H, Vitale MG, et al. coronal and sagittal plane correction in adolescent idiopathic scoliosis: a comparison between all pedicle screw versus hybrid thoracic hook lumbar screw constructs. Spine (Phila Pa 1976) 2007;32:448–52.

  22. [22]

    Delorme S, Labelle H, Aubin CE, et al. A three-dimensional radiographic comparison of Cotrel-Dubousset and Colorado instrumentation for the correction of idiopathic scoliosis. Spine (Phila Pa 1976) 2000;25:205–10.

  23. [23]

    Storer SK, Vitale MG, Hyman JE, et al. correction of adolescent idiopathic scoliosis using thoracic pedicle screw fixation versus hook constructs. J Pediatr Orthop 2005;25:415–9.

  24. [24]

    Murrell GA, Coonrad RW, Moorman CT, et al. An assessment of the reliability of the scoliometer. Spine (Phila Pa 1976) 1993;18:709–12.

  25. [25]

    Bonagamba GH, Coelho DM, Oliveira AS. Inter and intra-rater reliability of the scoliometer. Rev Bras Fisioter 2010;14:432–8.

  26. [26]

    Luhmann SJ, Lenke LG, Erickson M. Correction of moderate (< 70 degrees) Lenke 1A and 2A curve patterns: comparison of hybrid and all-pedicle screw systems at 2-year follow-up. J Pediatr Orthop 2012;32:253–8.

  27. [27]

    Lykissas MG, Sharma V, Crawford AH. Assessment of rib hump deformity correction in adolescent idiopathic scoliosis with or without costoplasty using the double rib contour sign. J Spinal Disord Tech 2012 Sep 28 [Epub ahead of print].

  28. [28]

    Smucny M, Lubicky JP, Sander JO, et al. Patient self-assessment of appearance is improved more by all pedicle screw than by hybrid constructs in surgical treatment of adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 2011;36:28–54.

  29. [29]

    Lubicky JP, Hanson JE, Riley EH, et al. Instrumentation constructs in pediatric patients undergoing deformity correction correlated with scoliosis research society scores. Spine (Phila Pa 1976) 2011;36:1692–700.

  30. [30]

    Kuklo TR, Potter BK, Lenke LG, et al. Surgical revision rates of hooks versus hybrid screws versus combined anteroposterior spinal fusion for adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 2007;32:2258–64.

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Author information

Correspondence to Lawrence L. Haber MD.

Additional information

Author disclosures: LLH (grants from Depuy Spine (grant no: 2005CO24), during the conduct of the study), JDH (grants from Depuy Spine (grant no: 2005CO24), during the conduct of the study), EDW (grants from Depuy Spine (grant no: 2005CO24), during the conduct of the study), RMR (grants from Depuy Spine (grant no: 2005CO24), during the conduct of the study), PBW (grants from Depuy Spine, during the conduct of the study).

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Haber, L.L., Hughes, J.D., Womack, E.D. et al. Screw Versus Hybrid Constructs for Flexible Thoracic Curves in Adolescent Idiopathic Scoliosis: A Prospective, Randomized Study. Spine Deform 2, 367–373 (2014). https://doi.org/10.1016/j.jspd.2014.05.005

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  • AIS
  • Screw
  • Hybrid
  • Flexible
  • Thoracic