Surgical management of moderate adolescent idiopathic scoliosis with a fusionless posterior dynamic deformity correction device: interim results with bridging 5–6 disc levels at 2 or more years of follow-up

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  • 1 Israel Spine Center, Assuta Hospital, Tel Aviv, Israel;
  • 2 IWK Health Centre Halifax, Nova Scotia, Canada;
  • 3 Mount Sinai Hospital Icahn School of Medicine, New York, New York; and
  • 4 Institute for Spine & Scoliosis, Lawrenceville, New Jersey

OBJECTIVE

A posterior dynamic deformity correction (PDDC) system was used to correct adolescent idiopathic scoliosis (AIS) without fusion. The preliminary outcomes of bridging only 3–4 discs in patients with variable curve severity have previously been reported. This paper examines a subgroup of patients with the authors’ proposed current indications for this device who were also treated with a longer construct.

METHODS

Inclusion criteria included a single AIS structural curve between 40° and 60°, curve flexibility ≤ 30°, PDDC spanning 5–6 levels, and minimum 2-year follow-up. A retrospective review was conducted and demographic and radiographic data were recorded. A successful outcome was defined as a curve magnitude of ≤ 30° at final follow-up. Any serious adverse events and reoperations were recorded.

RESULTS

Twenty-two patients who met the inclusion criteria were operated on with the PDDC in 5 medical centers. There were 19 girls and 3 boys, aged 13–17 years, with Risser grades ≥ 2. Thirteen had Lenke type 1 curves and 9 had type 5 curves. The mean preoperative curve was 47° (range 40°–55°). At a minimum of 2 years’ follow-up, the mean major curve measured 25° (46% correction, p < 0.05). In 18 (82%) of 22 patients, the mean final Cobb angle measured ≤ 30° (range 15°–30°). Trunk shift was corrected by 1.5 cm (range 0.4–4.3 cm). The mean minor curve was reduced from 27° to 17° at final follow-up (35% correction, p < 0.05). For Lenke type 1 patterns, the mean 2D thoracic kyphosis was 24° preoperatively versus 27° at final follow-up (p < 0.05), and for Lenke type 5 curves, mean lumbar lordosis was 47° preoperatively versus 42° at final follow-up (p < 0.05). The mean preoperative Scoliosis Research Society-22 questionnaire score improved from 2.74 ± 0.3 at baseline to 4.31 ± 0.4 at 2 years after surgery (p < 0.0001). The mean preoperative self-image score and satisfaction scores improved from preoperative values, while other domain scores did not change significantly. Four patients (18%) underwent revision surgery because of nut loosening (n = 2), pedicle screw backup (n = 1), and ratchet malfunction (n = 1).

CONCLUSIONS

In AIS patients with a single flexible major curve up to 60°, the fusionless PDDC device achieved a satisfactory result as 82% had residual curves ≤ 30°. These findings suggest that the PDDC device may serve as an alternative to spinal fusion in select patients.

ABBREVIATIONS AIS = adolescent idiopathic scoliosis; IMAST = International Meeting on Advanced Spine Techniques; PDDC = posterior dynamic deformity correction; SRS-22 = Scoliosis Research Society-22.

Contributor Notes

Correspondence Yizhar Floman: Assuta Hospital, Tel Aviv, Israel. yizharfloman@gmail.com.

INCLUDE WHEN CITING Published online January 10, 2020; DOI: 10.3171/2019.11.SPINE19827.

Disclosures Dr. Floman is a co-founder of ApiFix. Dr. El-Hawary reports being a consultant for Medtronic Canada, DePuy Synthes Spine, ApiFix Ltd., Globus Medical, and Wishbone Medical, and holding stock options in ApiFix Ltd. and Wishbone Medical. Dr. Millgram reports having direct stock ownership in ApiFix. Dr. Lonner reports being a consultant to DePuy Synthes, Ethicon, Zimmer Biomet, and ApiFix; having direct stock ownership in Spine Search and Paradigm Spine; having private investments in Paradigm Spine; serving on the Scientific Advisory Board, Speaker’s Bureau, and receiving royalties from DePuy Synthes for the development of the Expedium Plus Implant System; serving as a Scientific Advisory Board Member for ApiFix; serving on the Board of Directors of Spine Search and the Setting Scoliosis Straight Foundation; and serving on the Speaker’s Bureau for K2M. Dr. Betz reports being a consultant for ApiFix, DePuy Synthes Spine, Globus Medical, SpineGuard, and Wishbone Medical; having stock options in Abyrx, ApiFix, Electrocore, Medovex, Orthobond, SpineGuard, and Wishbone Medical; receiving royalties from DePuy Synthes Spine, Globus Medical, SpineGuard, and Thieme Medical Publishers; serving on the Speakers Bureau for DePuy Synthes Spine and Globus Medical; and having a child who is employed by DePuy Synthes Spine.

  • 1

    Arnin U, El-Hawary R, Betz RR, Lonner BS, Floman Y: Preclinical bench testing on a novel posterior dynamic scoliosis correction device for scoliosis. Spine Deform 7:203212, 2019

    • Search Google Scholar
    • Export Citation
  • 2

    Asher M, Min Lai S, Burton D, Manna B: Scoliosis research society-22 patient questionnaire: responsiveness to change associated with surgical treatment. Spine (Phila Pa 1976) 28:7073, 2003

    • Search Google Scholar
    • Export Citation
  • 3

    Carreon LY, Sanders JO, Diab M, Sucato DJ, Sturm PF, Glassman SD: The minimum clinically important difference in Scoliosis Research Society-22 Appearance, Activity, And Pain domains after surgical correction of adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 35:20792083, 2010

    • Search Google Scholar
    • Export Citation
  • 4

    de Kleuver M, Lewis SJ, Germscheid NM, Kamper SJ, Alanay A, Berven SH, : Optimal surgical care for adolescent idiopathic scoliosis: an international consensus. Eur Spine J 23:26032618, 2014

    • Search Google Scholar
    • Export Citation
  • 5

    El-Hawary R, Betz RR, Lonner BS, Floman Y: Optimization of outcomes with a novel fusionless posterior dynamic deformity correction (PDDC) device for adolescent idiopathic scoliosis: learning curve drives indications, in IMAST 2019 Amsterdam. 26th International Meeting on Advanced Spine Techniques. Final Program. Milwaukee: Scoliosis Research Society, 2019, p 158 (Abstract 180)

    • Search Google Scholar
    • Export Citation
  • 6

    Engsberg JR, Lenke LG, Uhrich ML, Ross SA, Bridwell KH: Prospective comparison of gait and trunk range of motion in adolescents with idiopathic thoracic scoliosis undergoing anterior or posterior spinal fusion. Spine (Phila Pa 1976) 28:19932000, 2003

    • Search Google Scholar
    • Export Citation
  • 7

    Floman Y, Burnei G, Gavriliu S, Anekstein Y, Straticiuc S, Tunyogi-Csapo M, : Surgical management of moderate adolescent idiopathic scoliosis with ApiFix®: a short periapical fixation followed by post-operative curve reduction with exercises. Scoliosis 10:49, 2015

    • Search Google Scholar
    • Export Citation
  • 8

    Floman Y, Gavriliu S, Potaczek T, Zarzycki D, Desai B, Tunyogi-Csapo M, : A new posterior dynamic device for correction of moderate adolescent idiopathic scoliosis: 27 cases with two to five years of follow up, in IMAST 2018 Los Angeles. 25th International Meeting on Advanced Spine Techniques. Final Program. Milwaukee: Scoliosis Research Society, 2018, pp 101102 (Abstract 61)

    • Search Google Scholar
    • Export Citation
  • 9

    Holewijn RM, de Kleuver M, van der Veen AJ, Emanuel KS, Bisschop A, Stadhouder A, : A novel spinal implant for fusionless scoliosis correction: a biomechanical analysis of the motion preserving properties of a posterior periapical concave distraction device. Global Spine J 7:400409, 2017

    • Search Google Scholar
    • Export Citation
  • 10

    Larson AN, Fletcher ND, Daniel C, Richards BS: Lumbar curve is stable after selective thoracic fusion for adolescent idiopathic scoliosis: a 20-year follow-up. Spine (Phila Pa 1976) 37:833839, 2012

    • Search Google Scholar
    • Export Citation
  • 11

    Lenke LG, Betz RR, Bridwell KH, Harms J, Clements DH, Lowe TG: Spontaneous lumbar curve coronal correction after selective anterior or posterior thoracic fusion in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 24:16631672, 1999

    • Search Google Scholar
    • Export Citation
  • 12

    Newton PO, Fricka KB, Lee SS, Farnsworth CL, Cox TG, Mahar AT: Asymmetrical flexible tethering of spine growth in an immature bovine model. Spine (Phila Pa 1976) 27:689693, 2002

    • Search Google Scholar
    • Export Citation
  • 13

    Newton PO, Kluck DG, Saito W, Yaszay B, Bartley CE, Bastrom TP: Anterior spinal growth tethering for skeletally immature patients with scoliosis: a retrospective look two to four years postoperatively. J Bone Joint Surg Am 100:16911697, 2018

    • Search Google Scholar
    • Export Citation
  • 14

    Pesenti S, Jouve JL, Morin C, Wolff S, Sales de Gauzy J, Chalopin A, : Evolution of adolescent idiopathic scoliosis: results of a multicenter study at 20 years’ follow-up. Orthop Traumatol Surg Res 101:619622, 2015

    • Search Google Scholar
    • Export Citation
  • 15

    Robitaille M, Aubin CE, Labelle H: Intra and interobserver variability of preoperative planning for surgical instrumentation in adolescent idiopathic scoliosis. Eur Spine J 16:16041614, 2007

    • Search Google Scholar
    • Export Citation
  • 16

    Rohlmann A, Graichen F, Weber U, Bergmann G: 2000 Volvo Award winner in biomechanical studies: Monitoring in vivo implant loads with a telemetrized internal spinal fixation device. Spine (Phila Pa 1976) 25:29812986, 2000

    • Search Google Scholar
    • Export Citation
  • 17

    Samdani AF, Ames RJ, Kimball JS, Pahys JM, Grewal H, Pelletier GJ, : Anterior vertebral body tethering for idiopathic scoliosis: two-year results. Spine (Phila Pa 1976) 39:16881693, 2014

    • Search Google Scholar
    • Export Citation
  • 18

    Souder C, Newton PO, Shah SA, Lonner BS, Bastrom TP, Yaszay B: Factors in surgical decision making for thoracolumbar/lumbar AIS: it’s about more than just the curve magnitude. J Pediatr Orthop 37:e530e535, 2017

    • Search Google Scholar
    • Export Citation
  • 19

    Udoekwere UI, Krzak JJ, Graf A, Hassani S, Tarima S, Riordan M, : Effect of lowest instrumented vertebra on trunk mobility in patients with adolescent idiopathic scoliosis undergoing posterior spinal fusion. Spine Deform 2:291300, 2014

    • Search Google Scholar
    • Export Citation
  • 20

    Weinstein SL, Dolan LA, Cheng JCY, Danielsson A, Morcuende JA: Adolescent idiopathic scoliosis. Lancet 371:15271537, 2008

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