PediatrOS™ FlexTack™

Growth steering in patients with varus/valgus misalignments

Since their introduction in 2013, PediatrOS™ FlexTack™ Hemi-Epiphysiodesis Implants have enjoyed an unbroken track record of success in correcting varus and valgus misalignments, making it an alternative to implants approved for conventional applications.

The trapezoidal design of the PediatrOS™ FlexTack™ staple is closely aligned to the anatomy of the femur and tibia. Cannulated legs allow precise placement using Kirschner wires. The anatomically shaped PediatrOS™ FlexTack™ has a flexible middle zone that deforms under the forces of the growth plate while ensuring stable implant position and constant anchoring power. By adapting to ever-changing anatomic conditions, the implant helps gently and precisely correct alignment issues in paediatric and adolescent patients.

Properties / technical data

  • First flexible, anatomically shaped titanium implant designed to correct axis misalignment
  • Minimally invasive surgical technique keeps sedation time short
  • Short fluoroscopy times – 35%* reduction over plate systems
  • Parallel insertion of two 1.6 mm K-wires through cannulated implant legs allows precise placement
  • Trapezoidal design provides ideal biomechanical orientation
  • Allows immediate weight-bearing
  • Zigzagged leg shape and flexible, bending middle zone help prevent implant migration
  • PediatrOS™ FlexTack™ corrects misalignments; PediatrOS™ RigidTack™ corrects leg length differences
  • Material: TiAI6V4 ELI
  • Available in 3 sizes: 20 mm (blue), 25 mm (green), 30 mm (purple)

*Vogt, B. et al., (2015), “FlexTack™ for Temporary Hemiepiphysiodesis – Simplified implantation, reduced fluoroscopy and faster correction compared to eight-Plate™” DKOU 2015 PO25-791


Staple implant for bone growth guidance in children by means of temporary hemi-epiphysiodesis to correct axis misalignment

  • of the knee (genu varum/valgum, genu recurvatum/antecurvatum)
  • of the hip (varus)
  • of the ankle (varus/valgus, plantar flexion)
  • of the elbow (varus/valgus)
  • of the wrist (varus/valgus)

Case studies

Click here for various case studies related to the PediatrOS™ FlexTack™. If you have any questions regarding individual treatment strategies or would like more information, please contact Customer Service.

Media library

Click here for current information on the PediatrOS™ FlexTack™. Please do not hesitate to contact Customer Service for additional information.


Click here for current literature on the PediatrOS™ FlexTack™ and RigidTack™.

  • [Guided growth in children and adolescents. Correction of leg length discrepancies and leg axis deformities].
    Vogt B, Schiedel F, Rödl R.
    Orthopade. 2014 Mar;43(3):267-84. doi: 10.1007/s00132-014-2270-x.
  • [Special topics in pediatric orthopedics: options and limits of growth guidance].
    Vogt B, Horter M, Rödl R.
    Orthopade. 2014 Aug;43(8):714-24. doi: 10.1007/s00132-013-2223-9.
  • Correction of axial malalignment and leg length discrepancy of the lower extremities during growth
    Radler C, Mindler GT, Ganger R
    OUP 2016; 7/8: 433–445 DOI 10.3238/oup.2016.0433–0445
  • Temporary epiphysiodesis using the FlexTack implant (tension band) featuring a modified explantation technique.
    Koob S, Kehrer M, Hettchen M, Jansen T, Schmolders J, Placzek R.
    Oper Orthop Traumatol. 2018 Oct;30(5):359-368. doi: 10.1007/s00064-018-0553-9. Epub 2018 Jun 15.
  • Comparison of Temporary Epiphysiodesis With RigidTacks™ and Blount-Staples in a Porcine Animal Model Using Magnetic Resonance Imaging.
    Hillebrand H, Sattelberger J, Gosheger G, Frommer A, Moller-Madsen B, Rahbek O, Gottliebsen M, Abood AA, Roedl R, Vogt B.
    J Orthop Res. 2020 May;38(5):946-953. doi: 10.1002/jor.24532. Epub 2019 Nov 26.
  • Biomechanical evaluation of temporary epiphysiodesis at the femoral epiphysis using established devices from clinical practice.
    Struwe C, Walter SG, Druschel C, Bornemann R, Ploeger M, Koob S, Placzek R.
    J Mater Sci Mater Med. 2021 Apr 1;32(4):41. doi: 10.1007/s10856-021-06515-9.
  • Comparison of histomorphometric and radiographic effects of growth guidance with tension-band devices (eight-Plate and FlexTack) in a pig model.
    Sattelberger J, Hillebrand H, Gosheger G, Laufer A, Frommer A, Appelbaum S, Abood AA, Gottliebsen M, Rahbek O, Moller-Madsen B, Roedl R, Vogt B.
    Acta Orthop. 2021 Jun;92(3):364-370. doi: 10.1080/17453674.2021.1873603. Epub 2021 Jan 19.
  • [Growth modulation through hemiepiphysiodesis : Novel surgical techniques: risks and progress].
    Vogt B, Frommer A, Gosheger G, Toporowski G, Tretow H, Rödl R, Laufer A.
    Orthopade. 2021 Jul;50(7):538-547. doi: 10.1007/s00132-021-04122-8. Epub 2021 Jun 25.
  • Growth arrest: leg length correction through temporary epiphysiodesis with a novel rigid staple (RigidTack).
    Vogt B, Roedl R, Gosheger G, Frommer A, Laufer A, Kleine-Koenig MT, Theil C, Toporowski G.
    Bone Joint J. 2021 Aug;103-B(8):1428-1437. doi: 10.1302/0301-620X.103B8.BJJ-2020-1035.R4.
  • Epiphysiodesis for the treatment of tall stature and leg length discrepancy
    Madeleine Willegger, Markus Schreiner, Alexander Kolb, Reinhard Windhager, Catharina Chiari
    Wien Med Wochenschr. 2021; 171(5): 133–141. Published online 2021 Mar 18. doi: 10.1007/s10354-021-00828-8
  • Leg length discrepancies in children
    Björn Vogt, Adrien Frommer and Robert Rödl
    Springer GmbH Germany, a part of Springer Nature 2021
    Engelhardt, M. J. Raschke (ed.), European Surgical Orthopaedics and Traumatology, Springer Reference Medicine,
  • Beinlängenausgleich durch Epiphysiodese im Kindesalter – eine retrospektive Vergleichsstudie zwischen RigidTack™ und PETS
    Diplomarbeit, Bischofs, Ina (Vienna), 2021

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