Beyond the pedicle screw–a patent review

Esther P. de Kater*, Aimée Sakes, Erik Edström, Adrian Elmi-Terander, Gerald Kraan, Paul Breedveld

*Corresponding author for this work

Research output: Contribution to journalReview articlepeer-review

2 Citations (Scopus)
83 Downloads (Pure)


Purpose: This review provides an overview of the patent literature on posteriorly placed intrapedicular bone anchors. Conventional pedicle screws are the gold standard to create a fixation in the vertebra for spinal fusion surgery but may lack fixation strength, especially in osteoporotic bone. The ageing population demands new bone anchors that have an increased fixation strength, that can be placed safely, and, if necessary, can be removed without damaging the surrounding tissue. Methods: The patent search was conducted using a classification search in the Espacenet patent database. Only patents with a Cooperative Patent Classification of A61B17/70 or A61B17/7001 concerning spinal positioners and stabilizers were eligible for inclusion. The search query resulted in the identification of 731 patents. Based on preset inclusion criteria, a total of 56 unique patents on different anchoring methods were included, reviewed and categorized in this study. Results: Five unique fixation methods were identified; (1) anchors that use threading, (2) anchors that utilize a curved path through the vertebra, (3) anchors that (partly) expand, (4) anchors that use cement and (5) anchors that are designed to initiate bone ingrowth. Of the anchor designs included in this study, eight had a corresponding commercial product, six of which were evaluated in clinical trials. Conclusion: This review provides insights into worldwide patented intrapedicular bone anchors that aim to increase the fixation strength compared to the conventional pedicle screw. The identified anchoring methods and their working principles can be used for clinical decision-making and as a source of inspiration when designing novel bone anchors.

Original languageEnglish
Pages (from-to)1553-1565
JournalEuropean Spine Journal
Issue number6
Publication statusPublished - 2022


  • Bone anchor
  • Fusion
  • Mechanical design
  • Orthopaedic surgery
  • Pedicle screw
  • Spine surgery


Dive into the research topics of 'Beyond the pedicle screw–a patent review'. Together they form a unique fingerprint.

Cite this