Retrieval analysis of PEEK rods for posterior fusion and motion preservation

Drexel University, 3401 Market St, Suite 345, Philadelphia, PA, 19104, USA, .
European Spine Journal (Impact Factor: 2.07). 07/2013; 22(12). DOI: 10.1007/s00586-013-2920-4
Source: PubMed


The purpose of this study was to analyze explanted PEEK rod spinal systems in the context of their clinical indications. We evaluated damage to the implant and histological changes in explanted periprosthetic tissues.
12 patients implanted with 23 PEEK rods were revised between 2008 and 2012. PEEK rods were of the same design (CD Horizon Legacy, Medtronic, Memphis TN, USA). Retrieved components were assessed for surface damage mechanisms, including plastic deformation, scratching, burnishing, and fracture. Patient history and indications for PEEK rod implantation were obtained from analysis of the medical records.
11/12 PEEK rod systems were employed for fusion at one level, and motion preservation at the adjacent level. Surgical complications in the PEEK cohort included a small dural tear in one case that was immediately repaired. There were no cases of PEEK rod fracture or pedicle screw fracture. Retrieved PEEK rods exhibited scratching, as well as impressions from the set screws and pedicle screw saddles. PEEK debris was observed in two patient tissues, which were located adjacent to PEEK rods with evidence of scratching and burnishing.
This study documents the surface changes and tissue reactions for retrieved PEEK rod stabilization systems. Permanent indentations by the set screws and pedicle screws were the most prevalent observations on the surface of explanted PEEK rods.

Download full-text


Available from: Marla J Steinbeck
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A radiolucent carbon fiber-reinforced polyetheretherketone (CFR-PEEK) plate was recently introduced for fixation of proximal humerus fractures. Prospective clinical and radiographic results of patients treated with a CFR-PEEK plate are compared with those of patients treated with a conventional locking plate. Twenty-nine patients (mean age, 66 years) were treated with a CFR-PEEK plate for a 3- or 4-part proximal humerus fracture. Patients were clinically and radiographically re-examined at 6 weeks, 6 months, 12 months, and 24 months with the Simple Shoulder Test, Constant-Murley score (CMS), and Oxford Shoulder Score (OSS) as well as with simple radiographs. In addition, results were compared with a matched group of patients treated with a conventional locking plate. At the final follow-up examination at 24 months, patients achieved a mean Simple Shoulder Test score of 58%, a mean CMS of 71.3 points (range, 44-97), and a mean OSS of 27.4 points (range, 8-45). Bone union was confirmed in all patients. Compared with patients treated with the conventional locking plate, patients treated with the CFR-PEEK plate achieved significantly better results with regard to the CMS and the OSS (P = .038 and .029, respectively). Furthermore, loss of reduction with subsequent varus deformity was less frequently observed in the CFR-PEEK plate group. Fixation of proximal humerus fractures with a CFR-PEEK plate provides satisfying clinical and radiographic results after 2 years of follow-up. The results are comparable to those achieved with conventional locking plates. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
    Full-text · Article · Feb 2015 · Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The prevalence of soft tissue graft in anterior cruciate ligament (ACL) reconstruction, as well as the preference for bioabsorbable fixation continues to grow in clinical practice. This paper presents one complication related to biocomposite screw fixation used in ACL reconstruction found in clinical practice associated with a retrieval analysis of a broken biocomposite interference screw made by PLLA-HA (75% PLLA, 25% HA), arthroscopically removed from the tibial site at 8 months after ACL reconstruction with soft tissue autograft in a young patient. The fragment of broken screw was analysed in terms of surface and structural analysis following an established implant retrieval protocol. The retrieved implant surface shows cracks and breakdown signs characteristic to the final phase of resorption but incomplete probably due to biomechanical stress. The present study is important since it is one of the few cases recorded for both a composite implant as well as for an early complication, supporting the idea that the breakage of biocomposite screws should be considered during ACL reconstruction.
    Full-text · Article · Sep 2015 · MATERIALE PLASTICE