Technical ReportPotential risks of using cement-augmented screws for spinal fusion in patients with low bone quality
Introduction
As the population ages, spine surgeons are seeing an increasing number of cases with a wide variety of degenerative changes of the lumbar spine that require instrumented spinal fusion [1], [2], [3]. Surgical management in the elderly population presents some challenges. Pedicle screws that can provide three-column fixation are the most common implants used in spinal surgery, but screw performance depends on bone quality [4], [5], [6]. Accordingly, patients with osteoporosis may be predisposed to higher failure rates following posterior internal fixation system failure. Screw-loosening tests performed on patients that vary in terms of their bone quality has demonstrated that good-quality trabecular bone enhances solid fixation, whereas osteoporotic bone has a higher risk of implant failure [7], [8].
Several pedicle screw fixation techniques have been developed to improve anchoring strength and to decrease the risk of loosening [9], [10], [11], [12], but polymethyl methacrylate (PMMA)-augmented screws have been shown to be the most efficient system for strengthening pedicle screws and achieving stable fixation [13], [14], [15], [16], [17]. However, their use has raised concerns because of potential associated morbidities, such as nerve injury or vascular damage, which could be caused by cement leakage (CL). To our knowledge, no clinical studies have analyzed these potential complications. The purpose of this work was to assess the risk factors associated with the use of cement-augmented screws in spinal fusion in patients with osteoporotic vertebrae.
Section snippets
Study design
This was a retrospective study that evaluated the clinical results of surgical treatment with PMMA-augmented pedicle screws in patients with poor bone quality and various spinal diseases. A total of 313 consecutive patients (247 women, 66 men) were studied. The mean age was 73.6±7.2 years (range: 40.4–90 years), and the mean follow-up time was 29.68±14.9 months (range: 12–77 months). The patients had the following conditions: degenerative disease (223 patients), deformity (32 patients),
Results
A total of 1,043 vertebrae were instrumented with 1,780 cemented screws in 313 patients. Most of the augmented screws (84.1%) were placed at the lumbar and thoracolumbar spine, and only 42 (4%) were placed at the thoracic spine (T1–T9) (Fig. 1). The average cement volume injected per screw was 2.36 cc. Cement leakage was analyzed by radiography and by postoperative CT scans and was classified as epidural, foraminal, intradiscal, venous paravertebral, canal, or extravertebral (including
Discussion
The general population is living longer, and spine surgeons are increasingly dealing with elderly patients. Pedicle screws have been shown to be the best way to achieve fixation in the lumbar spine, but their use is controversial in patients with osteoporosis or fragile bone, because pull-out strength and fatigue failure are linearly related to BMD [7], [8]. Several techniques have been developed to ensure the attachment of screws to the fragile bone. The use of expandable screws [18], [19] has
Conclusion
Our group previously demonstrated the clinical effectiveness of using PMMA pedicle-augmented screws for the surgical treatment of patients with lumbar instability [26]. Here, in a larger series of patients, we demonstrated the safety of this technique. Our data indicate that this procedure is a good clinical choice for the surgical treatment of patients with low bone quality.
References (58)
- et al.
The biomechanics of pedicle screw augmentation with cement
Spine J
(2015) - et al.
Biomechanical analysis of different types of pedicle screw augmentation: a cadaveric and synthetic bone sample study of instrumented vertebral specimens
Med Eng Phys
(2013) - et al.
Biomechanical study of expandable pedicle screw fixation in severe osteoporotic bone comparing with conventional and cement-augmented pedicle screws
Med Eng Phys
(2014) - et al.
A titanium expandable pedicle screw improves initial pullout strength as compared with standard pedicle screws
Spine J
(2011) - et al.
Cortical bone trajectory for lumbar pedicle screws
Spine J
(2009) - et al.
Biomechanical study of pedicle screw fixation in severely osteoporotic bone
Spine J
(2004) - et al.
Basivertebral foramen could be connected with intravertebral cleft: a potential risk factor of cement leakage in percutaneous kyphoplasty
Spine J
(2014) Trabecular bone structure in lumbosacral transitional vertebrae: distribution and densities across sagittal vertebral body segments
Spine J
(2013)- et al.
Comparison of high viscosity bone cement and low viscosity bone cement vertebroplasty for severe osteoporotic vertebral compression fractures
Clin Neurol Neurosurg
(2015) - et al.
Infection after vertebroplasty or kyphoplasty. A series of nine cases and review of literature
Spine J
(2013)
Intrasite vancomycin powder for the prevention of surgical site infection in spine surgery: a systematic literature review
Spine J
Management of degenerative lumbar spinal stenosis in the elderly
Neurosurgery
A cost-utility analysis of lumbar decompression with and without fusion for degenerative spine disease in the elderly
Neurosurgery
Predictors of improvement in quality of life and pain relief in lumbar spinal stenosis relative to patient age: a study based on the Spine Tango registry
Eur Spine J
Influence of osteoporosis on fracture fixation—a systematic literature review
Osteoporos Int
Effects of bone mineral density on pedicle screw fixation
Spine
Importance of bone mineral density in instrumented spine fusions
Spine
Mechanical stability of the pedicle screw fixation systems for the lumbar spine
Spine
Caudo-cephalad loading of pedicle screws: mechanisms of loosening and methods of augmentation
Spine
A biomechanical study of two different pedicle screw methods for fixation in osteoporotic and nonosteoporotic vertebrae
J Surg Orthop Adv
Pedicle screw fixation strength: a biomechanical comparison between 4.5-mm and 5.5-mm diameter screws in osteoporotic upper thoracic vertebrae
J Surg Orthop Adv
Krag versus Caudad trajectory technique for pedicle screw insertion in osteoporotic vertebrae: biomechanical comparison and analysis
Spine
Designs and techniques that improve the pullout strength of pedicle screws in osteoporotic vertebrae: current status
Biomed Res Int
Effect of augmentation techniques on the failure of pedicle screws under cranio-caudal cyclic loading
Eur Spine J
Pedicle screw augmentation with polyethylene tape: a biomechanical study in the osteoporotic thoracolumbar spine
J Spinal Disord Tech
Assessment of different screw augmentation techniques and screw designs in osteoporotic spines
Eur Spine J
Axial pullout strength comparison of different screw designs: fenestrated screw, dual outer diameter screw and standard pedicle screw
Scoliosis
Repair of failed transpedicle screw fixation. A biomechanical study comparing polymethylmethacrylate, milled bone, and matchstick bone reconstruction
Spine
An experimental study on transpedicular screw fixation in relation to osteoporosis of the lumbar spine
Spine
Cited by (47)
A meta-analysis of complications associated with the use of cement-augmented pedicle screws in osteoporosis of spine
2021, Orthopaedics and Traumatology: Surgery and ResearchCitation Excerpt :Fenestrated screws were used in all except seven studies. Except for nine studies [11,13,14,20–22,24,25,27], all studies reported data on dual-energy X-ray absorptiometry (DEXA) scores which were < −2.5 for all included patients. The sample size of the studies varied from 15 to 313 patients.
Fenestrated pedicle screws for thoracolumbar instrumentation in patients with poor bone quality: Case series and systematic review of the literature
2021, Clinical Neurology and NeurosurgeryComparison of cement-augmented pedicle screw and conventional pedicle screw for the treatment of lumbar degenerative patients with osteoporosis
2024, European Journal of Orthopaedic Surgery and Traumatology
FDA device/drug status: approved (Cement-Augmented Screws).
Author disclosures: MM-F: Nothing to disclose. AL-H: Nothing to disclose. ARP: Nothing to disclose. FT-B: Nothing to disclose. JMD: Nothing to disclose. MDV: Nothing to disclose. MGR-A: Nothing to disclose. LA-G: Consulting fee or honorarium: Zimmer Biomet (B, Paid directly to institution/employer), pertaining to the submitted work; Speaking and/or Teaching Arrangements: Spineart (B, Paid directly to institution/employer), outside the submitted work.
The disclosure key can be found on the Table of Contents and at www.TheSpineJournalOnline.com.