Pedicle screw loosening is correlated to chronic subclinical deep implant infection: a retrospective database analysis

  • Lukas Leitner
  • Isabella Malaj
  • Patrick Sadoghi
  • Florian Amerstorfer
  • Mathias Glehr
  • Klaus Vander
  • Andreas Leithner
  • Roman Radl
Original Article



Spinal fusion is used for treatment of spinal deformities, degeneration, infection, malignancy, and trauma. Reduction of motion enables osseous fusion and permanent stabilization of segments, compromised by loosening of the pedicle screws (PS). Deep implant infection, biomechanical, and chemical mechanisms are suspected reasons for loosening of PS. Study objective was to investigate the frequency and impact of deep implant infection on PS loosening.


Intraoperative infection screening from wound and explanted material sonication was performed during revision surgeries following dorsal stabilization. Case history events and factors, which might promote implant infections, were included in this retrospective survey.


110 cases of spinal metal explantation were included. In 29.1% of revision cases, infection screening identified a germ, most commonly Staphylococcus (53.1%) and Propionibacterium (40.6%) genus. Patients screened positive had a significant higher number of previous spinal operations and radiologic loosening of screws. Patients revised for adjacent segment failure had a significantly lower rate of positive infection screening than patients revised for directly implant associated reasons. Removal of implants that revealed positive screening effected significant pain relief.


Chronic implant infection seems to play a role in PS loosening and ongoing pain, causing revision surgery after spinal fusion. Screw loosening and multiple prior spinal operations should be suspicious for implant infection after spinal fusion when it comes to revision surgery.

Graphical abstract

These slides can be retrieved under Electronic Supplementary Material.


Spinal fusion Pedicle screw Implant infection Implant loosening 



No funding was obtained for this manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare no competing financial interests.

Ethics statement

This study was approved by the Institutional Ethical Review Board (Reference number: 28-210 ex 15/16).

Supplementary material

586_2018_5592_MOESM1_ESM.pptx (975 kb)
Supplementary material 1 (PPTX 975 kb)


  1. 1.
    Hartl R, Theodore N, Dickman CA, Sonntag HKV (2004) Technique of thoracic pedicle screw fixation for trauma. Oper Tech Neurosurg 7:22–30CrossRefGoogle Scholar
  2. 2.
    Cho W, Cho SK, Wu C (2010) The biomechanics of pedicle screw-based instrumentation. J Bone Joint Surg Br 92:1061–1065CrossRefPubMedGoogle Scholar
  3. 3.
    El Saman A et al (2013) Reduced loosening rate and loss of correction following posterior stabilization with or without PMMA augmentation of pedicle screws in vertebral fractures in the elderly. Eur J Trauma Emerg Surg 39(5):455–460CrossRefPubMedGoogle Scholar
  4. 4.
    Weiser L et al (2017) Insufficient stability of pedicle screws in osteoporotic vertebrae: biomechanical correlation of bone mineral density and pedicle screw fixation strength. Eur Spine J 26(11):2891–2897CrossRefPubMedGoogle Scholar
  5. 5.
    Pearson HB et al (2017) Intraoperative biomechanics of lumbar pedicle screw loosening following successful arthrodesis. J Orthop Res 35(12):2673–2681CrossRefPubMedGoogle Scholar
  6. 6.
    Huiskes R, Weinans H, van Rietbergen B (1992) The relationship between stress shielding and bone resorption around total hip stems and the effects of flexible materials. Clin Orthop Relat Res 274:124–134Google Scholar
  7. 7.
    Schatzker J, Horne JG, Sumner-Smith G (1975) The effect of movement on the holding power of screws in bone. Clin Orthop Relat Res 111:257–262CrossRefGoogle Scholar
  8. 8.
    Villa T, La Barbera L, Galbusera F (2014) Comparative analysis of international standards for the fatigue testing of posterior spinal fixation systems. Spine J 14:695–704CrossRefPubMedGoogle Scholar
  9. 9.
    Hallab NJ, Cunningham BW, Jacobs JJ (2003) Spinal implant debris-induced osteolysis. Spine (Phila Pa 1976) 28:S125–S138CrossRefGoogle Scholar
  10. 10.
    Galbusera F et al (2015) Pedicle screw loosening: a clinically relevant complication? Eur Spine J 24(5):1005–1016CrossRefPubMedGoogle Scholar
  11. 11.
    Kimura H, Shikata J, Odate S, Soeda T (2017) Pedicle screw fluid sign: an indication on magnetic resonance imaging of a deep infection after posterior spinal instrumentation. Clin Spine Surg 30(4):169–175CrossRefPubMedGoogle Scholar
  12. 12.
    Del Pozo JL, Patel R (2009) Clinical practice. Infection associated with prosthetic joints. N Engl J Med 361(8):787–794CrossRefPubMedPubMedCentralGoogle Scholar
  13. 13.
    Pajarinen J, Jamsen E, Konttinen YT, Goodman SB (2014) Innate immune reactions in septic and aseptic osteolysis around hip implants. J Long Term Eff Med Implants 24(4):283–296CrossRefPubMedPubMedCentralGoogle Scholar
  14. 14.
    Moermann M et al (2008) Lipopolysaccharides (LPS) induce the differentiation of human monocytes to osteoklasts in a tumour necrosis factor (TNF) α-dependent manner: a link between infection and pathological bone resorption. Mol Immunol 45:3330–3337CrossRefGoogle Scholar
  15. 15.
    Rienmüller A, Borens O (2016) Propionibacterium prosthetic joint infection: experience from a retrospective database analysis. Eur J Orthop Surg Traumatol 26(4):429–434CrossRefPubMedPubMedCentralGoogle Scholar
  16. 16.
    Morawietz L et al (2009) Twenty-three neutrophil granulocytes in 10 high-power fields is the best histopathological threshold to differentiate between aseptic and septic endoprosthesis loosening. Histopathology 54(7):847–853CrossRefPubMedGoogle Scholar
  17. 17.
    Trampuz A et al (2007) Sonication of removed hip and knee prostheses for diagnosis of infection. N Engl J Med 357(7):654–663CrossRefPubMedGoogle Scholar
  18. 18.
    Hart A et al (2014) Blood transfusion in primary total hip and knee arthroplasty. Incidence, risk factors, and thirty-day complication rates. J Bone Joint Surg Am 96:1945–1951CrossRefPubMedGoogle Scholar
  19. 19.
    Hahn F, Zbinden R, Min K (2005) Late implant infections caused by Propionibacterium acnes in scoliosis surgery. Eur Spine J 14(8):783–788CrossRefPubMedPubMedCentralGoogle Scholar
  20. 20.
    Gristina AG, Costerton JW (1985) Bacterial adherence to biomaterials and tissue. The significance of its role in clinical sepsis. J Bone Joint Surg Am 67(2):264–273CrossRefPubMedGoogle Scholar
  21. 21.
    Johns BE, Purdy KJ, Tucker NP, Maddocks SE (2015) Phenotypic and genotypic characteristics of small colony variants and their role in chronic infection. Microbiol Insights. 8:15–23CrossRefPubMedPubMedCentralGoogle Scholar
  22. 22.
    Richards BS (1995) Delayed infections following posterior spinal instrumentation for the treatment of idiopathic scoliosis. J Bone Joint Surg Am 77(4):524–529CrossRefPubMedGoogle Scholar
  23. 23.
    Clark CE, Shufflebarger HL (1999) Late-developing infection in instrumented idiopathic scoliosis. Spine (Phila Pa 1976) 24(18):1909–1912CrossRefGoogle Scholar
  24. 24.
    Mhaidli HH, Der-Boghossian AH, Haidar RK (2013) Propionibacterium acnes delayed infection following spinal surgery with instrumentation. Musculoskelet Surg. 97(1):85–87CrossRefPubMedGoogle Scholar
  25. 25.
    Bose B (2003) Delayed infection after instrumented spine surgery: case reports and review of the literature. Spine J 3(5):394–399CrossRefPubMedGoogle Scholar
  26. 26.
    McLorinan GC, Glenn JV, McMullan MG, Patrick S (2005) Propionibacterium acnes wound contamination at the time of spinal surgery. Clin Orthop Relat Res 437:67–73CrossRefGoogle Scholar
  27. 27.
    Kang DG, Holekamp TF, Wagner SC, Lehman RA Jr (2015) Intrasite vancomycin powder for the prevention of surgical site infection in spine surgery: a systematic literature review. Spine J 15(4):762–770CrossRefPubMedGoogle Scholar
  28. 28.
    Fritzell P, Bergström T, Welinder-Olsson C (2004) Detection of bacterial DNA in painful degenerated spinal discs in patients without signs of clinical infection. Eur Spine J 13:702–706CrossRefPubMedPubMedCentralGoogle Scholar
  29. 29.
    Albert HB et al (2013) Does nuclear tissue infected with bacteria following disc herniations lead to Modic changes in the adjacent vertebrae? Eur Spine J 22(4):690–696CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Lukas Leitner
    • 1
  • Isabella Malaj
    • 1
  • Patrick Sadoghi
    • 1
  • Florian Amerstorfer
    • 1
  • Mathias Glehr
    • 1
  • Klaus Vander
    • 2
  • Andreas Leithner
    • 1
  • Roman Radl
    • 1
  1. 1.Department of Orthopedics and TraumaMedical University of GrazGrazAustria
  2. 2.Institute of Microbiology and HygieneMedical University of GrazGrazAustria

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