Is coating of titanium implants effective at preventing Staphylococcus aureus infections? A meta-analysis of animal model studies.

AIM OF THE STUDY

To assess the effects of the available coating methods against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) biofilm development on titanium implants.

METHODS

We searched the MEDLINE, Embase, and CENTRAL databases until May 18, 2019, for studies that used animal models of infections to evaluate various titanium implant coating methods to prevent S. aureus infection. Twenty-seven studies were eligible for inclusion in qualitative synthesis. Of those, twenty-three were considered in pair-wise meta-analysis. In addition, subgroup analysis of implant protection strategies relative to uncoated controls was performed, and any adverse events stemming from the coating applications were reported. Quality assessment was performed using SYRCLE's risk of bias tool for animal studies.

RESULTS

Meta-analysis showed that active coating with antibiotics was favoured over uncoated controls (standardised mean differences [SMD] for MRSA and MSSA were - 2.71 [95% CI, - 4.24 to - 1.18], p = 0.0005, and - 2.5 [- 3.79 to - 1.22], p = 0.0001, respectively). Likewise, large effect sizes were demonstrated when a combination of active and conventional non-degradable passive coatings was compared with controls (SMDs for MRSA and MSSA were - 0.62 [95% CI, - 1.15 to - 0.08], p = 0.02, and - 1.93 [95% CI, - 2.87 to - 0.98], p < 0.001, respectively).

DISCUSSION/CONCLUSION: As a standalone prevention method, active titanium coating with antibiotics yielded promising results against both MSSA and MRSA. Combinations between active and non-degradable passive coatings, potentially allowing for sustained antimicrobial substance release, provided consistent hardware infection protection. Thus, we recommend that future research efforts focus on combined coating modalities against S. aureus biofilm infections in the presence of titanium implants.

SYSTEMATIC REVIEW REGISTRATION

CRD42019123462.