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There is an unmet clinical need for developing novel methods to complement and replace the current radiation-emitting imaging-based methods for the detection of loose pedicle screws as a complication after spinal fusion surgery which fail to identify a substantial amount of loose implants. In this work, we propose a new methodology and paradigm for the radiation-free, non-destructive, and easy-to-integrate detection of pedicle screw loosening based on vibroacoustic sensing. Furthermore, we propose a novel simulation technique for pedicle screw loosening, which is biomechanically validated. For the detection of a loose implant, we excite the vertebra of interest with a sine sweep vibration at the spinous process and attach a custom highly-sensitive piezo contact microphone to the screw head to capture the propagated vibration characteristics which are analyzed using a detection pipeline based on spectrogram features and a SE-ResNet-18. To validate the proposed approach, we conducted experiments using four human cadaveric lumbar spine specimens and evaluate our algorithm in a cross validation experiment. Our method reaches a sensitivity of 91.50 +- 6.58% and a specificity of 91.10 +- 2.27%. The proposed system shows great potentials for the development of alternative assessment methods for implant loosening based on vibroacoustic sensing.

Scedosporium prolificans is one of the most life-threatening fungal opportunistic pathogens due to its high resistance to common systemic antifungal agents. While a close relative of Pseudallescheria boydii, S. prolificans has a more limited geographic range being primarily found in Australia, USA and Spain. Infections have also been reported from several other European countries and from Chile. Twenty patients with Scedosporium prolificans infection or colonization from August 1993 to May 2007 were retrospectively reviewed in Germany. They had all been identified at or reported to the Reference Laboratory for Pseudallescheria/Scedosporium spp. in Berlin. Twelve of 13 patients with haematological disorders and/or on immunosuppressive therapy developed a fatal invasive scedosporiosis. Colonization of the respiratory tract was reported for one patient after heart-lung-transplantation, all six patients with cystic fibrosis and one with chronic sinusitis. Molecular studies of the S. prolificans isolates confirmed that parts of the 18S, the Internal Transcribed Spacer (ITS) regions and the D1/D2 domain of the 28S region of rDNA are monomorphic. However, sequencing of parts of the translation elongation factor EF1-alpha (EF-1alpha) and the chitin synthase (CHS-1) genes revealed the presence of three and two distinct genotypes, respectively. Two informative mutations were found in EF-1alpha and a single nucleotide exchange in the CHS-1 gene., Scedosporium prolificans is one of the most life-threatening fungal opportunistic pathogens due to its high resistance to common systemic antifungal agents. While a close relative of Pseudallescheria boydii, S. prolificans has a more limited geographic range being primarily found in Australia, USA and Spain. Infections have also been reported from several other European countries and from Chile. Twenty patients with Scedosporium prolificans infection or colonization from August 1993 to May 2007 were retrospectively reviewed in Germany. They had all been identified at or reported to the Reference Laboratory for Pseudallescheria/Scedosporium spp. in Berlin. Twelve of 13 patients with haematological disorders and/or on immunosuppressive therapy developed a fatal invasive scedosporiosis. Colonization of the respiratory tract was reported for one patient after heart-lung-transplantation, all six patients with cystic fibrosis and one with chronic sinusitis. Molecular studies of the S. prolificans isolates confirmed that parts of the 18S, the Internal Transcribed Spacer (ITS) regions and the D1/D2 domain of the 28S region of rDNA are monomorphic. However, sequencing of parts of the translation elongation factor EF1-alpha (EF-1alpha) and the chitin synthase (CHS-1) genes revealed the presence of three and two distinct genotypes, respectively. Two informative mutations were found in EF-1alpha and a single nucleotide exchange in the CHS-1 gene.