TY  - JOUR
A1  - Fuchs, Konrad F.
A1  - Heilig, Philipp
A1  - McDonogh, Miriam
A1  - Boelch, Sebastian
A1  - Gbureck, Uwe
A1  - Meffert, Rainer H.
A1  - Hoelscher-Doht, Stefanie
A1  - Jordan, Martin C.
T1  - Cement-augmented screw fixation for calcaneal fracture treatment: a biomechanical study comparing two injectable bone substitutes
JF  - Journal of Orthopaedic Surgery and Research
N2  - Background 
The role of cement-augmented screw fixation for calcaneal fracture treatment remains unclear. Therefore, this study was performed to biomechanically analyze screw osteosynthesis by reinforcement with either a calcium phosphate (CP)-based or polymethylmethacrylate (PMMA)-based injectable bone cement. 

Methods 
A calcaneal fracture (Sanders type IIA) including a central cancellous bone defect was generated in 27 synthetic bones, and the specimens were assigned to 3 groups. The first group was fixed with four screws (3.5 mm and 6.5 mm), the second group with screws and CP-based cement (Graftys (R) QuickSet; Graftys, Aix-en-Provence, France), and the third group with screws and PMMA-based cement (Traumacem (TM) V+; DePuy Synthes, Warsaw, IN, USA). Biomechanical testing was conducted to analyze peak-to-peak displacement, total displacement, and stiffness in following a standardized protocol. 

Results 
The peak-to-peak displacement under a 200-N load was not significantly different among the groups; however, peak-to-peak displacement under a 600- and 1000-N load as well as total displacement exhibited better stability in PMMA-augmented screw osteosynthesis compared to screw fixation without augmentation. The stiffness of the construct was increased by both CP- and PMMA-based cements. 

Conclusion 
Addition of an injectable bone cement to screw osteosynthesis is able to increase fixation strength in a biomechanical calcaneal fracture model with synthetic bones. In such cases, PMMA-based cements are more effective than CP-based cements because of their inherently higher compressive strength. However, whether this high strength is required in the clinical setting for early weight-bearing remains controversial, and the non-degradable properties of PMMA might cause difficulties during subsequent interventions in younger patients.
KW  - arthritis
KW  - bone
KW  - calcaneus
KW  - cement
KW  - fracture
KW  - fixation
KW  - osteoporosis
KW  - sanders
KW  - screw
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230336
VL  - 15
ER  - 
TY  - JOUR
A1  - Stefanakis, Mona
A1  - Bassler, Miriam C.
A1  - Walczuch, Tobias R.
A1  - Gerhard-Hartmann, Elena
A1  - Youssef, Almoatazbellah
A1  - Scherzad, Agmal
A1  - Stöth, Manuel Bernd
A1  - Ostertag, Edwin
A1  - Hagen, Rudolf
A1  - Steinke, Maria R.
A1  - Hackenberg, Stephan
A1  - Brecht, Marc
A1  - Meyer, Till Jasper
T1  - The impact of tissue preparation on salivary gland tumors investigated by Fourier-transform infrared microspectroscopy
JF  - Journal of Clinical Medicine
N2  - Due to the wide variety of benign and malignant salivary gland tumors, classification and malignant behavior determination based on histomorphological criteria can be difficult and sometimes impossible. Spectroscopical procedures can acquire molecular biological information without destroying the tissue within the measurement processes. Since several tissue preparation procedures exist, our study investigated the impact of these preparations on the chemical composition of healthy and tumorous salivary gland tissue by Fourier-transform infrared (FTIR) microspectroscopy. Sequential tissue cross-sections were prepared from native, formalin-fixed and formalin-fixed paraffin-embedded (FFPE) tissue and analyzed. The FFPE cross-sections were dewaxed and remeasured. By using principal component analysis (PCA) combined with a discriminant analysis (DA), robust models for the distinction of sample preparations were built individually for each parotid tissue type. As a result, the PCA-DA model evaluation showed a high similarity between native and formalin-fixed tissues based on their chemical composition. Thus, formalin-fixed tissues are highly representative of the native samples and facilitate a transfer from scientific laboratory analysis into the clinical routine due to their robust nature. Furthermore, the dewaxing of the cross-sections entails the loss of molecular information. Our study successfully demonstrated how FTIR microspectroscopy can be used as a powerful tool within existing clinical workflows.
KW  - formalin
KW  - fixation
KW  - tissue preparation
KW  - salivary gland neoplasia
KW  - FTIR spectroscopy
KW  - principal component analysis
KW  - discriminant analysis
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304887
SN  - 2077-0383
VL  - 12
IS  - 2
ER  -