Jess Gerrit Snedeker


Last Name

Snedeker

First Name

Jess Gerrit

ORCID

0000-0002-8115-0275

Organisational unit

03822 - Snedeker, Jess G. / Snedeker, Jess G.

Search Results

Publications1 - 10 of 321
  • Functional microimaging
    Item type: Journal Article
    Voide, R.; van Lenthe, G. Harry; Schneider, P.; et al. (2006)
    Proceedings of SPIE
  • Intervertebral disc degeneration relates to biomechanical changes of spinal ligaments
    Item type: Journal Article
    Cornaz, Frédéric; Widmer, Jonas; Farshad-Amacker, Nadja A.; et al. (2021)
    The Spine Journal
    BACKGROUND CONTEXT: The ligamentum flavum (LF), the inter- and supraspinous ligament (ISL&SSL) and the intertransverse ligament (ITL) are relevant spinal structures for segmental stability. The biomechanical effect of degeneration and aging on their biomechanical properties remains largely unknown. PURPOSE: The aim of this study was to assess the material properties of the ITL, ISL&SSL and LF and to correlate parameters of biomechanical function with LF-thickness, intervertebral disc (IVD) degeneration and age. STUDY DESIGN: Biomechanical cadaveric study. METHODS: MRI- and CT-scans of 50 human lumbar segments (Th12-L5) were used to assess the ISL (acc. to Keorochana), the grade of IVD degeneration (acc. to Pfirrmann) and to quantify LF-thickness. The ITL, ISL&SSL and LF were resected in the neutral position of the spinal segment with a specifically developed method to conserve initial strain. Ramp to failure testing was performed (0.5 mm/s) to record initial tension, slack length, stiffness and ultimate strength. The relationship between the biomechanical characteristics and age and radiological parameters were analyzed. There are no study-specific conflicts of interest and no external funding was received for this study. RESULTS: With aging, a significant reduction in initial tension (r=-0.5, p<.01) and ultimate strength (r=-0.41, p<.01) of the LF was observed, while the effect on LF-stiffness and the characteristics of the other ligaments was non-significant. IVD-degeneration was correlated with a significant reduction in stiffness (r=-0.47, p=.001; r=-0.36, p=.01) and ultimate strength (r=-0.3, p=.04; r=-0.36, p=.01) of the LF and ISL&SSL respectively and a significant reduction in initial tension (r=-0.4, p<.01) of the LF. For the ITL, no significant correlation was observed. Comparing Pfirrman 2 to 5, this reduction was 40% to 80% for stiffness 60% to 70% for ultimate strength and 88% for initial tension of the LF. ISL&SSL-stiffness between Kerorochana grade A and D differed significantly (p=.03), while all other comparisons were non-significant (p>.05). LF-thickness did not correlate with the biomechanical properties of the LF (p>.05). CONCLUSIONS: Aging is primarily related to biomechanical changes to the LF. IVD-degeneration is related to a relevant reduction in stiffness and ultimate strength of the LF and ISL&SSL, with a similar trend for the ITL. The ISL-specific Keorochana grading system provides only minimal biomechanical information and LF-thickness does not provide biomechanical information. CLINICAL SIGNIFICANCE: Patient age and the degenerative state of the IVD can be used to evaluate the biomechanical characteristics of the dorsal spinal ligaments, which can be helpful in selecting the optimal surgical procedure (e.g. in decompression surgery) for a specific situation.
  • Macrophage Polarization by Titanium Dioxide (TiO2) Particles: Size Matters
    Item type: Journal Article
    Schoenenberger, Angelina D.; Schipanski, Angela; Malheiro, Vera; et al. (2016)
    ACS Biomaterials Science & Engineering
  • Fibronectin Fragments Modulate Expression of Focal Adhesion Elements to Enhance Osteogenic Differentiation of Bone Marrow Stromal Cells
    Item type: Conference Poster
    Sharma, Ram; Snedeker, Jess Gerrit (2011)
    ORS Transactions
  • A predictive model of cytoskeleton reorganization during initial cell adhesion to bioactive substrate
    Item type: Conference Poster
    Loosli, Y.M.; Snedeker, Jess Gerrit (2010)
  • Helical Cutting as a New Method for Tendon-Lengthening in Continuity
    Item type: Journal Article
    Farshad, Mazda; Gerber, Christian; Snedeker, Jess Gerrit; et al. (2011)
    The Journal of Bone and Joint Surgery
  • A method for the design of a heel cushioning insole
    Item type: Conference Paper
    Snedeker, Jess Gerrit; Cavanagh, Peter R. (1999)
    Proceedings of the Annual Meeting of the American Society of Biomechanics
  • Cytoskeleton reorganization of spreading cells on micro-patterned islands
    Item type: Journal Article
    Loosli, Y.; Luginbuehl, R.; Snedeker, Jess Gerrit (2010)
    Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
    Predictive numerical models of cellular response to biophysical cues have emerged as a useful quantitative tool for cell biology research. Cellular experimentsin silicocan augmentin vitroandin vivoinvestigations by filling gaps in what is possible to achieve through ‘wet work’. Biophysics-based numerical models can be used to verify the plausibility of mechanisms regulating tissue homeostasis derived from experiments. They can also be used to explore potential targets for therapeutic intervention. In this perspective article we introduce a single cell model developed towards the design of novel biomaterials to elicit a regenerative cellular response for the repair of diseased tissues. The model is governed by basic mechanisms of cell spreading (lamellipodial and filopodial extension, formation of cell–matrix adhesions, actin reinforcement) and is developed in the context of cellular interaction with functionalized substrates that present defined points of potential adhesion. To provide adequate context, we first review the biophysical underpinnings of the model as well as reviewing existing cell spreading models. We then present preliminary benchmarking of the model against published experiments of cell spreading on micro-patterned substrates. Initial results indicate that our mechanistic model may represent a potentially useful approach in a better understanding of cell interactions with the extracellular matrix.
  • Toward intraoperative functional imaging of the rotator cuff tendons
    Item type: Other Conference Item
    Würgler-Hauri, C.C.; Li, Y.; Schuppisser, M.C.; et al. (2010)
    Swiss Medical Weekly
Publications1 - 10 of 321