Mechanical Influences on Suture Development and Patency

Abstract

In addition to their role in skull growth, sutures are sites of flexibility between the more rigid bones. Depending on the suture, predominant loading during life may be either tensile or compressive. Loads are transmitted across sutures via collagenous fibers and a fluid-rich extracellular matrix and can be quasi-static (growth of neighboring tissues) or intermittent (mastication). The mechanical properties of sutures, while always viscoelastic, are therefore quite different for tensile versus compressive loading. The morphology of individual sutures reflects the nature of local loading, evidently by a process of developmental adaptation. In vivo or ex vivo, sutural cells respond to tensile or cyclic loading by expressing markers of proliferation and differentiation, whereas compressive loading appears to favor osteogenesis. Braincase and facial sutures exhibit similar mechanical behavior and reactions despite their different natural environments.

Brief communication: Ectocranial suture closure in Pongo: Pattern and phylogeny

“…These suture sites are also subject to environmental influences including adaptations to masticatory forces. These biomechanical forces are suggested to influence suture morphology (Moss and Young, 1960;Herring, 1972Herring, , 1974Herring, , 2000Herring, , 2007Herring, , 2008Herring and Teng, 2000;Byron et al, 2004Byron et al, , 2006Byron et al, , 2008 and similarities in these forces within and between species may contribute to the likeness in patterns of suture fusion in interspecific and intraspecific analyses.…”

The Global Impact of Sutures Assessed in a Finite Element Model of a Macaque Cranium

“…Should sutures be modeled using their complex, often interdigitating morphology, or as a simplified linear corridor? Surface investigation and micro-CT image analysis have demonstrated complicated spatial variations of sutural morphology (Byron et al, 2004;Byron, 2006Byron, , 2009Herring, 2008;Reinholt et al, 2009). Due to its pliant nature, the suture connective tissue is assumed to be able to resist mainly tensile rather than compressive loads.…”

“…Due to its pliant nature, the suture connective tissue is assumed to be able to resist mainly tensile rather than compressive loads. Therefore, bony interdigitations within sutures play a critical role in allowing external compressive loads to be absorbed as tensile forces through sutural fibers running between the inosculated sutural surfaces (Herring, 2008). Thus, sutures are better modeled as homogeneous suture-bone functional units in order to simplify this phenomenon (Farke, 2008;Wang et al, 2008b).…”

“…It is worth noting that there are significant variations among and within sutures in terms of morphological complexity and internal structural configurations (Byron et al, 2004;Byron, 2006Byron, , 2009Herring, 2008;Reinholt et al, 2009;Jasinoski et al, 2010). This variation may be due to variation in growth potentials (Massler and Schour, 1951;Ozaki et al, 1998;Opperman, 2000;Sun et al, 2004;Carmody et al, 2008;Wang et al, 2007a), dietary adaptations (Byron, 2009), genetic patterning (Wang et al, 2006a), aging processes (Gross, 1961;Milch, 1966;Miroue and Rosenberg, 1975;Kokich, 1976), fusion patterns (Wang et al, 2006c), and ontogenetic changes in material properties along with cortical bones (Wang et al, 2010a).…”

Assessment of the role of sutures in a lizard skull: a computer modelling study

“…In the vertebrate skull, individual bones are joined together at sutures by fibrocellular soft tissues (Herring 2008). The role of sutures in cranial biomechanics has interested vertebrate morphologists for decades (e.g.…”