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The Anatomy of Joints Related to Function
Published in Verna Wright, Eric L. Radin, Mechanics of Human Joints, 2020
The ligaments described by the gross anatomist may be considered to function in two ways. Some are under tension throughout most or all of the range of movement. When attached at or very close to the axis of movement, the fibers of a ligament remain taut and hold the joint surfaces together in close apposition. This is the situation of true collateral ligaments in a classic hinge type of joint, approximated most closely by the interphalangeal joints of the fingers (17,18). The cruciate ligaments of the knee also fall into this functional category. They provide the single most important union between femur and tibia, and additionally their attachments away from the axis of motion give them an important role in determining the complex pattern of movement that is flexion and extension of the knee (this is considered more fully later). Other ligaments that perform an equivalent function lie outside their joint capsule but still provide the major bond between bones: indeed they are the fulcrum about which movement occurs. The joints at both ends of the clavicle function in this way (Fig. 2), the costoclavicular ligaments determining sternoclavicular movement (19) and the coracoclavicular ligaments controlling movements at the acromioclavicular joint (20,21). Active opening of the mouth also depends on a similar mechanism (Fig. 3A). The stylomandibular ligament and sphenoman-dibular raphe, both attached well away from the temporomandibular joint, form a complex pivotal mechanism by which anterior displacement of the mandibular condyles by the lateral pterygoid muscles results in depression of the body of the mandible (22–24).
Preliminary simulation model toward the study of the effects caused by different mandibular advancement devices in OSAS treatment
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2018
Agnese Brunzini, Antonio Gracco, Alida Mazzoli, Marco Mandolini, Steve Manieri, Michele Germani
For the simulation, the following three contact models have been imposed:Fixed: ground to temporal boneFrictionless: articular disc to glenoid fossa, teeth to MADBonded: articular disc to condyle, temporomandibular ligament to temporal bone, temporomandibular ligament to mandible, sphenomandibular ligament to temporal bone, sphenomandibular ligament to mandible, stylomandibular ligament to temporal bone, stylomandibular ligament to mandible, periodontal ligaments to mandible, periodontal ligaments to teeth.
The Biomechanical Effects of Sagittal Split Ramus Osteotomy on Temporomandibular Joint
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2018
Zhan Liu, Jingheng Shu, Yuanli Zhang, Yubo Fan
According to the previous study (Liu et al. 2008, 2016), contact elements were used to simulate the interaction between the disc and the cartilages of the condyle and the temporal bone, with friction coefficient 0.001. Nonlinear cable elements were used to simulate the temporomandibular ligament, sphenomandibular ligament and stylomandibular ligament with corresponding stiffness values (Liu et al. 2008; Muralidhar et al. 2000). In addition, the discal attachments, including temporal anterior attachment, mandibular anterior attachment and bilaminar zones, were also modeled as nonlinear cable elements with referenced stiffness (Chen and Xu 1994; Liu et al. 2008). The model was named as PRE.