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Modelling and simulation of tissue load in the upper extremities
Published in Youlian Hong, Roger Bartlett, Routledge Handbook of Biomechanics and Human Movement Science, 2008
Though the importance of shoulder biomechanics for effective orthopedics has long been recognized (Fu et al., 1991), researchers have recently focused on refining or developing surgical techniques with biomechanics. An investigation of massive rotator cuff repair techniques showed tendon transfer using teres major to be more effective than using latissimus dorsi (Magermans et al., 2004). Quantitative geometric shoulder models exist for the surgical planning of shoulder arthroplasty, reducing the likelihood of post-surgical implant impingement (Krekel et al., 2006). Studies of rotator cuff pathologies have focused on simulation of muscle deficiency to predict post-injury activation patterns and capacity (Steenbrink, 2006a; 2006b), with moderate success. Similar approaches have evaluated specific muscle transfers in the elbow by adjusting model-defined muscle attachment parameters (Murray et al., 2006). Despite the novelty of biomechanically assisted surgery, rapid advances make this a promising field.
Muscular Coordination in Working Postures
Published in Nigel Corlett, John Wilson, llija Manenica, The Ergonomics Of Working Postures, 1986
The curvcs in Figure 3 arc computed synergism patterns according to the computed coordination modes given in Table 1. Values for br Fim„, A, and j,, which arc required for these computations, were obtained from the literature. Comparison of the measured synergism with the computed synergism shows that during posture and slower movements, the curve which corresponds to mode 7 fits the data best. This suggests that for these muscular activities, in cats, a coordi-nanon mode similar to the minimum-fatigue mode is adopted. It is interesting to note that, according to the previous results, the minimum-fatigue mode is more efficient than other coordination modes. Because of the good fit between the experimental data and the forcc predictions of the minimum-fangue model, this model may be useful for forcc predictions during human posture and movement. For example, we have employed the minimum-fatigue approach to predict individual ankle muscic forccs in humans during standing and walking and, in particular, the mechanical effects of muscle tendon transfer surgery (Dul et al. 1985 b).
Techniques and Applications for Strain Measurements of Skeletal Muscle
Published in Cornelius Leondes, Musculoskeletal Models and Techniques, 2001
Microscopy affords direct observation of the tissue and has been useful in determining complex microstructural interactions.20,33 However, the size and proximity of the optics often preclude sarcomere measurements during mechanical testing except for single muscle fiber preparations. In an effort to automate sarcomere length measurements, De Clerk et al. captured microscopic images of muscle cell striations by video.20 Sarcomere lengths over a population of cardiac cells were determined by using a Fourier transform in which the spatial frequency of the spatially periodic sarcomeres was determined. The laser diffraction technique also makes use of the periodic structures of the sarcomeres in the muscle fiber. Acting as a diffraction grating, a monochromatic light passing through the fibers produces a diffraction pattern in which the distance between the first set of parallel lines is proportional to the sarcomete length.61,62 The laser affords the advantage of being able to measure average sarcomere lengths through a thicker sample than compared to microscopy. As a result, dissection times are substantially reduced using laser techniques. Laser techniques have the additional advantage of adaptability for use in measuring in situ sarcomere length. Fleeter et al. used laser techniques to measure sarcomere length of human forearm muscles in situ for use in tendon transfer surgeries to determine optimal muscle length before attachment of the tendon.28 Trestic and Lieber were also able to make in situ sarcomere length measurements. Using the frog gastrocnemius muscle, in which the central tendon typically precludes whole muscle diffraction measurements, these authors showed that diffraction measurements on partially dissected bundles containing approximately 100 fibers compared favorably with those of the intact muscle.106 Lieber et al. were also able to automate the laser diffraction method to measure sarcomere length in single muscle fiber tests. They report a frequency response of 3.8 kHz and a measurement accuracy of 0.043 μm.61 Thus, in single fiber measurement, laser diffraction techniques provide higher frequency response but somewhat lower spatial resolution than microscopy techniques.
Early functional treatment or trivialization? – current treatment strategies in lateral ligament injuries of the ankle
Published in European Journal of Sport Science, 2021
Daniel Popp, Johannes Weber, Maximilian Kerschbaum, Andreas Schicho, Florian Baumann, Franz Hilber, Werner Krutsch, Volker Alt, Christian Pfeifer
Nowadays, primary acute ligament ruptures of the ankle joint without involvement of the syndesmosis are treated non-operatively. Rehabilitation strategies include – similarly to rehabilitation after operative treatment – physical therapy as well as physiotherapy and training therapy (Thomas, Whalley, & Modi, 2009). Recurrent injuries and chronic ankle instability require surgical treatment. Surgical procedures as initially described by Brostrom et al. (Brostrom, 1966), are nowadays performed in modified techniques (Bajuri, Daun, Abdul Raof, Hassan, & Das, 2019; Rigby & Cottom, 2019) and show good to excellent results. However, if tissue quality is inferior and reconstruction using local tissue is not achievable, tendon transfer procedures are recommended (Hintermann & Renggli, 1999; Richter, Volz, Immendorfer, & Schulz, 2012; Sugimoto, Takakura, Kumai, Iwai, & Tanaka, 2002). Different techniques of those surgical treatment options with successful results have been published previously (Coetzee, Ellington, Ronan, & Stone, 2018; Pereira et al., 2018).
Towards patient-specific medializing calcaneal osteotomy for adult flatfoot: a finite element study
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2018
Zhongkui Wang, Masamitsu Kido, Kan Imai, Kazuya Ikoma, Shinichi Hirai
Regarding the MCO parameters, Spratley et al. (2014) investigated the differences in the plantar force distribution with 5 mm and 10 mm MCO translations using a rigid-body model. They reported a force decrease (−3.7 and −5.1% for a 5 and 10 mm translation, respectively) in the medial forefoot, force increase (+5.2 and + 9.0%, respectively) in the lateral forefoot, and force decrease (−1.8 and −2.8%, respectively) in the hindfoot. Similarly, in our study (Figure 8), we found a stress decrease (−5.19 and −12.17% for a 6 and 10 mm translation, respectively) in the medial forefoot (region 3) and stress increase (+5.56 and + 13.82%, respectively) in the lateral forefoot (region 5). In the hindfoot (region 8), we found a slight stress increase (+0.23%) with a 5 mm translation and stress decrease (−1.29%) with a 10 mm translation. The stress transition trends from both studies were similar, and the discrepancies were caused by the different flatfoot deformities and surgical procedures. In our study, only MCO was performed, but in Spratley et al. (2014), tendon transfer was performed prior to MCO.
Development of a more biofidelic musculoskeletal model with humeral head translation and glenohumeral ligaments
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Sujata Khandare, Meghan E. Vidt
Computational models provide a framework for integrating anatomical and physiological data that can help with understanding various aspects of shoulder stability, using tests that are not feasible to conduct in vivo. Previous studies have reported development of numerical models of the shoulder (Terrier et al. 2008), simulation frameworks for humeral head translations (Sarshari et al. 2017), finite element models of the glenohumeral joint (Favre et al. 2012), and multibody biomechanical models of the shoulder girdle (Quental et al. 2012; Quental et al. 2016). Models that define the geometry and force-generating properties of individual muscles enable understanding of intermuscular coordination and contributions of specific muscles to movement. Computational musculoskeletal models have been previously used to better understand shoulder biomechanics (Charlton and Johnson 2006; Nikooyan et al. 2011; Sins et al. 2015; Pataky et al. 2021; Khandare et al. 2022); compare shoulder loading under different tasks or working positions (Holzbaur et al. 2005; Dickerson et al. 2007; Pataky et al. 2021); assess pathological states, like tendon transfer (Holzbaur et al. 2005; Charlton and Johnson 2006; Nikooyan et al. 2011); and compare differences in subject-specific shoulder loading (Damsgaard et al. 2006; Vidt et al. 2018). However, existing upper limb models have represented the GH joint as a ball-and-socket joint due to the paucity of generalized HHT descriptions for model inclusion. Evaluation of HHT has become the target of research during the past few years and HHT values have become more available (Chopp-Hurley et al. 2016; Kozono et al. 2017, 2018; Staker et al. 2017). Moreover, the existing models include stiffness constraints at end ranges of rotational motion to represent aggregate force contributions from ligaments, rather than individual ligament contributions. This limits our understanding of how pathologic changes to ligaments can lead to non-physiological translation of the humeral head relative to the glenoid fossa. Therefore, there is a need to include HHT and individual ligament representations in the model. This will enable better understanding of HHT and ligament contributions on joint loading during movement, like activities of daily living, and in various conditions, like shoulder impingement, rotator cuff tear, or shoulder instability.