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Motion Sensors in Osteoarthritis: Prospects and Issues
Published in Daniel Tze Huei Lai, Rezaul Begg, Marimuthu Palaniswami, Healthcare Sensor Networks, 2016
The peak KAM is the knee loading parameter which has been related to OA disease progression; a higher peak KAM increases the risk for disease progression (Miyazaki et al. 2002). The peak KAM increases with OA severity (Sharma et al. 1998), varus malalignment (Specogna et al. 2007; Wada et al. 2001) and faster walking velocity (Mundermann et al. 2004), and it is also associated with pain (Thorp et al. 2007) and surgical outcomes following high tibial osteotomy surgery (Prodromos, Andriacchi, and Galante 1985). Whether or not the peak KAM is related to the initiation of OA disease is less certain; however, there is some evidence suggesting this (Amin et al. 2004). While the KAM is closely related to medial compartment loading, as a net external moment it is obviously not a direct measure of the compressive forces between the bone surfaces. Unfortunately, such forces can only be measured by an instrumented knee prosthesis; these have actually been implanted in a very small number of patients undergoing knee replacement for knee OA (D’Lima et al. 2008; Kutzner et al. 2010; Mundermann et al. 2008; Zhao, Banks, D’Lima, et al. 2007). The KAM is closely associated with such direct measures of compressive joint force (Zhao, Banks, Mitchell, et al. 2007). The compressive joint forces can also be estimated by complex musculoskeletal mathematical models; however, there are many disparate modelling approaches that are still evolving and have yet to be fully validated (Buchanan et al. 2004, 2005; Correa et al. 2010; Lin et al. 2010; Shelburne, Torry, and Pandy 2006; Winby et al. 2009).
Neuromusculoskeletal modelling and simulation of tissue load in the lower extremities
Published in Youlian Hong, Roger Bartlett, Routledge Handbook of Biomechanics and Human Movement Science, 2008
David G. Lloyd, Thor F. Besier, Christopher R. Winby, Thomas S. Buchanan
This research is assessing how muscle activation patterns affect loading of the medial and lateral condyles of the tibiofemoral joint during walking. Large knee adduction moments in gait predict fast progression of medial compartment knee osteoarthritis (Miyazaki et al., 2002) and rapid reoccurrence of varus deformity of the knee after high tibial osteotomy (Prodromos et al., 1985). It is believed that large articular loading in the medial compartment of the tibiofemoral joint, produced by the adduction moments, causes the rapid osteoarthritic changes (Prodromos et al., 1985). Using a simple knee model, articular loading in the medial relative to the lateral compartment also predicts the bone density distribution in the proximal tibia (Hurwitz et al., 1998). However, muscle contraction may change the loading of the medial and lateral condyles of the tibiofemoral joint (Schipplein and Andriacchi, 1991) and must be taken into account. Indeed, altered muscle activations patterns, which include high levels of co-contraction of the hamstrings and quadriceps, have been observed in people with knee osteoarthritis (Hortobagyi et al., 2005) and in those who have undergone arthroscopic partial meniscectomy (Sturnieks et al., 2003). High levels of co-contraction may increase articular loading and hasten tibiofemoral joint degeneration (Lloyd and Buchanan, 2001; Schipplein and Andriacchi, 1991).
Personalized Implants and Additive Manufacturing
Published in Amit Bandyopadhyay, Susmita Bose, Additive Manufacturing, 2019
The above workflow does not necessarily create a personalized product or patient-specific implant but can be adapted to create personalized implant utilizing additive manufacturing. To elaborate on the manufacturing route of a patient-specific implant and guide, let us consider the making of components needed for high tibial osteotomy (HTO) surgery. This is a corrective surgery normally used on patients to correct instability due to misalignment of the tibial plateau to the femoral condyles, without compromising or violating the cartilage or menisci of the knee. Patient-specific information is needed to determine the extent of malalignment—so CT or MRI data are required. Based on this information, a surgeon can plan on making a slot in the region inferior to the tibial plateau. This slotted region will receive the implant—thus pushing superior the tibial plateau to correct the misalignment. The design team in collaboration with the operating surgeon would then design the HTO guides that allow the surgeon to position, orient, and make the necessary cuts in the region of the tibia. At the same time, an implant wedge is designed such that the cortical wall of the wedge seamlessly mates with the cortical bone of the receiving bone tissue while correcting the malalignment. Based on the approved design of the wedge, a Ti6Al4V implant, nylon guide, and nylon trial are manufactured. As these components are patient specific, the CAD files could contain patient-specific code identifiers that indicate components are for a particular patient, thus avoiding mix-up with components for other patients. The implant is made per the workflow listing described above, and the guides and trials are made per the procedure described in the earlier section. During surgery, the guide is used to prepare the implant receiving bone bed. Finally, the implant is placed inside the wedgeshaped cavity following normal surgical protocol for HTO. As the guide and trials are patient specific, they are discarded following surgery.
Biomechanical effects of screw orientation and plate profile on tibial condylar valgus osteotomy - Finite-element analysis
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
Chih-Ting Cheng, Chu-An Luo, Yi-Chih Chen
High tibial osteotomy (HTO) corrects the extra-articular deformities and has become a well-established treatment for the patients with early stage of medial knee osteoarthritis (OA) (Spahn 2004; Ryohei et al. 2009; Amis 2013). However, severe medial OA will develop intra-articular deformities, thus the clinical outcomes may not as good as expected when treating with HTO (Teramoto 2015; Chiba et al. 2017). Tibial condylar valgus osteotomy (TCVO) is a type of opening wedge HTO that was developed in 1990 in Japan (Chiba 1992; Teramoto 2015; Chiba et al. 2017; Koseki et al. 2017). It corrects intra-articular deformities by a L-shaped opening wedge osteotomy at medial tibial condyle. The osteotomy combines a transverse cut from the proximal medial tibia and a vertical cut extends to the lateral intercondylar eminence (Figure 1). Both TCVO and HTO correct the lower limb alignment, but HTO is usually used for mild to moderate medial knee OA (Trieb et al. 2006; Bonasia et al. 2014), while TCVO is believed that it can treat severe medial OA and reduce lateral subluxation of the joint (Chiba et al. 2017; Koseki et al. 2017).