Construction of 3D model of knee joint motion based on MRI image registration

There is a growing demand for information and computational technology for surgeons help with surgical planning as well as prosthetics design. The two-dimensional images are registered to the three-dimensional (3D) model for high efficiency. To reconstruct the 3D model of knee joint including bone structure and main soft tissue structure, the evaluation and analysis of sports injury and rehabilitation treatment are detailed in this study. Mimics 10.0 was used to reconstruct the bone structure, ligament, and meniscus according to the pulse diffusion-weighted imaging sequence (PDWI) and stir sequences of magnetic resonance imaging (MRI). Excluding congenital malformations and diseases of the skeletal muscle system, MRI scanning was performed on bilateral knee joints. Proton weighted sequence (PDWI sequence) and stir pulse sequence were selected for MRI. The models were imported into Geomagic Studio 11 software for refinement and modification, and 3D registration of bone structure and main soft tissue structure was performed to construct a digital model of knee joint bone structure and accessory cartilage and ligament structure. The 3D knee joint model including bone, meniscus, and collateral ligament was established. Reconstruction and image registration based on mimics and Geomagic Studio can build a 3D model of knee joint with satisfactory morphology, which can meet the requirements of teaching, motion simulation, and biomechanical analysis.

Case 10.23

24-year-old pregnant woman with recent uterine bleeding Axial oblique 3D FRFSE (Figure 10.23.1) and sagittal oblique 2D FSE (Figure 10.23.2) images show a complex mass along the margin of the cervix with a central cystic region containing a small soft tissue structure....

Combined ligament injuries around the knee

♦ Any knee with major disruption of two ligaments is likely to have been dislocated at the time of injury♦ Knee dislocations are associated with high risk of neurovascular injury. Angiography or vascular ultrasound is mandatory♦ In knee dislocations, following immediate reduction and stabilization usually with a brace, acute repair of the ruptured soft tissue structure within 2–3 weeks of injury is likely to provide superior results compared to later reconstruction♦ Management of most multiligament injuries is complex and requires surgical intervention therefore specialist centres are best to be involved early♦ In cases with associated malalignment, osteotomy can improve the results of ligament reconstruction.

Pedicle preservation in a Silurian rhynchonelliformean brachiopod from Herefordshire, England: soft-tissue or an artefact of interpretation?—A Reply

ABSTRACTWe consider the reinterpretation of Bethia by Bassett et al. (2008) to be flawed in several regards. Details of the pedicle rootlets and wrinkles strongly imply a soft-tissue structure rather than calcified sheath. The ornament is unusual, but equally so under either an orthide or a plectambonitoidean model. The reinterpretation of the ‘deltial plates’ as ‘chilidial plates’ is likely correct, but argues against a plectambonitoidean affinity by implying that the pedicle emerges between the valves. Other arguments presented in favour of a plectambonitoidean affinity are also discussed; we consider them unpersuasive. Finally, we contend that Bethia is sufficiently well characterised to deserve a taxonomic name.