Anatomical basis of the support of fibula to tibial plateau and its clinical significance

Background The fibula is only indirectly involved in the composition of the human knee joint and has therefore been neglected in the research on knee osteoarthritis. Nonuniform settlement of the proximal tibia plateau is clinically defined as when the height of the medial tibial plateau is lower than that of the lateral side in medial compartment knee osteoarthritis (KOA). The non-uniform settlement of the proximal tibia plateau may be caused by fibular support on the lateral side. Orthopedic surgeons practice partial fibulectomy based on the clinical manifestation of nonuniform settlement, and this technique has been shown to reduce pain and improve function in patients with medial compartment KOA. However, this hypothesis of the mechanism of nonuniform settlement lacks an anatomical basis. Methods The P45 polyester plastination technique was used to prepare sections of the proximal tibiofibular joint to investigate the distribution of the bone trabeculae in the region of the lateral tibial plateau. Results There was uneven distribution of trabeculae in the lateral condyle of the tibia and the head and neck of the fibula. The fibula and the posterolateral cortex of the shaft of the tibia united to form an arch beam via the tibiofibular joint. Many thick, dense trabeculae were present in a longitudinal direction above the tibiofibular arch. Conclusions The fibula supports the lateral tibial plateau, and the trabeculae were concentrated above the tibiofibular arch.

Anatomical Basis of the Support of Fibula to Tibial Plateau and Its Clinical Significance

BackgroundPartial fibulectomy always was used to treat knee osteoarthritis. The settlement of the nonuniform proximal tibia plateau is clinically defined as the height of the medial tibial platform was lower than that of the lateral side in the medial compartment knee osteoarthritis (KOA). The reason for the unapparent is caused by fibular support on the lateral side. Orthopedic surgeons practiced partial fibulectomy based on the theory of nonuniform settlement, and the effect of reduce pain and improve function in patients with osteoarthritis was significant. However, this hypothesis of nonuniform settlement is still lacking an anatomical basis.MethodsThe P45 section technique was used to focus the distribution of the bone trabeculae on the tibial-fibular region.ResultsThe distribution of the bone trabeculae was uneven in the lateral condyle of the tibia and the head and neck of the fibula. The bone trabeculae with uneven distribution of tibia and fibula in space might form a triangle. The fibula and the posterolateral bone cortex of the shaft of the tibia united to form an arch beam via the tibiofibular joint. In the meantime, a lot of thick and dense trabeculae were present in a longitudinal direction on the tibiofibular arch.ConclusionsThe fibula supports the lateral tibial plateau, but the trabeculae were concentrated on the tibiofibular arch.

Rocking Response of Free-Standing Rigid Blocks on Slopes

Structure, equipment, statue or storage cask may experience free-standing rocking on slopes because of the nonuniform settlement of the base, construction error or foundation failure. The free-standing rigid block on a slope subjected to one-sine pulse excitation and earthquake motions is examined in this paper. First, considering the free-standing rigid block on a slope, the overturning acceleration spectrum under one-sine pulse is built. The spectrum covers two overturning modes, i.e. overturning with one impact either before or after the excitation and overturning without impact. Then the influences of the slope on the overturning acceleration spectrum are discussed in depth. The analytical solution is compared with the numerical solution based on both linear and nonlinear formulations. It reveals that the safe region of the minimum overturning acceleration spectrum between mode 1 and mode 2 depends on the angle of the slope. Further, the block on a slope is subjected to the Tianjin, Kobe and Northbridge earthquake motions. By simplifying the main pulse of the motions to one-sine pulse, although the overturning acceleration spectrum fails to predict the overturning acceleration of the block subjected to real earthquake motions, it can provide some guidelines to predict the practical performance of the rocking structures.

Study on the Frame Structure under Nonuniform Settlement

In this paper, the effect of the non-uniformity settlement of ground foundation on the upper frame structure is studied. It takes a four-story space frame structure with two spans as an example. The different pedestals are installed at the joint of column footing, which respectively form the fixed supported model and the elastic supported model. Basin shaped settlement is applied in each model. The result shows that the beams are principally suffered with the bending moment and the columns principally suffered with axial force, shear force and bending moment, and that the elastic support model has certain economy.