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Surgery of the Elbow
Published in Timothy W R Briggs, Jonathan Miles, William Aston, Heledd Havard, Daud TS Chou, Operative Orthopaedics, 2020
Alan Salih, David Butt, Deborah Higgs
For articular surface lesions a computed tomography (CT) arthrogram is desirable. It should be possible to readily convert from an arthroscopic procedure to an open procedure (see positioning and incision sections).
The Anatomy of Joints Related to Function
Published in Verna Wright, Eric L. Radin, Mechanics of Human Joints, 2020
It is instructive to consider a few examples of the relationship between articular surface geometry, the morphology of ligament attachments, and locomotor function to appreciate the beauty and precision of their coordination. The examples chosen are the knee, the ankle joint, the linkage of rotatory movements in the lower limb, and rotation at the atlantooccipital and atlantoaxial joints.
Treatment of distal intra-articular/extra-articular tibial fractures
Published in Peter V. Giannoudis, Thomas A. Einhorn, Surgical and Medical Treatment of Osteoporosis, 2020
Vasileios P. Giannoudis, Peter V. Giannoudis
Reconstruction of the articular surface should follow a logical sequence. Usually, reduction and fixation start from the posterior fragment before moving onto the more anterior parts of the joint. An external fixator placed between the tibia and the calcaneus or talus would allow better exposure and visualization of the fragments prior to reduction. Disimpaction of the fragments of the articular surface can be achieved with periosteal elevator and an osteotome. Using K-wires and pointed reduction forceps, anatomical reduction can be established, which can be verified by acquisition of the appropriate fluoroscopic views. Subsequently, 3.5 mm partially threaded cancellous screws can be used to provide compression to the anatomically reduced articular fragments. When the joint has been reconstructed, a bridge plating construct can be used to connect the articular block to the proximal tibial segment (Figures 28.6–28.8). Interfragmentary lag screws applied through the distal end of the plate can be used to provide additional stability to the articular fragments. Areas of previous impaction that have a residual bone void requiring filling for subchondral support can be addressed with the injection of bone cement (bone substitute). The stability of fixation can be checked by dorsiflexion and plantarflexion of the ankle joint. Additional low-profile small locking plates can be applied for capturing bone fragments that require additional buttressing for optimum fixation.
A novel knee joint model in FEBio with inhomogeneous fibril-reinforced biphasic cartilage simulating tissue mechanical responses during gait: data from the osteoarthritis initiative
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
Alexander Paz, Gustavo A. Orozco, Petri Tanska, José J. García, Rami K. Korhonen, Mika E. Mononen
Fibrils are grouped into 4 primary and 13 secondary fibrils. Primary fibrils represent the main collagen network architecture. They follow, in two pairs, the split lines depicted in Figure 1 and are depth-wise oriented. With respect to the articular surface, they are perpendicular at the deep zone, bent at the middle zone, and parallel at the superficial zone (Benninghoff 1925). Secondary fibrils, distributed spherically in 13 independent and random directions, represent the interconnectivity and randomness of the collagen network that contribute to the characteristic tension-compression behavior of the cartilage under different loading conditions (Kääb et al. 2003). The stress in a secondary fibril is
Secondary hip dysplasia increases risk for early coxarthritis after Legg-Calve-Perthes disease. A study of 255 hips
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
Andrej Moličnik, Jošt Janša, Boštjan Kocjančič, Veronika Kralj-Iglič, Drago Dolinar
We described the shape of the articular surface as a rotationally symmetric body, similar to an ellipsoid. However, as the region of the femoral head which bears most of the weight in the one-legged stance is located laterally and superiorly, we considered that the shape of the contour of the articular surface in the frontal plane is circular with the radius of the circle fitted to the curvature of the femoral head and the acetabulum in the range of the load bearing. In the hips with deformed femoral heads, there is considerable flattening of the head and acetabulum in that region, therefore, the radius of the articular surface circle in the frontal plane is large, and does not fit the contour of the femoral head medially and inferiorly. To obtain the shape of the articular surface which fits the joint optimally, the contour in the sagittal plane was taken to be quasi-elliptical. The appearance of the femoral head, however, is quasi-elliptical in the frontal plane and spherical in the sagittal plane. It should be born in mind that the articular surface is an abstract feature that is subject to the weight bearing and, therefore, outlines a particular region of the femoral head and the acetabulum. However, the deformation of the articular surface corresponds to the deformed appearance of the femoral head, considered by some authors who previously analysed development of hips after LCPD (Rowe et al. 2005; Shah et al. 2013).
Intra-articular drug delivery systems for osteoarthritis therapy: shifting from sustained release to enhancing penetration into cartilage
Published in Drug Delivery, 2022
Huirong Huang, Zijian Lou, Shimin Zheng, Jianing Wu, Qing Yao, Ruijie Chen, Longfa Kou, Daosen Chen
Articular cartilage is a thin layer of hyaline cartilage covering the articular surface at the end of the bone. It has a certain elasticity and smooth surface, which is enhanced for joint movement. Articular cartilage can be divided into chondrocytes and ECM. Chondrocytes play an important role in the stability of the knee joint. They secrete catabolic and anabolic enzymes to maintain the catabolism and anabolism balance of the cartilage tissue. The ECM is composed of matrix and collagen fibers. Type II collagen (Coll-II) accounts for about 90% of the collagen content in the extracellular matrix of cartilage, whereas proteoglycan is the main component of the matrix, containing at least one glycosaminoglycan (GAG) side chain.