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Geometric Modeling of the Human Upper Extremity Based on Reconstructed Medical Images
Published in J. Middleton, M. L. Jones, G. N. Pande, Computer Methods in Biomechanics & Biomedical Engineering – 2, 2020
The radiocarpal joint was represented by two non-intersecting, perpendicular axes. These axes, which permit wrist flexion-extension and radio-ulnar deviation, respectively, pass through the proximal end of the capitate bone, but miss each other at the closest point by 5mm [11]. The flexion-extension axis was defined by fitting a variable-radius cylinder to triangles representing the cylindrically-shaped concavity at the distal end of the radius. The radio-ulnar deviation axis was defined to be perpendicular to both the flexion-extension axis and the axis of the third metacarpal (found by fitting a variable-radius cylinder to triangles isolated from the metacarpal shaft), and was located 5mm distal to the flexion-extension axis along the metacarpal shaft axis.
Joint-Articulating Surface Motion
Published in Joseph D. Bronzino, Donald R. Peterson, Biomedical Engineering Fundamentals, 2019
Kenton R. Kaufman and Kai-Nan An
Distal radioulnar joint space (mm) 1.6 ± 0.3 1.8 ± 0.6 0.06 Ulnar variance (mm) −0.2 ± 1.6 0.7 ± 1.8 0.003 Lunate, uncovered length (mm) 6.0 ± 1.9 7.6 ± 2.6 0.0008 Capitate length (mm) 21.5 ± 2.2 20.8 ± 2.3 0.0002 Carpal height (mm) 33.4 ± 3.4 31.7 ± 3.4 0.0001 Carpal ulnar distance (mm) 15.8 ± 4.0 15.8 ± 3.0 NS Carpal radial distance (mm) 19.4 ± 1.8 19.7 ± 1.8 NS ird metacarpal length (mm) 63.8 ± 5.8 62.6 ± 5.5 NS Carpal height ratio 52.4 ± 3.3 50.6 ± 4.1 0.02 Carpal ulnar ratio 24.9 ± 5.9 25.4 ± 5.3 NS Lunate uncovering index 36.7 ± 12.1 45.3 ± 14.2 0.002 Carpal radial ratio 30.6 ± 2.4 31.6 ± 2.3 NS Radius-third metacarpal angle (deg) −0.3 ± 9.2 −3.1 ± 12.8 NS Radius-capitate angle (deg) 0.4 ± 15.4 −3.8 ± 22.2 NS
Imaging of the upper limb
Published in Sarah McWilliams, Practical Radiological Anatomy, 2011
Fig. 8.5 (a) Lateral radiograph elbow: normally a fat pad (1) is seen anteriorly which should not be elevated. There should not normally be a posterior fat pad: AP view (b) of the wrist showing the radius articulating with the scaphoid and the lunate, but the ulna does not articulate with the carpus. The triangular fibre cartilage complex articulates with the ulna. Trapezium (2), trapezoid (3), capitate (4), hamate (5), scaphoid (6), lunate (7), triquetral (8), radius (9) andp ulna (10). (c) Lateral wrist showing the pronator quadratus fat pad (11). Third MCP (12). MCP = metacarpophalongeal joint.
Research on an intelligent evaluation method of bone age based on multi-region combination
Published in Systems Science & Control Engineering, 2023
Kaiyan Chen, Jianan Wu, Yan Mao, Wei Lu, Keji Mao, Wenxiu He
With the help of the position of key feature points, three target regions are extracted, and 10 key point positions are set for this purpose. The key feature points were as follows: the radial side of the distal ulna (near the radial side), the capitate centre, the first proximal phalanx centre, the first distal phalanx centre, the second middle phalanx, the third proximal phalanx centre, the third distal phalanx centre, the fourth middle phalanx, the fifth proximal phalanx centre, the fifth middle phalanx centre, and the fifth distal phalanx centre. The positions of the key points are marked in Figure 5, and the 10 feature points are represented by . The image annotation tool is labelimg. When extracting the region of interest, first read the position of the labelled feature points, and then extract according to the region of interest extraction algorithm. The region of interest extraction algorithm used in this article is the Region Proposal Network, which determines four data points based on the annotated anchor points: regional centre, reference direction, area width and area height to complete the extraction of the region of interest.
A fluid-structure interaction investigation of intra-articular pressure and ligament in wrist joint
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
Joachim Ee En Ong, Shi Lei Teng, Duncan Angus McGrouther, Hwa Liang Leo, Yoke Rung Wong
We postulate that this deviation can be caused by two reasons. From the perspective of computational simulation, only the dorsal ligament of the SLIL was included, omitting the proximal and palmar ligaments, as well as the neighbouring carpal joints. Exclusion of these connections causes the other half surface of synovial fluid to be ‘unbounded’. Therefore, we have to set ‘free surface of synovial fluid geometry’ that is unbounded and assigned with constant pressure of 1 bar. We acknowledge that such limitation of the study can affect the pressure change due to different surface pressure setting. In our future work, a more comprehensive dynamic CT scan of wrist motion will be carried out in order to obtain good quality of images for segmentation and 3D reconstruction of other neighbouring carpal bones such as trapezoid, capitate and hamate. From the perspective of experiment, the insertion of needle into cadaveric wrist could influence the flow pattern in the small scapholunate joint and caused higher than expected pressures.
Growth and maturity status of young male table tennis players
Published in Research in Sports Medicine, 2022
Manuel J. Coelho-e-Silva, Jan M. Konarski, Magdalena Krzykała, Szymon Galas, Pluta Beata, Piotr Żurek, Jorge Faria, Oscar M. Tavares, Tomas G. Oliveira, Inês Rodrigues, Diogo V. Martinho, João Valente-Dos-Santos, Robert M. Malina
Skeletal age (SA) estimated from the hand-wrist radiograph using the Fels method (Roche et al., 1988). The protocol considers specific indicators for the 22 bones of hand-wrist: the radius, ulna, capitate, hamate, triquetral, pisiform, lunate, scaphoid, trapezium, trapezoid, adductor sesamoid, metacarpals I, III and V, proximal phalanges I, III and V, medial phalanges III and V, and distal phalanges I, III and V. Maturity indicators for each bone include the presence or absence of the centre of ossification in the radiograph, changes in shape of the carpals, ratios of epiphyseal and diaphyseal widths of the long bones, and capping and fusion of the long bones. Assigned grades and width measurements were entered into the Felshw 1.0 software (Felshw 1.0, Software Lifespan Health and Research Centre, Departments of Community Health and Paediatrics, Booshoft School Medicine, Wright State University Dayton, Ohio, USA) to derive a SA and its standard error for each player. A single trained observer assessed all radiographs (first author). The maturity status of each individual was subsequently classified as follows (Malina, 2011): late (SA younger than CA by more than 1.0 year); average or on time (the difference between SA and CA was within the band of −1.0 years to +1.0 years); early (SA older than CA by more than 1.0 years); or mature (no SA is assigned).