Injury
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The purpose of this study is to report the long-term follow-up result of allograft reconstruction of segmental defect of the humeral head associated with posterior dislocation of the shoulder. Six men underwent operative management of defects of the humeral head involving 40% of the articular surface, following posterior dislocation of the humeral head. The period of time between dislocation and surgery ranged from 7 to 8 weeks. ⋯ The other two patients developed collapse of the graft and osteoarthrosis that were yet evident at 4-year follow-up. These patients required a shoulder arthroplasty 8 years after the procedure. We conclude that the treatment of segmental defects of the humeral head associated with posterior dislocations of the shoulder by allograft reconstruction has a good long-term follow-up result in 50% of the patients.
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The universal availability of CT scanners has led to lower thresholds for imaging despite significant financial costs and radiation exposure. We hypothesised that this recent trend has increased the use of CT for upper limb periarticular fractures and led to more frequent operative management. ⋯ During the examined 5-year period no increases of in CT imaging frequency were observed. The significantly increased number of operations among older patients is unlikely to be driven by imaging frequency.
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Anatomicaly preformed variable-angle locking plates are technologically mature and appear to be optimal for the fixation of distal radius fractures. However, there is still much argument about whether volar plating is equivalent to dorsal (buttressing) plating, especially in the management of intra-articular extension fractures. This biomechanical study was performed to determine, in a simple intra-articular fracture model, whether dorsal or volar plate constructs would be more stable. ⋯ Biomechanically, volar plating with a modern variable-angle locking plate is equivalent to dorsal plating with two modern variable-angle locking plates.
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This study determines the relative effects of changes in osteoporosis condition, plate/screw design factors (plate angle/length/width/thickness and screw diameter) and fixation methods (screw number and screw length) on the biomechanical response of dorsal double plating (DDP) fixation at a distal radius fracture to determine the optimal design and evaluate its biomechanical strength using the dynamic fatigue test. Eighteen CAD and finite element (FE) models corresponding to a Taguchi L18 array were constructed to perform numerical simulations to simulate the mechanical responses of a DDP fixed in a simply distal radius fracture bone. The Taguchi method was employed to determine the significance of each design factor in controlling bone/plate/screw stress and distal fragment displacement under axial (100 N), bending (1 N m) and torsion (1 N m) loads. ⋯ The average stiffness in 20,000 test cycles was 425.7 N/mm, 461.1 N/mm and 532.1N/mm for the 0°, 30° and 60° constructs, respectively. No difference in stiffness was found in the same angled constructs throughout the 20,000 cycles of testing (p > 0.05). Lack of gross construct failures during cyclic testing and reasonable stiffness corroborated that our new constructs tested to date seem stable enough to support restricted post-operative loads.
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Considering the potential use of growth factors carried by liposomes for bone repair, this study aimed to assess the progress of bone healing process in injured alveoli of rats after administering EGF within liposomes. For this assessment we used 48 male Wistar rats that had their maxillary second molar extracted and separated into 5 groups: sockets filled with blood clot (BC), treated with empty liposome (L), PBS (P), EGF in PBS (EGF-P) and EGF in liposome (EGF-L). The animals were sacrificed after 3, 7, 14 and 21 days after surgery. ⋯ Nevertheless, groups BC, L, P and EGF-P followed a regular time for regeneration significantly different from the EGF-L group, which showed faster recovering. A higher expression of fibronectin and type III collagen in the group EGF-L after 3 and 7 days of surgery was observed and might be explained by the ability of the liposome to deliver EGF in a controlled manner, stimulating mesenchymal cells migration and osteoblast differentiation. As liposome efficiently regulated the availability of EGF without risks for its function and protected the factor from early absorption and degradation, the present work indicates that liposomes can be successful used as carriers for controlled delivery of growth factors in bone healing.