Biomechanical analysis of a novel Y-plate designed for the treatment of extraarticular distal humerus fractures

Adult distal humerus fractures are infrequent, yet they account for one-third of all humerus fractures. For the treatment of comminuted and osteoporotic fractures, locking plates are claimed to be biomechanically superior to alternative internal fixing techniques. Treatment remains difficult despite recent advancements and the use of locking plates due to frequent comminution, low bone quality, and limited healing ability in osteoporotic bone. An optimal design of the newly constructed plate and the control model were selected. The biomechanical characteristics of non-osteoporotic and osteoporotic synthetic bone were compared on six models. The biomechanical properties of the new plate were tested and compared on 54 osteoporotic synthetic humerus models. The control models were reconstructive and parallel LCPs. The tests were carried out under static and dynamic axial, lateral and bending loads. Fracture displacements were measured by optical measuring system Aramis. The test model is significantly stiffer for lateral load (p = 0.0007) and for bending load at the moment of model failure (p = 0.0002), while for axial load the LCP model showed greater stiffness (p = 0.0017). During lateral dynamic loading, all three LCP models broke and there was a significant difference compared to the test model (p = 0.0125). The LCP model is dynamically significantly more durable under axial load, while the largest displacements were recorded with the test model (p = 0.029). The displacements induced by all three loads are within the limits that fulfil the parameters of appropriate biomechanical stability. A novel locking plate for extra-articular distal humerus fractures may provide an alternative to the traditional two-plate.     

晕船适应和脱适应相关因素的调查与分析

目的调查相关因素对晕船适应及脱适应过程的影响。方法采取同一调查者上船一对一采访的方法，对有初期晕船史的船员共152人进行问卷调查。结果初期重度晕船者占64．5％，轻度占35．5％，累计适应时间在1周内占18．4％，2周内占43．4％，4周内占68．4％，8周内占78．9％，8周内仍不适应者称为不适应者（占21．1％），累计2周内脱适应者占18．3％，4周内占55．0％，8周内占63．3％，脱适应期在8周以上占36．7％。结论晕船的适应期大部分在4周内，脱适应期大部分在4周及4周以上，合理安排训练时间和周期将会起到更好的抗晕船训练效果。     

Immunoblotting of Creutzfeldt-Jakob disease prion proteins: host species-specific epitopes

Creutzfeldt-Jakob disease (CJD) is a rare dementia that is generally found in older people and is caused by unusual infectious pathogens or prions. Using rabbit antisera raised against hamster scrapie prion proteins (HaPrPSc), we identified by immunoblotting human CJD prion proteins (HuPrPCJD) in the brains of 14 patients dying of CJD. Extracts from 6 of the patients were transmitted to mice after prolonged incubation. The rabbit antisera raised against HaPrPSc also reacted with the mouse CJD prion proteins (MoPrPCJD) found in the brains of these experimentally infected mice. When mice were immunized with HuPrPCJD, they produced antibodies that reacted with HuPrPCJD but not with MoPrPCJD. Mice immunized with MoPrPCJD produced antibodies to neither murine nor human prion proteins. Our results provide evidence for host species-specific epitopes on prion proteins. The existence of such epitopes is consistent with the apparent lack of an immune response during prion infections and the finding that prion protein molecules are encoded by host genes.     

Effects of restriction of forefoot rocker functions by immobilisation of metatarsophalangeal joints on kinematics and kinetics during walking

ObjectiveThis study was conducted to investigate the effects of restriction of forefoot rocker (FFR) functions by immobilisation of unilateral metatarsophalangeal joints (MPJs) on kinematic and kinetic factors during walking.MethodsEighteen healthy young adults participated in this study. To immobilise the MPJs of the right leg, an aluminium sole plate (AS) was fixed on the sole of the foot. Kinematic and kinetic data were collected while each subject walked at a comfortable speed with the AS and without.ResultsIn the AS condition, the walking speed and contralateral step length were significantly decreased, and an asymmetrical centre of mass (COM) movement was observed. The range of plantarflexion motion and positive work by the ankle joint were decreased markedly during the late stance of the AS limb. In contrast, maximum hip and knee flexion angles in the swing phase of the AS limb and positive work by the bilateral hip joints over the gait cycle were increased.ConclusionsThe results suggested that MPJ immobilisation may result in marked motion limitation of ankle plantarflexion and inhibition of push-off by the ankle joint despite no restrictions on the ankle joint. These changes may interfere with gait speed and a smooth and symmetrical COM shift during walking.     

Ischemic toe after surgery for lesser toe deformities: An algorithm

Ischemia after correction of lesser toe deformities is usually due to temporary vasospasm and can rarely cause gangrene. The published literature on dealing with the issue and been reviewed and used to suggest an algorithm for a logical step by step approach to a pale or white toe when encountered in the postoperative period.     

Bioactive glass,a new tool for the treatment in the diabetic foot recalcitrant osteomyelitis: A case series with 24-month follow-up

BackgroundThe bioactive glass (BAG) is a promising solution for the reconstruction of bone defects and the eradication of infection in patients with osteomyelitis, however references to the treatment of diabetic foot osteomyelitis are scarce in the literature.MethodsOur experience in patients with diabetic foot osteomyelitis, who required surgical debridement and void filling, in which we use bioactive glass (n = 6), was evaluated. During a minimum follow-up of 24 months, the presence of persistent infection and healing rate, post-surgical complications, surgical reinterventions, degree of osseointegration and BAG-related side effects was analyzed.ResultsAt the end of the follow-up, none of the patients showed signs of persistent infection and the healing rate was 66.6% (4/6).Postoperative complications were noted in 3 patients and two of the them required new surgical intervention, both due to skin coverage or vascular complications.A complete osseointegration in the 66.6% of the patients and no cases of local adverse effects were recorded.ConclusionsThe bioactive glass can be a useful tool in the treatment of certain cases of diabetic foot osteomyelitis, provided that a multidisciplinary approach and strict patient selection is in place.Level of evidenceIV.