9 research outputs found
Fracture Repair: Its Pathomechanism and Disturbances
Healing of the bone fracture is a biological process that is based on various cell lineages recruited, activated and regulated by molecular mediators, namely chemokines, growth factors, and cytokines, cooperating in a cascade of events aimed to fill the fracture gap with callus. Remodeling of the callus rebuilds the microarchitecture to the mature bone—cancellous or compact, depending on the type of the bone that was primarily at the fracture gap. Restitution of the bone continuity requires activation of mesenchymal stem cells that transform into osteoblasts and mature into osteocytes. It is activated and regulated by molecules released from blood platelets from posttraumatic hematoma, traumatized tissues, nerve endings, and inflowing inflammatory cells. The significance of the inflammatory cells in this process is inappreciable, as they eradicate pathogens, remove wound debris, and supply the fracture gap with molecules regulating forthcoming cellular events. They also provide immune regulation of the healing. To proceed uneventfully, healing requires an adequate bone contact and biomechanical environment, proper oxygenation, and nutrition. Unfortunately, up to 15% of bone fractures show some kinds of disturbances that may result in cessation of reparative processes leading to non-union. Factors, responsible for that, are brought to date based on current literature and clinical observations
Nondestructive detection method for the calcium and nitrogen content of living plants based on Convolutional Neural Networks (CNN) using multispectral images
Herein, we present the novel method targeted for determination of plant nutritional state with the use of computer vision and Neural Networks. The method is based on multispectral imaging performed by an exclusively designed Agroscanner and a dedicated analytical system for further data analysis with Neural Networks. An Agroscanner is a low-cost mobile construction intended for multispectral measurements at macro-scale, operating at four wavelengths: 470, 550, 640 and 850 nm. Together with developed software and implementation of a Neural Network it was possible to design a unique approach to process acquired plant images and assess information about plant physiological state. The novelty of the developed technology is focused on the multispectral, macro-scale analysis of individual plant leaves, rather than entire fields. Such an approach makes the method highly sensitive and precise. The method presented herein determines the basic physiological deficiencies of crops with around 80% efficiency
Deformation of the Titanium Plate Stabilizing the Lateral Ankle Fracture Due to Its Overloading in Case of the Young, Obese Patient: Case Report Including the Biomechanical Analysis
The number of overweight and obese patients in developed countries is gradually increasing. It was reported that 1287 (64%) out of 2007 adults operated on in 2017 had a body mass index (BMI) greater than 25 kg/m2, and 26.4% even greater than 30, while the BMI of the most obese patient was as high as 57.6 kg/m2. Such distressing statistics raised an issue related to the inadequate durability of implants used for the fixation of bone fractures. Implants for the lower-extremity fractures may not be durable enough to fit the requirements of overweight and obese patients. This case report presents the history of a 23-year-old obese male with a BMI of 38.7, who bent the angularly stabile titanium plate stabilizing his broken lateral ankle and torn distal tibiofibular syndesmosis. Biomechanical analysis showed that the maximal static bending moment registered during one-leg standing was equal to 1.55 Nm. This value was circa one-third of the maximally admissible bending moment for this particular plate (5.34 Nm) that could be transmitted without its plastic deformation. Since dynamic forces exceed static ones several (3–12) times during typical activities, such as walking, climbing the stairs, running, and jumping, unpredictable forces may occur and increase the risk of loosening, bending, and even breaking implants. None of these situations should have occurred for the typical patient’s body mass of 75 kg, or even for the analyzed mass of the young patient (120 kg) who tried to avoid excessive loading during his daily routine. Subsequent implant bending and destabilization of the fracture shows that for the significantly high and still growing number of obese patients, a very strict physical regime should be recommended to prevent overabundant dynamic loads. On the other hand, the geometry of implants dedicated to these patients should be reconsidered
A Review on Biomaterials for Orthopaedic Surgery and Traumatology: From Past to Present
The principal features essential for the success of an orthopaedic implant are its shape, dimensional accuracy, and adequate mechanical properties. Unlike other manufactured products, chemical stability and toxicity are of increased importance due to the need for biocompatibility over an implants life which could span several years. Thus, the combination of mechanical and biological properties determines the clinical usefulness of biomaterials in orthopaedic and musculoskeletal trauma surgery. Materials commonly used for these applications include stainless steel, cobalt-chromium and titanium alloys, ceramics, polyethylene, and poly(methyl methacrylate) (PMMA) bone cement. This study reviews the properties of commonly used materials and the advantages and disadvantages of each, with special emphasis on the sensitivity, toxicity, irritancy, and possible mutagenic and teratogenic capabilities. In addition, the production and final finishing processes of implants are discussed. Finally, potential directions for future implant development are discussed, with an emphasis on developing advanced personalised implants, according to a patient’s stature and physical requirements
Fizjologiczne i histologiczne uwarunkowania technik regeneracji chrząstek stawowych oraz ich zastosowania kliniczne
In clinical setting no spectacular treatment results confirmed using histological approaches were noted as compared with these obtained in laboratory research (finding the regeneration built of the hyaline cartilage in the damaged area in the treated patients is very rare since, as a rule the regeneration is built of the fibrous cartilage). Numerous and increasingly frequent procedures aimed at regeneration of the articular cartilage using platelet rich plasma (PRP), isolated autogenous chondrocytes or mesenchymal precursor cells in patients with osteoarthritis provide access to the vast research material for the analysis of the efficacy and safety of the treatment, based on which, no definitely adverse consequences of the applied methods were noted, such as life-threatening consequences due to new tissue formation. However, the knowledge of the underlying mechanisms indicates the necessity of exercising caution in qualifying patients for such procedures and many years long monitoring in order to the fastest possible diagnosing and successful treatment of the complications.W warunkach klinicznych nie odnotowano spektakularnych, potwierdzanych metodami histologicznymi wyników leczenia jakie są uzyskiwane w badaniach laboratoryjnych (stwierdzenie u leczonych chorych wytworzenia w miejscu ubytku regeneratu zbudowanego z chrząstki szklistej jest rzadkością; regułą jest w zasadzie wytworzenie regeneratu chrząstki włóknistej). Olbrzymia i szybko rosnąca liczba wykonywanych zabiegów mających na celu regenerację chrząstek stawowych, w tym z użyciem osocza bogatopłytkowego, izolowanych autogennych chondrocytów czy mezenchymalnych komórek prekursorowych u chorych leczonych z powodu choroby zwyrodnieniowej stawów, udostępnia olbrzymi materiał badawczy dla analizy skuteczności i bezpieczeństwa terapii, na podstawie którego, jak dotąd, nie stwierdzono jednoznacznie negatywnych skutków stosowanych terapii w postaci groźnych dla życia powikłań wynikających choćby z nowotworzenia. Jednak znajomość mechanizmów ich działania zmusza do zachowania daleko idącej ostrożności w kwalifikowaniu chorych oraz ich stałego i wieloletniego monitorowania w celu jak najszybszego wykrycia i skutecznego wyleczenia powstałych powikłań
Destabilization of the comminuted clavicle shaft fracture due to breakage of the titanium locking plate: mechanical analysis
A Review on Biomaterials for Orthopaedic Surgery and Traumatology: From Past to Present
The principal features essential for the success of an orthopaedic implant are its shape, dimensional accuracy, and adequate mechanical properties. Unlike other manufactured products, chemical stability and toxicity are of increased importance due to the need for biocompatibility over an implants life which could span several years. Thus, the combination of mechanical and biological properties determines the clinical usefulness of biomaterials in orthopaedic and musculoskeletal trauma surgery. Materials commonly used for these applications include stainless steel, cobalt-chromium and titanium alloys, ceramics, polyethylene, and poly(methyl methacrylate) (PMMA) bone cement. This study reviews the properties of commonly used materials and the advantages and disadvantages of each, with special emphasis on the sensitivity, toxicity, irritancy, and possible mutagenic and teratogenic capabilities. In addition, the production and final finishing processes of implants are discussed. Finally, potential directions for future implant development are discussed, with an emphasis on developing advanced personalised implants, according to a patient’s stature and physical requirements