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Iedereen heeft de morele plicht zijn medemens in nood naar best vermogen bij te staan. In onze moderne samenleving staan een grote groep artsen, een brede waaier van paramedisch personeel en een hele reeks geavanceerde apparatuur ter beschikking om slachtoffers van ongevallen de beste medische zorgen toe te dienen. Tussen het tijdstip van het ongeval en de eigenlijke medische verzorging verloopt er echter nog heel wat tijd. Om te voorkomen dat de toestand van een ongevalsslachtoffer in deze tijdsspanne beduidend verslechtert, is eerste hulp bij ongevallen onmisbaar. Dit handboek wil voor de EHBO'er een leidraad zijn voor de hulpverlening bij frequent en minder frequent voorkomende ongevallen. De ongevalssituaties worden op een leesbare en bevattelijke wijze in een logische volgorde besproken, en met vele figuren geïllustreerd. Dit boek bevat de reanimatierichtlijnen van 2010. (Bron: covertekst)

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Background. Internal fixation of a scaphoid fracture is usually done with K-wires or headless compression screws (HCS). These fixation methods are difficult and technically demanding due to the complex shape of the scaphoid and lead to non-union in approximately 10% of cases. It is crucial to achieve bony healing to prevent scaphoid non-union, evolution to advanced collapse and ultimately osteoarthritis of the wrist, which leads to a significant functional impairment. Recently, plate osteosynthesis of the scaphoid bone was re-introduced as treatment modality. Patients and Methods. A systematic review of the existing literature was performed about scaphoid plating in scaphoid fractures and non-unions. Pubmed MEDLINE, Embase, Scopus and TRIP database were searched from the first records up to 31/08/2018, restricted to the English language. Twelve articles were selected by two independent reviewers, all of them are descriptive studies. A total of 125 cases are reported in 124 patients. Radiological healing was chosen as the primary outcome measure. Hardware complications is our secondary outcome parameter. Functional outcome, follow-up and patient characteristics are reported as well. Results. A total of 118 out of 125 fractures achieved bony healing by scaphoid plate osteosynthesis in a mean time of 4.1 months. Fourteen patients needed plate removal because of discomfort. A trend of improvement or stabilisation in pain relief and range of motion was observed. Conclusion. Scaphoid plate osteosynthesis leads to excellent radiological healing in scaphoid non-unions and fractures. These results correlate with recent biomechanical studies suggesting that plates lead to a form of fixation with better stability compared to HCS. A disadvantage is the relative high hardware complication rate that can require a second operation for removal.

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Osteoarthritis (OA) is one of the most common causes of disability in older people. Obviously it has a tremendous effect on the life quality of an individual, but it also has a large socio-economic impact. Due to the increasing life expectancy, these costs will only increase. To be able to reduce these costs, fundamental changes should be made in the way care is given to patients suffering from OA. New and better treatments can only be found if the disease is better understood. One wants to be able to quantify the changes between a healthy joint and one with degraded cartilage. This quantification of the stresses and strains in the cartilage layers of a joint can be achieved using FE- (finite element) modelling. This project focusses on modelling the wrist joint. In the past only a few FE-models of the entire wrist joint have been published. In these models, the cartilage has never been extracted from images. It is however easy to understand that the geometry of the cartilage has a large effect on the stresses and strains generated within those cartilage layers. In this project, the stress and strain distribution in the cartilage layers of the wrist joint are determined using an FE-model and are experimentally validated. The geometry of both the bones and cartilage layers is extracted from Computed Tomography (CT) images. Based on the imaged geometry, an FE-model (Analytical model) is built. An experimental validation of this model is done, using a device that can apply a load on a cadaver wrist. A CT-scan is made of the wrist in loaded and unloaded condition. Based on these scans, the displacements of the bones are calculated. An FE-model (Experimental models) is used to convert the computed displacements into stresses and strains in the cartilage layers. The stress and strain distribution in the cartilage layers computed by the Analytical and Experimental models are compared to validate the Analytical model. This project is a first study in which an FE-analysis of the entire wrist joint, based on cartilage layers extracted from images, is successfully performed. Methods to visualize the cartilage, build the model and validate the model are described.

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The carpometacarpal-1 (CMC-1) joint, the joint between the trapezium bone in the wrist and the thumb, is commonly affected by osteoarthritis, a disease characterized by the loss of cartilage. Multiple treatments can be offered to the patients depending on the stage of the disease. Though, there is still a lack of insights in the disease and its treatments. Therefore, in order to make a finite element model of the trapezium bone to get more insights, this research determined the boundary conditions through an experiment on a cadaver hand. The focus lied on measuring the contact pattern and pressures acting on the trapezium bone in the CMC-1 joint during lateral key pinching, as this is a common position causing pain in arthritic joints. To obtain a lateral key pinch, the specimen was mounted on a setup and the thumb muscles were mimicked by pulling on the tendons in their physiological direction with a specific force. When the tendons were tensioned, a sensor inserted in the CMC-1 joint and one placed underneath the tip of the thumb recorded the pressures. This recording was repeated for five different tendon loads and for two different amounts of loaded tendons. The contact pattern in another joint with the trapezium, the scaphotrapeziotrapezoidal (STT) joint, was also measured, though not for increasing tendon loads. From the outcomes, the CMC-1 contact pattern was observed to be located at the dorsal-radial aspect of the trapezium bone and to shift to an even more dorsal and radial side with increasing tendon loads, suggesting a change in bone seating. In addition, within the range of applied proportionality factors, the exerted thumb-tip force was observed to increase exponentially with increasing loads, suggesting a nonlinear behavior of the finger. Using more tendons to mimic the lateral key pinching resulted in a higher thumb-tip force, whereas the pressure range (0.1 - 1.2 MPa) and pressure distribution in the CMC-1 joint did not significantly change. In the STT joint, a dorsal-ulnar contact pattern was observed, and both the pressures and the contact area turned out the be smaller than in the CMC-1 joint, which might explain the lower prevalence of isolated STT osteoarthritis.

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Wrist osteoarthritis is one of the most common diseases affecting the wrist joint. In severe cases, a surgical procedure is the only option left to provide the patient with pain relief and restore the wrist function. Two frequently exerted wrist surgeries are proximal row carpectomy (PRC) and four-corner arthrodesis (FCA). A problem is that the long-term outcomes of these surgical procedures are not equally good for each patient and some patients need to undergo a revision surgery, which is better avoided. Therefore, predicting the outcome of a wrist surgery is of great interest. A possible way to predict this, is by looking at changes that occur in the microarchitecture, trabeculae, of the wrist bones. If different patterns arise in the changes of the bone microstructure between operated wrists with and without complications, this difference can be used for a prediction of the surgical outcome. Therefore, the aim of this thesis was to develop a workflow for the quantification of longitudinal changes in the bone microarchitecture of wrist bones after surgery. CBCT images with an improved spatial resolution were used to visualize the trabeculae of the bones. To account for the different position of the wrist inside the scanner between the two images, an optimal registration procedure was developed. Based on a parameter analysis and a validation, the optimal registration parameters were selected. A rigid registration of each bone at a time produced good results. For the comparison of the bone microstructure, a segmentation procedure was constructed based on a segmentation algorithm for ex vivo CBCT images. The segmentation performed well in general, but had difficulties with fine detailed trabeculae and in regions where the bones were closely positioned to each other. The registration and segmentation were combined into one workflow to produce an overlap image of the segmentation of the baseline and follow-up image. Regions of bone formation and resorption could be identified this way. As the segmentation had no validation and the follow-up image was more noisy than the baseline image, it was difficult to assess changes in the bone microstructure with certainty. Although different indications were available towards more bone resorption than formation. These were located in the neighbourhood of the newly formed contact surface between the radius and capitate after surgery. In conclusion, there is shown that CBCT images have the possibility to assess longitudinal changes in the bone microstructure of the wrist bones over time and that the developed workflow is a good method to do so. Improvements need to be made to different aspects of the technique such as the in vivo segmentation and quality of the CBCT images.