ResultsPreliminary results show that the combination of the multiaxial FDM approach and the use of polypropylene lead to functional and safe braces.The approach solves the problems of the layer structure and allows full freedom of design.Other characteristics of the braces, such as the impairment of the body climate, can thus be improved by design. ConclusionAdding additive manufacturing as the final step to the digital health care process can ensure complete product reproducibility.This opens the door for long-term optimization of the braces and the whole process.Using FDM as additive manufacturing technology can ensure a cost-effective and sustainable product life cycle.

Pressure ulcers (decubiti) are one of the most frequent side effects in the palliative care setting. Terminally ill and dying people have multiple comorbidities resulting in a high risk to develop pressure ulcers. These skin lesions are caused by pressure, friction and shearing forces in combination with several risk factors (e.g. moisture, tissue condition). People of all ages with reduced activity can suffer from decubitus ulcers. In palliative care, the treatment of symptoms to ensure the highest possible quality of life is of primary importance. Ethical controversies and difficult decision-making often lead to uncertainties and burdens for caregivers, patients and relatives. In the DekuProSys project, a decubitus prophylaxis system for inpatient and outpatient palliative care of people of all ages is being developed. The system will assist caregivers in patient care in multiple ways. It will capture and report risk factors for decubitus, assist at decision making and documentation. Furthermore, it will provide care information and instruction if needed. Aiming for an innovative and useful solution, the project follows a user-centered and interdisciplinary approach.

BACKGROUND:Skin diseases can develop upon disadvantageous microclimate in relation to skin contact with textiles of supporting devices. Increased temperature, moisture, mechanical fracture, pressure, and inflammatory processes often occur mutually and enhance each other in their adverse effects. Therefore, the early prevention of skin irritations by improvement of microclimatic properties of skin in contact with supporting devices is important.MATERIALS AND METHODS:In this study, the microclimate under occlusion with polyester, cotton, chloroprene rubber, and silicone textiles, used for supporting devices, was analyzed by determining several characteristic physiologic skin parameters in vivo, including temperature, moisture, and transepidermal water loss (TEWL). This is achieved by comparing a miniaturized in vivo detection device with several established optical and sensory methods in vivo.RESULTS:A highly significant TEWL decrease was found after polyester, chloroprene rubber, and silicone application. The application of all materials showed highly significant decrease in skin surface temperature, with chloroprene rubber showing the lowest. Similarly, all materials showed highly significant increase in relative moisture, where the highest increase was found for chloroprene rubber and silicone and the lowest increase for cotton. The cutaneous carotenoid concentration of chloroprene rubber, silicone, and polyester decreased. A manipulation of the surface structure of the stratum corneum was recognized for all materials except for cotton by laser scanning microscopy.CONCLUSION:The skin parameters temperature, relative moisture, antioxidant status, and TEWL can effectively characterize the microclimatic environment during occlusion with medical supporting materials. These parameters could potentially be used to develop standardized testing procedures for material evaluation.

Zusammenfassung Zur Funktions- und Betriebsfestigkeitsprüfung moderner Beinprothesen für aktive amputierte Menschen wurde am Fachgebiet Medizintechnik der TU Berlin ein servohydraulischer Prüfstand entwickelt. Mithilfe einer robusten, adaptiven Regelungsstragie ist der Gangsimulator in der Lage, komplexe, hochdynamische Bewegungsabläufe mit Beinprothesen mit großer Genauigkeit durchzuführen.

A test device for lower limb exoprostheses has been developed at the Department of Medical Engineering of the TU Berlin which is able to apply realistic loads to prostheses. Hence, the gait simulator meets the increasing demands on functional and fatigue testing of microprocessor controlled knee joints (MPK). An exemplary comparison of two MPK was performed to prove that known differences in the functional quality of the MPK can also be demonstrated in simulator tests. Significant differences between the MPK could be found. The MPK could not be tested in their full range of function though. To enable comprehensive functional and fatigue testing, the gait simulator has to be modified to achieve higher walking velocities and step lengths.

To test the function and structural durability of modern lower limp prosthetics for active amputees, the Medical Technology Group of the TU Berlin has developed a servohydraulic test bench. By means of a robust, adaptive closed loop control strategy the gait simulator can perform complex and highly dynamic motion sequences with great precision.