Introduction: Bone fractures represent a global health problem with the incidence of fractures on the rise each year. The predominant method for addressing bone fractures involves immobilization. Worldwide, many initiatives have sought to develop innovative fracture immobilization designs, and numerous solutions have been patented. However, a comprehensive overview and systematic classification of these patented designs is lacking. Areas covered: In pursuit of these patented immobilization designs, the Espacenet database, recognized as the largest global repository of patents, served as the principal investigative tool. Using a search string, patent classifications and inclusion criteria a total of 71 patents were identified. These can be classified into four unique design groups: (1) fixed and partly enclosed, (2) fixed and fully enclosed, (3) adjustable and partly enclosed and (4) adjustable and fully enclosed designs. The designs that are commercially available are predominantly situated within groups 3 and 4. Expert opinion: Advances in 3D scanning and additive manufacturing could improve comfort, personalization, and monitoring in fracture immobilization, but clinical adoption is hindered by slow production times, workflow misalignment, and regulatory barriers. Key improvements are needed in scanning accuracy, adjustment protocols, and integration into hospital logistics to ensure both technical feasibility and clinical usability.

By applying Axiomatic Design, a Smart Medical Cast was developed to provide patients, who are suffering from forearm fractures, with a personalized healing process. The device monitors the overall healing status and three complications, which are: Muscle Atrophy, Compartment Syndrome, and Deep Vein Thrombosis. In the conceptual phase, desk research has been performed to find biomarkers that correlate with the monitored processes. Per biomarker, a measuring principle has been designed and these combined formed the design of the smart medical cast. Following the design phase, two tests were performed on healthy individuals to measure the robustness in a real application. The first test focused on correctly measuring the biomarkers and further specifying the sensor specifications. For the second test, a new prototype was used to determine correlations between the measured data and the monitored process and the impact of application during the casting process. The test results show that the measuring system can measure the biomarkers within the expected range, except for bone density. No significant impact on the casting process was measured. The Smart Medical Cast has only been evaluated in situations without a fracture, the next step will be to test the measurables in an environment with a fracture.