In the field of individualized medical implants for bone replacesment, additive manufacturing offers far-reaching advantages for bridging bone defects and supporting the production of natural form and function. The article uses the example of a large, customized cranial implant to show the challenges of manufacturing with osteoinductive bone cements. The process is shown, starting with planning and design, through to functional integration using adapted manufacturing strategies to create defined porosity.

Introducing a Minimum Viable Product in the market and rapidly testing it proves valuable in assessing its value and potential. This involves experiments, gauging growth, and striving to diminish uncertainty in iterative cycles. The application of these approaches in healthcare, however, faces obstacles due to unique challenges including patient safety concerns and regulatory compliances. This paper undertakes a narrative literature review covering experiences of healthcare professionals and presents guiding considerations for medical startups to use in the market validation of their products.

Despite its significant advantages in terms of design freedom and the wide range of processable materials, the Binder Jetting technology has not yet received substantial attention in the healthcare field, especially concerning the fabrication of metal components. Hence, the paper investigates how this technology could be exploited to innovate the medical instrument field. Based on selected case studies, some preliminary design indications are derived on how to properly consider the various phases (i.e., printing, depowdering, and sintering) and related challenges of the Binder Jetting process.

Interest in applying a “lean” philosophy to design has been slowly growing in recent years, but there are still few broadly applicable methodologies and illustrative cases published in the literature to guide lean design processes. Lean approaches promise cost reduction and increased product value, which could be particularly beneficial in product development for low- and middle-income country markets, where value demands are high. We use the clinical need of efficient diabetic foot risk assessment in lowresource healthcare settings to present an example of lean early-stage design of a medical device. The background of existing medical literature and commercial products is intentionally leveraged throughout the design process to streamline development and minimize the need for independent validation of product strategies and design features. Our approach resulted in an efficient design process that generated a novel, purely mechanical plantar pressure evaluation device that can indicate high risk of diabetic foot ulcer in resource-constrained settings. This case provides a practical example of how design processes can be adapted to be leaner where there are large gains from minimizing design cycle time and cost.

Additive manufacture (AM) enables a greatly increased design freedom owing to its ability to manufacture otherwise difficult or impossible geometries. However, design creativity can often present itself as a barrier to realising the advantages that AM could offer. In this study the use of AM, bioresorbable materials and lattice design is considered as a method of satisfying contradicting design requirements during fracture healing. Often, immediately after a fracture high stiffness fixation is required; contradictingly during the remodelling phase high stiffness can inhibit bone healing. This study proposes the use of a bioresorbable body centred cubic (BCC) or face centred cubic (FCC) lattice structure to meet the need for tailored variation in implant stiffness over time. To reduce computational expense of lattice modelling a method is outlined, including the use of homogenisation. Results show homogenised representations perform within 5.2% and 1.4% for BCC and FCC unit cells respectively, with a 95% reduction in computational expense. Using resorption rates from the literature, time-dependent change in unit cell geometry was also modelled, showing the way in which a decrease in stiffness over time could be achieved.

Multidisciplinary design optimization (MDO) is a technique used in the design of systems involving the integration of many disciplines. The architecture and formulation of MDO has an impact on the solution time and optimality of final designs. The process of developing medical devices requires the combination of medical and technical knowledge and abilities. Developing a medical device is done by a complicated collection of Product Development Processes that entail tremendous oversight to ensure conformity to regulatory requirements. Regulatory standards often provide stern “Go / No-Go” policies which may discretize the design variables further increasing the complexity of the optimization problem. This work proposes a novel design approach which utilizes systems engineering practices to undertake complex multidisciplinary design optimization while implementing regulatory guidelines for medical devices. The formulated model is then applied and examined in a case study towards the development of a piezoelectric respiratory sensor. It is observed that the novel framework would extensively improve the design space definition and process driven product development practices.

3D printing is widely touted as a game changer in medicine and surgery, paving the way for point-of-care production of personalised medical devices. Nonetheless, to date, most reported applications of 3D printing in healthcare are restricted to specific scenarios in a few surgical disciplines, and little research exists on how 3D printing can be deployed more systematically beyond pioneer surgical departments. To understand the potential for 3D printing at a hospital level, we report the results of an interview study in a French general hospital. We analyse the current use of 3D printing and estimate the potential for new applications. We explore what share of these applications could be internalised, and what would be the organisational implications and the key success factors for an internal 3D printing unit. We find a large untapped potential for internal production of 3D printed products, spanning a much broader range of applications and hospital departments than what currently exists in the hospital. We then discuss important criteria to develop in-house 3D printing.

Atrial Fibrillation (AF) is one of the most prevalent cardiac diseases in the world. How might we design patient journeys improving quality of life using wearable cardiac devices for continuous out of hospital monitoring and support? Most of the studies to date have emphasised the technical aspects of implementing such devices with less focus on human factors. As such, remote cardiac monitoring appears to be burdened by poor patient adherence. This research study proposed a journey map based on Roger's technology adoption model to understand the challenges faced by AF patients and non/asymptomatic patients in using wearable devices to monitor their health. Data from semi-structured interviews conducted in Denmark with 12 participants aged 24 to 65 years was used. Interview results show that citizens prefer tracking heart activity only in conjunction with other measures such as steps or sleep and do not feel motivated to track their heart activity on a daily basis. Patients view wearables as a valuable tool to check if their health is all right, although apprehension that devices can cause unnecessary worry can lead to their rejection. Finally, recommendations for the design of patient journeys when using wearables were made.

Endotracheal intubation is performed to provide ventilatory support to a patient of any age. Every medical procedure that requires general anesthesia requires intubation, and for this reason, it is a life-saving procedure. This maneuver is a challenge in pediatric patients between 0 months and 12 years of age, since their anatomy and oxygen consumption differ compared to an adult.

In patients with difficult airways, where there is no good visibility of the structures, a videolaryngoscope is used. It has higher success rates compared to a conventional laryngoscope. Its use has become widespread since the COVID-19 pandemic, as it reduces exposure to respiratory secretions.

This article presents the design, manufacture and testing of a low-cost pediatric videolaryngoscope, for patients between 6 and 12 months, and which are intended to respond to the low availability of this type of equipment in Colombian health care centers. The BioDesign Innovation Process methodology was adapted for its creation. The prototypes were manufactured using 3D printing. Validation was performed by 28 experts using simulators and the results were promising, obtaining a success rate of 98.8% for the designed device.

Numerous and complex sequence of activities in medical device development often result in time consuming and expensive engineering processes. In this study, patient and designer requirements were identified and integrated within a novel framework which supports medical device design through a consolidated understanding of user-experience whilst directly coalescing the applicable regulatory requirements in terms of product compliance and certification. This assists in the development of safe and reliable products which reflect the need for increased usability considerations during design.

This work investigates the application of origami as the underlying principle to realize a novel 3D printed hand orthosis design. Due to the special property of some origami to become rigid when forming a closed surface, the orthosis can be printed flat to alleviate the most of the post-processing, and at the same time provide rigid support for the immobilized limb in the folded state. The contributions are the origami-based hand orthosis design and corresponding computational design method, as well as lessons learned regarding the application of origami for the hand orthosis design.

Open Abdomen (OA) therapy, is purposely leaving the fascial edges of the abdomen un-approximated after a laparotomy. During the OA therapy, there must be a temporary abdominal closure (TAC) device installed in the patient to achieve abdominal closure gradually without affecting its safety. However, the actual TAC devices have some gaps in terms of functionality or usability, therefore a new device is proposed. Intending to design a usable and functional technique for patients all over the world, the BioDesign Innovation Process was used. This iterative methodology focuses on healthcare needs, invention, and concept development with three main phases: Identify, Invent and Implement. At the end of these phases, the team successfully developed two new abdominal closure techniques that fill in the gaps of functionality and usability, using a simulator that realistically mimicked the physical and mechanical properties of an open abdomen. In terms of functionality, the novel techniques showed safe installation, operational security, secure grip, low invasiveness and control of intra-abdominal pressure. In terms of usability, the devices showed better results in efficiency, effectiveness and easy re-exploration than the control group.

Additive manufacturing enables new possibilities for the design of end products. These are rooted in the potentials of the manufacturing technology, such as flexible, tool-free production. These potentials can be used for the economic and flexible production of customized products. To support the use of the potentials, a development method was created which identifies optimization areas within a product. Therefore, the complexity is reduced by using of product functions. Characteristic functions and structural configurations are used to identify optimization areas. This contribution describes the application of the new development method to an existing mechanical transtibial prosthesis. In doing so optimization areas are identified which may make use of the potentials provided by additive manufacturing. One area is the interface between the prosthesis and the ground. By analyzing walking environments and the gait cycle the need for walking assistance on deformable surfaces was identified. Significant improvements were achieved through a functional integrated, additive manufactured foot sleeve.

A targeted development of safe medical products can be supported by design methods. This paper analyses which design methods are applied in the development of medical devices and whether they are adapted for considering medical devices’ special features (legal, human and technical issues). In particular, variety management, risk assessment and user-centered design for medical devices are examined. Typically, interdisciplinary risk assessment is methodically supported. Additionally, user-centered design methods for requirements assessment, design verification and design validation are applied.

Continuous subcutaneous insulin infusion using an insulin pump has been documented to have significant clinical benefits as a treatment plan for type 1 diabetes mellitus patients. However, despite this, adoption in resource constrained settings like India is severely limited. This is often attributed to the costs associated with the device.

The usage of such a device is closely associated with a patient's lifestyle and its design demands a more user-centric approach to engineering design. The stakeholder involvement is needed for validation and guiding the product development direction. In this paper, we've outlined a user-in-the-loop approach to engineering design using the design of an insulin pump as a case study.

This study defines a methodological procedure for the design and manufacturing of a prosthetic implant for the reconstruction of a midsagittal bony-deficiency of the skull due to the Apert congenital disorder. Conventional techniques for craniofacial defects reconstruction rely on the mirrored-image technique. When the cranial lesion extends over the midline or in case of bilateral defects, other approaches based on thin plate spline interpolation or constrained anatomical deformation are applied.

The proposed method uses the anthropometric theory of cranial landmarks identification for the retrieval of a template healthy skull, useful as a guide in the successive implant design. Then, anatomical deformation of the region of interest and free-form modelling allow to get the customized shape of the implant. A full bulk and a porous implant have been provided according to the surgeon advises.

The models have been 3D printed for a pre-surgical analysis and further treatment plan. They fulfilled the expectancies of the surgeon thus positive results are predictable.

This methodology results to be reproducible to any other craniofacial defect spanning over the entire skull.

High stiffness fracture fixation devices inducing absolute stability, activate inefficient primary healing and stress shielding. Taking High Tibial Osteotomy as a representative example, review of the clinical literature and mapping the fracture healing process revealed two physically contradicting requirements, which are only partially met by current techniques. Stiffness of the fixation is required immediately after fracture, however in the remodelling phase this can cause stress shielding. Stability is required immediately after fracture, however in the ossification phase less stability is required to stimulate secondary (and more efficient) healing. This study evaluates the use of the TRIZ Inventive Design Principles to overcome these physical contradictions. Six designs concepts were evaluated, of which the Macro-Geometry stiffness modulated design was ranked the highest. This was achieved through spatial decomposition of the problem utilising the Inventive Principles of Asymmetry, Extraction and Local Quality. This study offer perspectives on how to increase the patient specificity of fixation utilising the increased topology freedom of design for additive manufacture (AM).

A low cost robotic-assisted prototype for finger and hand rehabilitation of people affected by a stroke is presented. The system was developed by a team of undergraduate students led by a Design lecturer in collaboration with the Rehabilitation Unit of the Peñablanca Public Hospital in Chile.

The system consists of a flexion sensor equipped glove, a hand exoskeleton and an Arduino control unit. The patient wears the glove in his healthy hand. When s/he performs movements with the healthy hand, the sensors register the flexion of the fingers and send this information to the servo motors installed in an exoskeleton attached to the affected hand. In this way, the affected hand reproduces the movement of the healthy hand. The system uses a combination of the mirror therapy (the patient sees his/her affected hand moving in the same way that the healthy hand does) and passive exercising (as the exoskeleton produces the movement of the hand affected by the stroke). The combination of two types of therapy in a single low cost system makes the present work unique. In the near future, the developed prototype will be used to validate the effectiveness of the new proposed robotic therapy.

A neurointerventional training model called HANNES (Hamburg ANatomical NEurointerventional Simulator) has been developed to replace animal models in catheter-based aneurysm treatment training. A methodical approach to design for mass adaptation is applied so that patient-specific aneurysm models can be designed recurrently based on real patient data to be integrated into the training system.

HANNES’ modular product structure designed for mass adaptation consists of predefined and individualized modules that can be combined for various training scenarios. Additively manufactured, individualized aneurysm models enable high reproducibility of real patient anatomies. Due to the implementation of a standardized individualization process, order-related adaptation can be realized for each new patient anatomy with modest effort. The paper proves how the application of design for mass adaptation leads to a well-designed modular product structure of the neurointerventional training model HANNES, which supports quality treatment and provides an animal-free and patient-specific training environment.

This paper proposes a categorization of existing approaches to healthcare-related engineering design based on systems thinking principles. Three existing approaches to healthcare-related engineering design are isolated which contribute differently to health systems fundamental purposes and interconnections. The three approaches are labeled as 'silent', 'overt', and 'convergent' health design. Each approach is defined and illustrated through an example. Following, practical advantages and disadvantages of each approach are discussed. A reflection is offered on the expected relevance of the convergent health design approach for present and future societal challenges in the health domain, and specifically on the recently growing field of e-health. Finally, open methodological challenges related to convergent health design are outlined and characterized as opportunities for future research.