Strength testing of low-cost 3D-printed transtibial prosthetic socket.

Measurement and production of traditional prosthetic sockets are time-consuming, labor-intensive, and highly dependent on the personnel involved. An alternative way to make prostheses is using computer-aided design (CAD) and computer-aided manufacturing (CAM). Fused Filament Fabrication (FFF) may be an alternative to make low-cost prosthetic sockets. This study investigates the tensile properties of potential printing materials suitable for FFF according to ISO527 (Standard Test Method for Tensile Properties of Plastics). To ensure that FFF-printed sockets are safe for patient usage, the structural integrity of the 3D-printed prosthesis will be investigated according to ISO10328 (International Standard Structural Testing of Lower Limb Prostheses). Tough PLA was the most suitable print material according to ISO 527 testing. The Tough PLA printed socket completed 2.27 million cycles and a static test target value of 4025 N. Future research remains necessary to continue testing new potential materials, improve print settings, and improve the socket design for the production of FFF-printed transtibial prosthetic sockets. FFF using Tough PLA can be used to create transtibial prostheses that almost comply with the International Standard for Structural Testing of Lower Limb Prostheses.

3D-printed prostheses in developing countries: A systematic review.

BACKGROUND: According to the World Health Organization, only 5%-15% of people in lower-income countries have access to prostheses. This is largely due to low availability of materials and high costs of prostheses. 3D-printing techniques have become easily accessible and can offer functional patient-specific components at relatively low costs, reducing or bypassing the current manufacturing and postprocessing steps. However, it is not yet clear how 3D-printing can provide a sustainable solution to the low availability of limb prostheses for patients with amputations in lower-income countries. OBJECTIVE: To evaluate 3D-printing for the production of limb prostheses in lower-income countries and lower-middle-income countries (LLMICs). STUDY DESIGN: Systematic Review. METHODS: Literature searches, completed in April 2020, were performed in PubMed, Embase, Web of Science, and Cochrane Library. The search results were independently screened and reviewed by four reviewers. Only studies that examined interventions using prostheses in LLMICs for patients with limb amputations were selected for data extraction and synthesis. The web was also searched using Google for projects that did not publish in a scientific journal. RESULTS: Eighteen studies were included. Results were reported regarding country of use, cost and weight, 3D-printing technology, satisfaction, and failure rate. CONCLUSION: Low material costs, aesthetic appearance, and the possibility of personalized fitting make 3D-printed prostheses a potential solution for patients with limb amputations in LLMICs. However, the lack of (homogeneous) data shows the need for more published (scientific) research to enable a broader availability of knowledge about 3D-printed prostheses for LLMICs.

Target vessel displacement during fenestrated and branched endovascular aortic repair and its implications for the role of traditional computed tomography angiography roadmaps.

BACKGROUND: This retrospective study quantifies target vessel displacement during fenestrated and branched endovascular aneurysm repair due to the introduction of stiff guidewires and stent graft delivery systems. The effect that intraoperative vessel displacement has on the usability of computed tomography angiography (CTA) roadmaps is also addressed. METHODS: Patients that underwent fenestrated or branched EVAR were included in this retrospective study. Two imaging datasets were collected from each patient: (I) preoperative CTA and (II) intraoperative contrast-enhanced cone beam computed tomography (ceCBCT) acquired after the insertion of the stiff guidewire and stent graft delivery system. After image registration, the 3D coordinates of the ostium of the celiac artery, superior mesenteric artery, right renal artery and left renal artery were recorded in both the CTA and the ceCBCT dataset by two observers. The three-dimensional displacement of the ostia of the target vessels was calculated by subtracting the coordinates of CTA and ceCBCT from one another. Additionally, the tortuosity index and the maximum angulation of the aorta were calculated. RESULTS: In total 20 patients and 77 target vessels were included in this study. The ostium of the celiac, superior mesenteric, right renal and left renal artery underwent non-uniform three-dimensional displacement with mean absolute displacement of 8.2, 7.7, 8.2 and 6.2 mm, respectively. The average displacement of all different target vessels together was 7.8 mm. A moderate correlation between vessel displacement and the maximum angulation of the aortoiliac segment was found (Spearman's ρ=0.45, P<0.05). CONCLUSIONS: The introduction of stiff endovascular devices during fenestrated or branched EVAR causes significant, non-uniform displacement of the ostium of the visceral and renal target vessels. Consequently, preoperative CTA roadmaps based on bone registration are suboptimal to guide target vessel catheterization during these procedures.

People with amputations in rural Sierra Leone: the impact of 3D-printed prostheses.

We report the case of a man with a transhumeral amputation in a rural area of Sierra Leone. The patient had fractured his humerus during a football match. Due to lack of transportation and medical centres nearby, the patient was seen by a traditional healer. Although the traditional healer expected the fractured bone to heal within 3 days, the open fracture became infected. This finally resulted in a transhumeral amputation. The patient began to have a lack of self-confidence and felt excluded from society. He could not afford a conventionally fabricated prosthesis. Fourteen years later, the patient received a lightweight three-dimensional-printed arm prosthesis developed at the Masanga Hospital. The patient was very satisfied because the prosthesis met his criteria of aesthetics and functionality. His story highlights the socioeconomic hardship of being a person with an amputation in Sierra Leone and the need for affordable technological solutions.

Pioneering low-cost 3D-printed transtibial prosthetics to serve a rural population in Sierra Leone - an observational cohort study.

BACKGROUND: There is a huge unmet global need for affordable prostheses. Amputations often happen in Sierra Leone due to serious infections, complex wounds, traffic accidents and delayed patient presentation to the hospital. However, purchasing a prosthesis is still beyond reach for most Sierra Leonean amputees. METHOD: We applied computer-aided design (CAD) and computer-aided manufacturing (CAM) to produce low-cost transtibial prosthetic sockets. In February and March 2020, eight participants received a 3D printed transtibial prosthesis in the village of Masanga in Tonkolili district, Sierra Leone. Research was performed using questionnaires to investigate the use, participants' satisfaction, and possible complications related to the prostheses. Questionnaires were conducted prior to production of the prosthesis and five to six weeks after fitting the prosthesis. A personal short-term goal was set by the participants. FINDINGS: Competitively priced and fully functional prostheses were produced locally. After six weeks, all participants were still wearing the prosthesis and six of the eight participants reached their personal rehabilitation goals. Using their prostheses, all participants were no longer in need of their crutches. INTERPRETATION: We have come a step closer to the production of low-cost prostheses for low-and middle-income countries (LMICs). The goal of our project is to perform long-term follow-up and to refine our concept of 3D printed prostheses for LMICs to provide practical solutions for a global health need unmet to date. FUNDING: € 15,000 was collected during a crowdfunding campaign in collaboration with the Dutch Albert Schweitzer Fund. Internship allowance for MvdS was obtained from the University of Twente. 3D-scanner, 3D-printer, and printing material were donated by Ultimaker BV and Shining 3D.

Improving Lives in Three Dimensions: The Feasibility of 3D Printing for Creating Personalized Medical Aids in a Rural Area of Sierra Leone.

The aim of this feasibility study was to investigate how a 3D printer could be put to its best use in a resource-limited healthcare setting. We have examined whether a 3D printer can contribute to making prostheses, braces, or splints for patients who underwent major limb amputation because of complex wounds, for example, due to burns and subsequent scarring, accidents, conflicts, or congenital abnormalities. During a 3-month period, we investigated the benefits of customized, 3D-printed arm prostheses, splints, and braces in Sierra Leone. Using a handheld 3D scanner and a 3D printer, patient-specific medical aids were designed, manufactured, and tested. Questionnaires regarding patient satisfaction and the functionality of the prostheses were used for a short-term follow-up. Four esthetic prostheses were designed: two prostheses of the hand, one of the forearm, and one of the entire arm. Follow-ups were conducted after 3 to 4 weeks to investigate the quality of the prostheses and to complete a patient questionnaire. Even though the prostheses primarily fulfill esthetic needs, they also exhibit some degree of functionality. In addition, four splints for hands and arms were made to prevent scar contractures after skin transplantation. Finally, a brace for a young boy with kyphoscoliosis was manufactured. The boy has accepted the brace and will be followed up in the months to come. Long-term follow-up is required to prove the sustainability of the 3D-printed brace and prosthetic arms. Further research into how to sustain and refine this project is underway.