Study, design and prototyping of arm splint with additive manufacturing process
The aim1 of this study is to propose the additive manufactured 3D printed technique for adaptive organic design splint as a solution for the problems generated by the use of casts in medical applications. Since the end of the XVIII century, when casts begin to be used, they have barely improved. Thanks to new manufacture and material techniques, we can improve and modernize this commonly used fracture treatment method. Based on three dimensional digitalization techniques and modeling via reverse engineering software, a 3D printed splint is proposed, which will provide the benefits of cast avoiding its deficiencies.
A history of splinting: to understand the present, view the past.
The purpose of this study was to identify, using an intensive literature review, the primary historical factors and events that shaped the evolution of current splinting technique and practice. Publication dates determine the chronological order of events, and splints are defined according to the ASHT Splint Classification System. Purposes of splinting are analyzed and listed according to frequency of citation in splint manuals and books, and a historical review of splinting practice describes splints, events, and persons who influenced the evolution of splinting from the time of Hippocrates through the 20th century. Factors influencing splint development include disease, political conflict, advancements in medicine and technology, agency and organizational decision making, centers of practice, and availability of information. Infection, polio, war, technology, plastics, surgical advances, soft tissue remodeling, anatomy, biomechanics, government agencies, hand centers, seminars, professional organizations, publications, and a classification system have all played important roles in 20th century splinting practice.
Repair of nerve gap with the elongation of Wallerian degenerated nerve by tissue expansion
We have found previously that expansion of the Wallerian degenerated nerve was accompanied by accelerated Schwann cell proliferation. In this study, we investigated the usefulness of the elongation of Wallerian degenerated nerve for the repair of short nerve gap. Male Wistar rats were used. After the left sciatic nerve was transected the rats were divided into 4 groups. In the control group, nerve coaptation was not performed. In group 1, tensionless coaptation was performed immediately. In group 2, delayed tensionless coaptation was performed with the elongation of Wallerian degenerated nerve. In group 3, coaptation was performed immediately with autologous interposition nerve graft. The ideal tensionless nerve repair of group 1 was considered to produce the best result. Rats in group 2 showed functional recovery as good as rats in group 1. On histologic assessment, in group 2, a fibrous capsule that was very rich in vascularity was formed around the tissue expander. After 14 weeks, the capsule was diminished markedly in size, but the vascularity was rich around the sciatic nerve. We think that the excellent functional recovery seen in group 2 can be attributed to the increased activity of Schwann cell proliferation and increased vascularity. © 1999 Wiley‐Liss, Inc. MICROSURGERY 20:126–130 2000