Prediction Of Prosthetic Socket Fit Of Trans-Tibial Amputee With The Aid Of Computational Modeling

This study aims to investigate the pain-pressure relationship of the residual limb and the interface pressure at the prosthetic socket-residual limb interface during walking. Load was indented to different regions of the residual limb through Pelite and polypropylene indenters connected to a force transducer until pain was just perceived. A finite element (FE) model was built simulating the indentation process to evaluate the pressure distribution beneath the indenter upon indentation. Results suggested that pain is triggered when the applied peak pressure overshot a certain threshold. A second FE model was built to predict the socket-limb interface pressure, considering friction/slip and pre-stress produced by donning the limb into a shape-modified socket which were commonly ignored in previous models under simplifying assumptions. The predicted interface pressure was in the range of previous clinical pressure measurement and was below the thresholds causing pain. In future investigations, more subjects will be involved for the pain-pressure relationship and more analysis on interface pressure under different conditions, such as alignment, walking speed and style, will be performed

Avoidance of damage accumulation to minimize the risk of deep tissue injury: An investigative protocol of double loading episodes

Pressure ulcer is local tissue damage due to prolonged excessive loading acting on the skin. Evidence show that injuries can happen in the deep muscles before clinical signs on the skin. However, such deep tissue injuries if unattended could in time become massive lesions all the way to the skin. It is known that immediate muscle damage can occur as a direct mechanical insult under high enough loading. It is also known that damage can further build-up upon unloading due to subsequent reperfusion oxidative stresses and inflammation responses. Those loading-unloading tissues responses, if not appropriately relieved, can render the involved tissues more vulnerable to subsequent loadings, leading to a process of damage accumulation. In this presentation, we introduce an experimental protocol of double loading episodes to study the vulnerability of the involved tissues to such damage accumulation. A second loading episode is adopted in order to highlight the adequacy, or the inadequacy, of the preceding relief after the 1st loading episode and the vulnerability of those myofibers to further injury as a result of the 2nd loading episode. Given the load-duration of each episode and by varying the time between the two loading episodes, one may study using this approach how long it would take before the involved tissues can tolerate a 2nd loading episode - an issue that is clinically relevant to the design of pressure relief strategies for long-term bed-confined patients and for wheelchair-bound subjects with spinal cord injury. © 2011 Springer-Verlag Berlin Heidelberg.Link_to_subscribed_fulltex

A model for facilitating translational research and development in China: Call for establishing a Hong Kong Branch of the Chinese National Engineering Research Centre for Biomaterials

With significant improvements in living standards in China and the aging population that accompanies these improvements, the market demand for high-quality orthopaedic biomaterials for clinical applications is tremendous and growing rapidly. There are major efforts to promote cooperation between different scientific institutes with complementary strengths for the further development of the biomaterial industry in China to achieve the technological level of developed countries. An excellent example is that the Ministry of Science and Technology of the People's Republic of China (MOST; Beijing, China) established the Chinese National Engineering Research Centres (CNERCs), which serve as a major initiative in driving basic and applied technological research and development (R&D) in mainland China. To create a win-win situation with Hong Kong, the MOST and the Hong Kong Innovation and Technology Commission are jointly establishing the Hong Kong Branch of the CNERCs. Through an amicable arrangement, the Chinese University of Hong Kong (CUHK; Shatin, Hong Kong) and the Chinese National Engineering Research Centre for Biomaterials (i.e., Main Centre) in Chengdu, People's Republic of China have decided to apply to establish the Hong Kong Branch of the CNERC for Biomaterials at the CUHK. The effort in establishing the Hong Kong Branch of Biomaterials seeks to promote further collaboration with the Main Centre with the goals of promoting synergy and a win-win cooperation between mainland China and Hong Kong in scientific research, talent cultivation, clinically driven novel biomaterials product design, and preclinical and clinical testing. It will thus become a model for the successful collaboration between the Hong Kong research institutions and the mainland CNERCs in the area of biomaterials. Such initiatives will facilitate close collaboration in translational medicine associated with biomaterial development and application