Reliability of surface EMG measurements of the quadriceps during maximal isometric contractions following water immersion

Background: The influence of water immersion on neuromuscular function is of importance to a number of disciplines; however, the reliability of surface electromyography (SEMG) following water immersion is not known. This study examined the reliability of SEMG amplitude during maximal voluntary isometric contractions (MVICs) of the vastus lateralis following water immersion.

Methods: Using a Biodex isokinetic dynamometer and in a randomized order, 12 healthy male subjects performed four MVICs at 60° knee flexion on both the dominant and nondominant kicking legs, and the SEMG was recorded. Each subject's dominant and nondominant kicking leg was then randomly assigned to have SEMG electrodes removed or covered during 15 min of water immersion (20°C–25°C). Following water immersion, subjects performed a further four MVICs.

Results: Intraclass correlation coefficient (ICC) and the relative standard error of measurement (%SEM) of SEMG amplitude showed moderate to high trial-to-trial reliability when electrodes were covered (0.93% and 2.79%) and removed (0.95% and 2.10%, respectively).

Conclusions: The results of the this study indicate that SEMG amplitude of the vastus lateralis may be accurately determined during maximal voluntary contractions following water immersion if electrodes are either removed or covered with water-resistive tape during the immersion.

3D printed biocompatible enclosures for an implantable DBS microdevice

A number of methods have been used to make electronic medical microdevices biocompatible. This paper presents a novel approach for design and fabrication of biocompatible silicone enclosures for implantable medical microdevices. The approach involves design and formation of a 3D model of the enclosure using a computer-aided design software tool, followed by 3D printing of the enclosures using a bioplotter. Three different implantable enclosure designs are presented. The fabrication of the three enclosures is given. An evaluation of the suitability of the enclosures for implantation of a deep brain stimulation microdevice is discussed through submersion and operation tests. The evaluation results are presented and discussed.

Fabrication of biocompatible enclosures for an electronic implant using 3D printing

A variety of different approaches have been employed to enableimplantation of electronic medical microdevices. A novel method of producing low-cost, rapidly fabricated implantable enclosures from biocompatible silicone is presented in this paper. This method utilises 3D computer-aided design software to design and model the enclosures prior to fabrication. The enclosures are then fabricated through additive manufacturing from biocompatible silicone using a 3D bioprinter. In this paper, four different implantable enclosure designs are presented. A prototyping stage with three different prototypes is described, these prototype enclosures are then evaluated through submersion and operation tests. A final design is developed in response to the obtained results, and then evaluated in a long term temperature controlled submersion test. The evaluation results are presented and discussed.Several areas of future works are identified and discussed.