Implant (medicine) | EPFL Graph Search

An implant is a medical device manufactured to replace a missing biological structure, support a damaged biological structure, or enhance an existing biological structure. For example, an implant may be a rod, used to strengthen weak bones. Medical implants are human-made devices, in contrast to a transplant, which is a transplanted biomedical tissue. The surface of implants that contact the body might be made of a biomedical material such as titanium, silicone, or apatite depending on what is the most functional. In some cases implants contain electronics, e.g. artificial pacemaker and cochlear implants. Some implants are bioactive, such as subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents. Applications Implants can roughly be categorized into groups by application: Sensory and neurological Sensory and neurological implants are used for disorders affecting the major senses and the brain, as well as other neurological di

Predrilled locking compression plate is more accurate than tension band wiring in restoring articular geometry of the ulnar greater sigmoid notch after olecranon Chevron osteotomy

Alexandre Terrier, Frédéric Vauclair

Introduction: The olecranon Chevron osteotomy (OCO) is commonly used to approach complex intraarticular fractures of the distal humerus. Predrilled tension band wiring (TBW) has historically been used to fix OCO. However, clinical outcomes are burdened by secondary loss of reduction and up to 21.3% non-union rates. The biomechanical stability of anatomic locking compression plate (LCP) was reported to be superior to TBW in olecranon fracture fixation. We hypothesised that this implant may also be superior to TBW in the anatomic reconstruction of the articular surfaces of the ulnar greater sigmoid notch after OCO by predrilling the holes of the angular stable plate with the threaded drill guide prior to osteotomy. Materials and methods: Lateral standardised and calibrated radiographs of twenty synthetic ulnar bones were obtained using a custom-made holder prior to preparation by a senior orthopaedic trauma surgeon. Ten specimens were then predrilled using the threaded drill bit guide of an olecranon LCP, while the other ten samples were predrilled with two 1.6 mm Kirschner wires. A distal "V" OCO was performed using a 0.6 mm oscillating saw. After repositioning and fixation with the corresponding device, lateral radiographs were repeated. Two independent observers used the TraumaCad planning software to document the articular geometry of the ulnar greater sigmoid notch pre- and postoperatively. The diameter of the best-fitting circle (diameter), the distance between the tip of the coronoid and the olecranon processes (distance) and the maximum articular depth were measured. Results: With the TBW technique, after OCO and fixation, all three postoperative measurements were significantly (p = 0.13). Inter and intra-observer measurement reliability was strong to very strong (intraclass correlation coefficients >= 0.793) for all three variables. Conclusion: Our study reveals that the predrilled LCP technique is more accurate than the predrilled TBW in restoring the anatomic articular geometry of the ulnar greater sigmoid notch after OCO. (C) 2020 Elsevier Ltd. All rights reserved.

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Fabrication and Packaging of a Fully Implantable Biosensor Array

Camilla Baj-Rossi, Sandro Carrara, Daniele Casarino, Giovanni De Micheli, Catherine Dehollain, Seyedeh Sara Ghoreishizadeh, Enver Gürhan Kilinç

In this work, we showed the realization of a fully- implantable device that integrates a microfabricated sensing platform, a coil for power and data transmission and integrated circuits. We described a device intended to test the biocompati- bility of the materials used for the microfabrication. Therefore, electronics measurements for data communication and remote powering will be reported in another article [1]. To ensure biocompatibility an epoxy enhanced polyurethane membrane was used to cover the device. We proved through an in-vitro characterization that the membrane was capable to retain enzyme activity up to 35 days. After 30 days of implant in mice, in-vivo experiments proved that the membrane promotes the integration of the sensor with the surrounding tissue, as demonstrated by the low inflammation level at the implant site

2013

Full Fabrication and Packaging of an Implantable Multi-panel Device for Monitoring of Metabolites in Small Animals

Camilla Baj-Rossi, Sandro Carrara, Daniele Casarino, Giovanni De Micheli, Catherine Dehollain, Seyedeh Sara Ghoreishizadeh, Enver Gürhan Kilinç

In this work, we show the realization of a fully-implantable device for monitoring free-moving small animals. The device integrates a microfabricated sensing platform, a coil for power and data transmission and two custom designed integrated circuits. The device is intended to be implanted in mice, free to move in a cage, to monitor the concentration of metabolites. We show the system level design of each block of the device, and we present the fabrication of the passive sensing platform and its employment for the electrochemical detection of endogenous and exogenous metabolites. Moreover, we describe the assembly of the device to test the biocompatibility of the materials used for the microfabrication. To ensure biocompatibility, an epoxy enhanced polyurethane membrane was used to cover the device. We proved through an in-vitro characterization that the membrane was capable to retain enzyme activity up to 35 days. After 30 days of implant in mice, in-vivo experiments proved that the membrane promotes the integration of the sensor with the surrounding tissue, as demonstrated by the low inflammation level at the implant site.

Ieee-Inst Electrical Electronics Engineers Inc2014

Predrilled locking compression plate is more accurate than tension band wiring in restoring articular geometry of the ulnar greater sigmoid notch after olecranon Chevron osteotomy

Alexandre Terrier, Frédéric Vauclair

ELSEVIER SCI LTD2020