Continuous Femoral Catheter for Postoperative Analgesia After Total Knee Arthroplasty.

INTRODUCTION: Postoperative pain management in the total knee replacement (TKR) represent a fundamental step for a positive outcome, allowing rapid mobilization, already on the first day. Further, continuous peripheral nerve block techniques have been reported to allow effective and safe control of acute postoperative pain, ensuring the implementation and completion of an accurate and intensive joint rehabilitation program. AIM: The aim of this study was to assess early mobility and compliance of patients that underwent TKR surgery using the femoral block. METHODS: For the study, all patients that underwent TKR from 2015 to 2018 with ASA score between II-III was evaluated. Patients underwent vital parameters monitoring and were treated initially with midazolam (0.05mg / kg) e.v. combined sciatic block + femoral perineural catheter positioning using a peripheral nerve stimulation-assisted technique. RESULTS: Intraoperatively, satisfactory analgesia was guaranteed in all patients, associated with a complete muscle relaxation of the affected limb. High patient compliance, associated with good control of acute postoperative pain was obtained in the first 24 hours after surgery (VAS 0- 1). The ROM outcomes were good in all rehabilitation stages, managing to reach 90 degrees bending on the seventh day with an average KSS score of 88-90. Patient satisfaction and impact on quality of life were assessed with the SF-36 showing average scores of 78. CONCLUSION: Continuous femoral nerve blocking ensures good postoperative analgesia in TKR allowing an early joint mobilization, a rapid functional recovery of the knee and increasing patient compliance during the post-operative rehabilitation program.

On the development of a biomechatronic system to record tendon sliding movements.

The main goal of this paper is to study the feasibility of a novel implantable micro-system able to record information about tendon sliding movements by using contactless measurement devices (magnetic sources and sensors). The system, named "Biomechatronic Position Transducer" (BPT), can be used for the implementation of advanced control strategies in neuroprostheses. After a preliminary analysis based on finite element model simulations, an experimental setup was developed in order to simulate the recording conditions (the sensors fixed to the bones and the magnetic sources placed on the tendons). In order to limit the number of implanted components of the system, a fuzzy Mamdani-like architecture was developed to extract the information from the raw data. The results confirm the possibility of using the presented approach for developing an implantable micro-sensor able to extract kinematic information useful for the control of neuroprostheses. Future works will go in the direction of integrating and testing the sensors and the electronic circuitry (to provide power supply and to record the data) during in vitro and in situ experiments.