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Background/Objectives: A pronator quadratus pedicled bone graft (PQPBG) is a distal radius volar vascularized bone graft used not only for avascular necrosis of the lunate but also for scaphoid nonunion. Despite its potency and its possession of a muscular shield, this vascularized graft has a disadvantage in that the potential shortness of the muscular leash may limit the distal transfer of the bone graft. Releasing of the pronator quadratus (PQ) ulnar origin was used to enhance the distal mobility of the graft. We aimed to investigate the effect of a PQ release on the surgical outcomes of scaphoid nonunions that were operated on with the PQPBG technique. Methods: Patients with scaphoid nonunion that were treated with PQPBG from 2009 to 2020 were reviewed. Patient demographic characteristics, surgical notes, physical examinations, and radiological evaluation data were collected. Wrist range of motion, grip strength, modified Mayo wrist score, and Quick-DASH score were used to evaluate the outcomes. The included patients were divided into two groups based on the origin release status of their PQ, i.e., with and without release. Results: This study included 37 patients, 17 of whom underwent a PQ release and 20 of whom did not. The failure rates for the two groups were one and four patients, respectively, and there was no significant difference between them (p = 0.11). The postoperative mean wrist extension in the patients with a PQ release was significantly greater than that in the patients without a release (43.5 ± 6.8 vs. 36.5 ± 7.7, p = 0.0038). Although wrist flexion, ulnar deviation, radial deviation, mean outcome assessment scores, and grip strength were greater in the patients with a PQ release than in those without, no statistically significant intergroup differences were observed (p > 0.05). Conclusions: The PQPBG technique is a viable option for achieving bony union in patients with scaphoid nonunion, but it results in the postoperative restriction of wrist extension. PQ release during a graft transfer may have a favorable effect on both bone union and clinical outcomes. [ABSTRACT FROM AUTHOR]

Background/Objectives: We sought to improve accuracy while minimizing radiation hazards, improving surgical outcomes, and preventing potential complications. Despite the increasing popularity of these systems, a limited number of papers have been published addressing the historical evolution, detailing the areas of use, and discussing the advantages and disadvantages, of this increasingly popular system in lumbar spine surgery. Our objective was to offer readers a concise overview of navigation system history in lumbar spine surgeries, the techniques involved, the advantages and disadvantages, and suggestions for future enhancements to the system. Methods: A comprehensive review of the literature was conducted, focusing on the development and implementation of navigation systems in lumbar spine surgeries. Our sources include PubMed-indexed peer-reviewed journals, clinical trial data, and case studies involving technologies such as computer-assisted surgery (CAS), image-guided surgery (IGS), and robotic-assisted systems. Results: To develop more practical, effective, and accurate navigation techniques for spine surgery, consistent advancements have been made over the past four decades. This technological progress began in the late 20th century and has since encompassed image-guided surgery, intraoperative imaging, advanced navigation combined with robotic assistance, and artificial intelligence. These technological advancements have significantly improved the accuracy of implant placement, reducing the risk of misplacement and related complications. Navigation has also been found to be particularly useful in tumor resection and minimally invasive surgery (MIS), where conventional anatomic landmarks are lacking or, in the case of MIS, not visible. Additionally, these innovations have led to shorter operative times, decreased radiation exposure for patients and surgical teams, and lower rates of reoperation. As navigation technology continues to evolve, future innovations are anticipated to further enhance the capabilities and accessibility of these systems, ultimately leading to improved patient outcomes in lumbar spine surgery. Conclusions: The initial limited utilization of navigation system in spine surgery has further expanded to encompass almost all fields of lumbar spine surgeries. As the cost-effectiveness and number of trained surgeons improve, a wider use of the system will be ensured so that the navigation system will be an indispensable tool in lumbar spine surgery. However, continued research and development, along with training programs for surgeons, are essential to fully realize the potential of these technologies in clinical practice. [ABSTRACT FROM AUTHOR]

The feasibility of implementing digital predistortion for next-generation wireless communication is faced with a dilemma due to the ever-increasing demand for faster data rates. This causes the utilized bandwidth to increase significantly, as seen in the 5G NR standard in which bandwidths as high as 400 MHz are utilized. Hence, the development of new predistortion techniques in which the forward and feedback paths operate at lower sampling rates is of utmost importance to realize efficient and practical predistortion solutions. In this work, a novel predistortion technique is presented by which the predistortion is divided between the digital and analog domains. The predistorter is composed of a memoryless AM/AM gain function that is implementable in the analog domain, and a nonlinear model with memory effects in the digital domain to relax the sampling rate requirements on both the forward and feedback paths. Experimental validation was carried out with a 20 MHz and a 40 MHz 5G signal, and the results indicate minimal linearization degradation with a sampling rate reduction of 50% and 30%, respectively. This sampling rate reduction is concurrently applied in the digital-to-analog converter of the forward path and the analog-to-digital converter of the feedback path. [ABSTRACT FROM AUTHOR]

Background: The aging of the population in developing and developed countries has led to a significant increase in the health burden of spinal diseases. These elderly patients often have a number of medical comorbidities due to aging. The need for minimally invasive techniques to address spinal disorders in this elderly population group cannot be stressed enough. Minimally invasive spine surgery (MISS) has several proven benefits, such as minimal muscle trauma, minimal bony resection, lesser postoperative pain, decreased infection rate, and shorter hospital stay. Methods: A comprehensive search of the literature was performed using PubMed. Results: Over the past 40 years, constant efforts have been made to develop newer techniques of spine surgery. Endoscopic spine surgery is one such subset of MISS, which has all the benefits of modern MISS. Endoscopic spine surgery was initially limited only to the treatment of lumbar disc herniation. With improvements in optics, endoscopes, endoscopic drills and shavers, and irrigation pumps, there has been a paradigm shift. Endoscopic spine surgery can now be performed with high magnification, thus allowing its application not only to lumbar spinal stenosis but also to spinal fusion surgeries and cervical and thoracic pathology as well. There has been increasing evidence in support of these newer techniques of spine surgery. Conclusions: For this report, we studied the currently available literature and outlined the historical evolution of endoscopic spine surgery, the various endoscopic systems and techniques available, and the current applications of endoscopic techniques as an alternative to traditional spinal surgery. [ABSTRACT FROM AUTHOR]