The Cartiva implant is a synthetic polyvinyl alcohol hydrogel cartilage substitute that is used as a treatment of first metatarsophalangeal joint arthritis. The implant was designed to relieve the pain associated with hallux rigidus while preserving or restoring range of motion. A summary of outcomes, reasons for these outcomes, and technique pearls will be reviewed here. Seminal articles and current evidence are all included in this article. The aim is for the surgeon to understand all the literature, allowing the surgeon to counsel their patients appropriately, optimize patient selection and to deal with complications.

In recent years, the development of environmentally friendly packaging materials using biodegradable polymers has emerged as a key challenge for scientists and consumers in response to resource depletion and environmental issues caused by plastic packaging materials. Starch and polyvinyl alcohol (PVA) are being recognized as excellent candidates for producing biodegradable food packaging films. Polymer blending has emerged as a practical approach to overcome the limitations of biopolymer films by developing films with unique properties and enhancing overall performance. This review briefly introduces the molecular structure and properties of starch and PVA, summarizes the common preparation methods and properties of starch/PVA blend films, and focuses on different strategies used to enhance starch/PVA blend films, including nanoparticles, plant extracts, and cross-linking agents. Additionally, this study summarizes the application of starch/PVA blend films as active and smart packaging in food preservation systems. This study demonstrates that starch and PVA blends have potential in manufacturing biodegradable food films with excellent properties due to their excellent compatibility and intermolecular interactions, and can be used as packaging films for a variety of foods to extend their shelf life.

Chronic subdural hematoma (c-SDH) is a frequent and serious neurological disease. It develops due to hemorrhage to the subdural space, mainly caused by head trauma. The middle meningeal artery (MMA) plays a critical role in the supply of blood to c-SDH. The decision on the type of treatment for c-SDH depends mainly on clinical and imaging evaluation. In cases in which patients are critically ill, the hematoma must be evacuated immediately. For this purpose, surgery is generally accepted as the mainstay of treatment. Among surgical techniques, twist-drill craniotomy, burr-hole craniotomy, and craniotomy are the three most used. The recurrence rate of c-SDH after surgery is an important problem with a rate of up to 30%. The technical success classification embolization of MMA (EMMA) has emerged as an effective and safe option for the treatment of c-SDH, especially those that recur. EMMA is commonly used as an adjunct to surgery or less frequently alone. The technical success of EMMA has been a promising minimal invasive strategy as an alternative or adjunctive therapy to surgical methods. Polyvinyl alcohol is the most widely used among various embolizing agents, including n-butyl cyanoacrylate, coil, and gelatin sponge. EMMA has been shown to prevent the formation or recurrence of c-SDH by eliminating blood flow to the subdural space. Complication rates are low. The large-scale comparative prospective will ensure efficacy and safety. This article aims to highlight the current information about EMMA in patients with c-SDH.

OBJECTIVE: Moderate-to-severe hallux rigidus is a debilitating pathology that is optimally treated with surgical intervention. Arthrodesis produces reliable clinical outcomes but is limited by restriction in 1st metatarsophalangeal joint range of motion. The advent of polyvinyl alcohol hydrogel (PVA) implants have produced early promise based on initial trials, but more recent studies have called into question the efficacy of this procedure. The purpose of this systematic review was to evaluate the clinical and radiological outcomes following the use of PVA for hallux rigidus.
METHODS: The MEDLINE, EMBASE and Cochrane library databases were systematically reviewed using the preferred reporting items for systematic reviews and meta-analyses guidelines. 18 studies were included.
RESULTS: In total, 1349 patients (1367 feet) underwent PVA at a weighted mean follow-up of 24.1 ± 11.1 months. There were 168 patients (169 feet) included in the cheilectomy cohort and 322 patients (322 feet) included in the arthrodesis cohort. All 3 cohorts produced comparable improvements in subjective clinical outcomes. Postoperative imaging findings in the PVA cohort included joint space narrowing, peri-implant fluid, peri-implant edema and erosion of the proximal phalanx. The complication rate in the PVA cohort, cheilectomy cohort and arthrodesis cohort was 27.9%, 11.8% and 24.1%, respectively. The failure rates in the PVA cohort, cheilectomy cohort and arthrodesis cohort was 14.8%, 0.3% and 9.0%, respectively.
CONCLUSIONS: This systematic review demonstrated that PVA produced a high complication rate (27.9%) together with concerning postoperative imaging findings at short-term follow-up. In addition, a moderate failure rate (14.8%) and secondary surgical procedure rate (9.5%) was noted for the PVA cohort. The findings of this review calls into question the efficacy and safety of PVA for the treatment of hallux rigidus.
METHODS: IV.

Electrospinning has been acknowledged as an efficient technique for the fabrication of continuous nanofibers from polymeric based materials such as polyvinyl alcohol (PVA), cellulose acetate (CA), chitin nanocrystals and others. These nanofibers exhibit chemical and mechanical stability, high porosity, functionality, high surface area and one-dimensional orientation which make it extremely beneficial in industrial application. In recent years, research on chitin - a biopolymer derived from crustacean and fungal cell wall - had gained interest due to its unique structural arrangement, excellent physical and chemical properties, in which make it biodegradable, non-toxic and biocompatible. Chitin has been widely utilized in various applications such as wound dressings, drug delivery, tissue engineering, membranes, food packaging and others. However, chitin is insoluble in most solvents due to its highly crystalline structure. An appropriate solvent system is required for dissolving chitin to maximize its application and produce a fine and smooth electrospun nanofiber. This review focuses on the preparation of chitin polymer solution through dissolution process using different types of solvent system for electrospinning process. The effect of processing parameters also discussed by highlighting some representative examples. Finally, the perspectives are presented regarding the current application of electrospun chitin nanofibers in selected fields.

Poly(vinyl alcohol) is one of the most attractive polymers with a wide range of uses because of its water solubility, biocompatibility, low toxicity, good mechanical properties, and relatively low cost. This review article focuses on recent advances in poly(vinyl alcohol) electrospinning and summarizes parameters of the process (voltage, distance, flow rate, and collector), solution (molecular weight and concentration), and ambient (humidity and temperature) in order to comprehend the influence on the structural, mechanical, and chemical properties of poly(vinyl alcohol)-based electrospun matrices. The importance of poly(vinyl alcohol) electrospinning in biomedical applications is emphasized by exploring a literature review on biomedical applications including wound dressings, drug delivery, tissue engineering, and biosensors. The study also highlights a new promising area of particles formation through the electrospraying of poly(vinyl alcohol). The limitations and advantages of working with different poly(vinyl alcohol) matrices are reviewed, and some recommendations for the future are made to advance this field of study.

Hallux rigidus is the most frequent arthritis of the foot, due to multiple factors. Arthrodesis and interposition arthroplasty are treatments considered in advanced stages of the disease, when conservative treatment has failed. Although arthrodesis may be considered the technique recommended by multiple authors, for patients in whom joint mobility is to be preserved, arthroplasty could represent a reliable alternative. The purpose of this systematic review is to investigate and compare the clinical outcomes and complications of arthrodesis and interposition arthroplasty for moderate and severe stages of hallux rigidus.
METHODS: For this systematic review we searched COCHRANE, EMBASE, PUBMED databases. Twenty-six research papers were obtained, with a total of 1348 feet, which were included for qualitative analysis. The following groups were included: Cartiva hemiarthroplasty (286), double stem silicone arthroplasty (276), total metallic arthroplasty (394) and arthrodesis (392).
RESULTS: In the arthrodesis group, the AOFAS-HMI score was the most used, ranging from 36 to 45 in the preoperative period and from 79 to 89 in the postoperative period. The greatest improvement in the VAS PAIN score was from 86 to 4. The fusion rate was 98.6% of the total number of cases, the most frequent complication was pain due to material discomfort. In the total metallic arthroplasty group, the ROTO-GLIDE system reported an AOFAS score of 95 points, with low complication rates; but, with the TOEFIT-PLUS and BIOMED-MERCK systems, despite the good postoperative value, they report 37% and 15% revision due to aseptic loosening in the series with the longest follow-up, respectively. The Cartiva group showed a significative increase in FAAM ADL and FAAM SPORT from 59.4 to 90.4 and from 60.9 to 89.7, respectively; similarly, 20.5% implant removal and conversion to arthrodesis were reported. Finally, the double stem silicone arthroplasty group, in the series with the longest follow-up, it manages to improve the MOXFQ score from 78.1 to 11.0, with an average range of mobility of 22.3 degrees. Lysis was reported in 10% of cases.
CONCLUSIONS: Arthrodesis has proven to be the best option for the treatment of advanced hallux rigidus. Arthroplasty can be a valid option for patients who demand to maintain the range of mobility of the joint; however, it is important to inform about the complications that may arise in the short and medium term.
METHODS: II.

Hydrogels is a hydrophilic, cross-linked polymer of three-dimensional network structures. The application of hydrogels prepared from a single polymer in the biomedical field has many drawbacks. The functional blend of polyvinyl alcohol and chitosan allows hydrogels to have better and more desirable properties than those produced from a single polymer, which is a good biomaterial for development and design. In this paper, we have reviewed the progress in the application of polyvinyl alcohol/chitosan composite hydrogels in various medical fields, the different cross-linking agents and cross-linking methods, and the research progress in the optimization of composite hydrogels for their subsequent wide range of biomedical applications.

Tissue engineering and regenerative medicine (TERM) holds great promise for addressing the growing need for innovative therapies to treat disease conditions. To achieve this, TERM relies on various strategies and techniques. The most prominent strategy is the development of a scaffold. Polyvinyl alcohol-chitosan (PVA-CS) scaffold emerged as a promising material in this field due to its biocompatibility, versatility, and ability to support cell growth and tissue regeneration. Preclinical studies showed that the PVA-CS scaffold can be fabricated and tailored to fit the specific needs of different tissues and organs. Additionally, PVA-CS can be combined with other materials and technologies to enhance its regenerative capabilities. Furthermore, PVA-CS represents a promising therapeutic solution for developing new and innovative TERM therapies. Therefore, in this review, we summarized the potential role and functions of PVA-CS in TERM applications.

Presently, the rising concerns about the fossil fuel crisis and ecological deterioration have greatly affected the world economy and hence have attracted attention to the utilization of renewable energies. Among the renewable energy being developed, supercapacitors hold great promise in broad applications such as electric vehicles. Presently, the main challenge facing supercapacitors is the amount of energy stored. This, however, does not satisfy the increasing demand for higher energy storage devices, and therefore, intensive research is being undertaken to overcome the challenges of low energy density. The purpose of this review is to report on solid polymer electrolytes (SPEs) based on polyvinyl alcohol (PVA). The review discussed the PVA as a host polymer in SPEs followed by a discussion on the influence of conducting salts. The formation of SPEs as well as the ion transport mechanism in PVA SPEs were discussed. The application and development of PVA-based polymer electrolytes on supercapacitors and other energy storage devices were elucidated. The fundamentals of electrochemical characterization for analyzing the mechanism of supercapacitor applications, such as EIS, LSV and dielectric constant, are highlighted. Similarly, thermodynamic transport models of ions and their mechanism about temperature based on Arrhenius and Vogel-Tammann-Fulcher (VTF) are analyzed. Methods for enhancing the electrochemical performance of PVA-based SPEs were reported. Likely challenges facing the current electrolytes are well discussed. Finally, research directions to overcome the present challenges in producing SPEs are proposed. Therefore, this review is expected to be source material for other researchers concerned with the development of PVA-based SPE material.