INTRODUCTION The rat sciatic nerve crush injury model is commonly employed to evaluate the efficacy of treatments aimed at promoting nerve regeneration. This review examines various crush techniques and the types of nerve injuries they are designed to produce. METHODS A literature review was conducted using PubMed, Embase, Web of Science, and SCOPUS for studies published between 2010 and 2024. Studies were included if they involved surgical crush injuries on the rat sciatic nerve, performed at least one sensory functional evaluation, and compared outcomes with naive or sham controls. Crush techniques and the resulting nerve injuries were analyzed based on postoperative sensory evaluations. RESULTS Of the 48 studies reviewed, 21 met the inclusion criteria. The crush techniques used included clamp (11 studies), forceps (5), clip (4), and others (1), all of which resulted in sensory impairments. Ten studies reported transient impairments with recovery to control levels, while 11 reported no recovery during the observation period (permanent). The transient group had significantly longer observation periods compared to the permanent group (57.7 vs. 17.4 days, p = 0.0009). ROC analysis determined 25 days as the optimal cutoff to distinguish transient from permanent injuries, with 90.0% sensitivity and 81.8% specificity. DISCUSSION Regardless of the technique used, the induced nerve injury aligns with axonotmesis, characterized by spontaneous recovery over time. To accurately evaluate functional recovery, a minimum postoperative observation period of 4 weeks is recommended. This model is best suited for assessing rapid-acting agents, as spontaneous recovery may obscure the effects of slower-acting treatments.

Objectives. Peripheral nerve injuries (PNI) represent the most common type of nervous system injuries, resulting in 5 million injuries per year. Current gold standard, autografts, still carry several limitations, including the inappropriate type, size, and function matches in grafted nerves, lack of autologous donor sites, neuroma formation, and secondary surgery incisions. Polymeric nerve conduits, also known as nerve guides, can help overcome the aforementioned issues that limit nerve recovery and regeneration by reducing tissue fibrosis, misdirection of regenerating axons, and the inability to maintain long- distance axonal growth. Polymer-based double-walled microspheres (DWMSs) are designed to locally and in a sustainable fashion deliver bioactive agents. Lysozyme is a natural antimicrobial protein that shares similar physical and chemical properties to glial cell line-derived neurotrophic factor, making it an ideal surrogate molecule to evaluate the release kinetics of encapsulated bioagent from polymeric biodegradable microspheres embedded in polycaprolactone and polycaprolactone/polyurethane blend nerve conduits. Approach. Lysozyme was encapsulated in poly(lactic-co-glycolic acid)/poly(L-lactide) DWMSs fabricated through a modified water-oil-water emulsion solvent evaporation method. Lysozyme-loaded DWMS were further embedded in PCL and PCL-PU based nerve guides constructed via polymer dip-coating and electrospinning method respectively. Lysozyme DWMS and nerve guides were imaged using scanning electron microscopy (SEM). Released lysozyme concentration was determined by using a colorimetric micro-BCA protein assay and spectrophotometric quantitation. Tensile and suture pull-out tests were utilized to evaluate the mechanical properties of both dip-coated and electrospun nerve guides, embedded and free of lysozyme DWMS. Main results. The study revealed significant distinctions in the lysozyme release profiles, and mechanical properties of the manufactured polymer nerve guides. Both PCL dip-coated and PCL/PU electrospun DWMS-embedded nerve guides revealed biphasic protein release profiles. PCL/PU electrospun and PCL dip-coated nerve guides released 16% and 29% of the total protein concentration within 72 h, plateauing at week 16 and week 8, respectively. SEM analysis of the nerve guides confirmed the homogeneity and integrity of the polymer nerve guides’ structures. The electrospun guides were found to be more flexible with a higher extension under stress bending, while the dip-coated PCL nerve guides displayed more rigid behavior. Significance. This study provides useful insights on how to optimize nerve guide design and fabrication to enhance recovery progress of PNI.

Abstract Non-healing or chronic wounds in extremities that lead to amputations in patients with Type II diabetes (hyperglycemia) are among the most serious and common health problems in the modern world. Over the past decade, more efficient solutions for diabetic ulcers have been developed. Nanofibers and/or composite materials capable of drug delivery, moisture control, and antibacterial effectiveness are increasingly utilized in the formulation of wound dressings, with a particular focus on the biofunctionalization of polymeric and hydrogel materials. Natural products, including plant extracts, honey, antibacterial agents, nanozymes, and metal nanoparticles, are now commonly and effectively implemented to enhance the functionality of wound dressings. Due to the complicated and dysfunctional physiological structure of the chronic wound sites in the extremities of diabetic patients, formulated nanoscaffold or hydrogel components are becoming more intricate and versatile. This study aimed to investigate the development of wound dressing materials over the years while demonstrating their progressively enhanced complexity in effectively targeting, treating, and managing chronic wounds. The mechanisms of action and bio-functionality of wound dressing technologies were elucidated based on findings from 290 studies conducted over the last decade. A notable observation that emerged from these studies is the evolution of wound dressing development technology, which has led to significant advancements in the operational range of smart systems. These include, but are not limited to, self-healing, self-oxygenation, and adaptable mimicry of human tissue.

. Screening for lymphedema and accurate quantitative assessment of dermal backflow patterns on ICG represents a major shift in current clinical practice paradigms, putting an emphasis on early detection of lymphedema rather than palliative treatments and symptomatic relief. These findings set the stage for the development of a practical, universal, ICG-based quantification system for the staging of lymphedema, a significant advancement in the field of plastic surgery.