Tissue engineering and future directions in regenerative medicine for knee cartilage repair: a comprehensive review.

This review evaluates the current landscape and future directions of regenerative medicine for knee cartilage repair, with a particular focus on tissue engineering strategies. In this context, scaffold-based approaches have emerged as promising solutions for cartilage regeneration. Synthetic scaffolds, while offering superior mechanical properties, often lack the biological cues necessary for effective tissue integration. Natural scaffolds, though biocompatible and biodegradable, frequently suffer from inadequate mechanical strength. Hybrid scaffolds, combining elements of both synthetic and natural materials, present a balanced approach, enhancing both mechanical support and biological functionality. Advances in decellularized extracellular matrix scaffolds have shown potential in promoting cell infiltration and integration with native tissues. Additionally, bioprinting technologies have enabled the creation of complex, bioactive scaffolds that closely mimic the zonal organization of native cartilage, providing an optimal environment for cell growth and differentiation. The review also explores the potential of gene therapy and gene editing techniques, including CRISPR-Cas9, to enhance cartilage repair by targeting specific genetic pathways involved in tissue regeneration. The integration of these advanced therapies with tissue engineering approaches holds promise for developing personalized and durable treatments for knee cartilage injuries and osteoarthritis. In conclusion, this review underscores the importance of continued multidisciplinary collaboration to advance these innovative therapies from bench to bedside and improve outcomes for patients with knee cartilage damage.

Mesenchymal Stem Cell Mechanisms of Action and Clinical Effects in Osteoarthritis: A Narrative Review.

With the insufficient satisfaction rates and high cost of operative treatment for osteoarthritis (OA), alternatives have been sought. Furthermore, the inability of current medications to arrest disease progression has led to rapidly growing clinical research relating to mesenchymal stem cells (MSCs). The availability and function of MSCs vary according to tissue source. The three primary sources include the placenta, bone marrow, and adipose tissue, all of which offer excellent safety profiles. The primary mechanisms of action are trophic and immunomodulatory effects, which prevent the further degradation of joints. However, the function and degree to which benefits are observed vary significantly based on the exosomes secreted by MSCs. Paracrine and autocrine mechanisms prevent cell apoptosis and tissue fibrosis, initiate angiogenesis, and stimulate mitosis via growth factors. MSCs have even been shown to exhibit antimicrobial effects. Clinical results incorporating clinical scores and objective radiological imaging have been promising, but a lack of standardization in isolating MSCs prevents their incorporation in current guidelines.

Long-term Clinical Outcomes Following Endoscopic Foraminoplasty for Patients With Single-Level Foraminal Stenosis of the Lumbar Spine.

BACKGROUND: The aim of this study is to evaluate the safety and long-term clinical outcomes of transforaminal endoscopic foraminoplasty using local anesthesia and total intravenous analgesia (TIVA) in patients with single-level lumbar foraminal stenosis and unilateral leg pain. METHODS: Postoperative pain relief was self-evaluated by 46 consecutive patients using a visual analog scale (VAS) and Oswestry Disability Index (ODI). Patient scores were obtained before the procedure and at 6, 12, 24, and 60 months after surgery. RESULTS: Pain reduction of at least 50% in the VAS score and a decrease of at least 50% or more in ODI score was achieved in 37 of 46 patients throughout the follow-up period. Median VAS score decreased from 7.5 preoperatively to 2.5 postoperatively. Median ODI score decreased from 62% preoperatively to 15% postoperatively. All patients reached 24-month follow-up and 37 patients reached 60-month follow-up. There were no surgery-related complications. CONCLUSION: Transforaminal endoscopic foraminoplasty performed under local anesthesia and TIVA produces sustained reduction in pain and improves functionality in patients with single-level lumbar foraminal stenosis without complications even in patients with comorbidities. CLINICAL RELEVANCE: Endoscopic foraminoplasty may be a useful adjunct to open micro decompressive surgery for patients with foraminal stenosis of the lumbar spine LEVEL OF EVIDENCE: 4.