Molecular and Biologic Effects of Platelet-Rich Plasma (PRP) in Ligament and Tendon Healing and Regeneration: A Systematic Review

Platelet-rich plasma (PRP) has been introduced and applied to a wide spectrum of acute and chronic ligament and tendon pathologic conditions. Although the biological effect of PRP has been studied thoroughly in both animal and human studies, there is no consensus so far on the exact mechanism of its action as well as the optimal timing and dosage of its application. Therefore, we conducted a systematic review aiming to evaluate the molecular effect of the administration of PRP in tendoligamentous injuries and degenerative diseases. The literature search revealed 36 in vitro and in vivo studies examining the healing and remodeling response of animal and human ligament or tendon tissues to PRP. Platelet-rich plasma added in the culture media was highly associated with increased cell proliferation, migration, viability and total collagen production of both ligament- and tendon-derived cells in in vitro studies, which was further confirmed by the upregulation of collagen gene expression. In vivo studies correlated the PRP with higher fibroblastic anabolic activity, including increased cellularity, collagen production and vascularity of ligament tissue. Similarly, greater metabolic response of tenocytes along with the acceleration of the healing process in the setting of a tendon tear were noticed after PRP application, particularly between the third and fourth week after treatment. However, some studies demonstrated that PRP had no or even negative effect on tendon and ligament regeneration. This controversy is mainly related to the variable processes and methodologies of preparation of PRP, necessitating standardized protocols for both investigation and ap-plication

Segmental meniscal replacement

Meniscal damage results in higher peak stress on the articular cartilage and leads to cartilage degeneration and osteoarthritis. Thus, in recent years there has been an increasing tendency to “save the meniscus” and to repair meniscal defects. However, this is not always possible and restoring meniscal function using scaffolds fulfills this gap. This approach requires the physical presence of an artificial meniscus to allow successful migration and colonization with precursor cells and vessels that lead to the development of organized meniscal tissue. Two meniscal scaffolds are currently available; 1 composed of aliphatic polyurethane named Actifit (Orteq Sports Medicine, Ltd.), and one based on collagen type I fibers called Collagen Meniscus Implant (Stryker Kalamazoo). Both provide an effective and safe solution to treat symptomatic patients with segmental meniscus mid-substance defects. Indeed, recent studies have demonstrated their ability to significantly improve patient satisfaction and clinical evaluation in the mid- to long-term. As such, these approaches hold great promise as a meniscus preservation option to facilitate long-term knee health

Satisfactory outcomes of patellar tendon reconstruction using achilles’ tendon allograft with bone block after infected total knee arthroplasty

Purpose: Extensor mechanism disruption is an uncommon and devastating complication after total knee arthroplasty. It negatively affects patients’ quality of life and leads to significant functional limitations and the inability to stand and walk. The purpose of the present study was to evaluate the outcomes of the extensor mechanism reconstruction using Achilles’ tendon allograft after infected total knee arthroplasty. It was hypothesized that it is a safe procedure and that patients will present good clinical and functional results. Methods: Ten patients treated for infra-patellar extensor mechanism disruption after infected total knee arthroplasty were prospectively followed for two years. The mean age of patients was 70.8 (range 55–85), with a median BMI of 28.72 ± 2.2 kg/m2. All patients underwent reconstruction using a fresh frozen Achilles tendon allograft. Preoperative and postoperative evaluation included knee-related clinical and functional assessment based on objective and subjective scores, including the knee flexion, the extension lag, the Knee Society Score (KSS) clinical and functional, and the visual analog scale (VAS) for pain at 12 and 24 months. Radiological evaluation was also performed using the Caton-Deschamps index. Reported complications were also recorded. Results: Clinical and functional outcomes recorded significant improvements (p < 0.05) at the final follow-up compared with baseline as follows: Knee flexion was improved from 66° ± 4.8 to 99.7° ± 3.9, and the extension lag was decreased from 28.3° ± 4.4 to 9° ± 2.7. The mean KSS clinical and functional were also improved from 22.6 ± 7.9 to 73.4 ± 3.9 and from 10 ± 13.8 to 55 ± 13.8, respectively. The VAS for pain was decreased from 8.1 ± 1.2 to 1.9 ± 1.2. The Caton-Deschamps index demonstrated a tendency to patella Alta. Two treatment failures were recorded, one patellar dislocation and one re-rupture revised to arthrodesis. Conclusions: Extensor mechanism reconstruction using Achilles’ tendon allograft after infected total knee arthroplasty is an efficient and safe procedure for infra-patellar disruption. The present study’s findings demonstrate that most of the patients (80%) presented significant clinical and functional improvement at two-year follow-up.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Satisfactory outcomes of patellar tendon reconstruction using achilles’ tendon allograft with bone block after infected total knee arthroplasty

Abstract Purpose Extensor mechanism disruption is an uncommon and devastating complication after total knee arthroplasty. It negatively affects patients’ quality of life and leads to significant functional limitations and the inability to stand and walk. The purpose of the present study was to evaluate the outcomes of the extensor mechanism reconstruction using Achilles’ tendon allograft after infected total knee arthroplasty. It was hypothesized that it is a safe procedure and that patients will present good clinical and functional results. Methods Ten patients treated for infra‐patellar extensor mechanism disruption after infected total knee arthroplasty were prospectively followed for two years. The mean age of patients was 70.8 (range 55–85), with a median BMI of 28.72 ± 2.2 kg/m2. All patients underwent reconstruction using a fresh frozen Achilles tendon allograft. Preoperative and postoperative evaluation included knee‐related clinical and functional assessment based on objective and subjective scores, including the knee flexion, the extension lag, the Knee Society Score (KSS) clinical and functional, and the visual analog scale (VAS) for pain at 12 and 24 months. Radiological evaluation was also performed using the Caton‐Deschamps index. Reported complications were also recorded. Results Clinical and functional outcomes recorded significant improvements (p < 0.05) at the final follow‐up compared with baseline as follows: Knee flexion was improved from 66° ± 4.8 to 99.7° ± 3.9, and the extension lag was decreased from 28.3° ± 4.4 to 9° ± 2.7. The mean KSS clinical and functional were also improved from 22.6 ± 7.9 to 73.4 ± 3.9 and from 10 ± 13.8 to 55 ± 13.8, respectively. The VAS for pain was decreased from 8.1 ± 1.2 to 1.9 ± 1.2. The Caton‐Deschamps index demonstrated a tendency to patella Alta. Two treatment failures were recorded, one patellar dislocation and one re‐rupture revised to arthrodesis. Conclusions Extensor mechanism reconstruction using Achilles’ tendon allograft after infected total knee arthroplasty is an efficient and safe procedure for infra‐patellar disruption. The present study’s findings demonstrate that most of the patients (80%) presented significant clinical and functional improvement at two‐year follow‐up

Stem cells for the treatment of early to moderate osteoarthritis of the knee: a systematic review

Abstract Purpose Mesenchymal stem cells (MSCs) present a valuable treatment option for knee osteoarthritis with promising results. The purpose of the present study was to systematically review the clinical and functional outcomes following mesenchymal stem cell application focusing on early to moderate knee osteoarthritis. Methods A systematic search was done using the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines in Pubmed, Scopus, Web of Science, and Cochrane Library databases. All Studies published between 2017 and March 2023 on patients treated with single mesenchymal stem cell injection for Kellgren‐Lawrence grade I—III knee osteoarthritis reported on clinical and functional outcomes were included. Results Twelve articles comprising 539 patients and 576 knees treated with a single intraarticular injection of MSCs for knee osteoarthritis were included in the current systematic review. In eligible studies, the reported outcomes were improved concerning patient‐reported outcomes measures, knee function, pain relief, and quality of patient's life. Conclusion Based on high‐level evidence studies, single intraarticular injection of MSCs is a safe, reliable, and effective treatment option for Kellgren‐Lawrence grade I—III knee osteoarthritis. However, the lack of homogeneity in the included studies and the variance in MSCs sources and preparations should be noted. Level of evidence III

Stem cells for the treatment of early to moderate osteoarthritis of the knee: a systematic review

Purpose: Mesenchymal stem cells (MSCs) present a valuable treatment option for knee osteoarthritis with promising results. The purpose of the present study was to systematically review the clinical and functional outcomes following mesenchymal stem cell application focusing on early to moderate knee osteoarthritis. Methods: A systematic search was done using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in Pubmed, Scopus, Web of Science, and Cochrane Library databases. All Studies published between 2017 and March 2023 on patients treated with single mesenchymal stem cell injection for Kellgren-Lawrence grade I—III knee osteoarthritis reported on clinical and functional outcomes were included. Results: Twelve articles comprising 539 patients and 576 knees treated with a single intraarticular injection of MSCs for knee osteoarthritis were included in the current systematic review. In eligible studies, the reported outcomes were improved concerning patient-reported outcomes measures, knee function, pain relief, and quality of patient's life. Conclusion: Based on high-level evidence studies, single intraarticular injection of MSCs is a safe, reliable, and effective treatment option for Kellgren-Lawrence grade I—III knee osteoarthritis. However, the lack of homogeneity in the included studies and the variance in MSCs sources and preparations should be noted. Level of evidence: III.SCOPUS: re.jinfo:eu-repo/semantics/publishe