Clinical Update: Why PRP Should Be Your First Choice for Injection Therapy in Treating Osteoarthritis of the Knee

Platelet-Rich Plasma for Knee and Hip Osteoarthritis Pain: A Scoping Review

PURPOSE OF REVIEW

Platelet-rich plasma (PRP) is an emerging biological intervention for osteoarthritis (OA), yet the outcomes remain uncertain. The purpose of this study was to review current literature regarding the use of PRP for knee and hip OA.

RECENT FINDINGS

Recent systematic reviews have found significant clinical improvements in outcomes after the administration of PRP compared to hyaluronic acid (HA) in patients with knee OA. One of these reviews included bone marrow aspirate concentrate (BMAC) as a comparison group and found no significant differences in outcomes between PRP and BMAC. Currently, the literature is lacking on whether leukocyte-rich or leukocyte-poor PRP is superior in patients with knee OA. The literature on PRP for hip OA has not provided consistent results as it has for the knee. Two recent systematic reviews evaluated RCTs for patients undergoing treatment with either PRP or HA for hip OA and found no significant differences in clinical outcomes between groups at final follow-up. Current literature regarding the association between OA grade and PRP efficacy has found varying results. The use of PRP injections in the treatment of knee OA appears to be favorable, resulting in clinically comparable or superior outcomes compared to other injection treatments. However, the clinical efficacy of PRP injections in hip OA is far less consistent. Evidence is lacking to suggest that the presence of leukocytes significantly influences clinical outcomes. Further randomized controlled trials on larger cohorts, with longer follow-up, and with comparable formulations are required before recommendations can be made regarding use of PRP for hip OA, the effect of leukocyte concentration, and clinical efficacy based on OA grade.

Editorial Commentary: High-Platelet-Dose Platelet-Rich Plasma May Be the Nonoperative Treatment of Choice for Knee Osteoarthritis

Knee osteoarthritis (OA) affects 30% of individuals older than 60 and 40% older than 70 years old. The incidence of radiologic knee OA is 373 per 10,000 person-years, but symptomatic knee OA registers at a considerably lower rate of 50 per 10,000 person-years. For symptomatic cases that are not candidates for surgical intervention, various treatment options include exercise, weight loss, pharmacologic management, bracing, physical therapy, oral supplementation, and intra-articular injection with corticosteroids, hyaluronic acid, or orthobiologics such as platelet-rich plasma (PRP). Recent network meta-analysis has affirmed the superiority of PRP over the other alternatives. It appears that a mean absolute platelet count in the final product of less than 2,500 × 106 is not effective, whereas an average platelet count of greater than 5,000 × 106 displays a positive clinical effect at both 6 and 12 months. Yet, aspects like the definition of PRP, whether activation is necessary, the frequency of injections, the optimal dosage, and the preparation method remain unclear.

Microfragmented Adipose Tissue Is Equivalent to Platelet-Rich Plasma for Knee Osteoarthritis at 12 Months Posttreatment: A Randomized Controlled Trial

Background

Platelet-rich plasma (PRP) is an effective treatment for knee osteoarthritis (OA). Microfragmented adipose tissue (MFAT) is another orthobiologic that holds promise, but data supporting its use are limited. Previous studies showed that MFAT created using the Lipogems device was equivalent to PRP created via noncommercial laboratory-based processes.

Purpose

To perform a comparison of commercially available MFAT and PRP systems for treatment of knee OA.

Study Design

Randomized controlled trial; Level of evidence, 2.

Methods

A total of 71 patients with symptomatic knee OA (Kellgren-Lawrence grades 1-4) were randomized to receive a single injection of either leukocyte-rich PRP (Angel; Arthrex) or MFAT (Lipogems) under ultrasound guidance. Patient-reported outcomes (Knee injury and Osteoarthritis Outcome Score [KOOS], visual analog scale for pain with activities of daily living [VAS pain], and Tegner activity level) were recorded at baseline and at 1, 3, 6, and 12 months after injection. The primary outcome was the KOOS-Pain subscale score at 12 months after injection.

Results

Overall, 49 patients completed their 12-month follow-up (PRP group, n = 23; MFAT group, n = 26). All demographic features were similar between groups, except that more men were randomized to the PRP group and more women to the MFAT group. At 12 months posttreatment, KOOS-Pain scores improved in both groups, with no significant group difference (PRP, 78 ± 17.9 vs MFAT, 77.8 ± 19.3; P = .69). Similarly, other KOOS subscales, VAS pain scores, and Tegner scores improved at 12 months, with no differences between treatment groups.

Conclusion

Both PRP and MFAT injections for knee OA resulted in improved patient-reported outcomes at 12 months posttreatment, with no differences found between treatments.

Registration

NCT04351087 (ClinicalTrials.gov identifier).

Clinical Outcome of Multiple Platelet-Rich Plasma Injection and Correlation with PDGF-BB in the Treatment of Knee Osteoarthritis

(1) Background: Current treatments for knee osteoarthritis (KOA), such as intra-articular corticosteroids or hyaluronic acid (HA) injections, are controversial due to their ineffectiveness in preventing disease progression. Platelet-rich plasma (PRP) has become a promising and possible treatment for KOA. It is thought to enhance articular cartilage regeneration and reduce OA-related impairment. PRP contains growth factors such as PDGF-BB, which stimulates growth and inhibits joint damage. Based on numerous studies, after a certain amount of time, it was found that multiple PRP treatments reduced pain more than a single injection. This study evaluates the efficacy of multiple PRP (m-PRP) injections compared to multiple HA (m-HA) injections for KOA treatment, focusing on their correlation with PDGF-BB levels. (2) Methods: In this single-center, open-label, randomized, comparative clinical trial, 30 KOA patients received m-PRP and m-HA injections. VAS and WOMAC were used to evaluate clinical outcomes and PDGF-BB concentrations. (3) Results: The study analysis revealed a statistically significant reduction in pain indices. In both the m-PRP and m-HA groups after 12 weeks, m-PRP showed superior results. PDGF-BB concentrations also increased, with a strong negative correlation and statistical significance using Spearman's rho. (4) Conclusions: Multiple PRP injections are safe and associated with elevated PDGF-BB, reduced VAS and WOMAC scores, providing the potential for articular cartilage regeneration and inhibiting knee osteoarthritis progression.

Application of Platelet-Rich Plasma as a Stem Cell Treatment - an Attempt to Clarify a Common Public Misconception

In recent years, there has been a significant increase in the practice of regenerative medicine by health practitioners and direct-to-consumer businesses globally. Among different tools of regenerative medicine, platelet-rich plasma (PRP) and stem cell-based therapies have received considerable attention. The use of PRP, in particular, has gained popularity due to its easy access, simple processing techniques, and regenerative potential. However, it is important to address a common misconception amongst the general public equating to PRP and stem cells due to the demonstrated efficacy of PRP in treating musculoskeletal and dermatological disorders. Notably, PRP promotes regeneration by providing growth factors or other paracrine factors only. Therefore, it cannot replenish or replace the lost cells in conditions where a large number of cells are required to regenerate tissues and/or organs. In such cases, cellbased therapies are the preferred option. Additionally, other tools of regenerative medicine, such as bioprinting, organoids, and mechanobiology also rely on stem cells for their success. Hence, healthcare and commercial entities offering direct-to-customer regenerative therapies should not mislead the public by claiming that the application of PRP is a stem cell-based therapy. Furthermore, it is important for regulatory bodies to strictly monitor these profit-driven entities to prevent them from providing unregulated regenerative treatments and services that claim a broad variety of benefits with little proof of efficacy, safety concerns, and obscure scientific justification.

Effectiveness of gonarthrosis treatment via intra-articular injections of linear vs. cross-linked hyaluronic acids

OBJECTIVES

The study aimed to compare the outcomes of single-dose cross-linked hyaluronic acid and the linear regimen of three doses of HA knee injections among patients with gonarthrosis.

PATIENTS AND METHODS

This single-center, retrospective study was conducted with 60 patients (47 females, 13 males; mean age: 57.9±4.29 years; range, 50 to 65 years) with Kellgren-Lawrence Grade 2 or 3 gonarthrosis between February 2020 and February 2022. Patients were either subjected to intra-articular cross-linked hyaluronic acid (n=30) or linear hyaluronic acid (n=30) injection treatments. Comprehensive assessments of the patients were conducted prior to the injections, as well as at three and six months after injection. The two injection groups were compared regarding the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Oxford Knee Score.

RESULTS

Both injections showed a statistically significant improvement from baseline in both WOMAC and Oxford Knee Score at three and six months (p<0.001). There was no notable distinction in the alteration of WOMAC knee scores between the two injection types. However, a notable discrepancy was observed in the elevation of Oxford Knee Score among patients who received cross-linked knee injections compared to those who underwent linear hyaluronic acid knee injections, signifying a significant increase in the former group (p<0.001).

CONCLUSION

The advantage of a single-dose administration of cross-linked HA knee injections, as opposed to the three-dose regimen required for linear hyaluronic acid, translates into reduced time and cost for the injection process. Moreover, this approach minimizes injection-associated discomfort for patients due to the singular dose administration.

Global trends and hotspots in the application of platelet-rich plasma in knee osteoarthritis: A bibliometric analysis from 2008 to 2022

Platelet-rich plasma (PRP) injection therapy holds great promise in improving knee cartilage repair. This bibliometric analysis aimed to explore the research landscape in the application of PRP for knee osteoarthritis (KOA) over the last 15 years. All articles investigating PRP in the application of KOA were retrieved from the web of science core collection. Publications were analyzed using R software, VOS Viewer, CiteSpace, Microsoft Excel, and an online bibliometric platform (https://bibliometric.com/). A total of 815 articles were identified, 6 articles from 2010 had the highest average number of citations in the local database. Filardo G., Kon E., Cole B.J., Marcacci M., and Di Martino A. are the top 5 authors based on the H-index. The "American Journal Of Sports Medicine" is the most authoritative journal in the field of PRP application in KOA. The United States is the global leader in this field, with European countries playing a pivotal role in collaborative exchanges. Taipei Medical University is the most prolific institution and Shahid Beheshti University Medical Sciences in Iran the fastest-rising institution. The keywords "Hyaluronic Acid," "cartilage," "growth factors," "mesenchymal stem cells," "intra-articular injection," "pain," "inflammation," "double-blind," "management," "placebo," "stromal cells," "rheumatoid arthritis," and "pathology" appeared most frequently. "Exercise," "volume," and "physical-activity" are the latest hot topics. Future trends in this field include the standardization of injection components, injection sites, and injection methods, the modulation of useful or harmful growth factor receptor expression, sports management, and the validation of contraindications to PRP.

Efficacy and safety of platelet-rich plasma combined with Tai Chi for knee osteoarthritis: study protocol for a placebo-controlled randomized trial

BACKGROUND

No definitive treatment methods of curative for knee osteoarthritis (KOA). The combined therapies that into account both the biochemical and biomechanical may provide potential opportunities for treat KOA, and previous studies have demonstrated that the platelet-rich plasma of intra-articular injection (IAI-PRP) and exercise treatments afford more benefits than do their corresponding monotherapies. The absence of a specific exercise plan and detailed explanation renders the aforementioned study results questionable. Furthermore, Tai Chi (TC) with moderate-intensity, whole body movements and good adherence may prove to be more effective for treating KOA. However, few studies examined the effectiveness and safety of combined IAI-PRP and TC for KOA.

METHODS

This study protocol will be a placebo-controlled, assessor-blinded randomized trial involving 12-week intervention and 1-year follow-up. The stratified randomization will be used to randomly assign the 212 participants to four groups: group A (placebo IAI); group B (PRP IAI); group C (TC and placebo IAI); group D (TC and PRP IAI). Injection will be performed once a week, three consecutive times as a course, after a week of rest to continue the next course, a total of 3 courses (12 week). Additionally, the TC interventions will be carried out 3 days per week for a total of 12 weeks. The primary outcome measures will include the efficacy (Western Ontario and McMaster Universities Osteoarthritis Index), acceptability and safety of these interventions. The secondary outcome measures will include physical function (Timed Up and Go test), walking function (Gait Analysis), inflammatory factor levels (e.g., Interleukin-1 β, interleukin-6, vascular endothelial growth factor), quality of life (36-Item Short Form Health Survey), volume of patellofemoral cartilage and effusion-synovitis (MRI). Two-way of variance with repeated measures will be applied to examine the main effects of the group and the time factor and group-time interaction effects for all outcome measures.

DISCUSSION

This trial will be first one to propose an integrated scheme combing IAI-PRP and TC for treatment of KOA, based on the consideration of the biochemical and biomechanical pathogenesis of KOA. These results of the study will provide evidence with high quality for integrated IAI-PRP and TC to treatment KOA. Trial Registration Chinese Clinical Trial Registry ChiCTR2300067559. Registered on 11 January 2023.

A bibliometric analysis of intra-articular injection therapy for knee osteoarthritis from 2012 to 2022

Knee osteoarthritis (KOA) is the most common joint disease worldwide and, with the progression of an aging population, is one of the most important causes of disability worldwide. Its main symptoms include articular cartilage damage, periarticular pain, swelling, and stiffness. Intra-articular (IA) injections offer many advantages over systemic administration and surgical treatment, including direct action on the target joint to improve local bioavailability, reduce systemic toxicity, and lower costs. This study analyzed KOA intra-articular injection treatment and its hot literature and research horizons using bibliometric methodologies and graphical tools to aid future research. We performed a bibliometric analysis of 2360 publications in the Web of Science core collection using CiteSpace software. The United States (28.26% of publications) and China (18%) had the biggest publications. Rush University was the most active institution, but Boston University had the greatest citation/publication rate (65.77), suggesting a high literature standard. The majority of publications were in Osteoarthritis and cartilage. Bannuru RR was the most referenced author, while Filardo, Giuseppe was the most productive author. Studies in platelet-rich plasma (PRP), mesenchymal stem cells (MSCs), and microsphere formulation are likely to be future research hotspots. The current scientometric study provides an overview of KOA intra-articular injection therapy studies from 2012 to 2022. This study outlines the current research hotspots and potential future research hotspots in the field of intra-articular injection treatment for KOA and may serve as a resource for researchers interested in this topic.

Platelet-Rich Plasma (PRP) and Adipose-Derived Stem Cell (ADSC) Therapy in the Treatment of Genital Lichen Sclerosus: A Comprehensive Review

Lichen sclerosus (LS) is a chronic inflammatory dermatosis mostly localized in the genital area, characterized by vulvar alterations that can severely impact a patient's quality of life. Current treatment modalities often provide incomplete relief, and there is a need for innovative approaches to manage this condition effectively. Platelet-rich plasma (PRP) and adipose-derived stem cells (ADSCs) have emerged as potential regenerative therapies for LS, offering promising results in clinical practice. This comprehensive review explores the utilization of PRP and ADSC therapy in the treatment of genital LS, highlighting their mechanisms of action, safety profiles, and clinical outcomes. PRP is a blood product enriched in growth factors and cytokines, which promotes tissue regeneration, angiogenesis, and immune modulation. ADSC regenerative potential relies not only in their plasticity but also in the secretion of trophic factors, and modulation of the local immune response. Numerous studies have reported the safety of PRP and ADSC therapy for genital LS. Adverse events are minimal and typically involve mild, self-limiting symptoms, such as transient pain and swelling at the injection site. Long-term safety data are encouraging, with no significant concerns identified in the literature. PRP and ADSC therapy have demonstrated significant improvements in LS-related symptoms, including itching, burning, dyspareunia, and sexual function. Additionally, these therapies enable many patients to discontinue the routine use of topical corticosteroids. Several studies have explored the efficacy of combining PRP and ADSC therapy for LS. In combination, PRP and ADSCs seem to offer a synergistic approach to address the complex pathophysiology of LS, particularly in the early stages. The use of PRP and ADSC therapy for genital lichen sclerosus represents a promising and safe treatment modality. These regenerative approaches have shown significant improvements in LS-related symptoms, tissue trophism, and histological features. Combination therapy, which harnesses the synergistic effects of PRP and ADSCs, is emerging as a preferred option, especially in early-stage LS cases. Further research, including randomized controlled trials and long-term follow-up, is warranted to elucidate the full potential and mechanisms of PRP and ADSC therapy in the management of genital LS. These regenerative approaches hold great promise in enhancing the quality of life of individuals suffering from this challenging condition.

Efficacy and Safety of Hyaluronic Acid and Platelet-Rich Plasma Combination Therapy Versus Platelet-Rich Plasma Alone in Treating Knee Osteoarthritis: A Systematic Review

Knee osteoarthritis (KOA) is a chronic degenerative disease of the joint characterized by biochemical and biomechanical alterations of articular cartilage, degradation of the joint edge, and subchondral bone hyperplasia. Nowadays, intra-articular hyaluronic acid (HA) or platelet-rich plasma (PRP) has become a popular treatment modality for treating KOA. Each treatment can be used independently or in combination. However, the efficacy and safety of combination treatment are still inconclusive, and there is a lack of high-quality level 1 studies that support using combination therapy over PRP alone. Consequently, we conducted a systematic review to examine the effectiveness and safety of combining HA and PRP therapy versus using PRP therapy alone in KOA patients. Based on the most up-to-date evidence, the dual approach of PRP and HA therapy yields outcomes similar to PRP therapy alone in the short term, up to 12 months. Nonetheless, when considering longer-term results, particularly in the 24-month follow-up, dual therapy holds the potential to produce superior outcomes compared to PRP alone therapy. Additionally, in terms of safety, dual therapy has been associated with slightly fewer adverse events.

Inflammatory ultrasound features as prognostic factors of pain and functional outcomes following intra-articular platelet-rich plasma in knee osteoarthritis

AIM

To explore inflammatory ultrasound predictors of improvements in pain and function over 2, 6, and 12 months following administration of intra-articular platelet-rich plasma (PRP) in knee osteoarthritis (OA).

METHOD

Patients with painful mild-moderate radiographic knee OA from a subset of the RESTORE RCT underwent ultrasound assessment according to the standardized OMERACT scanning protocol to detect inflammatory features such as synovitis, synovial hypertrophy, and effusion with power Doppler. The study knee was treated with 3 once-weekly PRP injections obtained after centrifugation at 1500 g for 5 min. Numerical Rating Score (NRS), Intermittent and Constant Osteoarthritis Pain (ICOAP) questionnaire, and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) function sub-score were used to measure pain and functional severity. Separate linear regression models were performed to determine whether baseline ultrasound-detected features of inflammation predicted the improvement in pain and function following PRP injection in both unadjusted and adjusted models for confounders.

RESULTS

Forty-four participants were included, with 25 (56.8%) being female. In an unadjusted model, higher OMERACT scores for inflammatory features such as global synovitis and/or effusion were significantly associated with greater improvement in all outcomes measured at 2 months but not at 6 and 12 months for pain measures. Only global synovitis showed significant association with functional improvement at 2 and 12 months. Similar findings were observed in the adjusted model.

CONCLUSION

Ultrasound indices of knee inflammation predicted short-term improvements in pain severity and both short- and longer-term improvements in function following intra-articular PRP injection.

Do age, gender, BMI and disease duration influence the clinical outcomes in patients of knee osteoarthritis treated with serial injections of autologous platelet rich plasma?

Purpose

To study whether age, gender, body mass index(BMI) and disease duration influence the clinical outcomes in kellgren-Lawrence(K-L) grade II,III knee osteoarthritis(KOA) patients treated with serial injections of platelet rich plasma(PRP).

Patients and methods

65 patients were given three monthly intra-articular injections of PRP in this prospective interventional study. The patients were divided into subgroups depending on the factor studied: by age(in years) into young <45(n = 7), middle age 45-60(n = 35), and elderly >60(n = 23): by BMI(in kg/m2) into; normal <25(n = 25), overweight 25-30(n = 27) and obese >30(n = 13) and disease duration; less(n = 32) or more than 1 year(n = 33) symptom duration. Visual analogue scale (VAS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) were used as outcome measures and assessed before each injection and then at 6 and 9 months post injection. Groups were homogenous with respect to baseline characteristics.

Results

Mean VAS and WOMAC scores showed a statistically significant improvement (P < 0.0001) across all groups and subgroups (age,gender,BMI,disease duration) at follow up. On intra-subgroup comparison, we found no significant differences(P > 0.05) among age, BMI or gender subgroups, however the scores were significantly better in patients with disease duration of less than 1 year than those with more than 1 year duration at both 6 and 9 months[P < 0.001(RC = 9.630,95% CI = 4.037-15.222,P = 0.001)].

Conclusion

PRP injections if given serially can improve the short term subjective scores of VAS and WOMAC scores in patients with K-L grade II and III KOA irrespective of age, gender, BMI or disease duration, however, clinical benefits can be maximized if given early in the disease course.

The Clinical Efficacy of Autologous Platelet-Rich Plasma Interventional Circulatory Perfusion Combined with Radiofrequency Ablation and Thermocoagulation in the Treatment of Discogenic Low Back Pain

Objective

In this study, we aimed to explore the efficacy of the autologous platelet-rich plasma (PRP) interventional circulatory perfusion combined with radiofrequency ablation and thermocoagulation (RFAT) in the treatment of discogenic low back pain (DLBP).

Methods

From January 2020 to November 2022, 158 patients of the Second Affiliated Hospital of Nanchang University were selected as the study subjects, and 24 patients met the exclusion criteria. The 134 patients who met the inclusion criteria were divided into 65 patients in the control group (3 patients lost to follow-up) and 69 patients in the observation group (5 patients lost to follow-up), so 126 patients were actually completed the study, including 62 patients in the control group and 64 patients in the observation group. The control group responsible disc received RFAT, and an interventional circulatory perfusion was performed; the observation group received RFAT, and an interventional circulatory perfusion was performed, and then autologous PRP 2 ml was injected. Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) were performed before and 4 and 8 weeks after treatment, and the efficacy was evaluated at 4 and 8 weeks after treatment. The changes of lumbar disc MRI before and after treatment were observed.

Results

The differences in the Visual Analog Scale (VAS) scores and the Oswestry Disability Index (ODI) between the observation group and the control group before the treatment were not statistically significant (P > 0.05 in both). However, four weeks and eight weeks after the treatment, the VAS scores and the ODIs were significantly lower in both groups than those before the treatment (P < 0.05 in both). In terms of the therapeutic efficacy, eight weeks after the treatment, the total effective rates in the control group and the observation group were 67.7% and 87.5%, respectively, with the observation group being superior to the control group (P < 0.05).

Conclusion

After RFAT, interventional circulatory perfusion combined with autologous PRP intramedullary injection in the lumbar disc is a safe and effective treatment for DLBP, and it had superior long-term effects in improving the clinical symptoms and patient dysfunction than the RFAT and interventional circulatory perfusion.

Efficacy and safety of platelet-rich plasma injections for the treatment of osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

Background

In recent years, platelet-rich plasma (PRP) injections for osteoarthritis (OA) have been widely promoted in clinical practice, but their effectiveness is controversial. Therefore, we conducted a meta-analysis of relevant randomized controlled trials (RCTs) to determine the efficacy and safety of PRP injections for the treatment of OA.

Methods

We searched databases including Embase, Web of Science, Medline, PubMed, and the Cochrane Library for relevant studies. Two researchers (YQX and CG) performed literature screening, baseline data extraction, literature quality assessment, and heterogeneity analysis of RCTs from the retrieved studies. Based on the magnitude of heterogeneity I², random-effects or fixed-effects models were selected for the meta-analysis.

Results

We included 24 RCTs comprising 1344 patients with OA who met the inclusion criteria, with the main types of morbidity being knee osteoarthritis (KOA), hip osteoarthritis (HOA), ankle osteoarthritis (AOA), and temporomandibular joint osteoarthritis (TMJOA). Our results indicate that PRP injections were effective in improving Visual Analog Scale (VAS) pain scores in patients with KOA, HOA, and AOA compared to controls (AOA, MD = -1.15, CI = 95% [-1.74, -0.56], I² = 40%, P < 0.05; KOA, MD = -1.03, CI = 95% [-1.16, -0.9], I² = 87%, P < 0.05; TMJOA, MD = -1.35, CI = 95% [-1.74, -0.97], I² = 92%, P < 0.05) but showed no significant efficacy in patients with HOA (MD = -0.27, CI = 95% [-0.8, 0.26], I² = 56%, P>0.05). Compared to controls, PRP injections were effective in improving Knee Injury and Osteoarthritis Outcome Score (KOOS), including the patient's pain symptoms, activities of daily living (ADL), and adhesion symptomatology, but not for that of sports function (KOOS-pain, MD = 2.77, CI = 95% [0, 5.53], I² = 0%, P < 0.05; KOOS-symptoms, MD = 3.73, CI = 95% [0.76, 6.71], I² = 0%, P < 0.05; KOOS-ADL, MD = 3.61, CI = 95% [0.79, 6.43], I² = 0%, P < 0.05; KOOS-QOL, MD = 4.66, CI = 95% [0.98, 8.35], I² = 29%, P < 0.05, KOOS-sport, MD = 0.48, CI = 95% [-3.02, 3.98], I² = 0%, P > 0.05). PRP injections were effective in improving Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores, including pain, stiffness, and functional joint motion, in patients with OA compared with the control group (WOMAC-pain, MD = -1.08, CI = 95% [-1.62, -0.53], I² = 87%, P < 0.05; WOMAC-stiffness, MD = -1.17, CI = 88% [-1.72, -0.63], I² = 87%, P < 0.05; WOMAC-function, MD = -1.12, CI = 95% [-1.65, -0.58], I² = 87%, P < 0.05). In addition, subgroup analysis showed that leukocyte-poor (LP) PRP injections were more effective than leukocyte-rich (LR) PRP injections in improving pain symptoms in patients with OA (VAS, LR-PRP, MD = -0.81, CI = 95% [-1.65, -0.03], I² = 83%, P = 0.06 > 0.05; LP-PRP, MD = -1.62, CI = 95% [-2.36, -0.88], I² = 92%, P < 0.05). A subgroup analysis based on injection sites showed that no statistical difference in efficacy between intra-articular (IA) combined with intra-osseous (IO) simultaneous PRP injections. IA PRP injections only improved VAS pain scores in patients with OA (IA+IO PRP injections, MD = -0.74, CI =95% [-1.29, -0.18], I² = 61%, P < 0.05; IA PRP injections, MD = -1.43, CI = 95% [-2.18, -0.68], I² = 87%, P < 0.05, test for subgroup differences, P > 0.05, I² = 52.7%).

Conclusion

PRP injection therapy can safely and effectively improve functional activity in patients with OA and produce positive analgesic effects in patients with KOA, TMJOA, and AOA. However, PRP injection therapy did not significantly reduce pain symptoms in patients with HOA. In addition, the analgesic effect of LP-PRP was greater than that of LR-PRP.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022362066.

Regenerative methods in osteoarthritis

Osteoarthritis (OA) is the most common type of arthritis that can affect all joint structures. The primary goals of osteoarthritis treatment are to alleviate pain, reduce functional limitations, and improve quality of life. Despite its high prevalence, treatment options for osteoarthritis are limited, with most therapeutic approaches focusing on symptom management. Tissue engineering and regenerative strategies based on biomaterials, cells, and other bioactive molecules have emerged as viable options for osteoarthritis cartilage repair. Platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) are the most commonly used regenerative therapies today to protect, restore, or increase the function of damaged tissues. Despite promising results, there is conflicting evidence regarding the efficacy of regenerative therapies, and their efficacy remains unknown. The data suggest that more research and standardization are required for the use of these therapies in osteoarthritis. This article provides an overview of the application of MSCs and PRP applications.

A Review of Recent Innovations in Cartilage Regeneration Strategies for the Treatment of Primary Osteoarthritis of the Knee: Intra-articular Injections

Background

The pathology of primary osteoarthritis (OA) begins with structural cartilage damage, which initiates a self-propagating inflammatory pathway that further exacerbates cartilage deterioration. Current standard of care for knee primary OA involves treating the inflammatory symptoms to manage pain, which includes intra-articular (IA) injections of cortisone, an anti-inflammatory steroid, followed by a series of joint-cushioning hyaluronic acid gel injections. However, these injections do not delay the progression of primary OA. More focus on the underlying cellular pathology of OA has prompted researchers to develop treatments targeting the biochemical mechanisms of cartilage degradation.

Purpose

Researchers have yet to develop a United States Food and Drug Administration (FDA)-approved injection that has been demonstrated to significantly regenerate damaged articular cartilage. This paper reviews the current research on experimental injections aimed at achieving cellular restoration of the hyaline cartilage tissue of the knee joint.

Study Design

Narrative review.

Methods

The authors conducted a narrative literature review examining studies on primary OA pathogenesis and a systematic review of non-FDA-approved IA injections for the treatment of primary OA of the knee, described as "disease-modifying osteoarthritis drugs" in phase 1, 2, and 3 clinical trials.

Conclusion

New treatment approaches for primary OA investigate the potential of genetic therapies to restore native cartilage. It is clear that the most promising IA injections that could improve treatment of primary OA are bioengineered advanced-delivery steroid-hydrogel preparations, ex vivo expanded allogeneic stem cell injections, genetically engineered chondrocyte injections, recombinant fibroblast growth factor therapy, injections of selective proteinase inhibitors, senolytic therapy via injections, injectable antioxidant therapies, injections of Wnt pathway inhibitors, injections of nuclear factor-kappa β inhibitors, injections of modified human angiopoietin-like-3, various potential viral vector-based genetic therapy approaches, and RNA genetic technology administered via injections.

Comparisons of Cytokines, Growth Factors and Clinical Efficacy between Platelet-Rich Plasma and Autologous Conditioned Serum for Knee Osteoarthritis Management

This study aimed to directly compare the contents and the clinical efficacy of the two autologous blood-derived products, platelet-rich plasma (PRP) and autologous conditioned serum (ACS) for osteoarthritis (OA) treatment. The contents of standard-prepared PRP and ACS prepared at 37 °C for 1 h, 3 h, 6 h, and 24 h from healthy volunteers were compared. The clinical efficacy of pain relief in patients with Stage III knee OA was evaluated by a patient-reported visual analog scale (VAS) pain rating. PDGF-BB levels in ACS 1 h were significantly higher than those in PRP, and the levels in ACS preparations remained stable. IGF-1 level of ACS 24 h showed a significant increase compared to those of other ACS preparations and PRP. ACS 3 h showed a turning of IL-1Ra level and revealed a time-dependent increase up to 24 h. ACS 6 h showed a turning increase in TNF-α levels. ACS 3 h was chosen for clinical comparison with PRP. The reduction in pain VAS in the ACS group was significantly more compared to those of the PRP group (p = 0.028). However, PRP showed significant earlier improvement (p < 0.001). Conclusion: ACS contained higher levels of PDGF-BB and IL-1Ra and provided better improvement in pain relief compared to PRP.

Effect of platelet-rich plasma versus steroid injection in plantar fasciitis: a randomized clinical trial

BACKGROUND

Plantar fasciitis (PF) is a common orthopaedic problem, with heel pain worsening the quality of life. Although steroid injection is often used if the conservative treatment fails, Platelet-Rich Plasma (PRP) injection is gaining popularity due to its safety and long-lasting effect. However, the effect of PRP versus steroid injection in PF has not been studied yet in Nepal. Therefore, this study aimed to assess the effect of PRP compared with steroid injection in the treatment of PF.

METHODS

This study was a single-center, hospital-based, open-label, parallel-group randomized clinical trial to compare the effect of PRP injection with steroid injection in plantar fasciitis between August 2020 and March 2022. A total of 90 randomly selected participants aged 18 to 60 years suffering from plantar fasciitis with failed conservative treatment were intervened. The American Orthopaedic Foot and Ankle Society (AOFAS) and the Visual Analog Scale (VAS) scoring system were used to evaluate functional mobility and pain before and after the intervention for three and six months, respectively. Statistical analyses were performed using a Student's two-sample t-test. P-value < 0.05 was considered statistically significant.

RESULTS

The PRP injection showed a better outcome than the steroid injection in six months follow-up. The mean (± SD) VAS score was significantly decreased in the PRP group (1.97 + 1.13) than in the steroid group (2.71 ± 0.94) with the group difference of -0.73 (95% CI: -1.18 to -0.28) at six months. Similarly, there was a significant increase in the AOFAS scores in the PRP group (86.04 ± 7.45) compared to the steroid group (81.23 ± 9.60) at six months of follow-up with a group difference of 4.80 (95% CI: 1.15 to 8.45). There was also a significant reduction of plantar fascia thickness in the PRP group compared to that of the steroid group (3.53 ± 0.81 versus 4.58 ± 1.02) at six months of follow-up with the group difference of -1.04 (95% CI: -1.44 to -0.65).

CONCLUSION

The PRP injection showed better outcomes than steroid injection in plantar fasciitis treatment over the course of six months. Further research with a larger population and longer follow-up than six months is needed to generalize the findings and their long-term efficacy.

TRIAL REGISTRATION

NCT04985396. First registered on 02 August 2021. ( https://clinicaltrials.gov/ct2/show/NCT04985396 ).

Serial intraarticular injections of growth factor concentrate in knee osteoarthritis: A placebo controlled randomized study

Objective

To evaluate and compare clinical efficacy and effect on specific serum biomarker with serial injections of growth factor concentrate (GFC) for knee osteoarthritis (KOA) in a randomized triple blinded placebo controlled interventional study.

Methods

Final assessment was done on 58 patients. Patients with Kellgren-Lawrence grade II, III knee osteoarthritis were administered monthly intraarticular injections(3 injections) of GFC(n = 31) or saline(n = 27) and evaluated clinically with visual analogue scale(VAS) and Western Ontario and McMaster Universities Arthritis Index(WOMAC) at 3,6 and 12 months post therapy. Biochemical analysis was done with serum biomarker of cartilage degeneration, Collagen 2-1 (Coll2-1), estimated at baseline and at final follow up.

Results

Both the groups exhibited statistically significant improvements (P < 0.05) in VAS at 3,6 and 12 months. WOMAC improvement reached statistical significance for GFC group at every evaluation (P < 0.001) but only at 12 months in NS group (P = 0.029). The improvements were clinically meaningful only in GFC group throughout follow up (Minimal clinically important differences >12% of baseline in WOMAC and >2 cm difference in mean for VAS). Intergroup comparison revealed GFC to be much better for both scores at every evaluation (95% CI of 0.2-1.5,[P = 0.008], 1.4-2.9,[P < 0.0001], and 2.7-4.2,[P < 0.0001] for VAS, 7.3-16.0 [P < 0.001], 11.6-21.9 [P < 0.001] and 18.1-31.1[P < 0.001] for WOMAC). Statistically significant decrease in serum Coll2-1 levels were observed for GFC group only. No serious complications were seen.

Conclusion

Serial(three) monthly GFC injections result in clinically meaningful improvement of subjective pain and function outcome scores, sustaining up to 12 months in KOA grade II and III. GFC also lead to significant reduction in serum levels of cartilage degradation biomarker coll2-1.

Intra-articular platelet-rich plasma vs. corticosteroid injections efficacy in knee osteoarthritis treatment: a systematic review

Osteoarthritis (OA) affects the entire joint structure. The most injured joints are the hands, knees, and hips. OA is a common disease all over the world, and a cause of disability in the elderly; hence, medicine is facing a steady challenge to find effective therapeutics to relieve the pain, improving symptoms for a better quality of life for patients.

Purpose

To compare the results, in the recent literature, of intra-articular injection of platelet-rich plasma (PRP) and corticosteroids (CSs) in osteoarthritic knees at early and mid-term postinjection.

Methods

A PubMed and CENTRAL (Cochrane Central Register of Controlled Trials) database search was performed. Initial screening yielded 108 randomized controlled trials, 17 results, and 17 others were added after updates. The final review includes nine randomized control trials, with outcome evaluating of knee OA by Western Ontario and McMaster Universities Arthritis Osteoarthritis Index, Knee Injury and Osteoarthritis Outcome Scale Index, and Visual Analog Scale.

Results

PRP and CS intra-articular injections both are safe and effective treatments in knee OA for alleviating pain, and improving symptoms. It seems that PRP injections have prolonged and shown better improvement in some studies. However, the results do not prefer one method over the other.

Conclusion

Up till now, it is not easy to draw firm conclusions about prioritizing PRP or CS injections for knee OA treatment due to the limitation of this review.

Platelet-rich plasma attenuates the severity of joint capsule fibrosis following post-traumatic joint contracture in rats

Background: Post-traumatic joint contracture (PTJC) mainly manifests as excessive inflammation leading to joint capsule fibrosis. Transforming growth factor (TGF)-β1, a key regulator of inflammation and fibrosis, can promote fibroblast activation, proliferation, migration, and differentiation into myofibroblasts. Platelet-rich plasma (PRP) is considered to have strong potential for improving tissue healing and regeneration, the ability to treat joint capsule fibrosis remains largely unknown. Methods: In this study, we aimed to determine the antifibrotic potential of PRP in vivo or in vitro and its possible molecular mechanisms. The TGF-β1-induced primary joint capsule fibroblast model and rat PTJC model were used to observe several fibrotic markers (TGF-β1, α-SMA, COL-Ⅰ, MMP-9) and signaling transduction pathway (Smad2/3) using histological staining, qRT-PCR and western blot. Results: Fibroblasts transformed to myofibroblasts after TGF-β1 stimulation with an increase of TGF-β1, α-SMA, COL-Ⅰ, MMP-9 and the activation of Smad2/3 in vitro. However, TGF-β1-induced upregulation or activation of these fibrotic markers or signaling could be effectively suppressed by the introduction of PRP. Fibrotic markers' similar changes were observed in the rat PTJC model and PRP effectively reduced inflammatory cell infiltration and collagen fiber deposition in the posterior joint capsule. Interestingly, HE staining showed that articular cartilage was degraded after rat PTJC, and PRP injection also have the potential to protect articular cartilage. Conclusion: PRP can attenuate pathological changes of joint capsule fibrosis during PTJC, which may be implemented by inhibiting TGF-β1/Smad2/3 signaling and downstream fibrotic marker expression in joint capsule fibroblasts.

Application of platelet-rich plasma in spinal surgery

With the aging of the population and changes in lifestyle, the incidence of spine-related diseases is increasing, which has become a major global public health problem; this results in a huge economic burden on the family and society. Spinal diseases and complications can lead to loss of motor, sensory, and autonomic functions. Therefore, it is necessary to identify effective treatment strategies. Currently, the treatment of spine-related diseases includes conservative, surgical, and minimally invasive interventional therapies. However, these treatment methods have several drawbacks such as drug tolerance and dependence, adjacent spondylosis, secondary surgery, infection, nerve injury, dural rupture, nonunion, and pseudoarthrosis. Further, it is more challenging to promote the regeneration of the interstitial disc and restore its biomechanical properties. Therefore, clinicians urgently need to identify methods that can limit disease progression or cure diseases at the etiological level. Platelet-rich plasma (PRP), a platelet-rich form of plasma extracted from venous blood, is a blood-derived product. Alpha granules contain a large number of cytokines, such as platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), epidermal growth factor, platelet factor 4 (PF-4), insulin-like growth factor-1 (IGF-1), and transforming growth factor-β (TGF-β). These growth factors allow stem cell proliferation and angiogenesis, promote bone regeneration, improve the local microenvironment, and enhance tissue regeneration capacity and functional recovery. This review describes the application of PRP in the treatment of spine-related diseases and discusses the clinical application of PRP in spinal surgery.

An Open-Labeled Randomized Prospective Multi-center Study to Evaluate the Efficacy and Safety of Intra-articular Injection of OSSINEXT™, an Autologous Growth Factor Concentrate (AGFC) Compared to Hyaluronic Acid (HA) in Knee Osteoarthritis

BACKGROUND

Osteoarthritis (OA) is known as degenerative arthritis and is the second most common rheumatologic problem with a prevalence of 22%-39% in India. Knee OA (KOA) is a major cause of mobility impairment, particularly among females. Non-surgical treatment options for KOA include intra-articular injections of platelet-rich plasma (PRP) and hyaluronic acid (HA). Most commercially available PRP preparation kits do not remove RBCs and WBCs which are detrimental to the healing effects. Wockhardt Regenerative Pvt. Ltd., Mumbai, India has developed a kit known as Ossinext™ which has an advantage over traditional PRP in that it eliminates RBCs and WBCs. This study was conducted to evaluate the effectiveness and safety of intra-articular injection of Wockhardt's Ossinext™ an autologous growth factor concentrate (AGFC) versus HA in KOA.

METHODS

 Male and female patients in the age group between 30 and 75 years with confirmed KOA on radiological assessment with Grades I-III on the Kellgren-Lawrence Grading Scale and with visual analog scale (VAS) pain score of 4 or more (on the numeric rating scale) in spite of taking non-steroidal anti-inflammatory drugs (NSAIDs) since past 2 weeks were considered for study participation. This was an open-labeled study and eligible patients were randomly allocated to AGFC or HA in a 1:1 fashion. Three intra-articular injections were given in the affected knee joint, i.e. at baseline, month 1, and month 2 visits. Patients were evaluated at regular intervals, i.e. at months 5, 8, and 11 for primary and secondary endpoints. The primary efficacy endpoint for this study was change from baseline in WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) scores at month 11 whereas the secondary efficacy endpoints were change from baseline of VAS pain scale at months 1, 2, 5, 8, and 11 as well as change from baseline of WOMAC, KOOS (Knee and Osteoarthritis Outcome System), and IKDC (International Knee Documentation Committee) scale at month 5, 8, and 11. For analysis a mixed model for repeated measures was used.

RESULTS

 Out of the 100 patients who were enrolled, 50 patients each were randomized to AGFC and HA arm. The results were analyzed from 99 patients (49 for AGFC and 50 for HA) who met the criteria for the modified intent to treat (mITT) population. At month 11 on the WOMAC scale, there was greater improvement seen with Ossinext™ compared to HA group which was also statistically significant with p-value of 0.0332. Within the group, there was statistically significant improvement before and after treatment in all scales, i.e. WOMAC, KOOS, IKDC, and VAS at all time points, i.e. months 5, 8, and 11 with a p-value as low as <0.0001. Within the group, the VAS score showed statistically significant improvement even at months 1 and 2 as well. A total of 24 patients reported 37 adverse events (AEs) during the study, most common being pain, pyrexia and swelling but none of the AEs reported during the study were considered as severe in intensity. There were no safety concerns reported.

CONCLUSIONS

In conclusion, greater and statistically significant improvement was seen with Ossinext™ in WOMAC scores at month 11 compared to HA. Ossinext™ also showed marked statistically significant improvement from before treatment to after treatment in the WOMAC, KOOS, IKDC, and VAS scales used for the assessment of KOA with a p-value as low as <0.0001. Ossinext™ was also safe and well-tolerated.

Serial Platelet-Rich Plasma Intra-articular Injections in Kellgren and Lawrence Grade IV Knee Joint Osteoarthritis: A Prospective Blinded Placebo-Controlled Interventional Study

Purpose

The purpose of this study was to evaluate whether serial intra-articular (IA) Platelet-Rich Plasma (PRP) injections improve pain and function in patients of Kellgren-Lawrence (K-L) Grade IV primary knee osteoarthritis (KOA), not willing for arthroplasty or having relative contraindications to surgery.

Methods

90 patients (84 available at final follow-up) of Grade IV KOA were given 3 PRP or Normal Saline injections at 1-month interval. Pain and functional assessment was done with Visual analog scale (VAS) and Western Ontario and McMaster universities osteoarthritis index (WOMAC) respectively, at baseline and then at three and six months of follow-up. Both groups were homogenous with similar baseline characteristics.

Results

Both groups showed statistically significant improvements in the outcome scores but only PRP showed minimal clinically important difference (25% in WOMAC and > 2 cm difference of mean in VAS at follow-up). For inter-group comparison, PRP showed better results as there was statistically significant difference in WOMAC at 3 months (Difference =  - 9.220, 95% CI =  - 13.1945 to - 5.2455, P < 0.0001) and at 6 months (Difference =  - 10.360, 95% CI =  - 14.5358 to - 6.1842, P < 0.0001). Similar results were seen for VAS also (Difference =  - 0.580, 95% CI =  - 1.1412 to - 0.0188, P = 0.04 at 3 months, Difference =  - 0.870, 95% CI - 1.3993 to - 0.3407, P = 0.001 at 6 months). Outcome scores significantly correlated with age and sex but not with body mass index (BMI).

Conclusion

Serial Intra-articular Injections of autologous PRP mildly improve short-term subjective pain and knee function scores in patients of Grade IV KOA without any major complications.

Effects of local anesthetics and contrast agents on musculoskeletal regenerative medicine procedures

In regenerative medicine, cells, tissues and organs are often replaced, engineered or regrown in order to restore their function after they have been damaged or lost. Local anesthetics, corticosteroids and contrast agents are commonly employed for both diagnostic and therapeutic objectives in interventional pain and musculoskeletal treatments for regenerative medicine. There is growing evidence that routine injectables promote catabolism and disease processes. Thus, understanding the effects of these compounds on regenerative medicine injectates and target tissues such as tenocytes, chondrocytes, nucleus pulposus and ligamentous tissue is critical. This review includes the current research on the effects of local anesthetics and contrast agents, as well as their use and recommendations in regenerative medicine operations.

Relative Efficacy of Intra-articular Injections in the Treatment of Knee Osteoarthritis: A Systematic Review and Network Meta-analysis

BACKGROUND

In younger patients and those without severe degenerative changes, the efficacy of intra-articular (IA) injections as a nonoperative modality for treating symptomatic knee osteoarthritis (OA)-related pain while maintaining function has become a subject of increasing interest.

PURPOSE

To assess and compare the efficacy of different IA injections used for the treatment of knee OA, including hyaluronic acid (HA), corticosteroids (CS), platelet-rich plasma (PRP), and plasma rich in growth factors (PRGF), with a minimum 6-month patient follow-up.

STUDY DESIGN

Meta-analysis of randomized controlled trials; Level of evidence, 1.

METHODS

A systematic review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using the following databases: PubMed/MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Google Scholar. Mean or mean change from baseline and standard deviation for outcome scores regarding pain and function were recorded at the 6-month follow-up and converted to either a 0 to 100 visual analog scale score for pain or a 0 to 100 Western Ontario and McMaster Universities Osteoarthritis Index score for function. A frequentist network meta-analysis model was developed to compare the effects of HA, CS, PRP, PRGF, and placebo on patient-reported outcomes.

RESULTS

All IA treatments except CS were found to result in a statistically significant improvement in outcomes when compared with placebo. PRP demonstrated a clinically meaningful difference in function-related improvement when compared with CS and placebo due to large effect sizes. Studies evaluating outcomes of PRGF reported significant improvement when compared with placebo due to large effect sizes, whereas a potential clinically significant difference was detected in the same comparison parameters in pain evaluation. With regard to improvements in pain, function, and both combined, PRP was found to possess the highest probability of efficacy, followed by PRGF, HA, CS, and placebo.

CONCLUSION

PRP yielded improved outcomes when compared with PRGF, HA, CS, and placebo for the treatment of symptomatic knee OA at a minimum 6-month follow-up. Further investigations evaluating different IA and other nonoperative treatment options for patients with knee OA are warranted to better understand the true clinical efficacy and long-term outcomes of nonsurgical OA management.

Platelet-Rich Plasma Versus Microfragmented Adipose Tissue for Knee Osteoarthritis: A Randomized Controlled Trial

Background:

Platelet-rich plasma (PRP) has been established as safe and effective for knee osteoarthritis (OA). Another orthobiologic therapy, microfragmented adipose tissue (MFAT), has gained attention because of its heterogeneous cell population (including mesenchymal stem cells). However, prospective comparative data on MFAT are lacking. Because of the safety, efficacy, and simplicity of PRP, new therapeutics such as MFAT should be compared directly with PRP.

Purpose:

To compare patient-reported outcomes of a single injection of PRP versus MFAT for knee OA.

Study Design:

Randomized controlled trial; Level of evidence, 2.

Methods:

A total of 58 patients with symptomatic knee OA (Kellgren-Lawrence grades 1-4) were randomized to receive a single injection of either leukocyte-rich PRP or MFAT under ultrasound guidance. PRP was created by processing 156 mL of whole blood. MFAT was created by harvesting 30 mL of adipose tissue via standard lipoaspiration. Scores for the Knee injury and Osteoarthritis Outcome Score (KOOS) subscales and visual analog scale for pain with Activities of Daily Living (VAS-ADL) were recorded at baseline and at 1, 3, and 6 months after the injection. The primary outcome was the KOOS–Pain subscore at 6 months after the injection.

Results:

The PRP group (n = 30) had a mean volume of 5.12 ± 1.12 mL injected. This consisted of a mean platelet count of 2673.72 ± 1139.04 × 10³/µL and mean leukocyte count of 25.36 ± 13.27 × 10³/µL (67.81% lymphocytes, 18.66% monocytes, and 12.33% neutrophils). The MFAT group (n = 28) had a mean volume of 7.92 ± 3.87 mL injected. The mean total nucleated cell count was 3.56 ± 4.62 million/mL. In both groups, KOOS subscale and VAS-ADL scores improved from baseline, and there was no significant difference between the PRP and MFAT groups in the final KOOS–Pain subscore (80.38 ± 16.07 vs 81.61 ± 16.37, respectively; P = .67) or any other outcome score.

Conclusion:

A single injection of either PRP or MFAT resulted in a clinically meaningful improvement for patients with knee OA at 6 months, with no difference between treatment groups.

Registration:

NCT04351087 (ClinicalTrials.gov identifier).

Mesenchymal Stem Cell Studies in the Goat Model for Biomedical Research—A Review of the Scientific Literature

Simple Summary

This review article aims to compile the works published in the scientific literature, over the last two decades, that use the goat as an animal model in preclinical studies using stem cells, alone or associated with biomaterials, for the treatment of injury or disease in divers organ systems. These preclinical studies are performed prior to human clinical trials for the implementation of new medical or surgical therapies in clinical practice. Thus, it appears that, in the area of tissue engineering and regenerative medicine, the caprine model is particularly used in studies using stem cells in the musculoskeletal system but, although in a more limited way, also in the field of dermatology, ophthalmology, dentistry, pneumology, cardiology, and urology. It appears that the goat represents a particularly useful animal model for studies related to the locomotor system because of its size, and also because they have a more active behavior than sheep, being more similar to the human species in this aspect. Additionally, the goat knee anatomy and the thickness of the cartilage that covers this joint are closer to that of humans than that of other large animal models commonly used in orthopedic research.

Abstract

Mesenchymal stem cells (MSCs) are multipotent cells, defined by their ability to self-renew, while maintaining the capacity to differentiate into different cellular lineages, presumably from their own germinal layer. MSCs therapy is based on its anti-inflammatory, immunomodulatory, and regenerative potential. Firstly, they can differentiate into the target cell type, allowing them to regenerate the damaged area. Secondly, they have a great immunomodulatory capacity through paracrine effects (by secreting several cytokines and growth factors to adjacent cells) and by cell-to-cell contact, leading to vascularization, cellular proliferation in wounded tissues, and reducing inflammation. Currently, MSCs are being widely investigated for numerous tissue engineering and regenerative medicine applications. Appropriate animal models are crucial for the development and evaluation of regenerative medicine-based treatments and eventual treatments for debilitating diseases with the hope of application in upcoming human clinical trials. Here, we summarize the latest research focused on studying the biological and therapeutic potential of MSCs in the goat model, namely in the fields of orthopedics, dermatology, ophthalmology, dentistry, pneumology, cardiology, and urology fields.

The use of platelet-rich plasma in management of musculoskeletal pain: a narrative review

Musculoskeletal pain is the most common pain reported by patients. Platelet-rich plasma (PRP) is widely used to treat musculoskeletal pain. However, the efficacy of PRP to treat this pain remains controversial. This review highlights the application of PRP in the treatment of musculoskeletal pain. PRP treatment appears to reduce pain and improve function in patients with musculoskeletal pain. However, there are limitations to the currently published studies. These limitations include the PRP preparation methods, type of activators, types of pathology to be treated, methods and times of administration, and association of PRP with other treatments.

Repeated Intra-Articular Administration of Platelet-Rich Plasma (PRP) in Temporomandibular Disorders: A Clinical Case Series

Background: Temporomandibular joint disorders (TMDs) are manifested, inter alia, by pain and limited scope of the mandibular abduction. Among the treatment strategies for these ailments, intra-articular injections of autologous blood preparations, including platelet-rich plasma (PRP), are administered. This prospective case series was aimed at assessing the effectiveness of repeated platelet-rich plasma (PRP) administration to the TMJ cavities in terms of reducing articular pain and increasing the mobility of the mandible. Material and methods: 40 consecutive patients diagnosed with TMJ pain qualified for the case series. The entire treatment program consisted of five PRP administrations and a summary appointment. Regression was analyzed for (1) intensity of spontaneous pain; (2) effectiveness of spontaneous pain relief; (3) mastication efficiency values; (4) painless mandibular abduction; (5) maximum mouth opening. The correlations between the abovementioned variable series were analyzed. Results: The mean spontaneous pain decreased consistently with successive PRP administrations in line with the regression model: −0.4x + 4.2 (R2 = 0.98). Articular pain improvement was reported in 71% of joints treated. Improvement in chewing quality at the end of the entire injection cycle was found in 63% of patients. The equations for the linear regression models for painless mandibular abduction (five applications of PRP) and maximum mouth opening (the first four applications of PRP) were x + 34 (R2 = 0.89) and 0.6x + 43.6 (R2 = 0.96), respectively. Improvement in these domains was found in 78% and 53% of patients, respectively. The strongest correlations were found between pain and chewing efficiency (−0.95), pain and painless mandible abduction (−0.96), and painless mandibular abduction and mastication efficiency (0.94). Conclusion: PRP injections into TMJ cavities should be considered as a low invasive, highly accessible form of treatment for various TMDs causing pain and mandible movement limitation.

Infiltração intraarticular de plasma rico em plaquetas versus ácido hialurônico em pacientes com osteoartrose primária do joelho: Ensaio clínico randomizado com resultados preliminares

Objective  The present study aimed to compare the effects of intraarticular infiltration of platelet-rich plasma with those of hyaluronic acid infiltration in the treatment of patients with primary knee osteoarthritis.

Methods  A randomized clinical trial was conducted with 29 patients who received an intraarticular infiltration with hyaluronic acid (control group) or platelet-rich plasma. Clinical outcomes were assessed using the visual analog scale for pain and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire before and after the intervention. In addition, the posttreatment adverse effects were recorded. Categorical variables were analyzed using the chi-square and Fisher exact tests, whereas continuous variables were analyzed using the Student t test, analysis of variance, and the Wilcoxon test; all calculations were performed with the Stats package of the R software.

Results  An independent analysis of each group revealed a statistical difference within the first months, with improvement in the pain and function scores, but worsening on the 6 ^th month after the procedure. There was no difference in the outcomes between the groups receiving hyaluronic acid or platelet-rich plasma. There was no serious adverse effect or allergic reaction during the entire follow-up period.

Conclusion  Intraarticular infiltration with hyaluronic acid or platelet-rich plasma in patients with primary knee gonarthrosis resulted in temporary improvement of functional symptoms and pain. There was no difference between interventions.

The aging athlete

Aging athletes, those 60 years and older, are a growing population of mature, active individuals who value sports and exercise participation throughout their lifespan. Although recommendations for younger and masters athletes have been extrapolated to this population, there remains a paucity of specific guidelines, treatment algorithms, and considerations for aging athletes. The benefits of living an active lifestyle must be weighed against the risks for unique cardiovascular, metabolic, and musculoskeletal injuries requiring diagnostic and therapeutic interventions. In this article, we review the unique cardiovascular and muscular physiology of aging athletes and how it influences the risk of specific medical conditions. We also discuss general prevention and treatment strategies. Finally, we identify areas of future research priorities and emerging treatments.

Biomaterial Integration in the Joint: Pathological Considerations, Immunomodulation, and the Extracellular Matrix

Defects of articular joints are becoming an increasing societal burden due to a persistent increase in obesity and aging. For some patients suffering from cartilage erosion, joint replacement is the final option to regain proper motion and limit pain. Extensive research has been undertaken to identify novel strategies enabling earlier intervention to promote regeneration and cartilage healing. With the introduction of decellularized extracellular matrix (dECM), researchers have tapped into the potential for increased tissue regeneration by designing biomaterials with inherent biochemical and immunomodulatory signals. Compared to conventional and synthetic materials, dECM-based materials invoke a reduced foreign body response. It is therefore highly beneficial to understand the interplay of how these native tissue-based materials initiate a favorable remodeling process by the immune system. Yet, such an understanding also demands increasing considerations of the pathological environment and remodeling processes, especially for materials designed for early disease intervention. This knowledge would avoid rejection and help predict complications in conditions with inflammatory components such as arthritides. This review outlines general issues facing biomaterial integration and emphasizes the importance of tissue-derived macromolecular components in regulating essential homeostatic, immunological, and pathological processes to increase biomaterial integration for patients suffering from joint degenerative diseases. This article is protected by copyright. All rights reserved.

Clinical Response After Treatment of Knee Osteoarthritis With a Standardized, Closed-System, Low-Cost Platelet-Rich Plasma Product: 1-Year Outcomes

Background:

Intra-articular infiltration of platelet-rich plasma (PRP) is an alternative therapeutic option to classic hyaluronic acid for the treatment of symptomatic knee osteoarthritis (KOA). However, variation in preparation methods and quality assessment of PRP makes the study of its real clinical efficacy difficult.

Purpose:

To (1) evaluate the clinical efficacy of a characterized PRP product prepared in a standardized manner and in a closed-system for the treatment of KOA and to (2) evaluate the association of the clinical response to PRP-related variables.

Study Design:

Case series; Level of evidence, 4.

Methods:

We recruited 130 patients with nonoperative KOA and evaluated them for 1 year. PRP was prepared from a donation of autologous blood, obtaining 3 aliquots of approximately 10mL of product, which were frozen, allowing platelet disruption, platelet factor release, and long-term storage, until administration. Patients were treated 3 consecutive times every 4 weeks with an intra-articular PRP knee injection under sterile conditions. Complete blood count was performed on the whole-blood sample and the processed PRP before freezing it, for product quality assessment. Patients were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and basic satisfaction scale at 3 months, 6 months, and 1 year after intervention.

Results:

Quality assessment confirmed a leukocyte-poor PRP product (white blood cell count, 0.09 ± 0.09 × 10⁹/L) with a high platelet purity (platelet count, 630.86 ± 191.75 × 10⁹/L). WOMAC scores improved, and basic satisfaction was achieved in 70% of patients. No adverse events were reported. No correlations were observed between PRP quality parameters and clinical results. PRP complete treatment production costs were €108/US$125 (€36/US$41.6 per injection).

Conclusion:

This standardized PRP production method resulted in improved WOMAC scores at 1 year postoperatively in 70% of patients with KOA. This technique was safe and affordable and ensured consecutive infiltrations with the same product to each patient.

Consecutive injections of leukocyte-rich platelet-rich plasma are effective in not only mild but also severe knee degeneration

INTRODUCTION

How can non-cultured platelet-rich plasma (PRP) therapy be the ultimate intervention in the treatment of total knee arthroplasty (TKA) -adaptive levels of knee osteoarthritis, as opposed to stem cell therapy that requires culture?

METHODS

An intra-articular injection of leukocyte-rich PRP (LR-PRP) was administered to 260 patients every 4 weeks for over four times (mean 5.8 times); they were followed up for a maximum of 24 months. The clinical evaluation used the Knee Injury and Osteoarthritis Outcome Score, visual analogue scale, and magnetic resonance imaging osteoarthritis knee score-body mass lesions to determine the therapeutic effect using the Outcome Measures in Rheumatology-Osteoarthritis Research Society International responder criteria for osteoarthritis.

RESULTS

Among those administered with LR-PRP, the responder rate was 72.0%, 78.1%, 78.1%, and 77.1% at 3, 6, 12, and 24 months, respectively.

CONCLUSIONS

Our manually prepared LR-PRP was effective following multiple consecutive injections, despite severe degeneration.

Cytokine Profiling and Intra-Articular Injection of Autologous Platelet-Rich Plasma in Knee Osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease leading to joint pain and stiffness. Due to lack of effective treatments, physical and psychological disabilities caused by OA have a detrimental impact on the patient’s quality of life. Emerging evidence suggests that intra-articular injection of platelet-rich plasma (PRP) may provide favorable results since PRP comprises not only a high level of platelets but also a huge amount of cytokines, chemokines, and growth factors. However, the precise mechanism and standardization method remain uncertain. This study aimed to examine cytokine profiling in both PRP and platelet-poor plasma (PPP) of knee OA patients and to determine the effects of PRP on OA chondrocytes and knee OA patients. PRP contained a wide variety of cytokines, chemokines, growth factors, and autologous intra-articular PRP injection resulted in favorable outcomes in knee OA patients. Significant increases in levels of IL-1, IL-2, IL-7, IL-8, IL-9, IL-12, TNF-α, IL-17, PDGF-BB, bFGF, and MIP-1β were detected in PRP compared to PPP (p < 0.001). An in vitro study showed a marked increase in proliferation in OA chondrocytes cultured with PRP, compared to PPP and fetal bovine serum (p < 0.001). In a clinical study, knee OA patients treated with PRP showed improvement of physical function and pain, assessed by physical performance, Western Ontario and McMaster Universities Arthritis Index and visual analog scale. Our findings from both in vitro and clinical studies suggest that intra-articular PRP injection in knee OA patients may be a potential therapeutic strategy for alleviating knee pain and delaying the need for surgery.

Bone marrow aspirate concentrate versus platelet-rich plasma for treating knee osteoarthritis: a one-year non-randomized retrospective comparative study

Background

Knee osteoarthritis (OA) is a debilitating condition affecting human body biomechanics and quality of life. Current standard care for knee OA leads to trivial improvement and entails multiple adverse effects or complications. Recently, investigational cell therapies injected intra-articularly, such as bone marrow aspirate concentrate (BMAC) and platelet-rich plasma (PRP), have shown safety and therapeutic potency providing patients with pain relief. In the current retrospective comparative study, we investigated the differences in pain and functional improvements in patients with symptomatic knee OA receiving intra-articular injections of BMAC vs PRP.

Methods

Pain and functionality scores were measured at baseline and at different time points post-injection over 12 months, using 3 self-administered, clinically validated questionnaires: the visual analogue scale (VAS) for assessing pain intensity, the knee injury and osteoarthritis outcome score (KOOS) for evaluating functionality and knee-related quality of life, and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) for evaluating physical function. The repeated-measures general linear model with Sidak test for pairwise comparisons was used to investigate the influence of the treatment on the score evolution within groups (between baseline and each time point) and between groups (overall).

Results

The BMAC group (n = 26 knees) significantly improved in VAS, KOOS, and WOMAC scores between baseline and 12 months (57.4, 75.88, and 73.95% mean score improvement, respectively). In contrast, the PRP group (n = 13 knees) witnessed nonsignificant improvement in all scores. BMAC, in comparison to PRP, induced significant improvement in outcomes by 29.38% on the VAS scale, 53.89% on the KOOS scale, and 51.71% on the WOMAC scale (P < .002, P < .01, P < .011, respectively).

Conclusions

Intra-articular autologous BMAC injections are safe, effective in treating pain, and ameliorate functionality in patients with symptomatic knee OA to a greater extent than PRP injections.

Graphical abstract

Intra-articular autologous BMAC therapy is safe and provides more relief to patients with symptomatic knee osteoarthritis compared to PRP therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04910-5.

Intra-Articular Drug Delivery for Osteoarthritis Treatment

Osteoarthritis (OA) is the most prevalent degenerative joint disease affecting millions of people worldwide. Currently, clinical nonsurgical treatments of OA are only limited to pain relief, anti-inflammation, and viscosupplementation. Developing disease-modifying OA drugs (DMOADs) is highly demanded for the efficient treatment of OA. As OA is a local disease, intra-articular (IA) injection directly delivers drugs to synovial joints, resulting in high-concentration drugs in the joint and reduced side effects, accompanied with traditional oral or topical administrations. However, the injected drugs are rapidly cleaved. By properly designing the drug delivery systems, prolonged retention time and targeting could be obtained. In this review, we summarize the drugs investigated for OA treatment and recent advances in the IA drug delivery systems, including micro- and nano-particles, liposomes, and hydrogels, hoping to provide some information for designing the IA injected formulations.

Cell and Cell Free Therapies in Osteoarthritis

Osteoarthritis (OA) is the most common articular disease in adults and has a current prevalence of 12% in the population over 65 years old. This chronic disease causes damage to articular cartilage and synovial joints, causing pain and leading to a negative impact on patients' function, decreasing quality of life. There are many limitations regarding OA conventional therapies-pharmacological therapy can cause gastrointestinal, renal, and cardiac adverse effects, and some of them could even be a threat to life. On the other hand, surgical options, such as microfracture, have been used for the last 20 years, but hyaline cartilage has a limited regeneration capacity. In recent years, the interest in new therapies, such as cell-based and cell-free therapies, has been considerably increasing. The purpose of this review is to describe and compare bioregenerative therapies' efficacy for OA, with particular emphasis on the use of mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP). In OA, these therapies might be an alternative and less invasive treatment than surgery, and a more effective option than conventional therapies.

Role of the osteochondral unit in the pathogenesis of osteoarthritis: focus on the potential use of clodronate

Osteoarthritis (OA) is a chronic disease characterized by inflammation and progressive deterioration of the joint. The etiology of OA includes genetic, phlogistic, dismetabolic and mechanical factors. Historically, cartilage was considered the target of the disease and therapy was aimed at protecting and lubricating the articular cartilage. The osteochondral unit is composed of articular cartilage, calcified cartilage, and subchondral and trabecular bone, which work synergistically to support the functional loading of the joint. Numerous studies today show that OA involves the osteochondral unit, with the participation therefore of the bone in the starting and progression of the disease, which is associated with chondropathy. Cytokines involved in the process leading to cartilage damage are also mediators of subchondral bone edema. Therefore, OA therapy must be based on the use of painkillers and bisphosphonates for both the control of osteometabolic damage and its analgesic activity. Monitoring of the disease of the osteochondral unit must be extensive, since bone marrow edema can be considered as a marker of the evolution of OA. In the present review we discuss some of the pathogenetic mechanisms associated with osteoarthritis, with particular focus on the osteochondral unit and the use of clodronate.

Supercritical carbon dioxide decellularized porcine cartilage graft with PRP attenuated OA progression and regenerated articular cartilage in ACLT-induced OA rats

Knee osteoarthritis (OA) is a common degenerative articular disorder and considered one of the primary causes of pain and functional disability. Knee OA is prevalent in 10% of men and 13% of women aged 60 years above. The study aims to use cartilage tissue engineering that combines the triads of decellularized porcine cartilage graft as "scaffold," plasma rich platelet (PRP) as "signal" and chondrocytes from rat as "cell" to attenuate ACLT-induced OA progression and regenerate the knee cartilage in rats. Decellularization of the porcine cartilage was characterized by hematoxylin and eosin, 4,6-Diamidino-2-phenylindole staining, scanning electron microscopy and residual DNA quantification. The protective effect of decellularized porcine cartilage graft (dPCG) was evaluated by intra-articular administration in surgically induced anterior cruciate ligament transection (ACLT) rat osteoarthritis (OA) model. Supercritical carbon dioxide technology completely decellularized the porcine cartilage. Intra-articular administration of dPCG with or without PRP significantly reduced the ACLT-induced OA symptoms and attenuated the OA progression. Pain-relief by dPCG with or without PRP was assessed by capacitance meter and improved articular cartilage damage in the rat knee was characterized by X-ray and micro-CT. Besides, the histological analysis depicted cartilage protection by dPCG with or without PRP. The repairation and attenuation effect by dPCG with or without PRP in the articular knee cartilage damage were also explored by safranin-O, type II collagen, aggrecan and SOX-9 immuno-staining. To conclude, intra-articular administration of dPCG with or without PRP is efficient in repairing the damaged cartilage in the experimental OA model.

Efficacy evaluation of acupotomy combined with platelet-rich plasma in the treatment of early and middle osteoarthritis

OBJECTIVE

To investigate the efficacy of traditional Chinese medicine acupotomy combined with platelet-rich plasma (PRP) in the treatment of early and middle osteoarthritis.

METHODS

Eighty cases of early and middle knee joint pain patients admitted in our hospital were selected in this retrospective study. They were divided into the control group and observation group according to treatment methods, with 40 cases in each group. The control group was treated with PRP, and the observation group was treated with acupotomy + PRP. Clinical response rate, visual analogue scale (VAS) pain score, Lequesne score, Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index and SF-36 quality of life score were compared between the two groups.

RESULTS

The total clinical response rate in the observation group was higher than that in control group (P<0.01). VAS pain score, knee joint WOMAC index and Lequesne score in the two groups after treatment were lower than those before treatment, and those in the observation group were lower than those in the control group (all P<0.05). SF-36 quality of life score was significantly higher in the observation group than in the control group (all P<0.001).

CONCLUSION

Acupotomy combined with PRP in the treatment of early and middle osteoarthritis can relieve pain and improve joint function, which is worthy of clinical promotion.

Extracellular Vesicles as Biological Indicators and Potential Sources of Autologous Therapeutics in Osteoarthritis

Along with cytokines, extracellular vesicles (EVs) released by immune cells in the joint contribute to osteoarthritis (OA) pathogenesis. By high-resolution flow cytometry, we characterized 18 surface markers and 4 proinflammatory cytokines carried by EVs of various sizes in plasma and synovial fluid (SF) from individuals with knee OA, with a primary focus on immune cells that play a major role in OA pathogenesis. By multiplex immunoassay, we also measured concentrations of cytokines within (endo) and outside (exo) EVs. EVs carrying HLA-DR, -DP and -DQ were the most enriched subpopulations in SF relative to plasma (25–50-fold higher depending on size), suggesting a major contribution to the SF EV pool from infiltrating immune cells in OA joints. In contrast, the CD34⁺ medium and small EVs, reflecting hematopoietic stem cells, progenitor cells, and endothelial cells, were the most significantly enriched subpopulations in plasma relative to SF (7.3- and 7.7-fold higher). Ratios of EVs derived from neutrophils and lymphocytes were highly correlated between SF and plasma, indicating that plasma EVs could reflect OA severity and serve as systemic biomarkers of OA joint pathogenesis. Select subsets of plasma EVs might also provide next generation autologous biological products for intra-articular therapy of OA joints.

Platelet-Rich Plasma Content of Active Spinal Cord Injured Patients: A Controlled Laboratory Study

OBJECTIVE

Platelet-rich plasma has potential uses for patients with spinal cord injuries. However, no study has quantified the cellular and growth factor content of platelet-rich plasma in this population. This study aimed to analyze (1) platelet-rich plasma content of spinal cord injury subjects and (2) the effect of high-intensity interval exercise on their platelet-rich plasma.

DESIGN

Ten spinal cord injury patients and 10 controls were enrolled. At rest, platelet-rich plasma was created from both groups. The spinal cord injury group then performed high-intensity interval exercise and underwent a second blood draw to create post-high-intensity interval exercise platelet-rich plasma. Complete blood counts and growth factor analysis (via enzyme-linked immunosorbent assay) was performed on all platelet-rich plasma.

RESULTS

The spinal cord injury group had lower platelets (305,700 ± 85,697/μl vs 380,800 ± 57,301/μl, P = 0.015) and transforming growth factor β (12.84 ± 1.58 vs 14.33 ± 0.63 ng/ml, P = 0.023). Four minutes of high-intensity interval exercise increased the platelets (305,700 ± 85,697/μl to 399,200 ± 96,251/μl, P = 0.004), leukocytes (906 ± 930 vs 2504 ± 3765/μl, P = 0.002) and transforming growth factor β (12.84 ± 1.58 to 14.28 ± 1.21 ng/ml, P = 0.020).

CONCLUSIONS

Spinal cord injury patients have fewer platelets and transforming growth factor β in their platelet-rich plasma at baseline compared with controls. Exercise increased platelet, leukocyte, and transforming growth factor β yield, compensating for the baseline deficits.

A Prospective Study Comparing Leukocyte-Poor Platelet-Rich Plasma Combined with Hyaluronic Acid and Autologous Microfragmented Adipose Tissue in Patients with Early Knee Osteoarthritis

The objective of this study was to compare the clinical efficacy of repeated doses of leucocyte-poor platelet-rich plasma (LP-PRP) plus hyaluronic acid (HA) to a single dose of autologous microfragmented adipose tissue (AMAT) injections in patients with early osteoarthritis (OA) symptoms. Eighty knees in 50 patients (mean age: 61.3 years) were randomly allocated into two equal groups in a nonblinded design and prospectively followed for 12 months. Group 1 received three intra-articular injections (1 month apart) using autologous LP-PRP+HA. Group 2 received a single dose of AMAT injection. Outcomes were measured by PROMs Tegner, Marx, visual analog scale, and Knee Injury and Osteoarthritis Outcome Score (KOOS) at 6 and 12 months. Both groups had significant clinical and functional improvement at 6 and 12 months. The differences between groups were statistically significant in Tegner score and KOOS symptoms (both P < 0.05) at 6 months in group 2. The test with statistically significant differences (P < 0.05) at 12 months was Tegner (P < 0.001), with group 2 having a higher median than group 1. LP-PRP+HA and AMAT lead to clinical and functional improvement at 6 and 12 months. AMAT showed better clinical results in Tegner and KOOS symptoms at 6 months and Tegner at 12 months. Understanding which therapy offers the most benefits with the least risk can significantly improve the quality of life for millions of people affected by OA. Long-term randomized controlled studies are needed to verify differences in efficacy.