Efficacy of platelet-rich plasma injections in osteoarthritis of the knee: a systematic review and meta-analysis

Factors affecting the therapeutic effects of multiple intra-articular injections of platelet-rich-plasma for knee osteoarthritis

Background

Platelet-rich-plasma (PRP) is rapidly spreading as a conservative treatment option for knee osteoarthritis (KOA), however, its therapeutic efficacy is controversial. This study aimed to investigate the factors affecting the therapeutic effect of intra-articular PRP therapy for KOA in patients who received multiple PRP injections (PRP-I).

Methods

This is a historical cohort study included 1057 knees of 701 patients who received PRP-I during KOA treatment from 2018 to 2020. The difference in visual analog scale (VAS) scores before and after PRP-I was defined as the amount of change in VAS (ΔVAS). A linear mixed-effects model was employed with ΔVAS as a random effect and age, sex, BMI, KL classification, pre-treatment VAS, treatment duration, and the number of PRP injections as fixed effects. Evaluations using the Kellgren-Lawrence (KL) classification were added.

Results

Age, KL grade, and VAS score before treatment and after three, four, and five PRP-I were significantly associated with ΔVAS score. According to KL grade, age was significantly associated with ΔVAS score in the KL grade 4 group. VAS score before treatment was significantly associated with ΔVAS score, regardless of KL grade. Three-time PRP-I were significantly associated with ΔVAS in the KL-grade 1 and 2 groups. For KL grade 4, two or more PRP-I were significantly associated with the high efficacy.

Conclusions

Age, pain before treatment, KL grade and number of injections were associated with pain reduction after intra-articular PRP-I for KOA treatment. Pain reduction can be expected after PRP-I when patients are younger or experience severe pain before treatment. Three-time PRP-I are recommended to reduce pain in early-stage KOA and more than three times in advanced-stage KOA.

Trial registration

Retrospectively registration.

Course-based intra-articular injection of medical chitosan mitigates excessive deposition of triacylglycerides in the synovial tissue of the knee osteoarthritis

BACKGROUND

This study aimed to investigate the clinical efficacy of intra-articular injections of medical chitosan for treating knee osteoarthritis (KOA) and measure the lipid metabolism profiles of the synovial tissue.

METHODS

Sixty patients with KOA undergoing conservative treatment were recruited and randomized into two groups: one without pharmacological intervention (OA group) and the other receiving course-based intra-articular medical chitosan injections (CSI group). Quantitative lipidomic profile of synovial tissue was analyzed. Functional scores, including Kellgren-Lawrence rating (K-L), Visual Analog Scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scoring, and American Knee Society (AKS) scoring were conducted.

RESULTS

Survival from the initial conservative treatment to final knee arthroplasty was significantly longer in the CSI group compared to the OA group. Except for the presurgery VAS score, no statistically significant differences were observed in the other scores, including K-L, initial VAS, WOMAC, and AKS. However, the CSI group experienced more reductions in AKS-Knee subscores compared to the OA group. Compared to the CSI group, the OA group exhibited a significant upregulation in most differential lipids, particularly triacylglycerides (TAGs, 77%). The OA group had notably higher levels of long-chain unsaturated fatty acids.

CONCLUSION

Intra-articular injection of medical chitosan significantly prolongs the survival period before knee arthroplasty and reduces the deposition of TAGs metabolites.

A systematic review and meta-analysis of the efficacy of platelet-rich plasma products for treatment of equine joint disease

BACKGROUND

Equine joint disease including septic arthritis (SA) and osteoarthritis (OA) is a critical cause of equine lameness. Platelet-rich plasma (PRP) is one of the most popular regenerative therapies to treat equine OA, even SA, but the evidence in support of the treatment is conflicting.

OBJECTIVES

The aim of the study was to systematically review the current evidence on PRP products used for SA and OA, as well as the efficacy of PRP products as treatment for OA on the basis of a meta-analysis of the available literature.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A systematic search of relevant databases (PubMed, Web of Science, Scopus) was performed to identify studies published from 2013 to 2023, in accordance with the PRISMA guidelines. Randomised controlled trials, non-randomised trials and controlled laboratory studies that used at least one type of PRP products were included. Dichotomous outcomes were presented using odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

A total of 21 publications were identified in the systematic review and 5 of them in the meta-analysis. These publications involved various types of PRP products and reported different outcomes. Although most of the studies were associated with a high risk of bias, the overall estimated effect was consistent with a significant improvement in the PRP products treatment group compared with the control group (OR: 15.32; 95% CI: 3.00-78.15; p < 0.05). There was a significant improvement in clinical performance outcomes between the groups (OR: 36.64; 95% CI: 3.69-364.30; p < 0.05).

CONCLUSION

PRP products as intra-articular treatment are likely efficacious for treatment of equine OA and have potential for treating SA. These conclusions might be affected by the limited number of randomised controlled studies and high variability of different types of PRP products. To better evaluate the efficacy of PRP, a widely recognised classification system and the utilisation of randomised, blinded, equivalency or non-inferiority trials are required.

Effectiveness of platelet-rich plasma in partial-thickness rotator cuff tears: a systematic review

IMPORTANCE

Partial-thickness rotator cuff tears (PTRCTs) commonly affect overhead athletes, leading to a decline in sports performance. Platelet-rich plasma (PRP) is being explored as an alternative treatment modality for individuals with PTRCTs to reduce discomfort and enhance functional recovery. We conducted a systematic review study of randomized controlled clinical trials to determine the effectiveness of PRP in treating PTRCTs.

AIM

To determine the effectiveness of PRP in treating PTRCTs.

EVIDENCE REVIEW

We conducted a comprehensive literature search for randomized controlled trials (RCTs) that compared the effectiveness of PRP with eccentric exercise and placebo injections as treatments for PTRCTs. We searched databases such as the Cochrane Library, Web of Science, PubMed, and EMBASE. The visual analog scale (VAS) score, American Shoulder and Elbow Surgeon (ASES) score, and Constant-Murley Score (CMS) was utilized as an outcome measure. Statistical analysis was performed using RevMan 5.3 software.

FINDINGS

Our meta-analysis included 12 studies involving 762 patients. At six weeks post-treatment, the PRP group had significantly higher VAS scores compared to the control group, indicating improvement (standard mean difference (SMD): -2.04 [95% confidence interval (CI): -4.00 to -0.08], I2 ​= ​97%, P-value ​= ​0.04). Patients who received PRP showed statistically significant improvements in VAS scores at 3 months and 6 months follow-up (SMD, -1.78 [95% CI: -3.03 to -0.52], I2 ​= ​96%, P-value ​= ​0.005) (SMD: -2.26 [95% CI: -3.77 to -0.76], I2 ​= ​97%, P-value ​= ​0.003). A statistically significant difference was also observed in VAS scores at the long-term 1-year follow-up (SMD: -2.27 [95% CI: -4.07 to -0.47]; I2 ​= ​98%; P-value ​= ​0.031). There were statistically significant differences in ASES scores and CMS scores in the short-term (SMD: 1.21 [95% CI: 0.19 to 2.24], I2 ​= ​96%, P-value ​= ​0.02) (SMD, 2.01 [95% CI: 0.14 to 3.88], I2 ​= ​97%, P-value ​= ​0.04). However, in the long-term ASES and CMS scores did not show any statistical significance (SMD: 2.06 [95% CI: -0.54 to 4.65], I2 ​= ​99%, P-value ​= ​0.12) (SMD: 4.36 [95% CI: -5.48 to 14.21], I2 ​= ​99%, P-value ​= ​0.39).

CONCLUSIONS AND RELEVANCE

Our findings suggest that PRP treatment is effective in reducing pain for individuals with PTRCTs, providing benefits in the short and long term. However, its impact on functional recovery appears somewhat constrained and doesn't endure over time. Additionally, significant heterogeneity exists among studies, encompassing variations in PRP composition and control group treatments. Consequently, we conclude that compelling evidence for symptom improvement in PTRCT patients following PRP treatment remains elusive.

LEVEL OF EVIDENCE

Level I.

Efficacy Analysis of Arthroscopic Surgery Combined with Intra-articular Chitosan Injection for Stage II-III Knee Osteoarthritis in Patients with Abnormal Body Weight

OBJECTIVE

Weight is an influential factor in knee osteoarthritis (KOA). However, the effect of abnormal body weight on chitosan's efficacy in treating KOA is unclear. This study aimed to explore the differences in the effectiveness of arthroscopic surgery combined with intra-articular chitosan injection for KOA in patients with abnormal body weight.

METHODS

Patients with stage II-III KOA (Kellgren-Lawrence rating, K-L) undergoing arthroscopic surgery were recruited for this clinical study from January 2020 to September 2021. Based on body mass index (BMI) and intra-articular chitosan injection, patients with KOA undergoing arthroscopic surgery (138 patients) were divided into four groups: low-weight-non-injection (Lw-N, BMI <18.5); low-weight-chitosan injection (Lw-CS, BMI <18.5); overweight-non-injection (Ow-N, BMI ≥25); overweight-chitosan injection (Ow-CS, BMI ≥25). A 2-year follow-up was conducted to evaluate various indicators, including the visual analogue scale (VAS) and the Western Ontario and McMaster Universities osteoarthritis index score (WOMAC). Statistical analyses were performed using relevant parametric or non-parametric tests.

RESULTS

In total, 138 patients with KOA were included in this study. There were no significant differences in gender, age, and incidence of chronic residual pain after arthroscopy among the four groups (p > 0.05). The proportion of patients undergoing subsequent knee arthroplasty during the 2-year follow-up period was significantly higher in the Ow-CS group (20/35) than in the Lw-CS group (12/39) (p < 0.05). The K-L rating showed an overall increasing trend over time, with the K-L rating in the Ow-N and Ow-CS groups significantly higher than that in the Lw-CS group at the final follow-up (p < 0.05). VAS and WOMAC scores significantly decreased at 1 and 3 months post-arthroscopy and then increased. One month after arthroscopy, VAS was significantly lower (p < 0.05) in the intra-articular chitosan injection groups (Lw-CS and Ow-CS) compared with the non-injection groups (Lw-N and Ow-N). VAS was lower in the Ow-CS group than in the Lw-CS group (p < 0.05). There was no significant difference in WOMAC between the intra-articular chitosan injection and non-injection groups at each time point (Lw-N vs. Lw-CS, Ow-N vs. Ow-CS, p > 0.05).

CONCLUSION

Arthroscopic surgery combined with intra-articular chitosan injection shows short-term positive effects in treating KOA. Intra-articular chitosan injection appears to have a greater short-term pain relief effect in obese patients.

Is There a Need for an Exogenous Activator Along with PRP for Early Knee Osteoarthritis? A Triple-Blinded Randomized Control Trial

Background

In addition to other variables associated with PRP injections for Knee Osteoarthritis (OA), some confusion exists about the role of exogenous activators. The current study looks at matched groups getting PRP injections with or without activator (Calcium gluconate) in early knee OA patients.

Methods

Patients of early OA knee meeting inclusion criteria were randomly divided into 2 groups; Group A (43 patients) received 8 ml PRP injection alone, and Group B (48 patients) received 8 ml PRP along with 2 ml Calcium gluconate as activator. The patients were evaluated at baseline, 6 weeks, 3 months and 6 months for WOMAC Pain and Total WOMAC scores; secondary variables assessed were VAS score and patient satisfaction.

Results

The baseline characteristics of both groups were comparable. Leucocyte-depleted PRP with 5 times concentration and average absolute platelet numbers of 7.144 billion per knee was injected. Mean Pain WOMAC scores decreased in both groups from baseline (group A-8.68, group B-9.09) to final follow-up (group A-4.67, group B-5.11). Similarly, Mean Total WOMAC scores decreased from baseline (group A-37.81, group B-37.41) to (group A-21, group B-21.36) at the final follow-up in both groups. There was no significant difference between both groups, and both showed similar trends. Similar findings were noted for VAS scores. Patient satisfaction was also not different (group A, 90.69%, group B, 89.58%) at the end of 6 months.

Conclusion

Our study concluded doubtful role of adding exogenous activator to PRP preparation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-024-01159-7.

Efficacy of Intraoperative Platelet-Rich Plasma After Meniscal Repair: Systematic Review and Meta-analysis

Background

Meniscal injuries frequently require surgical intervention to restore knee joint function and stability. Intraoperative platelet-rich plasma (PRP) injection has emerged as a potential adjunctive therapy to enhance tissue healing post-meniscal repair. This systematic review and meta-analysis aimed to evaluate the efficacy of PRP in terms of pain relief, functional recovery, and overall success rates in patients undergoing meniscal repair procedures.

Methods

A comprehensive search strategy was employed to identify relevant studies across Scopus, PubMed, Embase, and the Cochrane Library databases. The inclusion criteria encompassed human studies, including randomized controlled trials (RCTs), cohorts, and case-control studies, focusing on intraoperative platelet-rich plasma (PRP) use post-meniscal repair and reporting outcomes related to pain, functionality, and cure rates. Exclusion criteria comprised animal studies, non-English publications, studies lacking relevant outcome measures, and those with insufficient data. Two reviewers independently screened titles and abstracts, resolving disagreements through consensus or consultation with a third reviewer, followed by a full-text assessment for potentially eligible studies. Data extraction was conducted independently by two reviewers using a standardized form. The reliability of observational studies was evaluated using the Newcastle-Ottawa Scale. Subgroup analyses and pooled effect estimates for main outcomes were computed using RevMan 5.3, a meta-analysis tool.

Results

The demographic analysis revealed that the PRP group had an average age of 41.39 years, while the control group had an average age of 42.1 years. In terms of gender distribution, the PRP group consisted of 61 men and 29 women, while the control group had 62 men and 34 women. Pain ratings showed a preference for PRP with a mean difference of 4.83 (p = 0.13). However, there was no significant difference in Lysholm scores (mean difference: - 0.44, p = 0.91) or IKDC scores (mean difference: 2.80, p = 0.14) between the PRP and control groups. Similarly, ROM measures did not show a statistically significant difference, with a mean difference of 2.80 (p = 0.18). Additionally, there was no significant distinction in failure rates between the PRP and control groups, as indicated by a weighted mean difference of 0.71 (p = 0.52). These findings suggest that while PRP may offer some benefits in pain relief, its impact on functional recovery, range of motion, and failure rates following meniscal repair procedures is inconclusive.

Conclusion

The current evidence regarding the effect of intraoperative platelet-rich plasma (PRP) injection on patients undergoing meniscal repair remains inconclusive. While some studies suggest potential benefits in terms of pain relief and functional recovery, others show no significant differences compared to control groups. The impact of PRP therapy on overall success rates, including rates of re-tear and revision surgery, is also uncertain. Further well-designed randomized controlled trials with larger sample sizes are needed to provide more robust evidence and guide clinical practice in orthopedic surgery.

Regenerative therapy in geriatric patients with low back pain

Low back pain (LBP) is a prevalent and debilitating condition, particularly among older adults, with degenerative spinal disease being a major contributor. Regenerative therapy, which aims to repair and regenerate damaged spinal structures, has shown promise in providing long-term pain relief and functional improvement. This review focuses on the application and efficacy of regenerative therapies such as mesenchymal stem cells, platelet-rich plasma, and atelocollagen in older patients with LBP. Despite the potential benefits, there is a notable scarcity of studies specifically targeting the older population, and those available often have small sample sizes and limited age-related analyses. Our findings underscore the need for more comprehensive and well-designed clinical trials to evaluate the effectiveness of these therapies in older patients. Future research should prioritize larger age-specific studies to establish regenerative therapy as a viable and effective treatment option for LBP in the aging population.

Does the Combination of Platelet-rich Plasma and Supervised Exercise Yield Better Pain Relief and Enhanced Function in Knee Osteoarthritis? A Randomized Controlled Trial

BACKGROUND

Knee osteoarthritis is a leading cause of disability with substantial healthcare costs, and efficient nonsurgical treatment methods are still needed. Platelet-rich plasma (PRP) injections and exercise therapy are used frequently in clinical practice. Whether PRP or PRP combined with exercise is more effective than exercise alone is unclear.

QUESTIONS/PURPOSES

(1) Which treatment relieves knee osteoarthritis pain better: PRP alone, exercise, or PRP combined with exercise? (2) Does PRP alone, exercise, or PRP combined with exercise yield better results in terms of the WOMAC score, performance on the 40-m fast-paced walk test and stair climbing test, and the SF-12 health-related quality of life score?

METHODS

In this randomized, controlled, three-arm clinical trial, we recruited patients with mild-to-moderate (Kellgren-Lawrence Grade II or III) knee osteoarthritis with a minimum of 3 points on the 11-point numeric rating scale for pain. During the study period, 157 patients with a diagnosis of knee osteoarthritis were screened and 84 eligible volunteers were enrolled in the study. Patients were randomly allocated (1:1:1) into either the exercise group (28), PRP group (28), or PRP + exercise group (28). Follow-up proportions were similar between the groups (exercise: 89% [25], PRP: 86% [24], PRP + exercise: 89% [25]; p = 0.79). All patients were analyzed in an intention-to-treat manner. There were no between-group differences in age, gender, arthritis severity, and baseline clinical scores (pain, WOMAC, functional performance tests, and health-related quality of life). The exercise group underwent a 6-week structured program consisting of 12 supervised individual sessions focused on strengthening and functional exercises. Meanwhile, the PRP group received three weekly injections of fresh, leukocyte-poor PRP. The PRP + exercise group received a combined treatment with both interventions. The primary outcome was knee pain over 24 weeks, measured on an 11-point numeric rating scale for pain (ranging from 0 to 10, where 0 represents no pain and 10 represents the worst pain, with a minimum clinically important difference [MCID] of 2). The secondary outcome measures included the WOMAC index (ranging from 0 to 100, with lower scores indicating a lower level of disability and an MCID of 12), the durations of the 40-meter fast-paced walk test and stair climbing test, and the SF-12 health-related quality of life score. For the a priori sample size calculation, we used the numeric rating scale score for pain at 24 weeks as the primary outcome variable. The MCID for the numeric rating scale was deemed to be 2 points, with an estimated standard deviation of 2.4. Based on sample size calculations, a sample of 24 patients per group would provide 80% power to detect an effect of this size between the groups at the significance level of p = 0.05.

RESULTS

We found no clinically important differences in improvements in pain-defined as ≥ 2 points of 10-at 24 weeks when comparing exercise alone to PRP alone to PRP + exercise (1.9 ± 0.7 versus 3.8 ± 1.8 versus 1.4 ± 0.6; mean difference between PRP + exercise group and exercise group -0.5 [95% confidence interval -1.2 to 0.4]; p = 0.69). Likewise, we found no differences in WOMAC scores at 24 weeks of follow-up when comparing exercise alone to PRP alone to PRP + exercise (10 ± 9 versus 26 ± 20 versus 7 ± 6; mean difference between PRP + exercise group and exercise group -3 [95% CI -12 to -5]; p = 0.97). There were no differences in any of the other secondary outcome metrics among the PRP + exercise and exercise groups.

CONCLUSION

PRP did not improve pain at 24 weeks of follow-up in patients with mild-to-moderate knee osteoarthritis compared with exercise alone. Moreover, exercise alone was clinically superior to PRP alone, considering function and the physical component of health-related quality of life. Despite the additional costs and endeavors related to PRP products, the combination of PRP and exercise did not differ from exercise alone. The results of this randomized controlled trial do not support the use of PRP injections in the treatment of patients diagnosed with mild-to-moderate knee osteoarthritis. Consequently, exercise alone is the recommended treatment for reducing pain and enhancing function throughout this timeframe.

LEVEL OF EVIDENCE

Level I, therapeutic study.

Most Publications Regarding Platelet-Rich Plasma Use in the Knee Are From Asia, Investigate Injection for Osteoarthritis, and Show Outcome Improvement: A Scoping Review

PURPOSE

To evaluate and synthesize the available literature related to platelet-rich plasma (PRP) treatment of knee pathologies and to provide recommendations to inform future research in the field.

METHODS

PubMed, CINAHL, and Scopus databases were queried on October 6, 2023. All identified citations were collated and uploaded into Covidence for screening and data extraction. Studies were included if they were human studies published in English with adult cohorts that received PRP as a procedural injection or surgical augmentation for knee pathologies with patient-reported outcome measures (PROMs) and level of evidence Levels I-IV.

RESULTS

Our search yielded 2,615 studies, of which 155 studies from 2006 to 2023 met the inclusion criteria. Median follow-up was 9 months (±11.2 months). Most studies (75.5%) characterized the leukocyte content of PRP, although most studies (86%) did not use a comprehensive classification scheme. In addition, most studies were from Asia (50%) and Europe (32%) and were from a single center (96%). In terms of treatment, 74% of studies examined PRP as a procedural injection, whereas 26% examined PRP as an augmentation. Most studies (68%) examined treatment of knee osteoarthritis. Many studies (83%) documented significant improvements in PROMs, including 93% of Level III/IV evidence studies and 72% of Level I/II evidence studies, although most studies (70%) failed to include minimal clinically important difference values. The visual analog scale was the most-used PROM (58% of studies), whereas the Short Form Health Survey 36-item was the least-used PROM (5% of studies).

CONCLUSIONS

Most published investigations of knee PRP are performed in Asia, investigate procedural injection for osteoarthritis, and show significant outcome improvements. In addition, this review highlights the need for better classification of PRP formulations.

LEVEL OF EVIDENCE

Level IV, scoping Review of level I-IV studies.

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.

Current state of systematic reviews for platelet-rich plasma use in knee osteoarthritis

BACKGROUND

Knee osteoarthritis (KOA) is a highly prevalent musculoskeletal disorder affecting millions of people. To date, there is no curative treatment for KOA other than joint arthroplasty. However, treatments such as platelet-rich plasma (PRP) have been proposed as a possible therapy, with increasing interest over the last decade. To date, there are no evidence-based guidelines in the use of PRP therapy for KOA, but there are numerous studies and systematic reviews (SRs) evaluating the usage of PRP in KOA. Since SRs are of great importance for clinical decision-making, it is necessary to access their methodological quality before any valid conclusions can be made. This study will evaluate the methodological quality of SRs on PRP therapy for KOA using a validated assessment tool known as AMSTAR 2, "A MeaSurement Tool to Assess systematic Reviews".

HYPOTHESIS

It is hypothesized that the methodological quality of SRs will be moderate, whereby most of the SRs will provide an accurate summary of the results but will include more than one critical weakness as defined by the AMSTAR 2 checklist.

PATIENTS AND METHODS

The MEDLINE, EMBASE, PubMed and Cochrane databases were searched from inception to May 2023. Two independent reviewers selected SRs that investigated the use of injection therapies for KOA. Descriptive statistical analysis was performed. AMSTAR 2 assessment was completed independently by the same reviewers. Cohen's kappa was calculated to measure interrater reliability. The quality of the studies was rated as "high", "moderate", "low", and "critically low". The overall confidence assessment was tabulated.

RESULTS

Forty-one SRs were included in the analysis. The Cohen kappa was 0.88, indicating high interrater reliability. There were no "high" quality SRs identified. Seven SRs (17%) were of "low" quality, while the remainder (34 SRs, 83%) were rated as "critically low".

CONCLUSION

The methodological quality of the selected SRs was suboptimal. Clinicians should critically appraise the SRs and interpret their conclusions with caution before making clinical decisions. This study supports future work of high-quality SRs regarding the use of PRP injections for KOA.

LEVEL OF EVIDENCE

II.

Comparison of Conventional Dose Versus Superdose Platelet-Rich Plasma for Knee Osteoarthritis: A Prospective, Triple-Blind, Randomized Clinical Trial

Background

Confusion persists regarding the ideal dosage of platelet-rich plasma (PRP) injection for knee osteoarthritis (OA).

Purpose/Hypothesis

The purpose of the study was to compare the efficacy of 2 different single-injection PRP dosages in patients with early knee OA-a conventional 4 mL dose and a superdose of 8 mL. It was hypothesized that 8 mL of PRP would be superior to 4 mL of PRP in this patient population.

Study Design

Randomized clinical trial; Level of evidence, 1.

Methods

Patients with early knee OA (Kellgren-Lawrence grades 1 and 2) who met the inclusion criteria were randomly divided into 2 groups: Group A (n = 50 knees) received a 4-mL PRP injection, and group B (n = 49 knees) received an 8-mL PRP injection, both prepared using the same procedure. Patients were evaluated at the baseline, 6 weeks, 3 months, and 6 months using the Western Ontario and McMaster Universities Arthritis Index (WOMAC), the WOMAC-Pain subscale, the visual analog scale for pain, the Knee injury and Osteoarthritis Outcome Score, and patient satisfaction, and results were compared between the groups.

Results

The baseline characteristics of the 2 groups were comparable (group A: mean age, 51.96 ± 6.93 years; group B: mean age, 49.12 ± 9.8 3 years). Leucocyte-depleted PRP with 3.5 times concentration (final product platelet concentration, 706.74 × 103-μL) was injected. The mean absolute platelet count injected was 2.82 ± 0.0012 billion in group A and 5.65 ± 0.0022 billion in group B. All patient-reported outcome scores improved significantly in both groups from the baseline to the final follow-up (P < .001), with overall trends and results significantly better in group B than in group A (P < .001). Patient satisfaction at the 6-month follow-up was also better in group B (96%) compared with group A (68%). Short (2 to 7 days) self-limiting complications, such as pain and stiffness, occurred more often in group B (P < .001).

Conclusion

Patients with early knee OA had significantly better improvement in pain and function when treated with an 8-mL injection of PRP compared with a 4-mL injection of PRP. The larger dose of PRP had approximately twice the number of platelets.

Registration

CTRI/2020/02/023403 (Clinical Trials Registry-India identifier).

The use of platelet-rich plasma in pathologies of the foot and ankle: A comprehensive review of the recent literature

Platelet-rich plasma (PRP) is an autologous serum containing higher concentrations of platelets and growth factors above normal blood. The process of obtaining PRP involves the extraction of blood from the patient which is then centrifuged to obtain a concentrated suspension of platelets. PRP continues to evolve as a potential treatment modality with many applications in orthopaedic surgery. The therapeutic components of PRP possess numerous theoretical regenerative properties. The present manuscript outlines how PRP is prepared, noting the tremendous variability between preparation protocols. Given the growing body of evidence examining the use of PRP in pathologies of the foot and ankle, we assess its efficacy as it relates to our field. Specifically, we evaluate the literature in the past five years regarding the role of PRP in treating plantar fasciitis, Achilles tendinopathy, insertional Achilles tendinitis, Achilles tendon ruptures, osteochondral lesions of the talus, hallux rigidus, and ankle osteoarthritis.

Role of platelet rich plasma in management of early knee osteoarthritis pain: A retrospective observational study

Introduction

Knee joint osteoarthritis is a well-known cause of pain and disability in patients above 40 years of age. It is treated by use of non-steroidal inflammatory drugs, corticosteroids, glucosamine, chondroitin sulfate, physiotherapy with limited success. The platelet rich plasma (PRP) contains a large amount of platelet derived growth factors, cytokines and anti-inflammatory molecules which showed promising results in recent studies to relieve pain of knee joint osteoarthritis. The present study aims to determine the efficacy of intraarticular PRP for pain relief and functional improvement in patients with early knee joint osteoarthritis.

Methods

It is a retrospective observation study involving patients who underwent single intraarticular administration of PRP for knee pain with Kellgren-Lawrence (KL) grades I or II knee joint osteoarthritis. The Visual analogue scale (VAS) score and Oxford knee score (OKS) were recorded pre-procedure and at 1- and 6-month post-procedure.

Results

A total of 31 patients (20 females, 11 males) underwent PRP therapy for knee pain (16 kL grade I, 15 kL grade II). The mean age and duration of symptoms were of 53.9 years (range: 79-42 years) and 5.53 ± 2.35 years respectively. There was a significant reduction (p < 0.05) in VAS scores from pre-procedure (68.06 ± 8.33) to post procedure at 1 month (37.74 ± 11.16) and 6 months (54.52 ± 11.78). There was also significant improvement (p < 0.05) in OKS score from pre-procedure (31.1 ± 3.47) to post-procedure at 1 month (39.06 ± 3.37) and 6 months (34.10 ± 3.75). No adverse effects were reported in patients during the study period.

Conclusion

This small retrospective study suggests that a single administration of intraarticular PRP may be safe and effective for pain relief and functional improvement for up to 6 months in patients of early-stage osteoarthritis.

Clinical and Biochemical Implications of Hyaluronic Acid in Musculoskeletal Rehabilitation: A Comprehensive Review

Hyaluronic acid (HA) naturally occurs as a biopolymer in the human body, primarily in connective tissues like joints and skin. Functioning as a vital element of synovial fluid, it lubricates joints, facilitating fluid movement and diminishing bone friction to protect articular well-being. Its distinctive attributes encompass notable viscosity and water retention capacities, ensuring flexibility and absorbing shock during motion. Furthermore, HA has gained significant attention for its potential benefits in various medical applications, including rehabilitation. Ongoing research explores its properties and functions, especially its biomedical applications in several clinical trials, with a focus on its role in improving rehabilitation outcomes. But the clinical and biochemical implications of HA in musculoskeletal rehabilitation have yet to be fully explored. This review thoroughly investigates the properties and functions of HA while highlighting its biomedical applications in different clinical trials, with a special emphasis on its role in rehabilitation. The presented findings provide evidence that HA, as a natural substance, enhances the outcomes of musculoskeletal rehabilitation through its exceptional mechanical and biochemical effects.

SAS-PRP Study: A Real-Life Satisfaction Assessment in Patients with Cartilage Lesions of the Knee Treated by Platelet-Rich Plasma

Platelet-rich plasma (PRP) is a rising therapy treating locomotor system lesions such as knee osteoarthritis. The objective of this study was to evaluate patients' satisfaction 6 to 12 months after a PRP injection for cartilage lesions of their knee under real-life conditions. Patients' satisfaction was assessed by a specific questionnaire named SATMED-Q©, which explores six different dimensions of a given treatment. In addition, pain and function were assessed thanks to VAS pain, WOMAC, and IKDC scores. Responders were identified through the OMERACT-OARSI criteria. We observed excellent satisfaction after a PRP injection with a SATMED-Q© score of 80.81% 6 to 12 months after the procedure. Even when there was no significant improvement in pain and function scores, 52% of the evaluated population fulfilled the OMERACT-OARSI criteria and were considered responders. According to the sub-group analysis, patients with less osteoarthritis damage (i.e., Kellgren-Lawrence grades 1-2) and older study subjects (i.e., >40 years old) with focal chondropathy had benefited most from their PRP injection. Thus, platelet-rich plasma seems to be a well-tolerated and efficient therapy for cartilage lesions of the knee.

Clinical Applications of PRP: Musculoskeletal Applications, Current Practices and Update

Musculoskeletal tissues are often subjected to deleterious effects stemming from traumatic injuries or degenerative pathologies, which can impede the body's natural repair response. The advent of regenerative medicine has emerged as a promising therapeutic approach in modern patient care. Among the interventions in this cutting-edge field, platelet-rich plasma (PRP) and cell-based therapies, such as mesenchymal stem cells, have garnered significant attention. In this article, we endeavor to provide an overview of the current practices and recent developments in PRP therapy, with a particular emphasis on the clinical applications for musculoskeletal pathologies.

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.

Infiltration therapy in the context of cartilage surgery

Guideline-based surgical cartilage therapy for focal cartilage damage offers highly effective possibilities to sustainably reduce patients' complaints and to prevent or at least delay the development of early osteoarthritis. In the knee joint, it has the potential to reduce almost a quarter of the arthroses requiring joint replacement caused by cartilage damage. Biologically effective injection therapies could further improve these results. Based on the currently available literature and preclinical studies, intra- and postoperative injectables may have a positive effect of platelet-rich plasma/fibrin (PRP/PRF) and hyaluronic acid (HA) on cartilage regeneration and, in the case of HA injections, also on the clinical outcome can be assumed. The role of a combination therapy with use of intra-articular corticosteroids is lacking in the absence of adequate study data and cannot be defined yet. With regard to adipose tissue-based cell therapy, the current scientific data do not yet justify any recommendation for its use. Further studies also regarding application intervals, timing and differences in different joints are required.

Culture-expanded mesenchymal stromal cell therapy: does it work in knee osteoarthritis? A pathway to clinical success

Osteoarthritis (OA) is a degenerative multifactorial disease with concomitant structural, inflammatory, and metabolic changes that fluctuate in a temporal and patient-specific manner. This complexity has contributed to refractory responses to various treatments. MSCs have shown promise as multimodal therapeutics in mitigating OA symptoms and disease progression. Here, we evaluated 15 randomized controlled clinical trials (RCTs) and 11 nonrandomized RCTs using culture-expanded MSCs in the treatment of knee OA, and we found net positive effects of MSCs on mitigating pain and symptoms (improving function in 12/15 RCTs relative to baseline and in 11/15 RCTs relative to control groups at study endpoints) and on cartilage protection and/or repair (18/21 clinical studies). We examined MSC dose, tissue of origin, and autologous vs. allogeneic origins as well as patient clinical phenotype, endotype, age, sex and level of OA severity as key parameters in parsing MSC clinical effectiveness. The relatively small sample size of 610 patients limited the drawing of definitive conclusions. Nonetheless, we noted trends toward moderate to higher doses of MSCs in select OA patient clinical phenotypes mitigating pain and leading to structural improvements or cartilage preservation. Evidence from preclinical studies is supportive of MSC anti-inflammatory and immunomodulatory effects, but additional investigations on immunomodulatory, chondroprotective and other clinical mechanisms of action are needed. We hypothesize that MSC basal immunomodulatory "fitness" correlates with OA treatment efficacy, but this hypothesis needs to be validated in future studies. We conclude with a roadmap articulating the need to match an OA patient subset defined by molecular endotype and clinical phenotype with basally immunomodulatory "fit" or engineered-to-be-fit-for-OA MSCs in well-designed, data-intensive clinical trials to advance the field.

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.

Relationship Between the Underlying Factors and the Treatment Results of Platelet-Rich Plasm (PRP) Injection in Degenerative Knee Disease; A Blinded Randomized Study

Background: To investigate the therapeutic effects of PRP injection + conservative treatment as the intervention group versus normal saline injection + conservative treatment as the control group. Objectives: This study we determined the effects of underlying factors, including age, gender, and Body Mass Index (BMI), on the therapeutic effects of PRP. Methods: In this single-blinded randomized clinical trial, 60 patients with grade 2 knee OA with an age of 40 - 65 years were enrolled. In the intervention group, leukocyte-poor PRP with double spinning, and in the control group, normal saline was injected with a similar protocol. All patients in both groups were also provided with a conservative protocol, including oral celecoxib 100 mg BID for four weeks, modifying physical activity, and 15 sessions of physiotherapy. Results: Demographic characteristics (age, gender, and BMI) and pre-treatment scores were similar between the two groups (all P > 0.05). The WOMAC score was improved from pre-treatment to first week post-treatment in both groups (from 54.89 ± 3.4 to 64.9 ± 3.7 in the intervention group and from 53.7 ± 3.1 to 63.8 ± 3.9 in the control group). It means that PRP + conservative treatment was effective, similar to normal saline + conservative treatment. After adjusting BMI as an underlying variable, it was indicated that in the patients with lower BMI, PRP + conservative provided a better outcome in comparison to saline + conservative treatment (P = 0.014 and P = 0.019, respectively). Also, the comparison of functional scores changes with age as an underlying variable, demonstrating that younger cases obtained a better response from PRP + conservative rather than normal saline + conservative (P = 0.012 and P = 0.007, respectively). Conclusions: PRP seems to be an appropriate choice for treatment of moderate osteoarthritis, especially in younger patients and those with lower BMI.

How Does Platelet-Rich Plasma Compare Clinically to Other Therapies in the Treatment of Knee Osteoarthritis? A Systematic Review and Meta-analysis

BACKGROUND

There has been an increase in interest in the use of biological therapies in orthopaedic conditions such as knee osteoarthritis. Platelet-rich plasma (PRP) is one of these therapies, but it still lacks consistent results.

PURPOSE

To evaluate the effects (benefits and harms) of PRP intra-articular injection compared with other nonsurgical methods for the treatment of knee osteoarthritis.

STUDY DESIGN

Systematic review and meta-analysis of randomized and quasi-randomized controlled trials; Level of evidence, 2.

METHODS

Three electronic databases were searched to identify relevant studies published before January 2021. The primary outcomes were pain, function, and failure of treatment. Risks of bias of all trials were assessed using a Cochrane risk of bias tool. The Grading of Recommendations Assessment, Development and Evaluation System was used to assess the quality of evidence of included studies.

RESULTS

A total of 40 studies with 3035 participants were included. Analysis of this review focused on comparing PRP with hyaluronic acid, corticosteroid, and saline, as we believe they are the most relevant comparisons with the most studies available. At 6-month follow-up, PRP was as effective as and in some studies more effective than other therapies regarding pain, function, and stiffness. However, current evidence is of low or very low quality and is based on trials with high risk of bias and great heterogeneity among them. No significant difference among treatments was found concerning major adverse events and treatment failure.

CONCLUSION

Although studies suggest that PRP may be more effective than or at least as effective as other modalities of nonsurgical treatment for knee osteoarthritis in terms of pain, function, and adverse events, serious limitations and methodological flaws are considerable in the current literature. Therefore, the authors are not able to make recommendations for clinical practice regarding PRP for knee osteoarthritis.

The use of platelet-rich plasma in studies with early knee osteoarthritis versus advanced stages of the disease: a systematic review and meta-analysis of 31 randomized clinical trials

INTRODUCTION

Reports have concluded that platelet-rich plasma (PRP) is an effective and safe biological approach to treating knee osteoarthritis (OA). However, the effectiveness of PRP in advanced stages of the disease is not entirely clear. The purpose of this study was to evaluate whether the use of PRP would be as effective in studies with early-moderate knee OA patients compared to studies including patients with end-stage OA, based on the Kellgren-Lawrence classification.

MATERIALS AND METHODS

A comprehensive search in MEDLINE, EMBASE, Scopus, and Web of Science databases was conducted to identify randomized controlled trials (RCTs) comparing the effect of PRP injections versus other intra-articular treatments on pain and functionality. A meta-analysis was conducted using a random-effects model and the generic inverse variance method.

RESULTS

We included 31 clinical trials that reported data of 2705 subjects. Meta-analysis revealed an overall significant improvement of both pain [MD, - 1.05 (95% CI - 1.41 to - 0.68); I² = 86%; P ≤ 0.00001] and function [SMD, - 1.00 (95% CI - 1.33, to - 0.66); I² = 94%; P ≤ 0.00001], favoring PRP. Subanalysis for pain and functional improvement showed a significant pain relief in studies with 1-3 and 1-4 Kellgren-Lawrence OA stages and a significant functional improvement in studies with 1-2, 1-3 and 1-4 knee OA stages, favoring PRP.

CONCLUSION

Our results indicate that including patients with advanced knee OA does not seem to affect the outcomes of clinical trials in which the effectiveness of the PRP in knee OA is assessed.

The Epidemiology of Platelet-Rich Plasma Injections From 2010 to 2020 in a Large US Commercial Insurance Claims Database: A Recent Update

INTRODUCTION

The popularity of platelet-rich plasma (PRP) injections for the treatment of orthopaedic conditions has grown markedly. We sought to better define the trends in the usage of orthopaedic PRP injections across an insured US population over the past decade.

METHODS

The PearlDiver M91Ortho commercial administrative claims database was queried for all patients receiving PRP injections for orthopaedic conditions from 2010 through the first quarter of 2020 (Q1.2020). Trends in PRP use, reimbursement charges, demographics, joints injected, and administering physicians were assessed over time and reported as year-over-year (YOY) changes.

RESULTS

Over the study period, 14,096 unique patients had 17,759 orthopaedic PRP injections. The number of PRP injections administered had a YOY increase of 7.1% (144 injections/year, 95% confidence interval [CI] = 89 to 199, Ptrend = 0.0009). A YOY increase of 895% was observed in total nonsurgical charges ($683,974/yr, 95% CI 441,504 to 926,444, Ptrend = 0.0009). The median age of PRP recipients increased (YOY change = +0.6 years, 95% CI 0.4 to 0.8, Ptrend = 0.0005). Injections to the elbow (YOY change = -0.8%, 95% CI -0.10% to [-0.06%], Ptrend = 0.005) and foot/ankle (YOY change = -1.0%, 95% CI -1.4% to [-0.06%], Ptrend = 0.002) decreased, whereas hip (YOY change = +0.4%, 95% CI 0.2% to 0.6%, Ptrend = 0.019), knee (YOY change = +0.9%, 95% CI 0.3% to 1.2%, Ptrend = 0.016), and spine (YOY change = +0.2%, 95% CI 0.0% to 0.4%, Ptrend = 0.033) injections increased. PRP injections given by sports medicine orthopaedic surgeons (YOY change = +0.8%, 95% CI 0.6% to 1.2%, Ptrend <0.0001) increased over time, whereas those by general orthopaedic surgeons decreased (YOY change = -0.9, 95% CI -1.2 to [-0.6%], Ptrend = 0.001).

CONCLUSION

PRP injections quadrupled in prevalence from 2010 to Q1.2020, with a projected increase in annual usage in this data set of 66% by 2030. As greater evidence-based indications for PRP use are identified, more specialists and insurance providers may consider expanding their involvement in this growing field.

LEVEL OF EVIDENCE

III, retrospective cohort study.

Intra-articular injections of platelet-rich plasma decrease pain and improve functional outcomes than sham saline in patients with knee osteoarthritis

PURPOSE

To compare the long-term clinical efficacy provided by intra-articular injections of either Pure Platelet-rich Plasma (P-PRP) or sham saline to treat knee osteoarthritis (KOA).

METHODS

This prospective, parallel-group, double-blind, multi-center, sham-controlled randomized clinical trial recruited participants with KOA from orthopedic departments at nine public hospitals (five tertiary medical centers, four secondary medical units) starting January 1, 2014, with follow-up completed on February 28, 2021. Participants were randomly allocated to interventions in a 1:1 ratio. Data were analyzed from March 1, 2021, to July 15, 2021. Three sessions (1 every week) of P-PRP or sham saline injected by physicians. The primary outcome was the Western Ontario and McMaster Universities Arthritis Index (WOMAC) at 3, 6, 12, 24, 60 months of follow-up. Secondary outcomes included the International Knee Documentation Committee (IKDC) subjective score, visual analogue scale (VAS) score, intra-articular biochemical marker concentrations, cartilage volume, and adverse events. Laboratory of each hospital analyzed the content and quality of P-PRP.

RESULTS

610 participants (59% women) with KOA who received three sessions of P-PRP (n = 308, mean age 53.91 years) or sham saline (n = 302, mean age 54.51 years) injections completed the trial. The mean platelet concentration in PRP is 4.3-fold (95% confidence interval 3.6-4.5) greater than that of whole blood. Both groups showed significant improvements in IKDC, WOMAC, and VAS scores at 1 month of follow-up. However, only the P-PRP group showed a sustained improvement in clinical outcome measurements at month 24 (P < 0.001). There were statistically significant differences between the P-PRP and sham saline groups in all clinical outcome measurements at each follow-up time point (P < 0.001). The benefit of P-PRP was clinically better in terms of WOMAC-pain, WOMAC-physical function and WOMAC-total at 6, 12, 24, and 60 months of follow-up. No clinically significant differences between treatments were documented in terms of WOMAC-stiffness at any follow-up. A clinically significant difference favoring P-PRP group against saline in terms of IKDC and VAS scores was documented at 6, 12, 24 and 60 months of follow-up. At 6 months after injection, TNF-α and IL-1β levels in synovial fluid were lower in the P-PRP group (P < 0.001). Tibiofemoral cartilage volume decreased by a mean value of 1171 mm³ in the P-PRP group and 2311 mm³ in the saline group over 60 months and the difference between the group was statistically significant (intergroup difference, 1140 mm³, 95% CI - 79 to 1320 mm³; P < 0.001).

CONCLUSIONS

In this randomized clinical trial of patients with KOA, P-PRP was superior to sham saline in treating KOA. P-PRP was effective for achieving at least 24 months of symptom relief and slowing the progress of KOA, with both P-PRP and saline being comparable in safety profiles.

Effects of Intra-articular Platelet Rich Plasma on Cartilage Thickness, Clinical and Functional Outcomes in Knee Osteoarthritis

BACKGROUND

Osteoarthritis of the knee is one of the most common degenerative diseases and the fourth leading cause of years lived with disability at the global level. This study assessed the efficacy of platelet-rich plasma (PRP) in osteoarthritis of knees as to changes in cartilage thickness and clinical and functional outcomes.

METHODS

Thirty participants with Kellgren-Lawrence grade two and grade three osteoarthritis knee who satisfied the inclusion and exclusion criteria were enrolled in this prospective interventional study after taking written informed consent. Each participant received three doses of two ml intraarticular platelet-rich plasma at an interval of seven days. Clinical assessment was determined using the Visual Analogue Scale (VAS) and Knee Osteoarthritis Outcome Score (KOOS) on Day 0, Day 90, and Day 180. Cartilage thickness (femoral and trochlear cartilage) was measured pre (Day 0) and post-PRP (Day 180) under ultrasound guidance.

RESULTS

The mean VAS score for pain was 7.4 before treatment which changed to 5.3 (p= <0.0001) on Day 90 and 3.37 (p= <0.0001) on Day 180 post-PRP. The mean total KOOS was 19.16 ± 10.73 before treatment which improved to 37.42 ± 9.88 (p= <0.0001) and 49.98 ± 8.82 (p= <0.0001) at 90 days, and 180 days post-injection, respectively. The mean cartilage thickness (femoral and trochlear cartilage) improved from baseline (day 0) to final follow-up on day 180, which was statistically significant and implied cartilage repair following PRP administration.

CONCLUSION

This study supports the efficacy of PRP in the management of osteoarthritis knee by improvement in pain, joint stiffness, and activities of daily living, as well as aids in the repair and regeneration of articular cartilage.

Comparing efficacy of a single intraarticular injection of platelet-rich plasma (PRP) combined with different hyaluronans for knee osteoarthritis: a randomized-controlled clinical trial

BACKGROUND

Intraarticular plasma-rich platelet (PRP) and hyaluronic acid (HA) have each been shown to be effective for treating knee osteoarthritis (OA). Evidence supporting the combination therapy is controversial. This study aimed to investigate the efficacy of a single intraarticular PRP injection combined with different HAs in patients with knee OA.

METHODS

In this prospective randomized-controlled trial, 99 patients with Kellgren-Lawrence grade 2 knee OA with average knee pain ≥ 30 mm on a 0-100 mm pain visual analog scale (VAS) were randomized into two groups. The PRP + Artz group received a single intraarticular HA (Artz, 2.5 ml, 10 mg/ml) followed by 3 ml PRP (n = 50). The PRP + HYAJOINT Plus group received a single intraarticular cross-linked HA (HYAJOINT Plus, 3 ml, 20 mg/ml) followed by 3 ml PRP (n = 49). All patients were evaluated before and at 1, 3 and 6 months after injections. The primary outcome was the VAS pain reduction from baseline at 6 months. Secondary outcome measures included Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lequesne index, single leg stance (SLS) test and patient satisfaction.

RESULTS

Ninety-five patients were analyzed by intention-to-treat analysis. Both groups improved significantly in VAS pain, WOMAC, Lequesne index and SLS at 1, 3 and 6 months post intervention (p < 0.05). Between-group comparisons showed no significant differences at most follow-up time points, except better improvements in Lequesne index at 1 month (p = 0.003) and WOMAC-stiffness score at 6 months (p = 0.020) in the PRP + Artz group, and superiority in SLS at 1, 3 and 6 months in the PRP+ HYAJOINT Plus group (p < 0.001, p = 0.003 and p = 0.004). Additional Johnson-Neyman analyses showed that among the patients with baseline WOMAC-pain score > 8.5, WOMAC-function score > 21.7 and WOMAC-total score > 32.0, respectively, those treated with PRP + HYAJOINT Plus injections had better effects in WOMAC-pain, WOMAC-function and WOMAC-total scores than those treated with PRP + Artz at 3 months postinjection (p < 0.05). Both groups reported high satisfaction. No serious adverse events occurred during the study.

CONCLUSIONS

A single PRP injection combined with Artz or HYAJOINT Plus is effective and safe for 6 months in patients with knee OA. Both injection regimens are potential treatment options for knee OA. Further studies are needed to confirm these results.

TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov (NCT04931719), retrospectively. Date of registration 18/6/2021.

NAME OF TRIAL REGISTRY

Comparing efficacy of single PRP combined with different hyaluronans for knee osteoarthritis.

LEVEL OF EVIDENCE

Therapeutic Level 1.

The Efficacy of Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis Symptoms and Structural Changes: A Systematic Review and Meta-Analysis

BACKGROUND

Platelet-rich plasma (PRP) usage in orthopedics continues to rise, despite guidelines suggesting non-superiority to comparative cohorts. Therefore, we performed a systematic review and meta-analysis on PRP efficacy using two clinical assessments: (1) Visual Analog Scale and (2) Western Ontario and McMaster Universities Osteoarthritis Index. We assessed consistency and clinical relevancy by determining study heterogeneity (eg, sample sizes, ages, body mass index, arthritic severities, etc.). Comparative cohorts were: (A) hyaluronic acid (HA); (B) corticosteroid (CS); (C) normal saline (NS); and (D) exercise therapy. We performed sub-analyses of structural changes assessed on ultrasound, radiograph, or magnetic resonance imaging .

METHODS

We utilized PubMed, Cochrane Library, and Embase databases up to December 1, 2021, according to Preferred Reporting Items for Systematic-Reviews and Meta-Analyses guidelines. Twenty-four studies met criteria, with comparisons to: HA (n = 11); CS (n = 6); NS (n = 5); and exercise therapy (n = 3). Seven studies assessed structural changes. Evaluations utilized a methodological scoring system. I² statistics and forest plots pooled analyses and delineated study results.

RESULTS

PRP led to Visual Analog Scale and Western Ontario and McMaster Universities Osteoarthritis Index improvements in most studies when compared to HA, CS, and NS (P ≤ .05). Comparison to exercise therapy resulted in inconclusive findings (P ≥ .05). However, substantial heterogeneity (I² ≥ 76%) was reported due to study variability. No differences were found when assessing structural changes or cartilage thickness by magnetic resonance imaging (standardized mean difference -0.01 [-0.19, 0.18], P = .91).

CONCLUSIONS

PRP may be associated with pain and functional improvements but was not clinically relevant (inconsistent study- and patient-metrics). In addition, PRP did not confer superiority when assessing knee-related structural changes.

Intra Articular Injection of Autologous Microfat and Platelets-Rich Plasma in the Treatment of Wrist Osteoarthritis: A Pilot Study

No injection treatment has been proven to be effective in wrist osteoarthritis. When conservative measures fail, its management involves invasive surgery. Emergence of biotherapies based on adipose derived stem cells (ADSC) offers promising treatments for chondral degenerative diseases. Microfat (MF) and platelets-rich plasma (PRP) mixture, rich in growth factors and ADSC could be a minimally invasive injectable option in the treatment of wrist osteoarthritis. The aim of this uncontrolled prospective study was to evaluate the safety of a 4 mL autologous MF-PRP intra-articular injection, performed under local anesthesia. The secondary purpose was to describe the clinical and MRI results at 12 months of follow-up. Patients' data collected were: occurrence of adverse effects, Visual analog scale (VAS), Disabilities of the Arm, Shoulder and Hand score (DASH) and Patient-Rated Wrist Evaluation (PRWE) scores, wrist strength, wrist range of motion and 5-level satisfaction scale. No serious adverse event was recorded. A statistically significant decrease in pain, DASH, PRWE and force was observed at each follow-up. Our preliminary results suggest that intra-articular autologous MF and PRP injection may be a new therapeutic strategy for wrist osteoarthritis resistant to medical symptomatic treatment prior to surgical interventions.

A prospective cohort study: platelet-rich plasma combined with carpal tunnel release treating carpal tunnel syndrome

Background

PRP injection was proved to promote the health condition of individuals with mild to moderate Carpal Tunnel Syndrome (CTS). However, carpal tunnel release (CTR) was still a necessary treatment for individuals with moderate and severe CTS.

Methods

To explore whether adjuvant PRP treatment would improve the prognosis while using CTR, we included 82 patients in this study. Preoperative and postoperative visual analog scale (VAS), Boston carpal tunnel syndrome questionnaire-symptom severity scale (BCTQ-SSS), Boston carpal tunnel syndrome questionnaire-functional status scale (BCTQ-FSS), and grip strength were used to examine the patient's symptoms and function.

Results

CTR combined with PRP treatment improved the VAS (1.9 ± 0.5 versus 1.4 ± 0.4, P < .05), BCTQ-SSS (1.8 ± 0.4versus 1.5 ± 0.3, P < .05) and BCTQ-FSS (1.8 ± 0.5 versus 1.4 ± 0.6, P < .05) in patients with moderate symptoms within one month after surgery. At the same time, it does not show any advantages in treating individuals with severe carpal tunnel syndrome.

Conclusions

PRP does not affect long-term prognosis while increasing the surgery cost. To conclude, PRP as an adjuvant treatment of CTR has limited effect. Considering the additional financial burden on patients, CTR combined with PRP should be cautious in CTS treatment.

Current State of Platelet-Rich Plasma and Cell-Based Therapies for the Treatment of Osteoarthritis and Tendon and Ligament Injuries

➤

Orthobiologics encompass numerous substances that are naturally found in the human body including platelet-rich plasma (PRP), isolated growth factors, and cell therapy approaches to theoretically optimize and improve the healing of cartilage, fractures, and injured muscles, tendons, and ligaments.

➤

PRP is an autologous derivative of whole blood generated by centrifugation and is perhaps the most widely used orthobiologic treatment modality. Despite a vast amount of literature on its use in osteoarthritis as well as in tendon and ligament pathology, clinical efficacy results remain mixed, partly as a result of insufficient reporting of experimental details or exact compositions of PRP formulations used.

➤

Mesenchymal stromal cells (MSCs) can be isolated from a variety of tissues, with the most common being bone marrow aspirate concentrate. Similar to PRP, clinical results in orthopaedics with MSCs have been highly variable, with the quality and concentration of MSCs being highly contingent on the site of procurement and the techniques of harvesting and preparation.

➤

Advances in novel orthobiologics, therapeutic targets, and customized orthobiologic therapy will undoubtedly continue to burgeon, with some early promising results from studies targeting fibrosis and senescence.

Efficacy of Oxygen-Ozone Therapy and Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis: A Meta-analysis and Systematic Review

Context

This systematic review and meta-analysis evaluated the effect of the intra-articular injection of platelet-rich plasma (PRP) and oxygen-ozone therapy and provided an evidence-based methodology to treat KOA.

Method

Databases, including Cochrane Library, PubMed, and EMBASE, were searched. The retrieval period was before 2021. Two reviewers performed the process of screening and data extraction. Mean differences were calculated [95% confidence interval (CI)] with an inverse-variance method and fixed effect model. Meta-analysis was performed using the latest version of STATA version 16.

Results

A total of 12 studies out of 769 articles were evaluated. The mean difference of visual analog scale score between ozone and control groups in the first month after injection was -0.02 (MD, -0.02; 95% CI: -0.32, 0.28; P < 0.05). Mean differences of WOMAC pain, stiffness, and physical function score between baseline and after PRP were -3.53 (MD: -3.53; 95% CI: -4.04, -3.02; P = 0.00), -0.60 (MD: -0.60; 95% CI: -4.0 - 0.864, -0.34; P = 0.00), and -5.96 (MD: -5.96; 95% CI: -7.83, -4.09; P = 0.00).

Conclusions

Our results showed that to treat knee osteoarthritis, using PRP for a longer period of 6 - 12 months after the intervention shows better clinical results, while oxygen-ozone therapy has short-term results.

The efficacy of transcatheter arterial embolization for knee pain on patients with knee osteoarthritis: A case series

BACKGROUND

Knee osteoarthritis (OA) is accompanied by inflammation and angiogenesis. Modifying angiogenesis through transcatheter arterial embolization (TAE) can be a potential treatment for knee OA.

OBJECTIVE

We subjected five OA knees in three patients to TAE and report the results of our post-treatment observations.

CASE DESCRIPTION

Three patients that had experienced knee pain for a minimum of one year prior to the study, and whose pain had persisted despite conservative treatment, were included in this study. Patients more often chose conservative treatment over surgical treatment. Pain and functional scales were evaluated before, immediately, and 1 month after TAE using the Numeric Rating Scale (NRS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). TAE was performed by an experienced interventional radiologist. The average values of NRS evaluated before and after 5 TAEs were 5.2 before TAE, 3 immediately after TAE, and 3.6 after 1 month of TAE, and the average values of WOMAC were 52, 38.4, and 36.4, respectively. There were no major adverse effects.

CONCLUSION

The examined cases support the conclusion that TAE is an effective treatment for patients with knee OA. Substantial pain relief and WOMAC improvement were observed both immediately and one month after TAE.

A Net Meta-Analysis of the Effectiveness of Different Types of Dressings in the Treatment of Diabetic Foot

Objective

This is an analysis of the impact of a new dressing commonly used to treat diabetic foot (DFU).

Methods

Chinese and English databases were searched to collect clinical randomized controlled studies (RCTs) of various types of dressings for the treatment of DFU, and the healing rates of the different dressings were combined by reticulation meta-analysis.

Results

The aggregate of the 36 RCTs included in this study analysed the healing rates of nine dressings: conventional dressing, alginate dressing, chitosan dressing, hyaluronic acid dressing, platelet-rich plasma dressing, amniotic membrane dressing, honey dressing, human recombinant growth factor dressing, and silver ionomer dressing.

Conclusion

Hyaluronic acid dressing, amniotic membrane dressing, honey dressing, and platelet-rich plasma dressing are the ideal materials for topical treatment of DFU.

The effectiveness of leucocyte-poor platelet-rich plasma injections on symptomatic early osteoarthritis of the knee: the PEAK randomized controlled trial

AIMS

Platelet-rich plasma (PRP) intra-articular injections may provide a simple and minimally invasive treatment for early-stage knee osteoarthritis (OA). This has led to an increase in its adoption as a treatment for knee OA, although there is uncertainty about its efficacy and benefit. We hypothesized that patients with early-stage symptomatic knee OA who receive multiple PRP injections will have better clinical outcomes than those receiving single PRP or placebo injections.

METHODS

A double-blinded, randomized placebo-controlled trial was performed with three groups receiving either placebo injections (Normal Saline), one PRP injection followed by two placebo injections, or three PRP injections. Each injection was given one week apart. Outcomes were prospectively collected prior to intervention and then at six weeks, three months, six months, and 12 months post-intervention. Primary outcome measures were Knee Injury and Osteoarthritis Outcome Score (KOOS) and EuroQol five-dimension five-level index (EQ-5D-5L). Secondary outcomes included visual analogue scale for pain and patient subjective assessment of the injections.

RESULTS

A total of 102 patients were recruited. The follow-up period was 12 months, at intervals of six weeks, 12 weeks, six months, and 12 months. KOOS-Total significantly improved in all groups at these time intervals compared to pre-injection. There was an improvement in EQ-5D-5L index scores in saline and single injection groups, but not in the multiple injection group. Comparison of treatment groups showed no additional beneficial effect of single or multiple PRP injections above that displayed in the saline injection group. Subjective patient satisfaction and recommendation of treatment received demonstrated a similar pattern in all the groups. There was no indication of superiority of either single or multiple PRP injections compared to saline injections.

CONCLUSION

There is no evidence that single or multiple PRP had any additional beneficial effect compared to saline injection up to 12 months, follow-up after treatment of early stage symptomatic OA of the knee. Cite this article: Bone Joint J 2022;104-B(6):663-671.

Bibliometric analysis of the top 50 highly cited articles on platelet-rich plasma in osteoarthritis and tendinopathy

The primary goal of this study was to compile the top 50 most cited articles on the use of platelet-rich plasma (PRP). A search of relevant studies was performed in accordance with the PRISMA guidelines in Web of Science. The top 25 most cited articles in osteoarthritis and tendinopathy were then compiled and evaluated. Level 1 evidence articles constituted the majority of the studies (64%) and were more likely to have a higher citation density. Altmetric data was highest for level 1 systematic reviews. Of the articles that report a positive outcome for PRP, 13% (2/16) had low risk of bias. This study defines the most cited and influential publications regarding PRP to further research in this area.

Thermal Oscillation Changes the Liquid-Form Autologous Platelet-Rich Plasma into Paste-Like Form

Objectives

The texture of the autologous platelet-rich plasma (PRP) that is used in treating degenerative joint diseases such as knee osteoarthritis (OA) is usually in liquid form. However, the turnover rate of protein metabolism in the knee synovial fluid (SF) is less than one hour. This study examined the feasibility of the thermal oscillation technique in converting the liquid-form PRP into an injectable viscous paste-like PRP that may delay the degradation of PRP and continuously release growth factors in the knee joint for a longer period of time.

Methods

This study was conducted in the rehabilitation department of a tertiary hospital. A total of 10 elderly patients with an average age of greater than 65 years and diagnosed with moderate degree of knee OA were recruited. The RegenPRP (RegenLab, Le Mont-sur-Lausanne, Switzerland) test tube chamber was used for PRP generation. A total of 60 milliliters (mL) of blood was drawn from each patient. 10 mL of blood was injected into each PRP test tube chamber. As a result, a total of 6 test tube chambers were obtained and each chamber was centrifuged for 15 minutes. Approximately 5 mL of PRP supernatant (the liquid-form end product) was aspirated and sent for thermal oscillation treatment. Five temperatures were tested: 55, 65, 75, 85, and 95 degrees Celsius. Oscillation was set at 200 revolutions per minute (rpm) for 15 minutes. The enzyme-linked immunosorbent assay (ELISA) was applied in measuring the concentration of platelet-derived growth factor (PDGF) in picogram/milliliter (pg/mL). Repeated measures ANOVA followed by the Bonferroni post hoc test was used to compare the PDGF concentrations between each testing condition.

Results

Under 75 degrees Celsius of heating, the resultant paste-like PRP end product had the highest concentration of PDGF in picograms per milliliter (pg/mL) as compared with other heating conditions (p < 0.05). The viscosity of the paste-like PRP was measured to be 70,000 centipoise (cP), which is similar to the viscosity of a toothpaste. The paste-like PRP end product was able to release PDGF continuously for about 14 days, with the highest concentration achieved on the 8^th day with an average of 35646 ± 2499 pg/mL. In nonthermally treated liquid-form PRP sample, the highest number of PRP was observed on the 4^th day with an average value of 8444 ± 831 pg/mL. Under the heating conditions of 55 and 95 degrees Celsius, the highest concentration of PDGF was observed on the 5^th day (13346 ± 764 pg/mL and 3440 ± 303 pg/mL, respectively). Under the heating conditions of 65 and 85 degrees Celsius, the highest concentration of PDGF was observed on the 7^th day (15468 ± 744 pg/mL and 20432 ± 1118 pg/mL, respectively).

Conclusion

Through thermal oscillation, liquid-form PRP can be converted to paste-like PRP end product with a viscosity similar to that of a toothpaste. The best heating condition was discovered to be 75 degrees Celsius. The paste-like PRP was able to release PDGF continuously for about 2 weeks, with the highest concentration obtained on the 8^th day. The findings in this study suggested that paste-like PRP may be a viable option in treating degenerative knee joint diseases.

VEGF-attenuated platelet-rich plasma improves therapeutic effect on cartilage repair

Autologous platelet-rich plasma (PRP) has gained popularity as a less invasive treatment for various musculoskeletal tissue injuries and conditions due to its favorable safety profile, minimal manipulation and cost-effectiveness. Although PRP treatment has been clinically used for the treatment of osteoarthritis (OA) and damaged cartilage, evidence on therapeutic efficacy has been inconsistent, which calls for a methodology to achieve consistent and improved treatment outcomes. Given that PRP contains numerous proteins, we hypothesized that attenuation of a growth factor known to be detrimental to the healing tissue would enhance efficacy of PRP treatment. Considering that VEGF-mediated angiogenesis inhibits the repair of articular cartilage, we developed VEGF-attenuated PRP by sequestering VEGF in PRP using VEGF-binding microspheres. We demonstrated that VEGF attenuation in PRP did not inhibit the effect of PRP on chondrogenic differentiation of stem cells in vitro. In addition, healing of rat OA cartilage was significantly improved after treatment with VEGF-attenuated PRP when compared to the PRP treatment group or PBS control group. We expect that attenuation of unwanted biological activity using growth factor-binding microspheres could provide a new PRP customization method broadly applicable to various tissue repair processes.

Management of Knee Osteoarthritis: What Internists Need to Know

Knee osteoarthritis (OA) is a common and morbid condition. No disease-modifying therapies exist; hence the goals of current treatment are to palliate pain and to retain function. OA pain is significantly influenced by the placebo effect. Nonpharmacologic interventions are essential and have been shown to improve outcomes. Canes, unloading braces, and therapeutic heating/cooling may be valuable. Pharmacotherapy options include topical and oral nonsteroidal anti-inflammatory drugs, duloxetine, and periodic intra-articular glucocorticoids and hyaluronans. Opioids, intra-articular stem cells, and platelet-rich plasma are not recommended. Novel targets such as nerve growth factor are under investigation and may be approved soon for OA pain.

The use of intra-articular platelet rich plasma for the symptomatic management of osteoarthritis of the knee: a pilot study

BACKGROUND

Osteoarthritis of the knee is a chronic inflammatory condition resulting in significant patient disability, with intra-articular platelet rich plasma (PRP) injections having shown potential to improve symptomatic outcomes. This retrospective cohort pilot study aimed to observe whether PRP injections were beneficial in the symptomatic management of knee osteoarthritis in an Australian population, based on patient reported outcomes. An additional aim was to observe for an association between the number of injections and patient characteristics, such as body mass index, age, sex and radiologically determined severity of the disease.

METHODS

The cohort was drawn from those who attended Ballarat Orthopaedic and Sports Medicine for PRP injections and who had completed the appropriate pre- and post-injection Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire. WOMAC scores were analysed to observe for any difference following a course of PRP injections.

RESULTS

The data suggest that the use of PRP improved patient reported WOMAC scores. Additionally, it was shown that two injections had a greater effect than one injection, with a third injection providing no further benefit. Finally, there was an association with lower WOMAC scores post PRP therapy amongst male participants compared to female participants.

CONCLUSION

These results suggest two PRP injections are optimal for the symptomatic management of knee osteoarthritis, identifying a need for further prospective research in this Australian population.

Platelet-rich plasma (PRP) augmentation does not result in more favourable outcomes in arthroscopic meniscal repair: a meta-analysis

Background

The efficacy and safety of platelet-rich plasma (PRP) augmentation for arthroscopic meniscal repair is controversial. This meta-analysis compared arthroscopic meniscal repair performed in isolation or augmented with PRP.

Methods

The present study was conducted according to PRISMA 2020 guidelines. Pubmed, Web of Science, Google Scholar and Embase were accessed in August 2021. All the clinical trials which compared arthroscopic meniscal repair performed in isolation or augmented with PRP were included.

Results

Eight hundred thirty-seven patients were included: 38% (318 of 837 patients) were women; the mean age of the patients was 35.6 (range, 20.8–64.3) years; the mean follow-up was 26.2 (range, 6–54) months. Similarity was found in analogue scale (VAS) (P = 0.5) and Lysholm (P = 0.9), and International Knee Documentation Committee (IKDC) scores (P = 0.9). Similarity was found in the rate of failure (P = 0.4) and rate of revision (P = 0.07).

Conclusion

The current published scientific evidence does not support PRP augmentation for arthroscopic meniscal repair.

Conservative Treatment of the Fifth Metatarsal Bone Fractures in Professional Football Players Using Platelet-Rich Plasma

Injuries of the metatarsal bones in football are relatively rare and in most cases are localized in the fifth metatarsal. The gold standard of the diagnosis of fractures in this area can be X-rays, which in most cases allows verifying the diagnosis. The treatment tactics depend on the localization of the fracture according to Lawrence and Botte's classification: 3 zones of localization are distinguished. Fractures located in zones 2 and 3 belong to a high-risk group due to delayed consolidation and nonunion and therefore athletes are most often treated with osteosynthesis using intramedullary screws. The minimal recovery time for this type of treatment is at least 8 weeks. This report describes 7 cases of the fifth metatarsal bone fractures, located in zones 2 and 3 in professional football players who were treated with an immobilization boot, cryotherapy, nutritional supplements of calcium and vitamin D, and local injections of platelet-rich plasma, which contains numerous growth factors. The deadline for returning to regular training activities was 43 to 50 days, and there was no relapse of damage within 6 months of follow-up.Levels of Evidence: Level of evidence 4: case report study.

A single intraarticular platelet-rich plasma improves pain and function for patients with early knee osteoarthritis: Analyses by radiographic severity and age

BACKGROUND

Most studies use platelet-rich plasma (PRP) requiring multiple intraarticular injections for knee osteoarthritis (OA).

OBJECTIVE

To investigate the efficacy of a single intraarticular PRP injection for patients with early knee OA and consider subgroup analyses of radiographic severity and age, respectively.

METHODS

Forty-one patients with knee OA (Kellgren-Lawrence grade 1-2) received a single PRP injection into the target knee and were assessed at baseline and 1, 3, and 6 months postinjection. The primary outcome was the mean change from baseline in the visual analog scale (VAS) pain (0-100 mm) at 6 months postinjection. Secondary outcomes included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lequesne index, single leg stance test (SLS), use of rescue analgesics and patients' satisfaction.

RESULTS

Thirty-eight patients completed the study. The mean pain VAS decreased significantly from 45.6 ± 13.0 mm at baseline to 16.9 ± 13.4 mm, 14.0 ± 13.1 mm and 15.5 ± 14.0 mm at 1, 3 and 6-month follow-ups (p< 0.001 for all). Significant improvements in WOMAC, Lequesne index, SLS and consumption of analgesics from baseline (p< 0.001 for all) were noted at each follow-up. Patients' satisfaction was high. No serious adverse events occurred. Subgroup analyses revealed that patients with grade 1 OA showed significantly greater VAS pain reduction at 3 months (p= 0.006) and 6 months (p= 0.005) than patients with grade 2 OA. The older-age group (age > 60) showed significantly greater improvements in VAS pain, WOMAC function subscale scores and total scores at 6-month postinjection, compared with the younger age-group (age ≤ 60). The younger-age group reported better satisfaction at 1 and 3-month postinjection.

CONCLUSIONS

One injection of PRP improved pain and function for 6 months for patients with early knee OA. This study supports putting the one-injection regimen into clinical practice. Further research is needed for more definite conclusions.

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.

Efficacy of Intra-Articular Injection of Platelet-Rich Plasma Combined with Mesenchymal Stem Cells in the Treatment of Knee Osteoarthritis: A Systematic Review and Meta-Analysis

OBJECTIVE

This study systematically evaluated the effect of intra-articular injection of platelet-rich plasma (PRP) and mesenchymal stem cells (MSC) on knee osteoarthritis (KOA).

METHODS

Randomized controlled trials (RCTs) of PRP combined with MSC in the treatment of KOA were collected from PubMed, Cochrane Library, Web of Science, Wiley online library, CNKI, and Wanfang databases from inception to July 30, 2022. Two researchers read and screened the literature to extract the data, respectively. After conducting a risk-of-bias assessment of included data, RevMan 5.3 software was used for meta-analysis. The Cochrane Handbook risk-of-bias assessment tool was used to evaluate the included literature.

RESULTS

A total of 9 papers with 480 KOA patients were included in this study. Significant differences in terms of visual analogue scale (VAS) score (MD = -1.10, 95% CI -1.91 to -0.29), P = 0.008) and knee injury and osteoarthritis outcome score (KOOS) (MD = 4.56, 95% CI 0.54-8.58, P = 0.050) were noted between the 2 groups. Subgroup analysis found that MD = 1.66 in KOOS-pain-1 group (95% CI (0.10, 3.22), P = 0.040), which is significant. The MD for KOOS total score and IKDC scores between the two groups was MD = 6.31 (95% CI 2.73-9.88, P = 0.0005) and MD = 3.05 (95% CI -7.09-13.20, P = 0.56), respectively.

CONCLUSION

The results of this study provide a theoretical basis for the clinical treatment of KOA with PRP combined with MSC.

Platelet-Rich Plasma for Knee Osteoarthritis: Internet Marketing and Patient Education-An Appraisal of Content for Websites with the Greatest Search Engine Visibility

OBJECTIVE

The internet is increasingly being used as a resource for health-related information by the general public. We sought to establish the authorship, content, and accuracy of the information available online regarding platelet-rich plasma (PRP) therapy for knee osteoarthritis.

DESIGN

Top 200 search results from each of the 3 leading search engines available online (Google, Yahoo!, Bing) were screened, and 181 websites were finally reviewed for content with emphasis on specific claims, comparing between websites authored by private physicians/groups and other authorship types.

RESULTS

Nearly 80% of the websites claimed that PRP injections for osteoarthritis of the knee improve patients' pain. A total of 42.8% of the private websites and 27.6% of nonprivate websites have stated that the procedure can delay or eliminate the need for future surgery. Costs were only mentioned by few (11.6%), and mainly by the nonprivate websites. Both website groups were unlikely to mention that PRP therapy is not the treatment of choice for end-stage knee osteoarthritis (7.9% of private and 17.2% of the nonprivate sites), or to state that patients with less advanced disease may benefit more from the treatment (11.8% and 20.6%, respectively). Private websites were less likely to refer to peer-reviewed literature (18.4% vs. 41.4%) and were more than 3 times less likely to mention lack of adequate evidence (13.2% vs. 48.2%).

CONCLUSIONS

Patients seeking online information regarding PRP therapy are vulnerable to websites presenting a narrow viewpoint of this treatment modality, putting emphasis on unsubstantiated benefits while disregarding potential drawbacks and concerns.