Intra-articular Autologous Conditioned Plasma Injections Provide Safe and Efficacious Treatment for Knee Osteoarthritis: An FDA-Sanctioned, Randomized, Double-blind, Placebo-controlled Clinical Trial

Intra-articular injection with Autologous Conditioned Plasma does not lead to a clinically relevant improvement of knee osteoarthritis: a prospective case series of 140 patients with 1-year follow-up

Background and purpose - Platelet-rich plasma (PRP) is broadly used in the treatment of knee osteoarthritis, but clinical outcomes are highly variable. We evaluated the effectiveness of intra-articular injections with Autologous Conditioned Plasma (ACP), a commercially available form of platelet-rich plasma, in a tertiary referral center. Second, we aimed to identify which patient factors are associated with clinical outcome. Patients and methods - 140 patients (158 knees) with knee osteoarthritis (Kellgren and Lawrence grade 0-4) were treated with 3 intra-articular injections of ACP. The Knee Injury and Osteoarthritis Outcome Score (KOOS), pain (Numeric Rating Scale; NRS), and general health (EuroQol 5 Dimensions; EQ5D) were assessed at baseline and 3, 6, and 12 months' follow-up. The effect of sex, age, BMI, Kellgren and Lawrence grade, history of knee trauma, and baseline KOOS on clinical outcome at 6 and 12 months was determined using linear regression. Results - Mean KOOS increased from 37 at baseline to 44 at 3 months, 45 at 6 months, and 43 at 12 months' follow-up. Mean NRS-pain decreased from 6.2 at baseline to 5.3 at 3 months, 5.2 at 6 months, and 5.3 at 12 months. EQ5D did not change significantly. There were no predictors of clinical outcome. Interpretation - ACP does not lead to a clinically relevant improvement (exceeding the minimal clinically important difference) in patients suffering from knee osteoarthritis. None of the investigated factors predicts clinical outcome.

Are PROMs used adequately in sports research? An analysis of 54 randomized controlled trials with PROMs as endpoint

Deviations from adequate use and reporting of PROMs may be problematic and misleading. The aim of this study was to investigate the extent of such problems in randomized clinical trials (RCTs). RCTs involving sports medicine research that used PROMs as primary outcomes were identified in 13 preselected journals. The articles were reviewed for nine potential problems related to how the PROM was used and how the data had been reported. The potential problems were as follows: aggregating subscale scores; combining patient-reported scores with physical, clinical, or para-clinical measures; using a PROM to diagnose or evaluate the individual patient; using a PROM for one leg or arm; selectively excluding domains or items; constructing a PROM for the specific occasion; mixing PROM formats (ie, digital, paper, telephone, e-mail, in person); ambiguous instructions for how the PROM should be completed; and recall bias. As covariates, we registered journal impact factor, year of publication, and existence of a registered protocol. In 29 (53.7%) of 54 identified RCTs, at least one potential problem was identified, the most common being aggregation of domain scores. This was not different with a published protocol or dependent on journal rankings, except for exclusion of domains, which was most common in high-ranking journals. Aggregation of domain scores was significantly less common in recently published articles compared with older articles (P = .03). Potential problematic use of PROMs and reporting of PROM data are common in RCTs, also in high-ranking journals, but less so in more recent articles.

Efficacy of Autologous Conditioned Serum (ACS), Platelet-Rich Plasma (PRP), Hyaluronic Acid (HA) and Steroid for Early Osteoarthritis Knee: A Comparative Analysis

BACKGROUND

Intra-articular injection therapy constituting corticosteroids, viscosupplements and blood-derived products are considered to have a key role in non-operative management of osteoarthritis knee. While corticosteroids and viscosupplements have proven short-term efficacy in early osteoarthritis; orthobiologics are gaining increased attention in osteoarthritis management. The aim of present study was thus to compare two commonly used biologics (platelet-rich plasma/PRP and autologous conditioned serum/ACS) to each other and to established therapies.

METHODS

After required institutional clearances, all patients presenting with early primary osteoarthritis knee who had failed initial conservative management and received only unilateral knee injection were included. Patients in the PRP group were compared to the other groups (comprising the HA/hyaluronic acid group, steroid group, and a matched cohort who had been administered ACS for the same indication earlier). Clinical outcome was evaluated using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire and Visual Analogue scale (VAS) pre-injection and at 6 months.

RESULTS

ACS and PRP did not have any significant difference in terms of either WOMAC score (p = 0.154) or VAS score at 6 months (p = 0.850). The scores for both these orthobiologics were better than the control groups (HA group and Steroid group). Between the two control groups, HA group had better VAS scores as compared to the Steroid group (p = 0.008).

CONCLUSION

The clinical outcomes following intra-articular injection of ACS and PRP are better than controls (HA and steroid), but a difference between the two orthobiologics could not be demonstrated.

LEVEL OF EVIDENCE

3b.

Phase II multicenter randomized controlled clinical trial on the efficacy of intra-articular injection of autologous bone marrow mesenchymal stem cells with platelet rich plasma for the treatment of knee osteoarthritis

Background

Mesenchymal stromal cells are a safe and promising option to treat knee osteoarthritis as previously demonstrated in different clinical trials. However, their efficacy, optimal dose and addition of adjuvants must be determined. Here, we evaluated the clinical effects of a dose of 100 × 10⁶ bone marrow mesenchymal stromal cells (BM-MSCs) in combination with Platelet Rich Plasma (PRGF®) as adjuvant in a randomized clinical trial.

Methods

A phase II, multicenter, randomized clinical trial with active control was conducted. Sixty patients diagnosed with knee OA were randomly assigned to 3 weekly doses of PRGF® or intraarticular administration of 100 × 10⁶ cultured autologous BM-MSCs plus PRGF®. Patients were followed up for 12 months, and pain and function were assessed using VAS and WOMAC and by measuring the knee range of motion range. X-ray and magnetic resonance imaging analyses were performed to analyze joint damage.

Results

No adverse effects were reported after BM-MSC administration or during follow-up. According to VAS, the mean value (SD) for PRGF® and BM-MSC with PRGF® went from 5 (1.8) to 4.5 (2.2) (p = 0.389) and from 5.3 (1.9) to 3.5 (2.5) (p = 0.01), respectively at 12 months. In WOMAC, the mean (SD) baseline and 12-month overall WOMAC scores in patients treated with PRGF® was 31.9 (16.2) and 22.3 (15.8) respectively (p = 0.002) while that for patients treated with BM-MSC plus PRGF® was 33.4 (18.7) and 23.0 (16.6) (p = 0.053). Although statistical significances between groups have been not detected, only patients being treated with BM-MSC plus PRGF® could be considered as a OA treatment responders following OARSI criteria. X-ray and MRI (WORMS protocol) revealed no changes in knee joint space width or joint damage.

Conclusions

Treatment with BM-MSC associated with PRGF® was shown to be a viable therapeutic option for osteoarthritis of the knee, with clinical improvement at the end of follow-up. Further phase III clinical trials would be necessary to confirm the efficacy.

Trial registration Clinical Trials.gov identifier NCT02365142. Nº EudraCT: 2011-006036-23

The Cost-Effectiveness of Platelet-Rich Plasma Injections for Knee Osteoarthritis: A Markov Decision Analysis

BACKGROUND

Use of platelet-rich-plasma (PRP) injections for treating knee osteoarthritis has increased over the past decade. We used cost-effectiveness analysis to evaluate the value of PRP in delaying the need for total knee arthroplasty (TKA).

METHODS

We developed a Markov model to analyze the baseline case: a 55-year-old patient with Kellgren-Lawrence grade-II or III knee osteoarthritis undergoing a series of 3 PRP injections with a 1-year delay to TKA versus a TKA from the outset. Both health-care payer and societal perspectives were included. Transition probabilities were derived from systematic review of 72 studies, quality-of-life (QOL) values from the Tufts University Cost-Effectiveness Analysis Registry, and individual costs from Medicare reimbursement schedules. Primary outcome measures were total costs and quality-adjusted life years (QALYs), organized into incremental cost-effectiveness ratios (ICERs) and evaluated against willingness-to-pay thresholds of $50,000 and $100,000. One and 2-way sensitivity analyses were performed as well as a probabilistic analysis varying PRP-injection cost, TKA delay intervals, and TKA outcomes over 10,000 different simulations.

RESULTS

From a health-care payer perspective, PRP resulted in 14.55 QALYs compared with 14.63 for TKA from the outset, with total health-care costs of $26,619 and $26,235, respectively. TKA from the outset produced a higher number of QALYs at a lower cost, so it dominated. From a societal perspective, PRP cost $49,090 versus $49,424 for TKA from the outset. The ICER for TKA from the outset was $4,175 per QALY, below the $50,000 willingness-to-pay threshold. Assuming the $728 published cost of a PRP injection, no delay time that was <10 years produced a cost-effective course. When the QOL value was increased from the published value of 0.788 to >0.89, PRP therapy was cost-effective with even a 1-year delay to TKA.

CONCLUSIONS

When considering direct and unpaid indirect costs, PRP injections are not cost-effective. The primary factor preventing PRP from being cost-effective is not the price per injection but rather a lack of established clinical efficacy in relieving pain and improving function and in delaying TKA. PRP may have value for higher-risk patients with high perioperative complication rates, higher TKA revision rates, or poorer postoperative outcomes.

LEVEL OF EVIDENCE

Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Autologous Protein Solution Injections for the Treatment of Knee Osteoarthritis: 3-Year Results

BACKGROUND

Blood derivative injections have been recently proposed to address osteoarthritis (OA) with overall positive results, although long-term data on their efficacy are lacking. A novel blood derivative has been developed to concentrate growth factors and antagonists of inflammatory cytokines and shown promising early findings.

PURPOSE

To investigate if the positive effects of a single intra-articular injection of autologous protein solution (APS) in patients affected by knee OA-previously documented at 1 year in a multicenter double-blind randomized saline-controlled trial-last up to 3 years.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 46 patients with Kellgren-Lawrence 2 or 3 knee OA were randomized into 2 groups: 1 ultrasound-guided APS injection (n = 31) or 1 saline injection (n = 15). At 1 year, the saline group was allowed to cross over. Patients were re-evaluated at 24 and 36 months through the visual analog scale for pain (VAS), Western Ontario and McMaster Universities Osteoarthritis Index Likert 3.1 (WOMAC LK 3.1), Knee injury and Osteoarthritis Outcome Score (KOOS), 36-Item Short Form Health Survey (SF-36), and Outcome Measures in Rheumatology-Osteoarthritis Research Society International (OMERACT-OARSI) responder rate. Magnetic resonance imaging evaluation was performed with the MRI Osteoarthritis Knee Score (MOAKS) before and at 24 months after treatment, and radiographs were assessed per Kellgren-Lawrence before and annually after treatment.

RESULTS

In the APS cohort, WOMAC pain improved from 11.5 ± 2.4 (mean ± SD) to 4.3 ± 4.0 at 1 year and to 5.7 ± 5.0 at 3 years (P < .0001 vs baseline). The APS cohort also showed a statistically significant improvement in its KOOS pain score from 39.4 ± 13.1 to 70.6 ± 21.5 at 1 year and to 64.1 ± 24.6 at 3 years (P < .0001 vs baseline) and VAS pain scores from 5.5 ± 2.2 to 2.6 ± 2.5 at 1 year and to 3.4 ± 2.9 at 3 years (P = .0184 vs baseline). VAS pain score significantly worsened from 12 to 36 months (P = .0411). All patients in the saline group decided to cross over to APS, and their final scores were better than baseline, although not significantly better than at the crossover point. Overall, 7 of 26 (26.9%) APS cases and 4 of 14 (28.6%) crossover cases were considered failures as patients underwent further injective treatments or surgical procedures between the 12- and 36-month follow-up. MOAKS findings showed no statistically significant differences. Patients with better cartilage had greater WOMAC pain improvement when their baseline scores were worse, whereas the trend was reversed for patients with cartilage loss at baseline.

CONCLUSION

Intra-articular use of APS for mild to moderate knee OA was safe, and significant pain improvement was documented 3 years after a single injection. Patients with better cartilage status seem to respond better than patients with more cartilage loss, with more clinical improvement even when starting from more painful conditions.

REGISTRATION

NCT02138890 (ClinicalTrials.gov identifier).

Lack of standardization among clinical trials of injection therapies for knee osteoarthritis: a systematic review

Purpose: Osteoarthritis (OA) of the knee is a debilitating, expensive, and prevalent disease, and interest in the non-surgical management of knee OA has grown recently. Our objective was to systematically assess the level of heterogeneity among all clinical trials and published studies regarding injections for knee osteoarthritis, in terms of treatment of interest, outcomes evaluated, and time points of outcome assessment. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were utilized to review all published studies and publically available clinical trials from 1 January 2013 to 3 May 2019evaluating intra-articular injections to treat knee OA. Their treatment group and specifics of methodology were scrutinized and compared. Results: 84 published studies and 114 clinical trials were included. Within the 84 published studies, the most common injection treatment studied was hyaluronic acid [N = 22; 26.2%]. In total, 29 different injection treatment groups were utilized. The most common time point for patient evaluation post-injection was 6 months (N = 33 studies; 50.0%), and ranged from 1 week (N = 9 studies; 13.6%) to 7 years (N = 1 study; 1.5%). The most common patient-reported outcome (PRO) measure assessed in the included studies was Western Ontario and McMaster's University Osteoarthritis Index (WOMAC) [N = 44 studies; 66.7%]. For the 114 clinical trials identified, the most common injection treatment studied is platelet-rich plasma in isolation (N = 19; 16.7%). Forty-two different injection treatment types/groups are utilized. The most common PRO measure assessed was WOMAC (N = 77 trials; 67.5%). Overall there were 34 different patient-reported outcome measures used. Conclusions: Research efforts to find the most effective injection therapy for knee OA continue with a tremendous number of injection therapies still being evaluated. Substantial heterogeneity exists in these completed and ongoing trials in terms of patient demographics, OA grades, outcome scores and relatively short-term timing of assessments, with no clear standardization of testing protocol despite proposing to answer the same clinical question. We recommend that studies of this genre going forward be standardized in terms of outcome measures and longer-term follow-up time points, and should incorporate functional assessment evaluations and imaging studies.

The efficiency of platelet-rich plasma treatment in patients with knee osteoarthritis

OBJECTIVE

The aim of this study was to determine the effects of platelet-rich plasma (PRP) treatment on pain, functionality, quality of life, and cartilage thickness in patients with knee osteoarthritis (OA).

METHODS

Sixty patients with chronic knee pain were randomly separated into two groups. The first group was administered 4-ml PRP intra-articularly (IA) in three doses at one-week intervals, and the second group had only one dose of a 4-ml saline solution IA. The patients' pain was measured using the Visual Analogue Scale (VAS); functionality was measured using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC). The distal femur cartilage thickness was assessed using ultrasonography (USG).

RESULTS

All baseline parameters were similar (p> 0.05). In the first and sixth months after the treatment, the VAS scores of the PRP group were significantly low (p< 0.001). In the same group, only the pain sub-score was low in the WOMAC assessment in the first month after treatment. However, in the sixth month, all parameters of the WOMAC score were lower than those of the placebo group (p< 0.05). Cartilage thickness measurements were similar in the two groups (p< 0.05).

CONCLUSION

PRP treatment had positive effects on the pain, physical function, and quality of life of patients with knee OA, but it did not increase cartilage thickness.

Comparison Matrix-Associated Stem Cell Transplantation (MAST) with Autologous Matrix Induced Chondrogenesis plus Peripheral Blood Concentrate (AMIC+PBC) in chondral lesions at the ankle-A clinical matched-patient analysis

BACKGROUND

The aim of the study was to compare Matrix-Associated Stem Cell Transplantation (MAST) with Autologous Matrix Induced Chondrogenesis plus Peripheral Blood Concentrate (AMIC+PBC) in chondral lesions at the ankle.

METHODS

In a matched-patient clinical follow-up study, patients with chondral lesion at the ankle that were treated with MAST from April 1, 2009 to July 15, 2016, and patients that were treated with AMIC+PBC from July 17, 2016 to May 31, 2017 were included and compared. Size and location of the chondral lesions and the Visual-Analogue-Scale Foot and Ankle (VAS FA) before treatment and at follow-up were analysed. Bone Marrow Aspirate Concentrate (BMAC) was used for MAST and Peripheral Blood Concentrate (PBC) for AMIC+PBC to impregnate a collagen I/III matrix (Chondro-Gide, Wollhusen, Switzerland) that was fixed into the chondral lesion with fibrin glue.

RESULTS

One hundred and twenty-nine patients with 136 chondral lesions were included in both groups. The chondral lesions were located as follows (MAST/AMIC+PBC, n (%)), medial talar shoulder only, 59 (43)/62 (46); lateral talar shoulder only, 44 (32)/42 (31); medial and lateral talar shoulder, 7 (10)/7 (10); tibia, 19 (14)/18 (13). The lesion size was 1.6/1.8cm² on average and VAS FA was 46.9/45.7 (MAST/AMIC+PBC). For MAST/AMIC+PBC groups, 107 (83%)/105 (81%) with 112/110 previous chondral lesions completed the defined 2-year-follow-up after 24.4/23.8 months on average. VAS FA improved to 82.3/79.8 (MAST/AMIC+PBC). No parameter significantly differed between MAST and AMIC+PBC groups.

CONCLUSIONS

MAST and AMIC+PBC as part of a complex surgical approach led to improved and high validated outcome scores in 2-year-follow-up. MAST and AMIC+PBC showed similar results.

Autologous Mesenchymal Stem Cell Treatment is Consistently Effective for the Treatment of Knee Osteoarthritis: The Results of a Systematic Review of Treatment and Comparison to a Placebo Group

Background: Numerous studies have used autologous mesenchymal stem cell injections (AMSCI) to treat osteoarthritis. We hypothesized that AMSCI is an effective osteoarthritis treatment with increasing efficacy at higher doses. Methods: We conducted a PubMed search for human clinical studies using AMSCI for the treatment of osteoarthritis (OA) and a second search for placebo arms of injectate OA treatment. Inclusion criteria included treatment outcomes ratings both pre-treatment and at least 6 months post-treatment. Results: 45 AMSCI cohorts from 34 studies met criteria. All AMSCI cohorts showed improvement at mean 15.3 months post-treatment. Mean WOMAC and VAS scores improved at 6-months and at final follow-up (p < 0.0001 for all). Scores > 2 years were also significant (WOMAC p = 0.001/VAS p = 0.004). Results greatly exceeded the minimal clinically important difference (MCID) at each time point. AMSCI improvement also substantially exceeded previously published 6-month placebo-treatment improvement. No dose-response relationship was seen. AMSCI cohorts showed continuing improvement ≥ 6 months, and continued upward at one year. Placebo scores were already trending downward by 6 months. Conclusions: AMSCI is a consistently significantly effective treatment for osteoarthritis. It should no longer be stated that data is insufficient to establish AMSCI efficacy for OA. Given its excellent safety profile, AMSCI should be widely used for the treatment of osteoarthritis.

Intra-articular platelet-rich plasma vs corticosteroids in the treatment of moderate knee osteoarthritis: a single-center prospective randomized controlled study with a 1-year follow up

BACKGROUND

Osteoarthritis is the most prevalent type of arthritis, which significantly impacts the patient's mobility and quality of life. Pharmacological treatments for osteoarthritis, such as corticosteroids, produce an immediate reduction of the patient's pain as well as an improvement in the patient's mobility and quality of life, but with a limited long-term efficacy. In this context, platelet-rich plasma (PRP) infiltrations represent a therapeutic tool due to its trophic properties and its ability to control inflammatory processes, especially in musculoskeletal applications. The aim of this study is to evaluate and compare the clinical benefits of PRP when injected intra-articularly vs a commonly used corticosteroid (CS, triamcinolone acetonide, Kenalog®) in patients affected by mild to moderate symptomatic knee osteoarthritis.

METHODS

Forty patients affected by symptomatic radiologically confirmed knee osteoarthritis (Kellgren-Lawrence grades II-III) were enrolled in this randomized study. Patients randomized in the PRP group (n = 20) received an intra-articular injection of PRP (8 mL) while patients randomized in the CS group (n = 20) received an intra-articular injection of triamcinolone acetonide (1 mL of 40 mg/mL) plus lidocaine (5 mL of 2%). The pain and function of the target knee were evaluated by the VAS, IKDC, and KSS scales at the baseline (V1), 1 week (V2), 5 weeks (V3), 15 weeks (V4), 30 weeks (V5), and 1 year (V6) after treatment.

RESULTS

No serious adverse effects were observed during the follow-up period. A mild synovitis was registered in 15 patients (75%) in the PRP group within the first week after treatment which resolved spontaneously. Both treatments were effective in relieving pain and improving the knee function in the very short-term follow-up visit (1 week). A high improvement of the subjective scores was observed for both groups up to 5 weeks, with no significative differences between the groups for the VAS, IKDC, or KSS. After 15 weeks of follow-up, the PRP group showed significative improvements in all scores when compared to the CS group. Overall, the patients who received PRP treatment had better outcomes in a longer follow-up visit (up to 1 year) than those who received CS.

CONCLUSIONS

A single PRP or CS intra-articular injection is safe and improves the short-term scores of pain and the knee function in patients affected by mild to moderate symptomatic knee OA (with no significant differences between the groups). PRP demonstrated a statistically significant improvement over CS in a 1-year follow-up. This study was registered at ISRCTN with the ID ISRCTN46024618.

Importance of Timing of Platelet Lysate-Supplementation in Expanding or Redifferentiating Human Chondrocytes for Chondrogenesis

Osteoarthritis (OA) in articular joints is a prevalent disease. With increasing life expectancy, the need for therapies other than knee replacement arises. The intrinsic repair capacity of cartilage is limited, therefore alternative strategies for cartilage regeneration are being explored. The purpose of this study is first to investigate the potential of platelet lysate (PL) as a xeno-free alternative in expansion of human OA chondrocytes for cell therapy, and second to assess the effects of PL on redifferentiation of expanded chondrocytes in 3D pellet cultures. Chondrocytes were isolated from human OA cartilage and subjected to PL in monolayer culture. Cell proliferation, morphology, and expression of chondrogenic genes were assessed. Next, PL-expanded chondrocytes were cultured in 3D cell pellets and cartilage matrix production was assessed after 28 days. In addition, the supplementation of PL to redifferentiation medium for the culture of expanded chondrocytes in 3D pellets was evaluated. Glycosaminoglycan (GAG) and collagen production were evaluated by quantitative biochemical analyses, as well as by (immuno)histochemistry. A dose-dependent effect of PL on chondrocyte proliferation was found, but expression of chondrogenic markers was decreased when compared to FBS-expanded cells. After 28 days of subsequent 3D pellet culture, GAG production was significantly higher in pellets consisting of chondrocytes expanded with PL compared to controls. However, when used to supplement redifferentiation medium for chondrocyte pellets, PL significantly decreased the production of GAGs and collagen. In conclusion, chondrocyte proliferation is stimulated by PL and cartilage production in subsequent 3D culture is maintained. Furthermore, the presences of PL during redifferentiation of 3D chondrocyte strongly inhibits GAG and collagen content. The data presented in the current study indicate that while the use of PL for expansion in cartilage cell therapies is possibly beneficial, intra-articular injection of the product in the treatment of OA might be questioned.

What Is the Appropriate Price for Platelet-Rich Plasma Injections for Knee Osteoarthritis? A Cost-Effectiveness Analysis Based on Evidence From Level I Randomized Controlled Trials

PURPOSE

To identify the price of treatment at which platelet-rich plasma (PRP) is cost-effective relative to hyaluronic acid (HA) and saline solution intra-articular injections.

METHODS

A systemized review process of the PubMed, Embase, and MEDLINE databases was undertaken to identify randomized controlled trials comparing PRP with HA and saline solution with up to 1 year of follow-up. Level I trials that reported Western Ontario and McMaster Universities Arthritis Index Likert scores were included. These scores were converted into utility scores. Cost data were obtained from Centers for Medicare & Medicaid Services fee schedules. Total costs included the costs of the injectable, clinic appointments, and procedures. The change in utility scores from baseline to 6 months and 1 year for the PRP, HA, and saline solution groups was divided by total cost to determine utility gained per dollar and to identify the price needed for PRP to be cost-effective relative to these other injection options.

RESULTS

Nine randomized controlled trials met the inclusion criteria. A total of 882 patients were included: 483 in the PRP group, 338 in the HA group, and 61 in the saline solution group. Baseline mean utility scores ranged from 0.55 to 0.57 for the PRP, HA, and saline solution groups. The 6-month gains in utility were 0.12, 0.02, and -0.06, respectively. The 12-month gains in utility from before injection were 0.14, 0.03, and 0.06, respectively. The lowest total costs for HA and saline solution were $681.93 and $516.29, respectively. For PRP to be cost-effective, the total treatment cost would have to be less than $3,703.03 and $1,192.08 for 6- and 12-month outcomes, respectively.

CONCLUSIONS

For patients with symptomatic knee osteoarthritis, PRP is cost-effective, from the payer perspective, at a total price (inclusive of clinic visits, the procedure, and the injectable) of less than $1,192.08 over a 12-month period, relative to HA and saline solution.

LEVEL OF EVIDENCE

Level I, systematic review.

The Clinical Use of Platelet-Rich Plasma in Knee Disorders and Surgery-A Systematic Review and Meta-Analysis

In recent years, the interest in biological treatment of knee lesions has increased, especially the application of platelet-rich plasma is of particular note. The number of articles evaluating platelet-rich plasma (PRP) efficacy in the recovery of knee disorders and during knee surgery has exponentially increased over the last decade. A systematic review with meta-analyses was performed by assessing selected studies of local PRP injections to the knee joint. The study was completed in accordance with 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A multistep search of PubMed, Embase, Cochrane Database of Systematic Reviews, and Clinicaltrials.gov was performed to identify studies on knee surgery and knee lesion treatment with PRP. Of the 4004 articles initially identified, 357 articles focusing on knee lesions were selected and, consequently, only 83 clinical trials were analyzed using the revised Cochrane risk-of-bias tool to evaluate risk. In total, seven areas of meta-analysis reported a positive effect of PRP. Among them, 10 sub-analyses demonstrated significant differences in favor of PRP when compared to the control groups (p < 0.05). This study showed the positive effects of PRP, both on the recovery of knee disorders and during knee surgery; however further prospective and randomized studies with a higher number of subjects and with lower biases are needed.

The effects of platelet-rich plasma injection in knee and hip osteoarthritis: a meta-analysis of randomized controlled trials

OBJECTIVE

We conducted this updated meta-analysis to evaluate the effects of PRP in patients with knee or hip OA.

METHOD

PubMed, Embase, and Web of Science were searched to identify randomized controlled trials (RCTs) that compared the efficacy of PRP with other intra-articular injections. The outcomes of interest included Western Ontario and McMaster (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), Visual Analog Scale (VAS), Harris Hip Score (HHS), and International Knee Documentation Committee (IKDC).

RESULTS

Twenty-four RCTs with 21 at knee OA and three at hip OA were included in this meta-analysis. The PRP injections significantly improved the WOMAC score, VAS score, IKDC score, and HHS score as compared with comparators. The WOMAC pain, stiffness, and physical function scores were also significantly better in the PRP group than in the control group. Most of the evaluated parameters that favored PRP were observed in knee OA but not in hip OA, at short-term (at 1, 2, 3, 6, 12 months) but not long-term follow-up (at 18 months), in RCTs with low risk of bias.

CONCLUSIONS

Intra-articular PRP injection provided better effects than other injections for OA patients, especially in knee OA patients, in terms of pain reduction and function improvement at short-term follow-up. Key Points • This updated meta-analysis, based on great sample size and high-quality studies, evaluates the effects of PRP in patients with knee or hip OA. • Intra-articular PRP injection provided better effects than other injections for OA patients. • Most of the evaluated parameters that favored PRP were observed in knee OA at short term (at 1, 2, 3, 6, 12 months).

Orthobiologics in Elbow Injuries

Orthobiologics are exciting tools providing promising results for difficult orthopedic conditions. In the elbow there is high-level evidence for their use in lateral epicondylopathy and encouraging evidence for other elbow pathologies. This article provides an in-depth review of the current literature for the use of orthobiologics in elbow injuries.

High Intensity Interval Exercise Increases Platelet and Transforming Growth Factor-β Yield in Platelet-Rich Plasma

BACKGROUND

Platelet-rich plasma (PRP) is an emerging orthobiologic treatment for musculoskeletal conditions like osteoarthritis. Two studies have demonstrated the influence of longer duration exercise on PRP composition, but no study has ever explored the impact of high intensity interval exercise (HIIE) on PRP content.

OBJECTIVE

To quantify cellular and growth factor content changes in PRP after 4 minutes of HIIE.

DESIGN

Controlled laboratory pilot study.

SETTING

Academic sports medicine center.

PARTICIPANTS

Ten healthy volunteers (5 male, 5 female).

INTERVENTION

Volunteers had PRP prepared from 15 mL of whole blood using a single spin, plasma-based system (autologous conditioned plasma [ACP]) immediately before and after 4 minutes of HIIE on a stationary exercise bike (Tabata protocol).

MAIN OUTCOME MEASURE

The PRP was sent for complete blood counts and enzyme-linked immunosorbent assay (ELISA) to quantify transforming growth factor (TGF)-β, platelet-derived growth factor (PDGF), insulin-like growth factor (IGF)-1, and vascular endothelial growth factor (VEGF).

RESULTS

Mean platelet count in PRP increased from 367.4 ± 57.5 k/μL to 497.7 ± 93.3 k/μL after 4 minutes of HIIE (P < .001). TGF-β also increased from 8237.2 ± 7676.5 pg/mL to 21 535.7 ± 4062.6 pg/mL postexercise (P = .004). The other cellular components (leukocytes, red blood cells, and mean platelet volume) and growth factors (PDGF, IGF-1, and VEGF) were not significantly changed.

CONCLUSIONS

A short 4-minute bout of HIIE significantly increased the total platelet count and TGF-β concentration in PRP.

Bone Marrow Aspirate Concentrate Is Equivalent to Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis at 1 Year: A Prospective, Randomized Trial

Background:

Approximately 47 million people in the United States have been diagnosed with arthritis. Autologous platelet-rich plasma (PRP) injections have been documented to alleviate symptoms related to knee osteoarthritis (OA) in randomized controlled trials, systematic reviews, and meta-analyses. Autologous bone marrow aspirate concentrate (BMC) injections have also emerged as a treatment option for knee OA, with a limited clinical evidence base.

Purpose:

To compare the efficacy of BMC to PRP for the treatment of knee OA regarding pain and function at multiple time points up to 12 months after an injection. We hypothesized that BMC will be more effective in improving outcomes in patients with knee OA.

Study Design:

Randomized controlled trial; Level of evidence, 2

Methods:

A total of 90 participants aged between 18 and 80 years with symptomatic knee OA (Kellgren-Lawrence grades 1-3) were randomized into 2 study groups: PRP and BMC. Both groups completed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and subjective International Knee Documentation Committee (IKDC) questionnaires before and 1, 3, 6, 9, and 12 months after a single intra-articular injection of leukocyte-rich PRP or BMC.

Results:

There were no statistically significant differences in baseline IKDC or WOMAC scores between the 2 groups. All IKDC and WOMAC scores for both the PRP and BMC groups significantly improved from baseline to 1 month after the injection (P < .001). These improvements were sustained for 12 months after the injection, with no difference between PRP and BMC at any time point.

Conclusion:

Both PRP and BMC were effective in improving patient-reported outcomes in patients with mild to moderate knee OA for at least 12 months; neither treatment provided a superior clinical benefit. Autologous PRP and BMC showed promising clinical potential as therapeutic agents for the treatment of OA, and while PRP has strong clinical evidence to support its efficacy, BMC has limited support. This study did not prove BMC to be superior to PRP, providing guidance to clinicians treating OA. It is possible that the results were affected by patients knowing that there was no control group.

Registration:

NCT03289416 (ClinicalTrials.gov identifier).

Platelet Concentrates in Musculoskeletal Medicine

Platelet concentrates (PCs), mostly represented by platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) are autologous biological blood-derived products that may combine plasma/platelet-derived bioactive components, together with fibrin-forming protein able to create a natural three-dimensional scaffold. These types of products are safely used in clinical applications due to the autologous-derived source and the minimally invasive application procedure. In this narrative review, we focus on three main topics concerning the use of platelet concentrate for treating musculoskeletal conditions: (a) the different procedures to prepare PCs, (b) the composition of PCs that is related to the type of methodological procedure adopted and (c) the clinical application in musculoskeletal medicine, efficacy and main limits of the different studies.

Orthobiologics for the Hip Region: A Narrative Review

Management of hip region disorders is challenging. Orthobiologic treatments including platelet rich plasma (PRP), mesenchymal stem cells, and amniotic injectables have gained popularity as promising treatments despite a lack of robust evidence for their effectiveness. We review rationale and current evidence for orthobiologics for three common hip region conditions: hip osteoarthritis, gluteal tendinopathy, and proximal hamstring tendinopathy. Overall, the current state of evidence is extremely limited for orthobiologic treatments and is predominantly relevant to PRP injections. There is currently a lack of data to support the use of mesenchymal stem cells or amniotic injectables in these conditions of the hip.

A Practical Guide for the Current Use of Biologic Therapies in Sports Medicine

Over the past decade, there has been an increased interest in the use of biologic therapies in sports medicine. Although these technologies are in relatively early stages of development, there have been substantial increases in marketing, patient demand, and clinical utilization of biologics, including platelet-rich plasma, bone marrow aspirate concentrate, and other cell-derived therapies. Direct-to-consumer marketing of biologics has also proliferated but is largely unregulated, and clinicians must accurately convey the safety and efficacy profiles of these therapies to patients. Because most insurance companies consider biologic treatments to be experimental or investigational for orthopaedic applications given the lack of high-quality evidence to support their efficacy, patients receiving these treatments often make substantial out-of-pocket payments. With a range of treatment costs among centers offering biologics, there is a need for appropriate and sustainable pricing and reimbursement models. Clinicians utilizing biologics must also have a thorough understanding of the recently clarified Food and Drug Administration guidelines that regulate the clinical use of cell and tissue products. There is a lack of consensus on the optimal preparation, source, delivery method, and dosing of biologic therapies, which has been exacerbated by a lack of sufficient experimental detail in most published studies. Future research must better identify the biologic target of treatment, adhere to better standards of reporting, and better integrate researchers, industry, and regulatory bodies to optimize applications.

Platelet-Rich Plasma for Sport-Active Patients with Knee Osteoarthritis: Limited Return to Sport

Objective

To evaluate a cohort of sport-active patients suffering from cartilage degeneration and OA, in terms of clinical outcome and return to sport (RTS) after platelet-rich plasma (PRP) injective treatment.

Design

This study included forty-seven sport-active patients ≤50 years old with unilateral symptomatic knee cartilage degeneration or OA. Patients received 3 PRP injections and were prospectively evaluated at baseline and then at 2, 6, 12, and 24 months follow-up by IKDC subjective EQ-VAS, and Tegner scores. Furthermore, patients were asked about their RTS, in terms of return to any sport level or to their activity level before symptoms onset.

Results

IKDC subjective score improved significantly at all follow-ups, changing from 59.2 ± 13.6 to 70.6 ± 13 at 12 months and to 76.7 ± 12.5 at 24 months (p < 0.0005). A similar outcome was observed with the EQ-VAS score. Tegner score improved from 3.6 ± 1.4 to 4.8 ± 0.9 at 24 months (p < 0.0005). A similar outcome was observed with the EQ-VAS score. Tegner score improved from 3.6 ± 1.4 to 4.8 ± 0.9 at 24 months (p < 0.0005). A similar outcome was observed with the EQ-VAS score. Tegner score improved from 3.6 ± 1.4 to 4.8 ± 0.9 at 24 months (p < 0.0005). A similar outcome was observed with the EQ-VAS score. Tegner score improved from 3.6 ± 1.4 to 4.8 ± 0.9 at 24 months (

Conclusions

Sport-active patients affected by knee OA can benefit from PRP injections, with pain and function improvement over time. However, results are less satisfactory in terms of RTS since only half can achieve the same sport level as before the onset of symptoms. Patients undergoing PRP treatment should be made aware of their low chances to go back to high-impact sport activities.

Plasma miR-200c-3p, miR-100-5p, and miR-1826 serve as potential diagnostic biomarkers for knee osteoarthritis: Randomized controlled trials

OBJECTIVE

To study the potential diagnostic value of plasma miR-200c-3p, miR-100-5p, and miR-1826 levels in knee osteoarthritis (KOA).

METHODS

Real-time quantitative PCR (RT-PCR) was used to measure the expression levels of serum miR-200c-3p, miR-100-5p, and miR-1826 in 150 KOA patients and 150 control controls. In addition, the levels of DNMT3A, ZEB1, MMP13, and CTNNB1 mRNAs in the synovial fluid were also measured by RT-PCR.

RESULTS

The expression levels of miR-100-5p, miR-200c-3p, and miR-1826 in the synovial fluid of 150 KOA patients were significantly lower than those in 54 controls (P < .001). In the synovial fluid, the miR-100-5p and DNMT3A mRNA levels, miR-100-5p and ZEB1 mRNA levels, miR-200c-3p and MMP13 mRNA levels, and miR-1826 and CTNNB1 mRNA levels were all negatively correlated (r = -0.83, -0.81, -0.83, -0.58, respectively). The AUCs of the diagnosis for KOA using the plasma levels of miR-200c-3p, miR-100-5p, and miR-1826 were 0.755, 0.845, and 0.749, respectively.

CONCLUSION

The plasma levels of miR-200c-3p, miR-100-5p, and miR-1826 are of potentially high value in the diagnosis of KOA.

Intra-articular platelet-rich plasma injection for knee osteoarthritis: a summary of meta-analyses

OBJECTIVE

The purpose of this study was (1) to perform a summary of meta-analyses comparing platelet-rich plasma (PRP) injection with hyaluronic acid (HA) and placebo injection for KOA patients, (2) to determine which meta-analysis provides the best available evidence to making proposals for the use of PRP in the treatment of KOA patients, and (3) to highlight gaps in the literature that require future investigation.

MATERIAL AND METHODS

PubMed, EMBASE, and Cochrane databases search were performed for meta-analyses which compared PRP injection with HA or placebo. Clinical outcomes and adverse events were extracted from these meta-analyses. Meta-analysis quality was assessed using the Quality of Reporting of Meta-analyses (QUOROM) systems and the Oxman-Guyatt quality appraisal tool. The Jadad decision algorithm was also used to determine which meta-analysis provided the best available evidence.

RESULTS

Four meta-analyses were included in our study, and all of these articles were Level I evidence. The QUOROM score of each included meta-analysis range from 14 to 17 points (mean score 15, maximum score 18), and the Oxman-Guyatt score range from 4 to 6 points (mean score 5, maximum score 7). Three meta-analyses indicated PRP showed more benefit in pain relief and functional improvement than the control group, and the other one suggested no difference between these groups. All included meta-analyses found no statistical difference in adverse events between these groups. In addition, a meta-analysis conducted by Shen et al. got the highest methodological quality score and suggested that PRP provided better pain relief and function improvement in the treatment of KOA.

CONCLUSIONS

For short-term follow-up (≤1 year), intra-articular PRP injection is more effective in terms of pain relief and function improvement in the treatment of KOA patients than HA and placebo, and there is no difference in the risk of an adverse event between PRP and HA or placebo.

LEVEL OF EVIDENCE

Level I evidence, a summary of meta-analyses TRIAL REGISTRATION: PROSPERO ID CRD42018116168.

Platelet-rich plasma combined with injectable hyaluronic acid hydrogel for porcine cartilage regeneration: a 6-month follow-up

Based on our previous study, the utilization of an ultraviolet light photo-cross-linkable hyaluronic acid (HA) hydrogel integrated with a small molecule kartogenin-encapsulated nanoparticles obtained good reconstruction of osteochondral defects in a rabbit model, indicating the superiority of injectable hydrogel-based scaffolds in cartilage tissue engineering. Platelet-rich plasma (PRP), rich in various growth factors, proteins and cytokines, is considered to facilitate cartilage healing by stimulating cell proliferation and inducing chondrogenesis in cartilage defect site. The aim of this study was to test the therapeutic feasibility of autologous PRP combined with injectable HA hydrogel on cartilage repair. The focal cartilage defects with different critical sizes in the medial femoral condyle of a porcine model were used. At 6 months, the minipigs were sacrificed for assessment of macroscopic appearance, magnetic resonance imaging, micro-computed tomography, histology staining and biomechanics. The HA hydrogel combined with PRP-treated group showed more hyaline-like cartilage exhibited by macroscopic appearance and histological staining in terms of extracellular matrix and type II collagen without formation of hypertrophic cartilage, indicating its capacity to improve cartilage healing in the minipig model evaluated at 6 months, with full-thickness cartilage defect of 8.5 mm diameter and osteochondral defect of 6.5 mm diameter, 5 mm depth exhibiting apparent regeneration.

The influence of sample size and gender composition on the meta-analysis conclusion of platelet-rich plasma treatment for osteoarthritis

Objective

The magnitude of the therapeutic effects of intra-articular injection of platelet-rich plasma (PRP) on osteoarthritis (OA) is still under debate. The goal of this study that was a systematic review of randomised controlled trials ​of PRP injections for the treatment of OA was to elucidate the therapeutic efficacy of PRP.

Methods

Electronic databases of PubMed, CENTRAL, EMBASE, EBSCO, ClinicalTrials.gov, and International Clinical Trials Registry Platform ​were searched from inception to June 2018 for RCTs that compared PRP injections to controls in patients with OA. A random-effects approach was used to compile data and subgroups according to trial size (large trials versus small trials), patient profile (age and gender), and PRP preparation method was performed.

Results

Thirty trials met the inclusion criteria and were analysed. All results had unexplained statistical heterogeneity. Patients treated with PRP compared with control showed statistically relevant pain relief and function improvement at short term (standardised mean difference [SMD] ​= ​−0.62, 95% confidence interval [CI]: −0.98 to −0.27, P ​= ​0.0006, SMD ​= ​−0.74, 95% CI: −1.11 to 0.36, P ​= ​0.0001, respectively), medium term (SMD ​= ​−0.53, 95% CI: −0.83 to −0.23, P ​= ​0.0006, SMD ​= ​−0.50, 95% CI: −0.75 to −0.25, P ​= ​0.0006), and long term (SMD ​= ​−0.69, 95% CI: −1.08 to −0.30, P ​= ​0.0006, SMD ​= ​−0.68, 95% CI: −0.1.09 to −0.27, P ​= ​0.001, respectively). A subgroup analysis of the data from large trials and from trials composed of less than 50% female patients revealed that therapeutic effects of the treatment are insignificant.

Conclusions

According to the currently available data, PRP injections are beneficial for pain relief and function improvement in patients with OA. This meta-analysis, however, demonstrated that the efficacy of PRP is related to sample size and gender composition. Thus, more randomised controlled trials of high quality and larger patient size, also including gender aspects, are required to understand this phenomenon.

The translational potential of this article

The translation potential of this meta-analysis is that provided another perspective to analyse the treatment effect of PRP for OA. In future research, phenotypes subpopulation and gender difference of OA patient should be considered for PRP treatment.

Variability of the Composition of Growth Factors and Cytokines in Platelet-Rich Plasma From the Knee With Osteoarthritis

PURPOSE

To investigate the composition and concentration of growth factors and cytokines in platelet-rich plasma (PRP) with knee osteoarthritis and to explore the association of the concentration of growth factors and cytokines with the platelet count of PRPs.

METHODS

Patients who visited outpatient clinic with symptomatic knee osteoarthritis (Kellgren-Lawrence grades 1 to 3) and had no blood dyscrasia were enrolled from October 2014 to March 2015. PRPs were obtained using a commercial system. Concentrations of growth factors and cytokines were measured with an enzyme-linked immunosorbent assay. Anabolic factors (platelet-derived growth factor [PDGF]-AA, -BB, and -AB, transforming growth factor-β, vascular endothelial growth factor [VEGF], epidermal growth factor [EGF], basic fibroblast growth factor [bFGF], and insulin-like growth factor 1), catabolic factors (interleukin [IL]-1β and matrix metalloproteinase 13), and catabolic blockers (IL-1 receptor antagonist) were included. The degree of variation was determined by coefficient of variation (CoV).

RESULTS

105 patients were included. Growth factors and cytokines showed wide variation. bFGF showed the highest variation (CoV 78.45), and transforming growth factor-β1 showed the lowest variation (CoV 5.30). Platelet count in PRP showed a positive correlation with PDGF-BB and -AB, and VEGF (r = 0.270, P = .005; r = 0.231, P = .018; and r = 0.200, P = .041, respectively) and was negatively correlated with IL-1β (r = -0.220, P = .025).

CONCLUSION

Growth factors and cytokines in PRPs obtained from patients with knee osteoarthritis show a wide variation; the highest variation was shown in bFGF. Platelet counts associated positively with PDGF-AB and -BB and VEGF and negatively with IL-1β.

CLINICAL RELEVANCE

This information leads to the concept that variation and association of specific factors needs to be taken into consideration for future investigations of PRPs in clinical application in patients with knee osteoarthritis.

Multiple Platelet-Rich Plasma Injections Versus Single Platelet-Rich Plasma Injection in Early Osteoarthritis of the Knee: An Experimental Study in a Guinea Pig Model of Early Knee Osteoarthritis

BACKGROUND

Platelet-rich plasma (PRP) has emerged as the forerunner among disease-modifying treatment options for early osteoarthritis (OA) of the knee. However, no consensus is available regarding optimum dosing schedules.

PURPOSE

To determine whether multiple injections of PRP (3 injections) provide better short-term and long-term results than a single injection of PRP in a guinea pig model of knee OA.

STUDY DESIGN

Controlled laboratory study.

METHODS

36 Dunkin-Hartley guinea pigs (weighing ~600-800 g) were chosen for this study. The animals were assigned to group DC (disease control group), group G1 (single-PRP group), and group G2 (multiple-PRP group) containing 10, 10, and 12 animals, respectively. Another 4 animals were used for preparation of allogenic PRP. Groups G1 and G2 received 1 and 3 injections of PRP, respectively, at weekly intervals in the intervention knee while the contralateral knee was injected with normal saline. Group DC received no intervention in either knee. Half of the animals from each group (subgroups DC.3, G1.3, and G2.3) were sacrificed at 3 months, and the remaining half (subgroups DC.6, G1.6, and G2.6) were sacrificed at 6 months after intervention. Both knee joints were harvested for histological assessment of articular cartilage and synovium.

RESULTS

The mean synovial scores for groups G1 and G2 were significantly better than those for group DC at 3 months. No difference was found between groups G1 and G2 at 3 months. At 6 months, group G2 had significantly better mean synovial scores than group G1 and group DC. The mean articular cartilage scores in group G2 were significantly better than those in group DC at 3 months. However, at 6 months, no significant difference was found among any of the groups in terms of mean articular scores.

CONCLUSION

Both single and multiple injections of PRP exert similar anti-inflammatory effects on the synovium in the short term. However, this effect is sustained in the long term only for multiple injections. Multiple injections of PRP exert a chondroprotective effect, but only in the short term. This effect is not seen with a single injection of PRP.

CLINICAL RELEVANCE

This study provides insight into the histological basis for the superiority of multiple injections of PRP.

Characterization of Growth Factors, Cytokines, and Chemokines in Bone Marrow Concentrate and Platelet-Rich Plasma: A Prospective Analysis

BACKGROUND

Platelet-rich plasma (PRP) and bone marrow concentrate (BMC) are orthobiologic therapies with numerous growth factors and other bioactive molecules. Before the clinical utility of PRP and BMC is optimized as a combined therapy or monotherapy, an improved understanding of the components and respective concentrations is necessary.

PURPOSE

To prospectively measure and compare anabolic, anti-inflammatory, and proinflammatory growth factors, cytokines, and chemokines in bone marrow aspirate (BMA), BMC, whole blood, leukocyte-poor PRP (LP-PRP), and leukocyte-rich PRP (LR-PRP) from samples collected and processed concurrently on the same day from patients presenting for elective knee surgery.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Patients presenting for elective knee surgery were prospectively enrolled over a 3-week period. Whole blood from peripheral venous draw and BMA from the posterior iliac crest were immediately processed via centrifugation and manual extraction methods to prepare LR-PRP, LP-PRP, and BMC samples, respectively. BMA, BMC, whole blood, LR-PRP, and LP-PRP samples were immediately assayed and analyzed to measure protein concentrations.

RESULTS

BMC had a significantly higher interleukin 1 receptor antagonist (IL-1Ra) concentration than all other preparations (all P < .0009). LR-PRP also had a significantly higher IL-1Ra concentration than LP-PRP (P = .0006). There were no significant differences in IL-1Ra concentration based on age, sex, body mass index, or chronicity of injury in all preparations. LR-PRP had significantly higher concentrations of platelet-derived growth factor AA (PDGF-AA) and PDGF-AB/BB than all other preparations (all P < .0006). LR-PRP also had significantly higher concentrations of matrix metalloproteinase 1 (MMP-1) and soluble CD40 ligand than all other preparations (all P < .004). LP-PRP had significantly higher concentrations of MMPs, namely MMP-2, MMP-3, and MMP-12, than all other preparations (all P < .007).

CONCLUSION

BMC is a clinically relevant source of anti-inflammatory biologic therapy that may be more effective in treating osteoarthritis and for use as an intra-articular biologic source for augmented healing in the postsurgical inflammatory and healing phases, owing to its significantly higher concentration of IL-1Ra as compared with LR-PRP and LP-PRP. Additionally, LR-PRP had a significantly higher concentration of IL-1Ra than LP-PRP. In cases where increased vascularity and healing are desired for pathological or injured tissues, including muscle and tendon, LR-PRP may be optimal given its higher overall concentrations of PDGF, TGF-β, EGF, VEGF, and soluble CD40 ligand.

Impact of Platelet-Rich Plasma Use on Pain in Orthopaedic Surgery: A Systematic Review and Meta-analysis

CONTEXT

Amid extensive debate, evidence surrounding the use of platelet-rich plasma (PRP) for musculoskeletal injuries has rapidly proliferated, and an overall assessment of efficacy of PRP across orthopaedic indications is required.

OBJECTIVES

(1) Does PRP improve patient-reported pain in musculoskeletal conditions? and (2) Do PRP characteristics influence its treatment effect?

DATA SOURCES

MEDLINE, EMBASE, Cochrane, CINAHL, SPORTDiscus, and Web of Science libraries were searched through February 8, 2017. Additional studies were identified from reviews, trial registries, and recent conferences.

STUDY SELECTION

All English-language randomized trials comparing platelet-rich therapy with a control in patients 18 years or older with musculoskeletal bone, cartilage, or soft tissue injuries treated either conservatively or surgically were included. Substudies of previously reported trials or abstracts and conference proceedings that lacked sufficient information to generate estimates of effect for the primary outcome were excluded.

STUDY DESIGN

Systematic review and meta-analysis.

LEVEL OF EVIDENCE

Level 1.

DATA EXTRACTION

All data were reviewed and extracted independently by 3 reviewers. Agreement was high between reviewers with regard to included studies.

RESULTS

A total of 78 randomized controlled trials (5308 patients) were included. A standardized mean difference (SMD) of 0.5 was established as the minimum for a clinically significant reduction in pain. A reduction in pain was associated with PRP at 3 months (SMD, -0.34; 95% CI, -0.48 to -0.20) and sustained until 1 year (SMD, -0.60; 95% CI, -0.81 to -0.39). Low- to moderate-quality evidence supports a reduction in pain for lateral epicondylitis (SMD, -0.69; 95% CI, -1.15 to -0.23) and knee osteoarthritis (SMD, -0.91; 95% CI, -1.41 to -0.41) at 1 year. PRP characteristics did not influence results.

CONCLUSION

PRP leads to a reduction in pain; however, evidence for clinically significant efficacy is limited. Available evidence supports the use of PRP in the management of lateral epicondylitis as well as knee osteoarthritis.

Osteoarthritis- a systematic review of long-term safety implications for osteoarthritis of the knee

BACKGROUND

There is no cure for knee osteoarthritis (KOA) and typically patients live approximately 30-years with the disease. Most common medical treatments result in short-term palliation of symptoms with little consideration of long-term risk. This systematic review aims to appraise the current evidence for the long-term (≥12 months) safety of common treatments for knee osteoarthritis (KOA).

METHODS

Cochrane Database of Systematic Reviews, Medline and PubMed were systematically searched from 1990 to July 2017, inclusive. Inclusion criteria were 1) peer-reviewed publications investigating treatments for KOA referred to in the Australian Clinical Care Standard and/or Therapeutic Guidelines: Rheumatology 2) specifically addressing safety of the treatments 3) with ≥12 months of follow-up and 4) Downs and Black quality score ≥ 13.

RESULTS

Thirty-four studies fulfilled the inclusion criteria. Lifestyle modifications (moderate exercise and weight loss), paracetamol, glucosamine, Intraarticular Hyaluronic Acid (IAHA) and platelet-rich-plasma (PRP) injections have a low risk of harm and beneficial ≥12 month outcomes. Although Nonsteroidal Anti-inflammatory Drugs (NSAIDs) provide pain relief, they are associated with increased risk of medical complications. Cortisone injections are associated with radiological cartilage degeneration at > 12 months. Arthroscopy for degenerative meniscal tears in KOA leads to a 3-fold increase in total knee arthroplasty (TKA). TKA improves primary outcomes of KOA but has a low rate of significant medical complications.

CONCLUSIONS

Given the safety and effectiveness of lifestyle interventions such as weight loss and exercise, these should be advocated in all patients due to the low risk of harm. The use of NSAIDs should be minimized to avoid gastrointestinal complications. Treatment with opioids has a lack of evidence for use and a high risk of long-term harm. The use of IAHA and PRP may provide additional symptomatic benefit without the risk of harm. TKA is associated with significant medical complications but is justified by the efficacy of joint replacement in late-stage disease.

TRIAL REGISTRATION

PROSPERO International prospective register for systematic reviews; registration number CRD42017072809 .

Biologic Therapies for the Treatment of Knee Osteoarthritis

BACKGROUND

The use of biologic therapies for the management of knee osteoarthritis has increased, despite insufficient evidence of efficacy. Our aim was to complete a systematic review and analysis of reports utilizing the highest level-of-evidence evaluating: (1) platelet-rich plasma injections (PRPs); (2) bone marrow-derived mesenchymal stem cells (BMSCs); (3) adipose-derived mesenchymal stem cells (ADSCs); and (4) amnion-derived mesenchymal stem cells (AMSCs).

METHODS

PubMed, Embase, and Cochrane Library databases were queried for studies evaluating PRP injections, BMSCs, ADSCs, and AMSCs in patients with knee osteoarthritis. Of 1009 studies identified within the last 5 years, 123 met inclusion criteria. A comprehensive analysis of all levels-of-evidence was performed, as well as separate analysis on level-of-evidence I studies. Level-of-evidence was determined by the American Academy of Orthopedic Surgeons classification system.

RESULTS

Although the majority of PRP reports demonstrated improvements in pain and/or function, others revealed no substantial improvements. Similar findings were noted for BMSCs, ADSCs, and AMSCs. Assessments of BMSC studies yielded majority with positive clinical results, although short-lived. Studies on ADSCs revealed improved clinical outcomes, but equivocal radiographic outcomes. Studies evaluating AMSCs demonstrated improvements in pain and function, and decreased radiographic evidence of osteoarthritis.

CONCLUSION

Despite some promising early results for PRP, BMSC, ADSC, and AMSC therapies, the majority of level-of-evidence I studies have multiple problems: small sample sizes, potentially inappropriate control cohorts, short-term follow-up, and so on. Despite the limitations, there still appears to be evidence justifying their use for knee osteoarthritis management. More high-level, larger human studies utilizing standardized protocols are needed.

Interventional radiology techniques for pain reduction and mobility improvement in patients with knee osteoarthritis

Osteoarthritis of the knee is the most common cause of chronic knee pain being more prevalent in middle-aged and elderly patients. Symptomatic patients complain of pain and mobility impairment. Therapeutic armamentarium includes physical therapy, oral pharmacologic therapy, intra-articular injections, nerve ablation or modulation, trans-catheter arterial embolization, minimally invasive arthroscopic treatment and partial or total knee arthroplasty. Interventional radiology therapies for knee osteoarthritis include intra-articular injections, neurotomy and neuromodulation techniques as well as transcatheter intra-arterial therapies. These therapies aim to control pain and inflammation, improve mobility and function whilst the novel cell-based therapies have the potential for bone and cartilage regenerative repair facilitating the delay to surgery. The purpose of this review is to illustrate the technical aspects, the indications and the methodology of local therapies for knee osteoarthritis performed by interventional radiologists and provide current evidence.

The Role of Orthobiologics in the Management of Osteoarthritis and Focal Cartilage Defects

Individuals with osteoarthritis have a diminished quality of life, and the condition is a major cause of disability. Newer biologic treatments have been developed that are believed to modify disease progression. These predominantly include hyaluronic acid, platelet-rich plasma, bone marrow aspirate concentrate, and adipose-derived mesenchymal stem cells. There is conflicting evidence regarding the use of orthobiologics for osteoarthritis and for focal chondral defects, although most studies indicate that injections of biologics are safe and without significant adverse effects. [Orthopedics. 2019; 42(2):66-73.].

Platelet-rich plasma in osteoarthritis treatment: review of current evidence

Platelet-rich plasma (PRP) is defined as a volume of plasma with a platelet concentration higher than the average in peripheral blood. Many basic, preclinical and even clinical case studies and trials report PRP’s ability to improve musculoskeletal conditions including osteoarthritis, but paradoxically, just as many conclude it has no effect. The purpose of this narrative review is to discuss the available relevant evidence that supports the clinical use of PRP in osteoarthritis, highlighting those variables we perceive as critical. Here, recent systematic reviews and meta-analyses were used to identify the latest randomized controlled trials (RCTs) testing a PRP product as an intra-articular treatment for knee osteoarthritis, compared with an intra-articular control (mostly hyaluronic acid). Conclusions in the identified RCTs are examined and compared. In total, five recent meta-analyses and systematic reviews were found meeting the above criteria. A total of 19 individual trials were identified in the five reviews but only 9 were level of evidence I RCTs, and many had moderate or high risks of bias. At present, results from these RCTs seem to favor PRP use over other intra-articular treatments to improve pain scales in the short and medium term (6–12 months), but the overall level of evidence is low. As a result, clinical effectiveness of PRP for knee osteoarthritis treatment is still under debate. This is, prominently, the result of a lack of standardization of PRP products, scarceness of high quality RCTs not showing high risks of bias, and poor patient stratification for inclusion in the RCTs.

Effects of Platelet-Rich Plasma on Pain and Muscle Strength in Patients With Knee Osteoarthritis

OBJECTIVE

No studies comparing the effects of platelet-rich plasma (PRP) injection and placebo injection in bilateral knee osteoarthritis in the same patient, or discussing muscle strength after PRP injection, have been published.

DESIGN

Twenty patients with bilateral knee osteoarthritis were eligible, and 40 knees were randomized into two groups: PRP (knees [right or left by a coin toss] receiving a single intra-articular PRP injection) and saline group (the contralateral knee of the same patient, into which single 4-mL intra-articular injection of normal saline was administered). The primary outcome measure was Western Ontario and McMaster's Universities Osteoarthritis Index and the secondary included isokinetic test results. The evaluation was at baseline and at 2 wks, 1, 3, and 6 mos after injection.

RESULTS

The PRP group showed a significant reduction in the Western Ontario and McMaster's Universities Osteoarthritis Index pain and total scores compared with normal saline group (P < 0.05). Although a significantly greater percentage of knee strength (extensor > flexor) was found in the PRP group during a longer follow-up period, PRP treatment resulted in insignificant differences in muscle strength compared with normal saline.

CONCLUSIONS

Platelet-rich plasma treatment significantly improves pain, stiffness, and disability in patients with knee osteoarthritis compared with normal saline treatment. Additional strength training is recommended to enhance muscle strength recovery.

The use of PRP injections in the management of knee osteoarthritis

Osteoarthritis (OA) is a degenerative disease involving joint damage, an inadequate healing response and progressive deterioration of the joint architecture that commonly affects the knee and/or hip joints. It is a major world public health problem and is predicted to increase rapidly with an ageing population and escalating rate of obesity. Autologous blood-derived products possess much promise in the repair and regeneration of tissue and have important roles in inflammation, angiogenesis, cell migration and metabolism in pathological conditions, including OA. Utilising platelet-rich plasma (PRP) to treat tendon, ligament and skeletal muscle has shown variable results across many studies with the current evidence base for the efficacy of PRP in treating sports injuries remaining inconclusive. More uniformly positive results have been observed by various studies for PRP in OA knee in comparison to hyaluronic acid, other intra-articular injections and placebo than in other musculoskeletal tissue. However, methodological concerns as well as satisfactory PRP product classification prevent the true characterisation of this treatment. Thus, further research is required to investigate how leukocyte inclusion, activation and platelet concentration affect therapeutic efficacy. Furthermore, the optimisation of timing, dosage, volume, frequency and rehabilitation strategies need to be ascertained. For knee OA management, these concerns must be addressed before this promising treatment can be widely implemented.

Platelet-Rich Plasma Versus Hyaluronic Acid Injections for the Treatment of Knee Osteoarthritis: Results at 5 Years of a Double-Blind, Randomized Controlled Trial

BACKGROUND

Platelet-rich plasma (PRP) injections have been proposed as a new conservative option for knee degeneration to provide symptomatic relief and delay surgical intervention. Although the current literature provides some evidence on the benefits of this technique compared with viscosupplementation, no studies have been performed to compare their long-term effects.

PURPOSE

To compare the long-term clinical outcomes provided by intra-articular injections of either PRP or hyaluronic acid (HA) to treat knee degenerative disease.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients with a history of chronic symptomatic knee degenerative changes and osteoarthritis (Kellgren-Lawrence grade 0-3) were enrolled: 192 patients were randomized to undergo 3 blinded weekly intra-articular injections of either PRP or HA. Patients were prospectively evaluated before the injection and then at 2, 6, 12, and 24 months and a mean of 64.3 months (SD, 7.8 months) of follow-up. Evaluation was based on International Knee Documentation Committee (IKDC) subjective (main outcome), EuroQol visual analog scale, and Tegner scores; 167 patients reached the final evaluation.

RESULTS

Both treatments were effective in improving knee functional status and symptoms over time: Mean ± SD IKDC subjective score improved significantly for both PRP and HA groups ( P < .0005) and remained stable over time up to 24 months (from 53.3 ± 14.3 to 67.3 ± 18.1 and from 50.3 ± 13.2 to 62.1 ± 20.8 for PRP and HA groups, respectively). At final evaluation, a significant IKDC reduction was observed in both treatment groups, with the PRP group still presenting significantly higher values compared with baseline: PRP 60.5 ± 19.0 ( P < .001 vs baseline), HA 55.7 ± 18.8 (not significant vs baseline). A comparative analysis showed no significant intergroup difference in any of the clinical scores at any follow-up point. The median duration of patient subjective perception of symptomatic relief was 9 months for HA and 12 months for PRP (not significant). The only significant difference was observed in the rate of reintervention at 24 months, which was significantly lower in the PRP group (22.6% vs 37.1%, P = .036).

CONCLUSION

Both treatments were effective in improving knee functional status and symptoms over time. PRP did not provide an overall superior clinical improvement compared with HA in terms of either symptomatic-functional improvement at different follow-up points or effect duration.

REGISTRATION

NCT01670578 (ClinicalTrials.gov identifier).

Lower range of molecular weight of xanthan gum inhibits apoptosis of chondrocytes through MAPK signaling pathways

LRWXG has previously been reported to have a protective effect on chondrocytes, preventing apoptosis induced by oxidative stress. In this study, we were aimed at determining whether LRWXG exerts its anti-apoptotic activity through the MAPK signaling pathways in chondrocytes. Our results show that, at the cellular level, apoptosis of chondrocytes in the groups treated by LRWXG decreases compared with groups treated by inhibitors alone and model group under conditions of oxidative stress in a dose-dependent manner. Mechanistically at the molecular level, LRWXG regulates the MAPK pathway induced by oxidative stress: The levels of phosphorylation of JNK and p38 proteins in the groups treated by LRWXG are lower than model group, while compared with corresponding groups of inhibitors, there are no significant difference; For other related proteins, LRWXG reduces the levels of the apoptosis-related proteins BAX and cleaved caspase-3, and increases the level of anti-apoptotic protein BCL2. In addition, LRWXG can significantly reduce the levels of inflammatory-related factors such as COX2, PEG2, TNFα and IL1β, and inhibits the expression of MMPs, increasing the content of type II collagen. The results of this research strongly suggest that LRWXG exerts its anti-apoptotic activity via regulating the MAPK signaling pathways in vitro.

Redifferentiation of Articular Chondrocytes by Hyperacute Serum and Platelet Rich Plasma in Collagen Type I Hydrogels

Matrix-assisted autologous chondrocyte transplantation (MACT) for focal articular cartilage defects often fails to produce adequate cartilage-specific extracellular matrix in vitro and upon transplantation results in fibrocartilage due to dedifferentiation during cell expansion. This study aimed to redifferentiate the chondrocytes through supplementation of blood-products, such as hyperacute serum (HAS) and platelet-rich plasma (PRP) in vitro. Dedifferentiated monolayer chondrocytes embedded onto collagen type I hydrogels were redifferentiated through supplementation of 10% HAS or 10% PRP for 14 days in vitro under normoxia (20% O₂) and hypoxia (4% O₂). Cell proliferation was increased by supplementing HAS for 14 days (p < 0.05) or by interchanging from HAS to PRP during Days 7–14 (p < 0.05). Sulfated glycosaminoglycan (sGAG) content was deposited under both HAS, and PRP for 14 days and an interchange during Days 7–14 depleted the sGAG content to a certain extent. PRP enhanced the gene expression of anabolic markers COL2A1 and SOX9 (p < 0.05), whereas HAS enhanced COL1A1 production. An interchange led to reduction of COL1A1 and COL2A1 expression marked by increased MMP13 expression (p < 0.05). Chondrocytes secreted less IL-6 and more PDGF-BB under PRP for 14 days (p < 0.0.5). Hypoxia enhanced TGF-β1 and BMP-2 release in both HAS and PRP. Our study demonstrates a new approach for chondrocyte redifferentiation.

Invalid freeze-dried platelet gel promotes wound healing

Wound healing is the curative process of tissue injury, composed of three phases: the inflammatory phase, proliferative phase, followed by the maturation cum remodeling phase. Various treatment options were previously depicted for wound healing, however a treatment that accelerates these phases would be highly valuable. Platelet aggregation at the bleeding vessels and release of various growth factors are the most promising factors that stimulates the wound healing progress. In the present study, we hypothesized that the freeze-dried platelet which were normally discarded from the blood banks due to invalidity, might be promising to accelerate the phases of wound healing. The invalid freeze-dried platelets were prepared to a gel form called invalid freeze-dried platelet gel (IF-PG), which was tested for its efficacy in a cutaneous punch wound model in rats. Mupirocin antibiotic gel was used as a bio-equivalent formulation. The wound healing phases and changes in the wound sites were determined by assessing the wound sizes, histopathological analysis, immunohistochemical staining. The re-epithelialization at the wound sites at different time intervals till the wound closure was also determined. Our results suggest the beneficial effects of IF-PG; in reducing the wound area and accelerating wound closure in the cutaneous punch wound in rats. Histopathology and immunostaining results support the improvements in the wound when treated with IF-PG, which were similar to that of mupirocin antibiotic gel. Our preliminary findings also warrant the competency of IF-PG in modulating the different phases of wound healing process. In conclusion, IF-PG might be a resourceful alternative for the wound care management, however further studies are required to validate its impact on various growth factors before proceeding to clinical studies.

The Clinical Evidence Behind Biologic Therapies Promoted at Annual Orthopaedic Meetings: A Systematic Review

PURPOSE

The purpose of this study is to systematically evaluate the available clinical data for biologic therapies promoted for articular cartilage defects and osteoarthritis of the knee at the 2016 American Orthopaedic Society for Sports Medicine Meeting (AOSSM) and the 2017 Arthroscopy Association of North America meeting (AANA).

METHODS

Our sample included all exhibitors at the 2016 AOSSM meeting and 2017 AANA meeting. All biologic products marketed at each conference were identified by reviewing exhibition booths and company websites. A systematic review of the clinical data on each product was then completed using PubMed, EMBASE, and the product's own webpage. All clinical peer-reviewed studies with level I-IV evidence were included in the study. Basic science or preclinical studies were excluded.

RESULTS

There were 16 products promoted for biologic therapy for articular cartilage defects or osteoarthritis of the knee at the AOSSM meeting and 11 products promoted at the AANA meeting. A total of 280 articles detailed clinical findings for the articular cartilage products displayed at AOSSM and AANA. Of the 280, there were 36 level I evidence studies, 37 level II evidence studies, 18 level III evidence studies, and 189 level IV evidence studies. Of these articles, 91% were for 4 products. Of all biologic products promoted at the 2 meetings, 65% did not have any peer-reviewed clinical data supporting their use.

CONCLUSION

Overall, many biologic therapies promoted at leading arthroscopy and sports medicine conferences did not have clinical evidence evaluating their use in the peer-reviewed literature. Although scientific advancement requires new technology, orthopaedic surgeons should be cautious about using biologic therapies in their practice with no proven efficacy. There are likely promising new interventions that, with additional scientific research, will be proven efficacious for our patients.

CLINICAL RELEVANCE

This article gives orthopaedic surgeons a detailed example of some of the biologic treatments being offered on the market for the treatment of knee articular cartilage disease. When patients request these treatments, physicians must be able to explain the data supporting their use.