Biologic enhancement of cartilage repair: the role of platelet-rich plasma and other commercially available growth factors

A systematic review of the outcomes of partial ulnar collateral ligament tears of the elbow in athletes treated non-operatively with platelet-rich plasma injection

Background

This study aimed to analyze the effects of platelet-rich plasma (PRP) for partial ulnar collateral ligament (UCL) tears in athletes and predicted positive outcomes.

Methods

The researchers systematically reviewed the PubMed, Cochrane CENTRAL, MEDLINE, Scopus, and Google Scholar databases to identify studies with clinical outcomes of PRP for partial UCL tears. They excluded studies that did not stratify data by tear type or included surgical management.

Results

Five studies with 156 patients were included. The timing, amount, platelet concentration, type, and number of PRP injections were highly variable among the studies. However, 75% (n = 97/127) of athletes returned to sport (RTS) at a weighted average of 82.1 days (37-84) after PRP injection. One study showed significant improvements in patient-reported outcomes. Two studies showed positive outcomes in the modified Conway scale, complete reconstitution of the UCL in 87% of patients on MRI, and significant improvement in the humeral-ulnar joint space after PRP injection via ultrasound. The Coleman methodology score (CMS) averaged 48/100, indicating an overall poor quality of evidence.

Conclusion

This review demonstrates favorable RTS, clinical, and radiographic outcomes in patients receiving PRP for partial UCL tears, but the literature remains heterogeneous and of low quality.

Level of Evidence

III.

Comparative effects of different supplemented dietary doses of chlorophyll on blood parameters of experimental male rats

Chlorophylls are organic pigments that are a part of our daily diet, particularly in light of the increased popularity of more eco-friendly and healthy practices. Since altering oxidative equilibrium seems to be connected to the emergence of numerous illnesses, the antioxidant capacities of both groups of lipophilic compounds have been studied. The objective was to evaluate adding dietary chlorophyll at two concentrations-30 and 60 mg/ml-would improve blood characteristics in rats. Supplemented dietary chlorophyll showed significantly increased WBCs, RBCs, granulocytes, lymphocytes, HGB, HCT MCHC, and Platelets. it nonsignificant effect on RDW, MPV, and Eosinophil. These findings support a significant rise in critical hematological parameters at two separate time intervals, 14 and 28 days following dietary chlorophyll supplementation, at dosages of 30 and 60 mg/ml. After 30 and 60 mg/ml, platelet count, PCT, lymphocytes, and monocytes substantially (p0.001) rose. In light of these findings, critical hematological indicators markedly rise in response to exogenous dietary chlorophyll. To strengthen blood parameters and enhance blood features and prevent anemia, dietary chlorophyll is advised.

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.

Improvement of Blood Parameters of Male Rats Exposed to Different Injection Doses of Liquid Chlorophyll

Introduction Chlorophylls are natural pigments in our everyday diet, especially with customers' rising preference for more natural and healthful habits. The antioxidant capabilities of both classes of lipophilic substances have been researched since disrupting antioxidant equilibrium appears to be linked to the development of several diseases. Methods This research aimed to evaluate the effect of injection with chlorophyll (30 and 60 mg/ml) on enhancing the blood parameters of rats. Twenty-one white male rats were included in this study and divided into three groups: control, 30 mg/ml, and 60 mg/ml.  Results Treatment with liquid chlorophyll significantly increased white blood cells (WBCs), red blood cells (RBCs), granulocytes, lymphocytes, hemoglobin (Hgb), hematocrit (Hct), mean corpuscular Hgb concentration (MCHC), and platelets. However, it nonsignificantly increased mean corpuscular volume (MCV). These results confirm a great increase in important hematological parameters in response to exogenous injectable chlorophyll with concentrations of 30 and 60 mg/ml and at two different time points, 14 and 28 days after injection. The platelet count was significantly (p<0.001) increased after 30 mg/ml and 60 mg/ml. Conclusion These results show a significant increase in important hematological parameters in response to exogenous injectable chlorophyll. The liquid chlorophyll is recommended to increase blood parameters and improve blood characteristics avoiding anemia.

Comparing the Efficacy of Intra-Articular Single Platelet-Rich Plasma(PRP) versus Novel Crosslinked Hyaluronic Acid for Early-Stage Knee Osteoarthritis: A Prospective, Double-Blind, Randomized Controlled Trial

Background and Objectives: For the treatment of knee osteoarthritis (OA), intra-articular platelet-rich plasma (PRP) and novel crosslinked single-dose hyaluronic acid (HA) have both been reported to improve outcomes, but no study has compared them for the treatment of knee OA. We hypothesized patients with early-stage knee OA who received PRP injections would have more WOMAC score changes than those who received HA injections. This is the first prospective, double-blind, parallel, randomized controlled trial comparing the efficacy of intra-articular single-dose PRP versus novel crosslinked HA (HyajointPlus) for treating early-stage knee OA. Materials and Methods: This study analyzed 110 patients randomized into the PRP (n = 54) or HA (n = 56) groups. The primary outcome is the change of WOMAC score at 1-, 3-, and 6-month follow-ups compared to baseline. Results: The data revealed significant improvements in all WOMAC scores in the PRP group at 1-, 3-, and 6-month follow-up visits compared with the baseline level except for the WOMAC stiffness score at the 1-month follow up. In the HA group, significant improvements were observed only in the WOMAC pain score for all the follow-up visits and in WOMAC stiffness, function, and total scores at 6-month follow-up. When comparing the change of WOMAC score at 1-, 3-, and 6-month follow-ups, no significant differences were found between PRP and HA group. Conclusions: This study revealed that both PRP and HA can yield significant improvements in WOMAC scores at 6-month follow-up without any between-group differences at 1-, 3-, and 6-month follow-ups. Thus, both the single-injection regimens of PRP and HA can improve the functional outcomes for treating early-stage knee OA.

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

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

Regenerative Effect of Low-Intensity Pulsed Ultrasound and Platelet-Rich Plasma on the Joint Friction and Biomechanical Properties of Cartilage: A Non-traumatic Osteoarthritis Model in the Guinea Pig

This study was aimed at investigating the effects of platelet-rich plasma (PRP) and low-intensity pulsed ultrasound (LIPUS) on the joint friction parameters and biomechanical properties of articular cartilage in a non-traumatic knee osteoarthritis (OA) model. Fifty adult male Dunkin Hartley guinea pigs were randomly divided into five groups: control, OA60, OA + US, OA + PRP and OA + US + PRP). Non-traumatic knee OA was induced with a single dose of 3 mg of mono-iodoacetate (MIA) by intra-articular injection. Intra-articular PRP was injected twice in the OA + PRP and OA + US + PRP groups. LIPUS was delivered in 10 sessions in the OA + US and OA + US + PRP groups. By use of the pendulum free oscillation test, joint friction (coefficient of friction) was measured. In addition, the instantaneous elastic modulus and aggregate modulus were measured using the stress-relaxation test. MIA injection decreased cartilage thickness, instantaneous elastic modulus and aggregate modulus, and increased joint friction. The friction coefficients in the OA + US and OA + US + PRP groups reached near-normal values, and there was no significant difference compared with the control group (p = 0.232 and p = 0.459, respectively). The instantaneous elastic modulus and aggregate modulus in the OA + US group increased significantly compared with the OA + PRP group (p < 0.05). It seems that both LIPUS and PRP injection effectively improved joint lubrication, but LIPUS was superior to PRP in improving the mechanical properties of the articular cartilage.

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.

Platelet-rich plasma treatment alleviates osteoarthritis-related pain, inflammation, and apoptosis by upregulating the expression levels of microRNA-375 and microRNA-337

OBJECTIVE

The present study was designed to determine the molecular mechanism by which platelet-rich plasma (PRP) acts on Osteoarthritis (OA) -related pain, inflammation, and apoptosis in vivo and in vitro.

MATERIALS AND METHODS

An in vivo OA model was established in rats using anterior cruciate ligament transection, and an in vitro OA model was created by treating chondrocytes with IL-1β. Then, the induced rats and chondrocytes were treated with PRP. Real-time PCR were used to examine the expression of micorRNAs (miRs) and mRNAs of inflammatory cytokines. WB were performed to detect the expression of apoptotic factors and Wnt/β-catenin signals. Structural damage of the cartilage and pain in OA rats were analyzed and represented by Mankin Score, OARSIS score, Tender threshold, and Thermal pain threshold. CCK-8 assay and flow cytometry were used to determine cell viability and apoptosis.

RESULTS

The expression levels of miR-337 and miR-375 were downregulated in the in vivo and vitro OA models; however, PRP treatment elevated their levels. miR-337 and miR-375 inhibition reversed the effects of PRP of reducing tenderness and thermal pain thresholds in OA rats. Moreover, PRP decreased the mRNA expression levels of MMP-13, Bax, and inflammatory factors, such as IL-1β, IL-18, and TNF-α, as well as increased the expression levels of collagen II and antiapoptotic Bcl-2. The decrease in inflammation and apoptosis was reversed by miR-337 and miR-375 inhibition, respectively.

DISCUSSION AND CONCLUSIONS

In conclusion, miR-337 and miR-375 are involved in PRP-delayed OA progression by affecting inflammation and apoptosis.

Identification of regeneration-involved growth factors in cartilage engineering procedure promotes its reconstruction

Aim: To fabricate mature cartilage for implantation, developmental biological processes and proteins should be understood and employed. Methods: A systems biology study of all protein-coding genes participating in cartilage regeneration resulted in a network graph with 11 nodes and 28 edges. Gene ontology and centrality analysis were performed based on the degree index. Results: The four most crucial biological processes along with the seven most interactive proteins involved in cartilage regeneration were identified. Some proteins, which are under serious discussion in cartilage developmental and disease processes, are included in regeneration. Conclusions: Findings positively correlate with the literature, supporting the use of the four most impressive proteins as growth factors applicable to cartilage tissue engineering, including COL2A1, SOX9, CTGF and TGFβ1.

Efficacy and Safety of a Single Intra-articular Injection of Platelet-rich Plasma on Pain and Physical Function in Patients With Ankle Osteoarthritis-A Prospective Study

Ankle osteoarthritis (OA) can cause disabling symptoms, and some patients prefer to be treated with minimally invasive procedures. The aim was to evaluate the efficacy and safety of a single intraarticular injection of platelet-rich plasma (PRP) for patients with ankle OA. In a prospective study done in a university-affiliated tertiary care medical center, 44 patients with symptomatic ankle OA for at least 6 months were recruited. Patients received a single injection of PRP (3 mL) into symptomatic ankles. The primary outcome was the change from baseline in the visual analog scale (VAS) pain (0-10 cm) at 6 months. Secondary outcomes included the Ankle Osteoarthritis Scale (AOS) score, American Orthopedic Foot and Ankle Society (AOFAS) hindfoot-ankle score, single-leg stance test (SLS), rescue analgesics consumption and patient satisfaction. Thirty-nine participants (88.64%) completed the study. Significantly improvement in the VAS and AOS was noted at 1-, 3-, and 6-month follow-ups (p < .001). The mean VAS pain decreased significantly from 4.1 ± 1.7 at baseline to 2.2 ± 1.9, 1.7 ± 1.5, and 1.8 ± 1.6 at 1, 3, and 6 months (p < .001). The mean total AOS score reduced by 1.5, 2.2, and 2.1 from baseline respectively postinjection (p < .001). The mean AOFAS hindfoot-ankle score improved from 80.3 points at baseline to 87.2, 91.6, and 89.7 points at 1, 3, and 6 months (p < .001). SLS tests improved significantly (p < .001) at each follow-up. Acetaminophen consumption dropped significantly (p < .001) and no serious adverse events occurred. The study showed promise for a single intraarticular injection of PRP in the treatment of ankle OA.

Injectable Scaffold for Bone Marrow Stem Cells and Bone Morphogenetic Protein-2 to Repair Cartilage

OBJECTIVE

The limits of the microfracture (MFX) treatment in terms of lesion size and long-term tissue functionality makes it necessary to investigate different alternatives to repair focal cartilage lesions. The present study aims at evaluating the efficacy of a minimally invasive approach against the conventional MFX to repair a chondral defect in rabbits. An injectable scaffold of BMP-2 pre-encapsulated in PLGA microspheres dispersed in a Pluronic F-127 solution is proposed as support of cells and controlled delivery system for the growth factor.

DESIGN

MFX was compared versus the injectable system seeded with mesenchymal stem cells (MSCs), both without BMP-2 and under controlled release of BMP-2 at 2 different doses (3 and 12 µg/scaffold). The different treatments were evaluated on a 4-mm diameter chondral defect model using 9 experimental groups of 4 rabbits (8 knees) each, throughout 24 weeks.

RESULTS

Histologically, all the treated groups, except MFX treated, responded significantly better than the control group (nontreated defect). Although no significant differences were found between the treated groups, only BMP(12), MSC-BMP(12), and MFX-BMP(3) groups showed nonsignificant differences when compared with the normal cartilage.

CONCLUSIONS

The hydrogel system proposed to control the release rate of the BMP-2 was safe, easily injectable, and also provided good support for cells. Treatments with MSCs or BMP-2 repaired efficiently the chondral lesion created in rabbits, being less invasive than MFX treatment.

Treatment of knee osteoarthritic pain with platelet-rich plasma: a systematic review of clinical studies

Introduction: Knee osteoarthritis is a degenerative joint disease that is secondary to degradation of articular cartilage, reformation of subchondral bone through degradation and proliferation as well as presence of synovitis. Materials & methods: This systematic review was conducted and reported as per Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Results: A total of 30 of the 48 comparators showed statistically significant superiority with platelet-rich plasma (PRP) compared with a control, while the other 16 comparators showed no significant difference between PRP and the comparator. Conclusion: We can only recommend PRP for patients with early-stage osteoarthritis (I or II) and who are aged below 65, based on our findings. Based on the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) recommendations, while studies reviewed were randomized controlled studies, and therefore, high grade, due to variance in imprecision, risk of bias and inconsistency among the 37 studies, it would be reasonable to rate this paper as subjectively moderate.

Return to Play After Platelet-Rich Plasma Injection for Elbow UCL Injury: Outcomes Based on Injury Severity

Background:

Ulnar collateral ligament (UCL) injuries of the elbow are uncommon in the general population but prevalent in the athletic community, particularly among baseball players. Platelet-rich plasma (PRP) injection therapy has become a popular nonoperative adjuvant treatment for such injuries to help reduce recovery time and avoid surgery.

Purpose/Hypothesis:

To analyze patient outcomes by injury severity and identify injury types that responded most favorably and unfavorably to PRP treatment. It was hypothesized that PRP therapy would prove to be most beneficial in the treatment of lower-grade, partial UCL tears and less effective in the treatment of more severe, complete UCL tears.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A cohort of 50 patients with UCL injuries in their dominant elbow, diagnosed by MRI (magnetic resonance imaging) arthrogram, underwent PRP therapy in conjunction with an established rehabilitation program. UCL injuries were classified by MRI as low-grade partial tear (Type I), high-grade partial tear (Type II), complete tear (Type III), or tear in more than 1 location (Type IV).

Results:

In total, 24 of 39 (61.5%) Type I and II tears, 3 of 3 (100%) Type III tears, and 1 of 8 (12.5%) patients with Type IV tears responded to UCL PRP injection therapy and were able to return to play without surgery. Ten patients required subsequent UCL PRP injections, of which 3 (30%) were able to return to sport without surgery.

Conclusion:

PRP treatment for Types I and II UCL tears shows great promise when combined with physical therapy and a rehabilitation program. Type III UCL tears demonstrated a high rate of success, although with low cohort numbers. Type IV UCL tears did not appear to respond well to PRP injection therapy and often required surgical intervention or cessation of sport. Therefore, PRP treatment does not appear to be appropriate for patients with complete Type IV UCL tears but may enhance recovery and improve outcomes in throwing athletes with Types I, II, and III UCL injuries.

Comparing efficacy of intraarticular single crosslinked Hyaluronan (HYAJOINT Plus) and platelet-rich plasma (PRP) versus PRP alone for treating knee osteoarthritis

Intraarticular hyaluronan or platelet-rich plasma (PRP) is widely used in the treatment of knee osteoarthritis (OA). The efficacy of combined hyaluronan with PRP remained inconclusive. This study aimed to investigate the efficacy of combined a single crosslinked hyaluronan (HYAJOINT Plus) and a single PRP versus a single PRP in patients with knee OA. In a prospective randomized-controlled trial, 85 patients with knee OA (Kellgren-Lawrence 2) were randomized to receive a single intraarticular injection of HYAJOINT Plus (3 ml, 20 mg/ml) followed by 3 ml PRP (the combined-injection group, N = 43) or a single injection of 3 ml PRP (the one-injection group, N = 42). The primary outcome was the change from baseline in the visual analog scale (VAS) pain (0–00 mm) at 6 months. Secondary outcomes included The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC, Likert Scale), Lequesne index, single leg stance test (SLS), use of rescue analgesics and patient satisfaction at 1, 3 and 6 months. Seventy-eight patients were available for the intention-to-treat analysis at 6 months. Both groups improved significantly in VAS pain, WOMAC, Lequesne index and SLS at each follow-up visit (p < 0.001). Patients receiving a single PRP experienced significantly greater improvements in VAS pain than patients receiving combined injections at 1-month follow-up (adjusted mean difference: − 5.6; p = 0.017). There were no significant between-group differences in several of the second outcomes at each follow-up visit, except the WOMAC-pain and WOMAC-stiffness scores favoring the one-injection group at 1 month (p = 0.025 and p = 0.011). However, at 6-month follow-up, the combined-injection group achieved significantly better VAS pain reduction (p = 0.020). No serious adverse events occurred following injections. In conclusion, either combined injections of HYAJOINT Plus and PRP or a single PRP alone was safe and effective for 6 months in patients with Kellgren-Lawrence 2 knee OA. Combined injections of HYAJOINT Plus and PRP achieved better VAS pain reduction than a single PRP at 6 months. The results indicating a long term benefit effect of a combination of HYAJOINT Plus and PRP in a particular subset of patients with moderate knee OA need to be replicated in larger trials.

ClinicalTrials.gov number NCT04315103.

Intra-Articular Mesenchymal Stromal Cell Injections Are No Different From Placebo in the Treatment of Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

PURPOSE

To evaluate the efficacy and safety of intra-articular mesenchymal stromal cells (MSCs) injections for knee osteoarthritis (OA) treatment.

METHODS

We performed a systematic literature search in PubMed, Embase, Scopus, and the Cochrane Library through April 2020 to identify level I randomized controlled trials (RCTs) that evaluated the clinical efficacy of MSCs versus control treatments for knee OA. Outcomes were analyzed on an intention-to-treat basis with random-effects models.

RESULTS

A total of 13 RCTs were included in the meta-analysis. Compared with placebo, there was no significant difference in VAS for pain (mean difference [MD] 1.62, 95% confidence interval [CI -0.60 to 3.85), WOMAC pain score (MD 1.88, 95% CI -0.21 to 3.98), WOMAC function score (MD -0.67, 95% CI -6.54 to 5.19), or WOMAC stiffness score (MD 0.64, 95% CI -0.86 to 2.14) for MSCs. Moreover, the smallest treatment effect of VAS for pain, WOMAC pain score, WOMAC function score, and WOMAC stiffness score did not exceed the minimum clinically important difference (MCID). Additionally, there was no significant difference in percentage of patients crossing the MCID threshold between MSC and placebo groups for VAS for pain (relative risk [RR] 0.93, 95% CI 0.55 to 1.57) or WOMAC total score (RR 0.40, 95% CI 0.13 to 1.21). Compared with hyaluronic acid (HA), MSC injection was associated with significantly better improvement in VAS for pain (MD 2.00, 95% CI 0.94 to 3.07), WOMAC pain score (MD 4.58, 95% CI 0.49 to 8.67), WOMAC total score (MD 14.86, 95% CI 10.59 to 19.13), and WOMAC stiffness score (MD 1.85, 95% CI 0.02 to 3.69). However, the smallest treatment effect of VAS for pain, WOMAC pain score, WOMAC function score, and WOMAC stiffness score did not exceed the MCID. Moreover, there was no significant difference in percentage of patients crossing the MCID threshold between MSC and HA groups for WOMAC total score (RR 0.57, 95% CI 0.21 to 1.55). We also found that MSCs did not increase adverse events compared with HA and placebo.

CONCLUSIONS

Intra-articular MSC injection was not found to be superior to placebo in pain relief and functional improvement for patients with symptomatic knee OA. However, additional direct testing and combination trials of different type of cells, doses, and number of injections of MSCs are required to further enhance clinical decision making for people with symptomatic knee OA.

LEVEL OF EVIDENCE

I, meta-analysis of level I studies.

Leucocyte-poor-platelet-rich plasma intra-operative injection in chondral knee injuries improve patients outcomes. A prospective randomized trial

PURPOSE

Evaluate the effects of intra-operative leucocyte-poor-platelet-rich plasma (PRP) (type P3-Bβ with endogenous activation) injection in International Cartilage Repair Society (ICRS) grade III knee chondral injuries treated by chondroplasties, to increase and ameliorate the repair tissue.

METHODS

Patients were divided into two groups. Group A (control) consisted of 31 patients and Group B (PRP) 33 patients, totaling 64 patients analyzed. Patients also could had associated injuries (meniscal and/or ACL) being equally divided between both groups to avoid bias. PRP was injected at the end of surgery in group B. The patient outcomes were assessed using subjective International Knee Documentation Committee (IKDC) form, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Tegner activity forms, prior to the surgery and three, six, 12, and 24 months after surgery (medium-term follow up).

RESULTS

IKDC and KOOS scores showed increase at each evaluation time points after surgery in both groups, but the treated Group (B) showed a higher increase with statistically significant difference. The Tegner activity scores were higher for the treated group only at six and 12 months.

CONCLUSION

Based on the subjective IKDC, KOOS, and Tegner scores, those patients affected by ICRS grade III chondral injuries undergoing arthroscopic chondroplasty who were also treated with PRP showed better and faster outcomes than the control group. Independently from the associated injury (meniscal or ACL). This difference could be measured for up to two years.

Meta-analysis Comparing Platelet-Rich Plasma vs Hyaluronic Acid Injection in Patients with Knee Osteoarthritis

PURPOSE

The purpose of this meta-analysis was to compare platelet-rich plasma (PRP) and hyaluronic acid (HA) in patients with knee osteoarthritis (KOA).

METHODS

Randomized controlled trials (RCTs) comparing the use of PRP and HA in KOA patients were retrieved from each database from the establishment date to April 2018. Outcome measurements were the Western Ontario and McMaster Universities Arthritis Index (WOMAC), visual analog scale (VAS), International Knee Documentation Committee, and Lequesne Index scores and adverse events. The pooled data were evaluated with Review Manager 5.3.5.

RESULTS

Fifteen RCTs (N = 1,314) were included in our meta-analysis. The present meta-analysis indicated that PRP injections reduced pain more effectively than HA injections in patients with KOA at six and 12 months of follow-up, as evaluated by the WOMAC pain score; the VAS pain score showed a significant difference at 12 months. Moreover, better functional improvement was observed in the PRP group, as demonstrated by the WOMAC function score at three, six, and 12 months. Additionally, PRP injections did not display different adverse event rates compared with HA injections.

CONCLUSION

In terms of long-term pain relief and functional improvement, PRP injections might be more effective than HA injections as a treatment for KOA. The optimal dosage, the timing interval and frequency of injections, and the ideal treatment for different stages of KOA remain areas of concern for future investigations.

Comparison of the short-term results of single-dose intra-articular peptide with hyaluronic acid and platelet-rich plasma injections in knee osteoarthritis: a randomized study

Introduction/objectives

Intra-articular injections may be useful in terms of pain and functional status, in knee osteoarthritis (OA). Besides hyaluronic acid (HA) and platelet-rich plasma (PRP), peptide molecules recently begin to be used. The aim of this study was to compare the efficacy of intra-articular peptide Prostrolane® (CAREGEN Co. Ltd.) injection with that of the HA and PRP in the persons with OA.

Method

Fifty-four patients with OA were included in this prospective, randomized study. Patients were randomized into three groups as intra-articular HA, peptide, and PRP groups. Paracetamol was permitted three times a day to all groups. All the patients were evaluated by the Western Ontario and McMaster Universities Arthritis Index (WOMAC), Health Assessment Questionnaire (HAQ), and visual analogue scale (VAS) at rest and during movements. Measurements performed at the baseline, after the first week of injection, and at the first and third months of follow-up.

Results

Mean age was 55.8 ± 8.9 years. Forty-four (81.6%) were women. A week after the injections, rest and movement pain severity was measured by VAS decreased significantly in all the study groups (p < 0.05). There were no statistically significant differences between the groups in terms of first week pain relief (p > 0.05). WOMAC pain, stiffness, function, and total scores were improved significantly in all the groups a week after the injections (p < 0.05). Improvement continued at the third month control; however, the improvement in the WOMAC pain score was significantly better in the peptide group at the third month control (p < 0.05). The decrease in the rest and movement pain was continued for 3 months except the HA group’s rest pain. There were no differences among the groups for all measurements, except for the WOMAC pain score at 3 months after treatment, which was significantly lower in the peptide group.

Conclusion

As a result, pain relief and functional improvement were obtained after the intra-articular HA, peptide, and PRP injections in OA, and decrease in pain was better in the peptide group.

Key Points • The short-term effects of intra-articular HA, peptide, and PRP injections were compared in knee osteoarthritis. • HA, peptide, and PRP injections may be useful in pain relief and functional improvement in knee osteoarthritis.

Exosomes derived from platelet-rich plasma present a novel potential in alleviating knee osteoarthritis by promoting proliferation and inhibiting apoptosis of chondrocyte via Wnt/β-catenin signaling pathway

Background

Platelet-rich plasma (PRP) provides a nonsurgical approach for treating osteoarthritis (OA). Exosomes that play vital roles in intercellular communication have been studied extensively. Here, we investigated the therapeutic potential and molecular mechanism of exosomes derived from PRP (PRP-Exos) in alleviating OA.

Methods

Exosomes derived from PRP(PRP-Exos) were isolated and purified using the exoEasy Maxi Kit and then identified and analyzed. Primary rabbit chondrocytes were isolated and treated with interleukin 1 beta (IL-1β) to establish the OA model in vitro. Proliferation, migration, and apoptosis assays were measured and compared between PRP-Exos and activated PRP (PRP-As) to evaluate the therapeutic effects on OA. The mechanism involving the Wnt/β-catenin signaling pathway was investigated by Western blot analysis. In vivo, we established animal knee OA model by surgery to compare the therapeutic effect of PRP-Exos and PRP-As.

Results

We successfully isolated and purified exosomes from PRP using the exoEasy Maxi Kit. We also isolated and identified chondrocytes from the New Zealand white rabbit and established the IL-1β-induced OA model; meanwhile, PRP-Exos and PRP-As both inhibited the release of tumor necrosis factor-α(TNF-α) and there was no statistically significant difference between the two. In proliferation, migration, scratch assay, the promoting effect of PRP-Exos was significantly more better than PRP-As. Furthermore, PRP-Exos could significantly decreased apoptotic rate of OA chondrocyte compared with PRP-As. In Western blot analysis, the expression of β-catenin, and RUNX2, Wnt5a were increased in IL-1β-treated chondrocytes, but PRP-Exos and PRP-As could both reverse these changes, and the reversal effect of the former was better than the latter. In vivo, we found that both PRP-Exos and PRP-As displayed the progression of OA, and the effect of PRP-Exos was obviously better than PRP-As by chondrocyte count and Osteoarthritis Research Society International (OARSI) scoring system.

Conclusion

The therapeutic effects of PRP-Exos on OA were similar or better compared with those of PRP-As in vitro or in vivo. PRP-Exos acting as carriers containing growth factors derived from PRP present a novel therapy for OA by activating the Wnt/β-catenin signaling pathway.

Reflex arc recovery after spinal cord dorsal root repair with platelet rich plasma (PRP)

Spinal dorsal roots can be affected by a wide range of lesions, leading to a significant loss of proprioceptive information transmission and greatly affecting motor behavior. In this context, the reimplantation of lesioned roots with platelet-rich plasma (PRP) may allow nerve regeneration. Therefore, the present study evaluated sensorimotor improvement following dorsal root rhizotomy and repair with PRP. For this purpose, female Lewis rats were subjected to unilateral rhizotomy (RZ) of the L4-L6 dorsal roots and divided into the following groups: (1) the unlesioned control group; (2) the group that underwent rhizotomy (RZ) without repair; and (3) the group that underwent RZ followed by root repair with PRP. PRP was obtained from human blood and characterized regarding platelet concentration, integrity, and viability. Reflex arc recovery was evaluated weekly for eight weeks by the electronic von Frey method. The spinal cords were processed 1 week postlesion to evaluate the in vivo gene expression of TNFα, TGF-β, BDNF, GDNF, VEGF, NGF, IL-4, IL-6, IL-13 by qRT-PCR and eight weeks postlesion to evaluate changes in the glial response (GFAP and Iba-1) and excitatory synaptic circuits (VGLUT1) by immunofluorescence. The results indicated that PRP therapy partially restores the paw withdrawal reflex over time, indicating the reentry of primary afferents from the dorsal root ganglia into the spinal cord without exacerbating glial reactivity. Additionally, the analysis of mRNA levels showed that PRP therapy has immunomodulatory properties. Overall, the present data suggest that the repair of dorsal roots with PRP may be considered a promising approach to improve sensorimotor recovery following dorsal rhizotomy.

Comparison of platelet-rich plasma vs hyaluronic acid injections in patients with knee osteoarthritis: A protocol for a systematic review and meta-analysis

BACKGROUND

Knee osteoarthritis (KOA) is a progressive joint disease involving intraarticular and periarticular structures. In recent years, there has been increasing interest in the use of autologous growth factors, such as intraarticular injections of platelet-rich plasma (PRP), to treat KOA. It is necessary to update the research and reevaluate the efficacy and safety of PRP to provide up-to-date evidence for KOA management. Therefore, we provide a protocol for a systematic review of PRP for KOA.

METHODS

The aim of this study was to retrieve papers on the topic of PRP treatment for KOA in electronic databases including PubMed, Embase, and the Cochrane Library. The search will include studies that were published from the time the databases were established until April 2018. The entire process will include study selection, data extraction, risk of bias assessment, and meta-analyses.

RESULTS

The literature will provide a high-quality analysis of the current evidence supporting PRP for KOA based on various comprehensive assessments including the Western Ontario and McMaster Universities Osteoarthritis Index, visual analog scale scores, International Knee Documentation Committee scores, Lequesne index scores, and adverse events.

CONCLUSION

This proposed systematic review will provide up-to-date evidence to assess the effect of PRP treatment for patients with KOA.

PROSPERO REGISTRATION NUMBER

CRD42018108825.

Comparative efficacy and safety of oral or transdermal opioids in the treatment of knee or hip osteoarthritis: a systematic review and Bayesian network meta-analysis protocol

INTRODUCTION

Osteoarthritis is a common degenerative joint disease that eventually leads to disability and poor quality of life. The main symptoms are joint pain and mobility disorders. If the patient has severe pain or other analgesics are contraindicated, opioids may be a viable treatment option. To evaluate and compare the efficacy and safety of opioids in the treatment of knee or hip osteoarthritis, we will integrate direct and indirect evidence using a Bayesian network meta-analysis to establish hierarchies of these drugs.

METHODS AND ANALYSIS

We will search the Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, Web of Science and PsycINFO databases as well as published and unpublished research in international registries and regulatory agency websites for osteoarthritis reports published prior to 5 January 2018. There will be no restrictions on the language. Randomised clinical trials that compare oral or transdermal opioids with other various opioids, placebo or no treatment for patients with knee or hip osteoarthritis will be included. The primary outcomes of efficacy will be pain and function. We will use pain and function scales to evaluate the main outcomes. The secondary outcomes of safety will be defined as the proportion of patients who have stopped treatment due to side effects. Pairwise meta-analyses and Bayesian network meta-analyses will be performed for all related outcome measures. We will conduct subgroup analyses and sensitivity analyses to assess the robustness of our findings. The Grading of Recommendations, Assessment, Development and Evaluations framework will be used to assess the quality of the evidence contributing to each network assessment.

ETHICS AND DISSEMINATION

This study does not require formal ethical approval because individual patient data will not be included. The findings will be disseminated through peer-reviewed publications or conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42018085503.

Effects of intravesical therapy with platelet-rich plasma (PRP) and Bacillus Calmette-Guérin (BCG) in non-muscle invasive bladder cancer

This study describes the effects of a promising therapeutic alternative for non-muscle invasive bladder cancer (NMIBC) based on Bacillus Calmette-Guerin (BCG) intravesical immunotherapy combined with Platelet-rich plasma (PRP) in an animal model. Furthermore, this study describes the possible mechanisms of this therapeutic combination involving Toll-like Receptors (TLRs) 2 and 4 signaling pathways. NMIBC was induced by treating female Fischer 344 rats with N-methyl-N-nitrosourea (MNU). After treatment with MNU, the animals were distributed into four experimental groups: Control (without MNU) group, MNU (cancer) group, MNU + PRP group, MNU + BCG group and MNU + PRP + BCG group. Our results demonstrated that PRP treatment alone or associated with BCG triggered significant cytotoxicity in bladder carcinoma cells (HTB-9). Animals treated with PRP associated to BCG clearly showed better histopathological recovery from the cancer state and decrease of urothelial neoplastic lesions progression in 70% of animals when compared to groups that received the same therapies administered singly. In addition, this therapeutic association led to distinct activation of immune system TLRs 2 and 4-mediated, resulting in increased MyD88, TRIF, IRF3, IFN-γ immunoreactivities. Taken together, the data obtained suggest that interferon signaling pathway activation by PRP treatment in combination with BCG immunotherapy may provide novel therapeutic approaches for non-muscle invasive bladder cancer.

Avascular Necrosis of the Femoral Head

About 250000 patients are operated on annually for hip arthroplasty in the USA alone. Of this number, about 10% the cause of their osteoarthritis is the avascular necrosis of the femoral head. But the causes of necrosis are multiple and many of them are still unknown. That is why small advances in etiopathogenesis, diagnosis and treatment of different causes are very important in order to reduce the number of affected patients. It may seem that small changes, studies focused on the details of different diseases do not bring great changes to science, but it is these small changes that end up adding great evolutions in our knowledge. In addition, the changes of recent years, are not focused on our specialty in technical or anatomical evolutions exclusively, but are often based on biological bases, which is the branch that evolves more within trauma and orthopedics. That is why open and constant minds are what help us move forward.

Intra-articular platelet-rich plasma injections for knee osteoarthritis: An overview of systematic reviews and risk of bias considerations

OBJECTIVES

Numerous systematic reviews investigating the efficacy of platelet-rich plasma (PRP) in treating knee osteoarthritis (OA) have been recently published. The purpose of the present study was (1) to perform an overview of overlapping systematic reviews investigating PRP for knee OA via evaluating methodological quality and risk of bias of systematic reviews and (2) to provide recommendations through the best evidence.

METHODS

A systematic search of systematic reviews published through Feb 2017 was conducted using the MEDLINE, EMBASE and Cochrane Library. The methodological quality and risk of bias of included systematic reviews were assessed by AMSTAR instrument and ROBIS tool respectively. Best evidence choice procedure was conducted according to the Jadad decision algorithm. The systematic reviews with high quality of methodology and low risk of bias were selected ultimately.

RESULTS

Ten systematic reviews were eligible for inclusion. The Jadad decision making tool suggested that the reviews with highest AMSTAR score should be selected. According to the ROBIS tool, there were 4 systematic reviews with low risk of bias and 6 with high risk of bias. As a result, two systematic reviews conducted by Dai et al and Meheux et al with highest AMSTAR score and low risk of bias were selected as the best evidence.

CONCLUSIONS

The present overview demonstrates that PRP is an effective intervention in treating knee OA without increased risk of adverse events. Therefore, the present conclusions may help decision makers interpret and choose PRP with more confidence.

Efficacy of Platelet-Rich Plasma in the Treatment of Knee Osteoarthritis: A Meta-analysis of Randomized Controlled Trials

PURPOSE

To use meta-analysis techniques to evaluate the efficacy and safety of platelet-rich plasma (PRP) injections for the treatment knee of osteoarthritis (OA).

METHODS

We performed a systematic literature search in PubMed, Embase, Scopus, and the Cochrane database through April 2016 to identify Level I randomized controlled trials that evaluated the clinical efficacy of PRP versus control treatments for knee OA. The primary outcomes were Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores. The primary outcomes were compared with their minimum clinically important differences (MCID)-defined as the smallest difference perceived as important by the average patient.

RESULTS

We included 10 randomized controlled trials with a total of 1069 patients. Our analysis showed that at 6 months postinjection, PRP and hyaluronic acid (HA) had similar effects with respect to pain relief (WOMAC pain score) and functional improvement (WOMAC function score, WOMAC total score, International Knee Documentation Committee score, Lequesne score). At 12 months postinjection, however, PRP was associated with significantly better pain relief (WOMAC pain score, mean difference -2.83, 95% confidence interval [CI] -4.26 to -1.39, P = .0001) and functional improvement (WOMAC function score, mean difference -12.53, 95% CI -14.58 to -10.47, P  < .00001; WOMAC total score, International Knee Documentation Committee score, Lequesne score, standardized mean difference 1.05, 95% CI 0.21-1.89, P = .01) than HA, and the effect sizes of WOMAC pain and function scores at 12 months exceeded the MCID (-0.79 for WOMAC pain and -2.85 for WOMAC function score). Compared with saline, PRP was more effective for pain relief (WOMAC pain score) and functional improvement (WOMAC function score) at 6 months and 12 months postinjection, and the effect sizes of WOMAC pain and function scores at 6 months and 12 months exceeded the MCID. We also found that PRP did not increase the risk of adverse events compared with HA and saline.

CONCLUSIONS

Current evidence indicates that, compared with HA and saline, intra-articular PRP injection may have more benefit in pain relief and functional improvement in patients with symptomatic knee OA at 1 year postinjection.

LEVEL OF EVIDENCE

Level I, meta-analysis of Level I studies.

The temporal effect of platelet-rich plasma on pain and physical function in the treatment of knee osteoarthritis: systematic review and meta-analysis of randomized controlled trials

Background

Quite a few randomized controlled trials (RCTs) investigating the efficacy of platelet-rich plasma (PRP) for treatment of knee osteoarthritis (OA) have been recently published. Therefore, an updated systematic review was performed to evaluate the temporal effect of PRP on knee pain and physical function.

Methods

Pubmed, Embase, Cochrane library, and Scopus were searched for human RCTs comparing the efficacy and/or safety of PRP infiltration with other intra-articular injections. A descriptive summary and quality assessment were performed for all the studies finally included for analysis. For studies reporting outcomes concerning Western Ontario and McMaster Universities Arthritis Index (WOMAC) or adverse events, a random-effects model was used for data synthesis.

Results

Fourteen RCTs comprising 1423 participants were included. The control included saline placebo, HA, ozone, and corticosteroids. The follow-up ranged from 12 weeks to 12 months. Risk of bias assessment showed that 4 studies were considered as moderate risk of bias and 10 as high risk of bias. Compared with control, PRP injections significantly reduced WOMAC pain subscores at 3, 6, and 12 months follow-up (p = 0.02, 0.004, <0.001, respectively); PRP significantly improved WOMAC physical function subscores at 3, 6, and 12 months (p = 0.002, 0.01, <0.001, respectively); PRP also significantly improved total WOMAC scores at 3, 6 and 12 months (all p < 0.001); nonetheless, PRP did not significantly increased the risk of post-injection adverse events (RR, 1.40 [95% CI, 0.80 to 2.45], I² = 59%, p = 0.24).

Conclusions

Intra-articular PRP injections probably are more efficacious in the treatment of knee OA in terms of pain relief and self-reported function improvement at 3, 6 and 12 months follow-up, compared with other injections, including saline placebo, HA, ozone, and corticosteroids.

Review registration

PROSPERO CRD42016045410. Registered 8 August 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13018-017-0521-3) contains supplementary material, which is available to authorized users.

Editorial Commentary: The Promise of Platelet-Rich Plasma

Platelet-rich plasma is not a panacea, but platelet-rich plasma is an effective treatment for knee osteoarthritis.

Editorial Commentary: Platelet-Rich Plasma Improves Knee Pain and Function in Patients With Knee Osteoarthritis

Systematic review of overlapping meta-analyses shows that platelet-rich plasma improves knee pain and function in patients with knee osteoarthritis. Ultimately, biologics hold promise for chondroprotection in addition to symptomatic relief.

Editorial Commentary: Effects of PRP on Cartilage Repair Using Scaffolds Are Inconclusive

Effects of PRP on cartilage repair using scaffolds are, in the clinical setting, inconclusive. Biologics research is confounded by the variety and heterogeneity of stem cells, scaffolds, PRP preparations, other growth factors, and other biological stimulants.

Editorial commentary: platelet-rich plasma in ACL surgery

Current literature does not suggest that PRP treatment improves ACL clinical outcomes. However, PRP preparations are heterogeneous, and PRP clinical investigation is affected by an infinite number of confounding variables. In addition, PRP is but one type of biologic stimulant. PRP may have benefits for ACL surgery, but clinical evidence is in its infancy.

Editorial commentary: meniscal allograft yields acceptable outcomes (for a salvage procedure)

Meniscal allograft, for proper indications, shows adequate outcomes (for a salvage procedure). Addition of biologics (growth factors and cells) may improve future outcomes, and ultimately a tissue-engineered solution is anticipated, but in the end, host articular cartilage pathology may be a significant confounder of outcome.

Editorial commentary: collagen meniscal scaffolds

Small collagen meniscal scaffolds are a treatment for partial meniscectomy, which is clinically much more common than subtotal or total meniscectomy. The scaffold alone shows promising results, but readers must be mindful of risk of bias in the literature. Addition of stem cells and growth factors is the next step in meniscal tissue engineering.

Editorial commentary: biologic enhancement of muscle and tendon healing

Review of biologic enhancement of muscle and tendon healing reveals substantial clinical study of platelet rich plasma, but an inadequate basis for evidence-based treatment recommendations. In this context, the literature shows that augmentation of rotator cuff repair is not shown to be of benefit, while treatment of knee and ankle tendinopathy and plantar fasciitis shows positive results.

Editorial commentary: healing requires scaffolds, growth factors, and cells

Fracture biology healing requires scaffolds, growth factors, and cells. Biologics definitions are clarified in terms of osteoconductivity, osteoinductivity, and osteogenesis.

Editorial commentary: autologous platelet-rich plasma

Autologous platelet-rich plasma (PRP) is promising for osteoarthritis pain and may effect cartilage repair. Platelets are growth factor factories. Commercially available PRP is heterogeneous.

Editorial commentary: arthritis treatments for pain

Arthritis treatment must be analyzed with regard to outcome. Pain is one important outcome measure. Pain relief is variable among individual patients; individually discerning, personalized, or precision medical indications for nonsurgical treatment of osteoarthritis must be more specifically determined.

Editorial commentary revisited and the spin move refined

First, editorial commentary: editorial commentary may be educational and may be controversial, but above all else, authors come first. Second, The Spin Move: The Spin Move is effective, cost-effective, and ubiquitous because, while many techniques are specific to a single joint, The Spin Move can be performed as a part of any arthroscopic and related procedure. However, like many advanced procedures, The Spin Move, when poorly executed, entails substantial risk. Preoperative planning is essential, and The Spin Move must be reviewed by inexperienced practitioners, in detailed text, figures tables, and video, at www.arthroscopytechniques.org. Practice makes perfect.