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

Platelet-rich plasma for tendinopathy and osteoarthritis: a narrative review

Background

Musculoskeletal disorders include a wide range of degenerative and inflammatory problems, which can affect any part of the muscular and skeletal system. Platelet-rich plasma (PRP) has been a breakthrough in musculoskeletal medicine, especially with its effects to speed up soft tissue, cartilage, and bone healing. It is now thought that stem cells are able to reverse the degenerative process and promote rapid healing. Platelet-rich plasma (PRP) has received special attention in treating tendinopathy and osteoarthritis. This review aims to do a comprehensive review of the scientific evidence for the efficiency of PRP application in tendinopathy and osteoarthritis.

Main body of the abstract

In osteoarthritis treatment, platelet-rich plasma is thought to influence the whole joint environment by increasing chondrocyte proliferation. The injection of autologous PRP into the joint space and surrounding soft tissues delivers a concentrated dose of these growth factors, which accelerate the healing process and reduce pain.

Short conclusion

Many studies report some benefits in regard to pain and functionality, especially in tendinopathy, but further investigations are needed to incorporate PRP into clinical practice and be a common form of therapy for tendinopathy and osteoarthritis. Caution should be applied with any treatment we use in clinical practice, especially with PRP and other forms of injections.

Back to the Future: From Appendage Development Toward Future Human Hair Follicle Neogenesis

Hair disorders such as alopecia and hirsutism often impact the social and psychological well-being of an individual. This also holds true for patients with severe burns who have lost their hair follicles (HFs). HFs stimulate proper wound healing and prevent scar formation; thus, HF research can benefit numerous patients. Although hair development and hair disorders are intensively studied, human HF development has not been fully elucidated. Research on human fetal material is often subject to restrictions, and thus development, disease, and wound healing studies remain largely dependent on time-consuming and costly animal studies. Although animal experiments have yielded considerable and useful information, it is increasingly recognized that significant differences exist between animal and human skin and that it is important to obtain meaningful human models. Human disease specific models could therefore play a key role in future therapy. To this end, hair organoids or hair-bearing skin-on-chip created from the patient’s own cells can be used. To create such a complex 3D structure, knowledge of hair genesis, i.e., the early developmental process, is indispensable. Thus, uncovering the mechanisms underlying how HF progenitor cells within human fetal skin form hair buds and subsequently HFs is of interest. Organoid studies have shown that nearly all organs can be recapitulated as mini-organs by mimicking embryonic conditions and utilizing the relevant morphogens and extracellular matrix (ECM) proteins. Therefore, knowledge of the cellular and ECM proteins in the skin of human fetuses is critical to understand the evolution of epithelial tissues, including skin appendages. This review aims to provide an overview of our current understanding of the cellular changes occurring during human skin and HF development. We further discuss the potential implementation of this knowledge in establishing a human in vitro model of a full skin substitute containing hair follicles and the subsequent translation to clinical use.

Efficacy and safety of thunder-fire moxibustion for patients with knee osteoarthritis: A protocol for systematic review and meta-analysis

BACKGROUND

Knee osteoarthritis (KOA) is a major public health issue because it causes pain and functional limitation in patients. Many studies have reported that moxibustion, a treatment in traditional Chinese medicine, is effective in treating KOA. The aim of this protocol is to develop a standard in advance for synthesize and assess the efficacy and safety of thunder-fire moxibustion for KOA from these randomized controlled trial.

METHODS

The 2 commentators will screen 7 databases (PubMed, EMBASE, the Cochrane Library, Chinese National Knowledge Infrastructure, Chinese VIP Information, Wanfang Database, and Chinese Biomedical Literature Database) for randomized controlled trials that can be included from the time the database is built up until publication in December 2020. The original study that randomized control trials of thunder-fire moxibustion for patients with KOA will be selected and is not limited by country or language. In addition, researches in progress, the reference lists, and the citation lists of identified publications will be retrieved similarly. Study selection, data extraction, and assessment of the quality will be performed independently by 2 reviewers who have been trained before data extraction. A meta-analysis will be conduct if the quantity and quality of the original studies included are satisfactory; otherwise, a descriptive analysis will be conducted. Review Manager 5.4 software (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark) will be using for data synthesis and assessment the risk of bias according to Cochrane Handbook.

RESULT

This study will provide a comprehensive review of current evidence for the treatment of thunder-fire moxibustion on KOA.

CONCLUSION

The conclusion of this study will provide a judging basis that whether the treatment of KOA with thunder-fire moxibustion is effective.

REGISTRATION NUMBER

INPLASY2020100012.

From Pathogenesis to Therapy in Knee Osteoarthritis: Bench-to-Bedside

Osteoarthritis (OA) is currently the most widespread musculoskeletal condition and primarily affects weight-bearing joints such as the knees and hips. Importantly, knee OA remains a multifactorial whole-joint disease, the appearance and progression of which involves the alteration of articular cartilage as well as the synovium, subchondral bone, ligaments, and muscles through intricate pathomechanisms. Whereas it was initially depicted as a predominantly aging-related and mechanically driven condition given its clear association with old age, high body mass index (BMI), and joint malalignment, more recent research identified and described a plethora of further factors contributing to knee OA pathogenesis. However, the pathogenic intricacies between the molecular pathways involved in OA prompted the study of certain drugs for more than one therapeutic target (amelioration of cartilage and bone changes, and synovial inflammation). Most clinical studies regarding knee OA focus mainly on improvement in pain and joint function and thus do not provide sufficient evidence on the possible disease-modifying properties of the tested drugs. Currently, there is an unmet need for further research regarding OA pathogenesis as well as the introduction and exhaustive testing of potential disease-modifying pharmacotherapies in order to structure an effective treatment plan for these patients.

Therapy of antigen-induced arthritis of the temporomandibular joint via platelet-rich plasma injections in domestic pigs

The aim of this animal study was to investigate the effect of platelet-rich plasma (PRP) injections into the temporomandibular joint (TMJ) to treat antigen-induced arthritis AIA. AIA was induced via the application of bovine serum albumin (BSA) into the TMJ. Clear histological signs and protein analysis results indicating inflammation of the TMJ were observed. Afterwards, two PRP injections were performed over an interval of 2 weeks. Concentration levels of the proinflammatory cytokines IL-1β (PRP: 33.7 ± 5.6 pg/mg, untreated: 50.0 ± 2.9 pg/mg; p = 0.04) and TNF-α (PRP: 20.7 ± 2.5 pg/mg, untreated: 31.4 ± 2.7 pg/mg; p = 0.03) were significantly decreased in the PRP-treated joints. A significant reduction in signs of histological inflammation, such as hyperplasia of the synovial membrane, leucocyte infiltration, cartilage surface alterations, and an increase in cartilage-specific glycosaminoglycan content, was observed. This animal study supports the understanding of the underlying effects of PRP treatment in the TMJ, and may enhance novel PRP therapies in the future.

Intra-Articular Injections in Knee Osteoarthritis: A Review of Literature

Knee osteoarthritis (OA) is a chronic, degenerative, and progressive disease of articular cartilage, producing discomfort and physical disability in older adults. Thirteen percent of elderly people complain of knee OA. Management options for knee OA could be divided into the following categories: conservative, pharmacological, procedural, and surgical. Joint replacement is the gold standard, reserved for severe grades of knee OA, due to its complications rate and increased risk of joint revision. A nonsurgical approach is the first choice in the adult population with cartilage damage and knee OA. Yearly, more than 10% of knee OA-affected patients undergo intra-articular injections of different drugs, especially within three months after OA diagnosis. Several molecules, such as corticosteroids injection, hyaluronic acid (HA), and platelet-rich plasma (PRP), are managed to reduce the symptoms of patients with knee OA. The aim of this review was to offer an overview of intra-articular injections used for the treatment of OA and report the conventional pharmacological products used.

Regenerative Injectable Therapies: Current Evidence

Regenerative medicine is a growing field of musculoskeletal treatments that focuses on amplifying the body's natural healing properties to improve function and pain after injury. Regenerative treatments are applied locally at the site of injury and work though different mechanisms, some of which are unexplained at this time. Current evidence demonstrates benefit for certain regenerative treatments, but further standardization of treatments and additional studies are required to provide additional data to support specific regenerative treatments. This review seeks to explore the evidence and discuss appropriate use of the most common regenerative treatments including platelet-rich plasma, prolotherapy, autologous mesenchymal stem cells, human-derived allograft products, and saline.

3D composite engineered using supercritical CO2 decellularized porcine cartilage scaffold, chondrocytes, and PRP: Role in articular cartilage regeneration

At present, no definitive treatment for articular cartilage defects has been perfected. Most of the previous treatments involved multiple drilling and microfracture over defect sites with repair-related substances, which poses a limited therapeutic effect. End-stage therapy includes artificial knee joint replacement. In this study, we prepared a novel decellularized natural cartilage scaffold from porcine articular cartilage by supercritical CO₂ extraction technology and three-dimensional (3D) composites made using decellularized porcine cartilage graft (dPCG) as scaffolds, platelet-rich plasma (PRP), thrombin as signals and chondrocytes as cells for the treatment of articular cartilage defects. In this study, in vitro and in vivo cartilage regeneration and the expression of chondrogenic markers were examined. Decellularized cartilage graft (dPCG) was evaluated for the extent of cell and DNA removal. Residual cartilage ECM structure was confirmed to be type II collagen by SDS PAGE and immunostaining. The new 3D composite with dPCG (100 mg and 2 × 10⁶ chondrocytes) scaffold promotes chondrogenic marker expression in vitro. We found that the in vivo 3D composite implanted cartilage defect showed significant regeneration relative to the blank and control implant. Immunohistochemical staining showed increase of expression including Collagen type II and aggrecan in 3D composite both in vitro and in vivo studies. In this study, the bioengineered 3D composite by combining dPCG scaffold, chondrocytes, and PRP facilitated the chondrogenic marker expression in both in vitro and in vivo models with accelerated cartilage regeneration. This might serve the purpose of clinical treatment of large focal articular cartilage defects in humans in the near future.

Hyaluronic acid and platelet-rich plasma for the management of knee osteoarthritis

PURPOSE

Symptomatic knee osteoarthritis (OA) remains a substantial cause of pain and disability worldwide and effective management in young patients without indications for total knee arthroplasty remains challenging. Intra-articular injections represent a viable option in the non-operative treatment of knee OA. Hyaluronic acid (HA) and platelet-rich plasma (PRP) are two commonly utilized intra-articular treatment modalities that are of particular clinical interest in the current literature. The purpose of this manuscript is to provide a concise review of the current literature on the use of HA, PRP, and HA-PRP conjugates for the treatment of symptomatic knee OA.

METHODS

A review of the literature utilizing PubMed, OVID/Medline, and Cochrane databases on basic science and clinical literature pertaining to preparation, composition, and outcomes of HA, PRP, and HA-PRP conjugates in patients with symptomatic knee OA.

RESULTS

Both HA and PRP have been shown to be efficacious for the treatment of symptomatic knee OA, with HA injections providing limited short-term improvement, while PRP may provide greater therapeutic relief, particularly with the use of leukocyte-poor (LP-PRP) formulations. Despite limited data, the combination of different formulations of HA-PRP conjugates may provide a synergistic effect, resulting in a clinically significant improvement in both pain and function.

CONCLUSION

In patients with symptomatic knee OA, intra-articular HA and PRP provide short-term improvement in pain and function, while the efficacy of HA-PRP conjugates warrants further study.

Platelet-rich plasma versus hyaluronic acid in the treatment of knee osteoarthritis: a meta-analysis

Background

This study aimed to evaluate the clinical efficacy of platelet-rich plasma (PRP) injection compared with hyaluronic acid (HA) injection for patients undergoing knee osteoarthritis.

Methods

We systematically searched electronic databases including PubMed, Embase, Web of Science, and the Cochrane Library on January 23, 2020 to identify relevant studies issued in English languages. The outcomes evaluating the efficacy of knee osteoarthritis (KOA) treatment were Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores (WOMAC pain, function, stiffness, and total scores) at 1, 3, 6, and 12 months; International Knee Documentation Committee (IKDC) scores, Lequesne Index score, Visual Analog Scale (VAS) scores, EQ-VAS scores, and KOOS scores. The pooled data were analyzed by Stata 12.0.

Results

A total of 20 RCTs were enrolled in the present meta-analysis. The pooled results demonstrated that platelet-rich plasma (PRP) injection reduced pain more effectively than hyaluronic acid (HA) injection at 6-month and 12-month follow-up evaluated by WOMAC pain scores and VAS scores. EQ-VAS in the patients treated with PRP injection was lower than that in patients with HA injection at 12 months. Moreover, the patients with PRP injection had a better function recovery than those with HA injection at 1-month, 3-month, 6-month, and 12-month follow-up, as evaluated by WOMAC function scores. WOMAC total scores showed significant difference at 6-month and 12-month follow-up. The IKDC scores indicated PRP injection was significantly more effective than HA injection at 3 months and 6 months. However, the Lequesne Index scores, KOOS scores, and adverse events did not show any significant difference between groups.

Conclusion

Intra-articular PRP injection appeared to be more efficacious than HA injection for the treatment of KOA in terms of short-term functional recovery. Moreover, PRP injection was superior to HA injection in terms of long-term pain relief and function improvement. In addition, PRP injection did not increase the risk of adverse events compared to HA injection.

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).

Biological perspectives and current biofabrication strategies in osteochondral tissue engineering

Articular cartilage and the underlying subchondral bone are crucial in human movement and when damaged through disease or trauma impacts severely on quality of life. Cartilage has a limited regenerative capacity due to its avascular composition and current therapeutic interventions have limited efficacy. With a rapidly ageing population globally, the numbers of patients requiring therapy for osteochondral disorders is rising, leading to increasing pressures on healthcare systems. Research into novel therapies using tissue engineering has become a priority. However, rational design of biomimetic and clinically effective tissue constructs requires basic understanding of osteochondral biological composition, structure, and mechanical properties. Furthermore, consideration of material design, scaffold architecture, and biofabrication strategies, is needed to assist in the development of tissue engineering therapies enabling successful translation into the clinical arena. This review provides a starting point for any researcher investigating tissue engineering for osteochondral applications. An overview of biological properties of osteochondral tissue, current clinical practices, the role of tissue engineering and biofabrication, and key challenges associated with new treatments is provided. Developing precisely engineered tissue constructs with mechanical and phenotypic stability is the goal. Future work should focus on multi-stimulatory environments, long-term studies to determine phenotypic alterations and tissue formation, and the development of novel bioreactor systems that can more accurately resemble the in vivo environment.

The Role of Biologic Agents in the Non-operative Management of Elbow Ulnar Collateral Ligament Injuries

PURPOSE OF REVIEW

Injuries to the elbow ulnar collateral ligament (UCL) are especially common in the overhead throwing athlete. Despite preventative measures, these injuries are occurring at increasing rates in athletes of all levels. UCL reconstruction techniques generally require a prolonged recovery period and introduce the potential for intraoperative complications prompting investigations into more conservative treatment measures based on specific patient and injury characteristics. The purpose of this review is to describe the current literature regarding the use of biologic augmentation in the management of UCL injuries. Specifically, this review will focus on the basic science background and clinical investigations pertaining to biologic augmentation utilizing platelet-rich plasma (PRP) and autologous stem cells.

RECENT FINDINGS

Despite some evidence supporting the use of PRP therapy in patients with partial UCL tears, there is no current consensus regarding its true efficacy. Similarly, due to a lack of clinical investigations, no consensus exists regarding the utilization of autologous stem cell treatments in the management of UCL injuries. Management of UCL injuries ranges from non-operative treatment with focused physical therapy protocols to operative reconstruction. The use of biologic augmentation in these injuries continues to be investigated in the orthopedic community. Currently, no consensus exists regarding the efficacy of either PRP or autologous stem cells and further research is needed to further define the appropriate role of these treatments in the management of UCL injuries.

Optimization of a rapid one-step platelet-rich plasma preparation method using syringe centrifugation with and without carprofen

Background

Carprofen and platelet-rich plasma (PRP) are widely used in small animal clinical practice. Separation layers have been used during blood centrifugation to increase platelet yield. The objectives of this study were to (1) identify the optimal centrifugation force for the one-step PRP preparation, (2) determine whether there is an advantage to using carprofen in one-step PRP preparation, and (3) compare platelet morphology from one-step PRP preparation with and without carprofen. We hypothesized that injectable carprofen (emulsion formula) could be used successfully as the separation layer in PRP preparation.

Results

Samples from 14 healthy dogs were used to determine the optimal centrifugation force using one-step PRP preparation in a disposable syringe without carprofen, with forces set at 300, 500, 700, 900, 1100, 1300, and 1500 xg for 5 min. Optimum centrifugation force, plasma volume, and platelet concentrations of one-step PRP preparation were found and recovered at 900 xg, 1.9 ± 0.28 ml, and 260.50 ± 58.39 X 10³ cell/μl, respectively. Samples from 12 healthy dogs were used to determine the optimal force (with forces set at 300, 500, 700, and 900 xg) for 5 min using one-step PRP preparation with carprofen. Optimum centrifugation force, plasma volume, and platelet concentrations for one-step PRP preparation with carprofen were found and recovered at 500 xg, 0.62 ± 0.16 ml and 948.50 ± 261.40 X 10³ cell/μl, respectively. One-step PRP preparation with carprofen increased the platelet yield from baseline by 1.76 and 4.95 fold, respectively. Samples from 3 healthy dogs were used to observe platelet morphologies after centrifugation by scanning electron microscopy. Images of platelets on glass slides from both preparation methods revealed pseudopods emerging from the margins of the discoid platelets.

Conclusions

One-step PRP centrifugation both with and without carprofen increased the platelet yield, but using carprofen (emulsion formula) as a separation layer resulted in a higher platelet yield. The clinical usefulness of PRP products from these methods should be further investigated.

Platelet-Rich Plasma Enhances Distal Flap Viability and Underlying Vascularity in a Radiated Rotational Flap Rodent Model

Importance: Autologous platelet-rich plasma (PRP) has received widespread attention due to its physiologic healing properties, augmenting the body's natural healing process through platelet activation and release of growth factors. The effects of PRP on radiated tissue have been inadequately studied in vivo. Objective: To determine whether PRP can be used to improve viability of radiated tissue subjected to a clinically meaningful stressor, in this case a rotational skin flap. Design, Setting, Participants: This is a prospective trial using a radiated rat abdominal rotational flap model in the laboratory. Male Sprague-Daley rats were used in this study. Harvested PRP or saline control was injected into rotational flaps immediately after surgery. Progression of necrosis was documented with photo analysis. After 1 week, animals were sacrificed and flap tissue was stained and analyzed for presence of vascular tissue. Intervention: PRP versus control injection into radiated skin tissue. Main Outcomes and Measures: Percentage necrosis of rotational flap and number of vascular channels stained with CD31 present in flap tissue. Results: PRP administration helped rescue the distal flap from necrosis, achieving viability similar to nonradiated controls. Superficial vascularity was similarly increased fivefold in radiated tissue if PRP was given postoperatively, mirroring the vascular density of nonradiated tissue. Conclusions and Relevance: PRP may enhance distal rotational flap viability after radiation, possibly by protecting superficial vessels from tissue necrosis when administered at the time of surgery.

Assessment of a Single Intra-Articular Stifle Injection of Pure Platelet Rich Plasma on Symmetry Indices in Dogs with Unilateral or Bilateral Stifle Osteoarthritis from Long-Term Medically Managed Cranial Cruciate Ligament Disease

Purpose

The use of platelet-rich plasma (PRP) to treat canine osteoarthritis has gained support within the scientific community. PRP effects on pain control for degenerative joint disease induced by naturally occurring cranial cruciate ligament instability are limited, particularly in a cohort of dogs with chronic instability and osteoarthritis (>12 months), representing a commonly encountered clinical population that often defaults to medical management. The goal of this study was to assess the effects of a single intra-articular PRP injection into an effected stifle in this cohort, to assess response to treatment, quantitative kinetic data as it relates to percent body weight for peak vertical force (PVF) and vertical impulse (VI) were collected, and symmetry indices related to PVF were determined.

Methods

Twelve dogs with unilateral or bilateral osteoarthritis with ruptured, non-stabilized cranial cruciate ligaments over 12 months duration were identified. Unilateral injections of 2.5 mL of a PRP preparation into the most severely affected stifle based on kinetic analysis was performed. Repeat pressure-sensitive walkway analysis was conducted monthly for 3 months. Peak vertical force (PVF) and vertical impulse (VI) were normalized to body weight and identified in all four limbs. Previously published symmetry indices regarding PVF were calculated, comparing the treated limb with the contralateral limb, ipsilateral forelimb, and contralateral forelimb.

Results

After treatment, hind limb symmetry index (SI) regarding PVF showed improved symmetry, suggesting more weight placement at all-time points after injection of the most affected limb (p < 0.01). Further, PVF asymmetry indices assessing contralateral fore (CFL) and hind limb (CHL) as well as ipsilateral forelimb (IFL) revealing a significant decrease from baseline for CHL at week 4 (p = 0.02), but not weeks 8 and 12. The CFL showed decreased differences in symmetry from baseline at each time point (p = 0.03). There were no statistically significant changes in PVF or VI over time in treated dogs.

Conclusion

A single injection of PRP improved kinetics for minimally 4 weeks with some data suggesting an effect for up to 12 weeks. Therefore, PRP might be a viable therapeutic option for instability and inflammation associated with chronic osteoarthritis due to cranial cruciate ligament disease in the non-surgical patient.

Procedural Treatments for Knee Osteoarthritis: A Review of Current Injectable Therapies

Knee osteoarthritis is a common painful degenerative condition affecting the aging Canadian population. In addition to pain and disability, osteoarthritis is associated with depression, comorbid conditions such as diabetes, and increased caregiver burden. It is predicted to cost the Canadian healthcare system $7.6 billion dollars by 2031. Despite its high cost and prevalence, controversy persists in the medical community regarding optimal therapies to treat knee osteoarthritis. A variety of medications like nonsteroidal anti-inflammatories and opioids can cause severe side effects with limited benefits. Total knee arthroplasty, although a definitive management, comes with risk such as postoperative infections, revisions, and chronic pain. Newer injectable therapies are gaining attention as alternatives to medications because of a safer side effect profile and are much less invasive than a joint replacement. Platelet-rich plasma is beginning to replace the more common injectable therapies of intra-articular corticosteroids and hyaluronic acid, but larger trials are needed to confirm this effect. Small studies have examined prolotherapy and stem cell therapy and demonstrate some benefits. Trials involving genicular nerve block procedures have been successful. As treatments evolve, injectable therapies may offer a safe and effective pathway for patients suffering from knee osteoarthritis.

An Analysis of Current Treatment Trends in Platelet-Rich Plasma Therapy in the Medicare Database

Background:

The use of platelet-rich plasma (PRP) in the Medicare population is not well described.

Purpose:

To investigate the national use of PRP among Medicare beneficiaries, including the incidence and conditions for which it was used in both operative and nonoperative settings, and determine charges to Medicare.

Study Design:

Descriptive epidemiology study.

Methods:

The Medicare Standard Analytical Files within the PearlDiver database were queried for PRP injections by use of Current Procedural Terminology (CPT) code 0232T from 2010 to 2014. A search of every associated International Classification of Diseases, 9th Revision, code and CPT code on the day of the injection was performed, and codes were broadly categorized as shoulder, knee, elbow, hip, and foot/ankle. These categories were then subdivided into 2 groups based on whether the injection was performed at the time of surgery or for a nonoperative condition. The patient data were analyzed by demographics and geographic region. In further analysis, the charges sent to Medicare for PRP injections were stratified by year and musculoskeletal site.

Results:

A total of 3654 PRP injections were coded for and administered during the study period; 57% of recipients were men and 33% were 65 to 69 years of age. We found that 42% of all PRP injections were administered in the southern geographic region. PRP injections were most commonly associated with shoulder diagnoses, followed closely by the foot and ankle and by the knee. The majority of injections given for shoulder conditions were performed at the time of surgery, whereas the majority of knee conditions treated with PRP were associated with nonoperative treatments. Annual charges to Medicare for PRP injections increased 400%, from $500,000 in 2010 to more than $2 million in 2014.

Conclusion:

The use and breadth of PRP therapy have increased substantially in Medicare beneficiaries. Further research is required to obtain a consensus on treatment recommendations for PRP use in this population in addition to strategies to obtain insurance reimbursement.

Achyranthes bidentata extract protects chondrocytes functions through suppressing glycolysis and apoptosis via MAPK/AKT signaling axis

Osteoarthritis (OA) is considered to be a joint-associated disorder and one of leading reasons for disability, however, potential mechanism has never been clarified. The purpose of this research was to evaluate protective-effects of Achyranthes Bidentata extracts (ABE) on chondrocytes function in osteoarthritis. We performed a systematic investigation of transcriptional and proteomic landscapes to identify the underlying mechanisms behind effects of ABE on chondrocytic functions. OA animal models were generated in the present research. Chondrocytes were isolated and cultured, and then prepared for GeneChip analysis. Two-dimensional gel electrophoresis and LC-MS/MS analysis were conducted to analyze samples. Quantitative real-time PCR (qRT-PCR) and western blotting were used to evaluate expression of protein kinase B (AKT), β-tubulin and β-action. Apoptosis and glycolysis pathway were significantly compromised in chondrocytes with ABE stimulation as revealed by both transcriptional and proteomic data. Consistently, ABE suppressed chondrocytes apoptosis and glycolytic activity in vitro through modulating multiple genes, such as Plk2, Casp1/12 and Cers1 as well as Pkm2, Eno1/3 and Pgk2. Mechanically, ABE activated MAPK signaling pathway and suppressed AKT signaling pathway, therefore, reducing the glycolysis to provide survival benefits. We extended our analysis by verifying insulin-like growth factor 1 (IGF-1) and MAP kinase 1 (MEK1) in chondrocytes function. Depletion of either IGF-1 or MEK1 impaired AKT expression and phosphorylation, leading to the enhanced chondrocyte apoptosis and reduced cell proliferation. In conclusion, our study provided systematic view and molecular basis for ABE to serve as potential intervention of OA via suppressing AKT signaling.

Clinical outcomes following injections of leukocyte-rich platelet-rich plasma in osteoarthritis patients

Background

Scientists are trying to discover how to repair cartilage defects in knee osteoarthritis (KOA). In our previous study, we found a fibrocartilage-rich cover over the defective portions of cartilage after administering leukocyte-rich platelet-rich plasma (LR-PRP). This study aimed to investigate the efficacy of multiple injections of LR-PRP for the treatment of KOA and determine an LR-PRP treatment protocol for KOA in actual clinical practice.

Hypothesis

We hypothesized that using abundant LR-PRP would improve outcomes in patients with KOA.

Study design

Prospective, cross-sectional, interventional, randomized trial.

Methods

Intra-articular LR-PRP injections were administered to 50 knees. Patients received six injections of LR-PRP in total, which were administered at 4-week intervals. Patients were evaluated based on clinical outcomes, including visual analog scale (VAS) scores, Knee injury and Osteoarthritis Outcome Scores (KOOS), and magnetic resonance images (MRI) and radiographic findings before treatment and at 3 and 6 months after treatment. We investigated the recurrence of pain and presence/absence of MRI changes. Furthermore, we examined the Outcome Measures In Rheumatology-Osteoarthritis Research Society International (OMERACT-OARSI) responder criteria.

Results

The mean improvement rate, as assessed by VAS, was 61.6% (P < .0001). Concerning OMERACT-OARSI, 37 of 50 knees (74%) were considered responders. There was a significant difference in the follow-up MRI findings, as assessed by the MRI Osteoarthritis Knee Score for bone marrow lesions (P < .007). No significant difference in osteoarthritis grade was observed.

Conclusion

Our LR-PRP procedure resulted in 74% of knees being classified as responders, regardless of the degree of knee deformation. Multiple injections of LR-PRP was effective for advanced grades of KOA. Thus, based on the results of our study, we believe that LR-PRP should be implemented as an additional conservative treatment option for non-operative management of OA.

Trial registration

Japan Medical Association Center for Clinical Trials (JMA-XXX).

The Clinical Use of Biologics in the Knee Lesions: Does the Patient Benefit?

PURPOSE OF REVIEW

Overview the outcomes of the latest use of platelet-rich plasma (PRP) for the treatment of knee lesions in the clinics and discuss the challenges and limitations.

RECENT FINDINGS

Recent clinical studies mainly indicate there may be benefit of PRP usage for the treatment of knee lesions. As an autologous source of bioactive components, PRP has been shown to be typically safe, free of major adverse outcomes. The use of PRP has been continuously increasing, and some well-designed, double-blinded, placebo-controlled clinical trials have been published. Clinical outcomes relating to PRP usage are multifactorial and depend on the severity of the lesion and patient characteristics. Although PRP is safe to use and it can be easily applied in the clinics, case-specific considerations are needed to determine whether PRP could be beneficial or not. If the use of PRP is favored, then, the configuration/optimization of the preparation and administration/delivery strategy with or without a concomitant treatment may further enhance the clinical outcomes and patients' experience.

Cellular Components and Growth Factor Content of Platelet-Rich Plasma With a Customizable Commercial System

BACKGROUND

Platelet-rich plasma (PRP) is an autologous orthobiologic treatment option for musculoskeletal conditions with favorable results in a limited number of high-quality clinical trials. Because different blood-processing methods result in PRP with varying cellular and growth factor content, it is critical that clinicians understand the content of the specific PRP being used in clinical practice. One adjustable system, the Angel System, has few independent laboratory reports on the specific composition of its PRP. The goal of this study was to quantify the cellular and growth factor composition of PRP produced by this system at its lowest hematocrit settings.

HYPOTHESIS

The authors hypothesized that the system would significantly concentrate platelets over baseline and, at the lowest hematocrit settings, would reduce leukocytes to produce leukocyte-poor PRP.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Ten healthy male volunteers donated 150 mL of whole blood for processing. Three separate processing cycles were performed for each sample at the 0%, 1%, and 2% hematocrit settings. The resultant PRP from each cycle was sent for complete blood counts and enzyme-linked immunosorbent assay to quantify the following growth factors: platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF), insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor (VEGF).

RESULTS

The system consistently concentrated platelets 5-fold over baseline, with no significant differences among settings. Leukocytes were concentrated at all settings, between 2 and 5 times over baseline. The 0% and 1% settings had significantly lower leukocyte concentrations than the 2% setting. Lymphocytes made up >89% of the leukocyte differential, while neutrophils represented <11% of the differential at each setting. There was a significant increase in PDGF and bFGF, a significant decrease in IGF-1, and no change in VEGF, with no difference among settings.

CONCLUSION

The system consistently concentrated platelets 5 times but was unable to reduce leukocytes, therefore resulting in leukocyte-rich PRP at each setting tested. Leukocytes had a differential composition of >89% lymphocytes and <11% neutrophils. For all settings, PDGF and bFGF were concentrated; IGF-1 was reduced; and VEGF was not significantly different from baseline.

CLINICAL RELEVANCE

These data can serve to guide clinicians considering using this particular PRP system. It consistently yielded leukocyte-rich PRP with a lymphocyte-predominant/neutrophil-reduced profile. Further research is needed to better understand how to apply this specific PRP in clinical practice.

Active viscosupplements for osteoarthritis treatment

OBJECTIVE

Osteoarthritis is a chronic, painful and disabling disease which prevalence is increasing in developing countries. Patients with osteoarthritis present a reduced synovial fluid viscoelasticity due to a reduction in concentration and molecular weight of hyaluronic acid. Currently, the main treatment used to restore the compromised rheological properties of synovial fluid is the viscosupplementation by hyaluronic acid injections that can be combined with oral anti-inflammatory drugs for pain relief. Combination of viscosupplements with chemical agents or drugs is emerging as a new strategy to provide a double action of synovial fluid viscoelasticity recovery and the therapeutic effect of the bioactive principle.

METHODS

In this review, we present the latest research on the combination of viscosupplements with active molecules. We conducted a literature review of articles published in different web search engines and categorized according to the active molecule introduced into the viscosupplement.

RESULTS

Generally, the introduction of anti-inflammatory molecules have shown to improve pain relief although some cytotoxicity has been demonstrated especially for non-steroidal anti-inflammatory drugs. Other molecules such as antioxidant or disease modifying osteoarthritis drugs have been reported to improve viscosupplementation action. Drug delivery systems combined with hyaluronic acid could enhance the activity of the encapsulated molecules and provide better control over the drug release. Finally, biological approaches such as the use of stem cells or platelet-rich plasma seem to be the most promising strategies for cartilage recovery.

CONCLUSIONS

Combination therapy of viscosupplements with therapeutic agents, drug delivery systems or regenerative therapies can improve viscosupplementation outcome in terms of pain relief and joint functionality. However, further research is needed in order to reach more conclusive results.