The impact of osteoarthritis in the United States: a population-health perspective: A population-based review of the fourth most common cause of hospitalization in U.S. adults

Genetic Predictors of Knee Pain in Persons With Mild to Moderate Osteoarthritis

The purpose of this study was to examine genetic variability and knee pain in persons with osteoarthritis (OA). Seventy-five participants with medial compartment knee OA were recruited from a large Midwestern tertiary care center. Participants exhibited a mean age of 56.3 years; females comprised 61% of the sample. Measures of pain included subjective pain intensity at rest and with movement, cutaneous mechanical sensation and pain testing, heat pain threshold, and pressure pain threshold. Seventy-four participants were genotyped for 25 genetic variants across 15 candidate genes for central or peripheral pain pathways. Analysis suggests a role for four genes (EDNRA, COMT, BDRKB1, and IL1B) in several components of pain in persons with knee OA. The results from this study will help guide the development and evaluation of tailored strategies to decrease pain, improve function, and prevent the development of new chronic pain syndromes in older adults experiencing OA. [Research in Gerontological Nursing, xx(x), xx-xx.].

Pathological calcification in osteoarthritis: an outcome or a disease initiator?

In the progression of osteoarthritis, pathological calcification in the affected joint is an important feature. The role of these crystallites in the pathogenesis and progression of osteoarthritis is controversial; it remains unclear whether they act as a disease initiator or are present as a result of joint damage. Recent studies reported that the molecular mechanisms regulating physiological calcification of skeletal tissues are similar to those regulating pathological or ectopic calcification of soft tissues. Pathological calcification takes place when the equilibrium is disrupted. Calcium phosphate crystallites are identified in most affected joints and the presence of these crystallites is closely correlated with the extent of joint destruction. These observations suggest that pathological calcification is most likely to be a disease initiator instead of an outcome of osteoarthritis progression. Inhibiting pathological crystallite deposition within joint tissues therefore represents a potential therapeutic target in the management of osteoarthritis.

Osteoarthritis and inflammation: a serious disease with overlapping phenotypic patterns

Globally, osteoarthritis (OA) is the most prevalent arthritic condition in those aged over 60 years. OA has a high impact on patient disability and is associated with a significant economic burden. Pain is the most common first sign of disease and the leading cause of disability. Data demonstrating the increasing global prevalence of OA, together with a greater understanding of the burden of the disease, have led to a reassessment of the seriousness of OA and calls for the designation of OA as a serious disease in line with the diseases impact on comorbidity, disability, and mortality. While OA was traditionally seen as a prototypical 'wear and tear' disease, it is now more accurately thought of as a disease of the whole joint involving cartilage together with subchondral bone and synovium. As more has become known of the pathophysiology of OA, it has become increasingly common for it to be described using a number of overlapping phenotypes. Patients with OA will likely experience multiple phenotypes during their disease. This review focuses on what we feel are three key phenotypes: post-trauma, metabolic, and aging. A greater understanding of OA phenotypes, particularly at the early stages of disease, may be necessary to improve treatment outcomes. In the future, non-pharmacological and pharmacological treatments could be tailored to patients based on the key features of their phenotype and disease pathway.

Spontaneous dog osteoarthritis - a One Medicine vision

Osteoarthritis (OA) is a global disease that, despite extensive research, has limited treatment options. Pet dogs share both an environment and lifestyle attributes with their owners, and a growing awareness is developing in the public and among researchers that One Medicine, the mutual co-study of animals and humans, could be beneficial for both humans and dogs. To that end, this Review highlights research opportunities afforded by studying dogs with spontaneous OA, with a view to sharing this active area of veterinary research with new audiences. Similarities and differences between dog and human OA are examined, and the proposition is made that suitably aligned studies of spontaneous OA in dogs and humans, in particular hip and knee OA, could highlight new avenues of discovery. Developing cross-species collaborations will provide a wealth of research material and knowledge that is relevant to human OA and that cannot currently be obtained from rodent models or experimentally induced dog models of OA. Ultimately, this Review aims to raise awareness of spontaneous dog OA and to stimulate discussion regarding its exploration under the One Medicine initiative to improve the health and well-being of both species.

Osteoarthritis occurs spontaneously in pet dogs, which often share environmental and lifestyle risk-factors with their owners. This Review aims to stimulate cooperation between medical and veterinary research under the One Medicine initiative to improve the welfare of dogs and humans.

Dogs have many analogous spontaneous diseases that result in end-stage osteoarthritis (OA).

Inbreeding and the predisposition of certain dog breeds for OA enable easier identification of candidate genetic associations than in outbred humans.

Dog OA subtypes offer a potential stratification rationale for aetiological differences and alignment to analogous human OA phenotypes.

The relatively compressed time course of spontaneous dog OA offers longitudinal research opportunities.

Collaboration with veterinary researchers can provide tissue samples from early-stage OA and opportunities to evaluate new therapeutics in a spontaneous disease model.

Awareness of the limitations and benefits of using clinical veterinary patients in research is important.

The immediate effects of knee flexion range of motion following manual therapy or self-stretching/active range of motion following a total knee arthroplasty: a case report

[Purpose] The purposes of this case study are to: (1) report the immediate effects of knee flexion range of motion following manual therapy (MT) and self-stretching/AROM following a total knee arthroplasty (TKA). (2) contribute empirical evidence to the literature through reports within this case study. [Participant and Methods] For 6 days, the authors utilized a different MT technique and 1 day of self-stretching and active range of motion for an 85-year-old male who was 3 days status post right TKA. [Results] The greatest gains for AROM/PROM for knee flexion were achieved while performing typical arthrokinematic motion joint mobilizations, for AROM and PROM, resulting in a gain of 10 degrees and 10 degrees, respectfully. [Conclusion] We theorize that performing typical arthrokinematic motion joint mobilizations stimulates a greater response from the mechanoreceptors and therefore a greater stimulation response to the central and peripheral nervous systems. This greater stimulation may explain the greatest immediate gain in knee flexion range of motion being performed by typical arthrokinematic motion joint mobilizations. The outcomes of this study demonstrate the start of some empirical evidence while exploring the immediate effects of knee flexion range of motion following manual therapy and self-stretching/AROM following a TKA.

Recommendation Rates for Physical Therapy, Lifestyle Counseling, and Pain Medications for Managing Knee Osteoarthritis in Ambulatory Care Settings: A Cross-Sectional Analysis of the National Ambulatory Care Survey (2007-2015)

OBJECTIVE

To describe and compare triennial rates of physicians' recommendations for physical therapy (PT), lifestyle counseling, and pain medication for knee osteoarthritis (OA) and to identify patient, physician, and practice factors associated with each treatment recommendation.

METHODS

We conducted a cross-sectional analysis examining data between 2007 and 2015 from the National Ambulatory Medical Care Survey. Visits to orthopedists and primary care physicians for knee OA were identified and assessed for the following: PT referral, lifestyle counseling, nonsteroidal antiinflammatory drug (NSAID) prescriptions, and narcotics prescriptions. Triennial rates for each treatment were calculated. We examined associations between patient (e.g., race, insurance), physician, and practice factors (e.g., ownership, location) and treatments prescribed using multivariate logistic regression that accounted for complex sampling design.

RESULTS

A total of 2,297 physician visits related to knee OA (~67 [±4] million weighted visits) were identified. For visits to orthopedists, PT and lifestyle recommendation rates declined (158 to 88 of 1,000 visits and 184 to 86 of 1,000 visits, respectively), while NSAID and narcotics prescriptions increased (132 to 278 of 1,000 visits and 77 to 236 of 1,000 visits, respectively) over time (P < 0.05). For visits to primary care physicians, there were no significant changes in rates of PT, lifestyle counseling, and narcotics prescriptions over time, while NSAIDs prescriptions increased (221 to 498 of 1,000 visits; P < 0.05). Treatment recommendations were associated with nonclinical factors, including practice type, location, and type of provider.

CONCLUSION

In patients with knee OA, PT and lifestyle counseling seem underutilized, while pain medication prescriptions increased during the investigated timeframe. Variation in treatment choices were associated with nonclinical factors. Future research is necessary to examine ways to improve PT and lifestyle utilization and reduce variation in care for knee OA.

Optimism and Psychological Resilience are Beneficially Associated With Measures of Clinical and Experimental Pain in Adults With or at Risk for Knee Osteoarthritis

OBJECTIVES

This cross-sectional study examined the associations among optimism, psychological resilience, endogenous pain inhibition, and clinical knee pain severity. Two hypotheses were tested. First, we hypothesized that experimentally tested endogenous pain inhibition would mediate the relationship between optimism and clinical knee pain severity. Second, it was also hypothesized that optimism would moderate the relationships of psychological resilience with endogenous pain inhibition and clinical knee pain severity, particularly for individuals with high optimism.

METHODS

A total of 150 individuals with or at risk for symptomatic knee osteoarthritis completed the Life Orientation Test-Revised, the Brief Resilience Scale, and the revised Short-Form McGill Pain Questionnaire-2 to assess optimism, psychological resilience, and clinical knee pain severity, respectively. Endogenous pain inhibition was examined experimentally using a conditioned pain modulation (CPM) protocol with algometry (test stimulus) and a cold pressor task (conditioning stimulus).

RESULTS

As hypothesized, results showed that increased CPM significantly mediated the association between higher optimism and lower clinical knee pain severity. Further, optimism moderated the association between psychological resilience and CPM. However, contrary to our hypothesis, greater psychological resilience was associated with enhanced CPM in individuals with low optimism only.

DISCUSSION

This study suggests that an optimistic outlook may beneficially impact clinical pain severity by altering endogenous pain modulatory capacity. Furthermore, individuals with low optimism (ie, pessimists) may be more adept at engaging resources that promote psychological resilience, which in turn, enhances endogenous pain modulatory capacity. Therefore, this study supports consideration of psychological resilience factors when evaluating experimental and clinical pain outcomes.

Biodegradable zinc oxide composite scaffolds promote osteochondral differentiation of mesenchymal stem cells

Osteoarthritis (OA) involves the degeneration of articular cartilage and subchondral bone. The capacity of articular cartilage to repair and regenerate is limited. A biodegradable, fibrous scaffold containing zinc oxide (ZnO) was fabricated and evaluated for osteochondral tissue engineering applications. ZnO has shown promise for a variety of biomedical applications but has had limited use in tissue engineering. Composite scaffolds consisted of ZnO nanoparticles embedded in slow degrading, polycaprolactone to allow for dissolution of zinc ions over time. Zinc has well-known insulin-mimetic properties and can be beneficial for cartilage and bone regeneration. Fibrous ZnO composite scaffolds, having varying concentrations of 1-10 wt.% ZnO, were fabricated using the electrospinning technique and evaluated for human mesenchymal stem cell (MSC) differentiation along chondrocyte and osteoblast lineages. Slow release of the zinc was observed for all ZnO composite scaffolds. MSC chondrogenic differentiation was promoted on low percentage ZnO composite scaffolds as indicated by the highest collagen type II production and expression of cartilage-specific genes, while osteogenic differentiation was promoted on high percentage ZnO composite scaffolds as indicated by the highest alkaline phosphatase activity, collagen production, and expression of bone-specific genes. This study demonstrates the feasibility of ZnO-containing composites as a potential scaffold for osteochondral tissue engineering.

Regenerative Medicine: "Are We There Yet?"

Translation of regenerative therapies to the patient-bench-to-bedside-is one of the global multidisciplinary challenges of our time. New cell-based therapies are reaching the clinic through staged trials leading eventually to routine adoption. The roots of stem cell therapy lie in surgical practice and transplantation medicine with multiple multidisciplinary challenges emerging to support the new therapies. Control of stem cell behavior in line with regulatory confidence is an example of these challenges. One successful journey from bench-to-bedside is the generation of cartilage through autologous cell-based approaches for use in the repair of the knee joint. An analysis of this journey in Europe reveals success and failure; new initiatives include adopting more quantitative modelling and "organ on a chip" approaches to be used in clinical translation reducing experimental time and redressing the lack of preclinical models. The current state and challenges for the field are outlined with the question posed, "are we there yet?"

Cartilage-on-cartilage cyclic loading induces mechanical and structural damage

Cartilage breaks down during mechanically-mediated osteoarthritis (OA). While previous research has begun to elucidate mechanical, structural and cellular damage in response to cyclic loading, gaps remain in our understanding of the link between cyclic cartilage loading and OA-like mechanical damage. Thus, the aim of this study was to quantify irreversible cartilage damage in response to cyclic loading. A novel in vitro model of damage through cartilage-on-cartilage cyclic loading was established. Cartilage was loaded at 1 Hz to two different doses (10,000 or 50,000 cycles) between -6.0 ± 0.2 MPa and -10.3 ± 0.2 MPa 1st Piola-Kirchhoff stress. After loading, mechanical damage (altered mechanical properties: elastic moduli and dissipated energy) and structural damage (surface damage and specimen thickness) were quantified. Linear and tangential moduli were determined by fitting the loading portion of the stress-strain curves. Dissipated energy was calculated from the area between loading and unloading stress-strain curves. Specimen thickness was measured both before and after loading. Surface damage was assessed by staining samples with India ink, then imaging the articular surface. Cyclic loading resulted in dose-dependent decreases in linear and tangential moduli, energy dissipation, thickness, and intact area. Collectively, these results show that cartilage damage can be initiated by mechanical loading alone in vitro, suggesting that cyclic loading can cause in vivo damage. This study demonstrated that with increased number of cycles, cartilage undergoes both tissue softening and structural damage. These findings are a first step towards characterizing the cartilage response to cyclic loading, which can ultimately provide important insight for delaying the initiation and slowing the progression of OA.

Single intra-articular injection of lightly cross-linked hyaluronic acid reduces knee pain in symptomatic knee osteoarthritis: a multicenter, double-blind, randomized, placebo-controlled trial

PURPOSE

The primary objective was to demonstrate the safety and effectiveness of Monovisc™ in the relief of joint pain in patients with idiopathic knee OA compared to saline injection. It was hypothesized that patient success, defined as ≥ 50% improvement from baseline and ≥ 20 mm absolute improvement from baseline in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) visual analog scale (VAS) pain score, would be greater in the Monovisc™ group compared to the Saline control group.

METHODS

In this multicenter, double-blind, randomized, placebo-controlled trial, patients with idiopathic, symptomatic, knee OA were randomized to either 4 ml single injection of Monovisc™ or 4 ml injection of 0.9% saline. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to assess patient outcomes at 2, 4, 8, 12, 20, and 26 weeks post-injection. The primary effectiveness endpoint was a 50% improvement and ≥ 20 mm improvement from baseline in the WOMAC pain through 26 weeks. Secondary outcome measures included a ≥ 20 mm improvement from baseline on the WOMAC physical function, patient global assessment, evaluator global assessment, and knee range of motion.

RESULTS

369 patients (154 male, 215 female) were randomized to either Monovisc™ or saline. The Monovisc™ group had a significantly greater rate of patient success (e.g. ≥ 50% improvement and ≥ 20 mm absolute improvement from baseline in the WOMAC pain through Week 26) compared to saline (p = 0.043).

CONCLUSIONS

Monovisc™, a single-injection intra-articular HA device, is a safe and effective treatment for providing a clinically meaningful reduction in knee pain within 2 weeks. The results of this study support the use of a single injection of hyaluronic acid (Monovisc™) for patients with symptomatic knee OA in patients older than 45 years, as a safe and effective alternative for patients who may want an alternative treatment modality or may not be candidates for partial or total knee replacement.

LEVEL OF EVIDENCE

I, multicenter, double-blind, randomized, placebo-controlled trial.

Shared Medical Appointments in Preoperative Joint Replacement: Assessing Patient and Healthcare Member Satisfaction

BACKGROUND

Shared medical appointments (SMAs) have proven to be effective in improving patient access and education while augmenting productivity. In shifting from a traditional visit model, patient and interdisciplinary healthcare team (IHCT) member satisfaction is imperative. Predominantly seen in primary care, SMA use in orthopedics is limited. After identification of access and productivity concerns, the SMA was implemented as a quality improvement project in a rural clinic. The lower extremity joint replacement (LEJR) population was chosen because of multiple preoperative appointments and costs on the healthcare system.

PURPOSE

To assess patients' and IHCT members' satisfaction levels in using an SMA for the preparation of LEJR.

RELEVANCE TO HEALTHCARE QUALITY

The SMA is an effective model offering an efficient, cost-effective methodology aligning with the Institute for Healthcare Improvement's Triple Aim.

RESULTS

Twenty SMAs were conducted. Sixty-three patients and 14 ICHT members participated. Mean (M) satisfaction rating for SMA patients (M = 4.90, SD 0.26) was significantly higher than mean for traditional patients (M = 4.03, SD 0.39). Interdisciplinary healthcare team members' attitudes toward SMAs revealed a mean score of 4.58. Incidentally, cycle times improved as did lengths of stay.

CONCLUSIONS

Lower extremity joint replacement patients and IHCT members reported high satisfaction with SMAs.

Bioactive scaffolds for osteochondral regeneration

Treatment for osteochondral defects remains a great challenge. Although several clinical strategies have been developed for management of osteochondral defects, the reconstruction of both cartilage and subchondral bone has proved to be difficult due to their different physiological structures and functions. Considering the restriction of cartilage to self-healing and the different biological properties in osteochondral tissue, new therapy strategies are essential to be developed. This review will focus on the latest developments of bioactive scaffolds, which facilitate the osteogenic and chondrogenic differentiation for the regeneration of bone and cartilage. Besides, the topic will also review the basic anatomy, strategies and challenges for osteochondral reconstruction, the selection of cells, biochemical factors and bioactive materials, as well as the design and preparation of bioactive scaffolds. Specifically, we summarize the most recent developments of single-type bioactive scaffolds for simultaneously regenerating cartilage and subchondral bone. Moreover, the future outlook of bioactive scaffolds in osteochondral tissue engineering will be discussed. This review offers a comprehensive summary of the most recent trend in osteochondral defect reconstruction, paving the way for the bioactive scaffolds in clinical therapy.

THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE

This review summaries the latest developments of single-type bioactive scaffolds for regeneration of osteochondral defects. We also highlight a new possible translational direction for cartilage formation by harnessing bioactive ions and propose novel paradigms for subchondral bone regeneration in application of bioceramic scaffolds.

Identification of the Biomarkers and Pathological Process of Osteoarthritis: Weighted Gene Co-expression Network Analysis

Osteoarthritis (OA) is a joint disease resulting in high rates of disability and low quality of life. The initial site of OA (bone or cartilage) is uncertain. The aim of the current study was to explore biomarkers and pathological processes in subchondral bone samples. The gene expression profile GSE51588 was downloaded from the Gene Expression Omnibus database. Fifty subchondral bone [knee lateral tibial (LT) and medial tibial (MT)] samples from 40 OA and 10 non-OA subjects were analyzed. After data preprocessing, 5439 genes were obtained for weighted gene co-expression network analysis. Highly correlated genes were divided into 19 modules. The yellow module was found to be highly correlated with OA (r = 0.71, p = 1e-08) and the brown module was most associated with the differences between the LT and MT regions (r = 0.77, p = 1e-10). Gene ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment indicated that the yellow module was enriched in a variety of components including proteinaceous extracellular matrix and collagen trimers, involved in protein digestion and absorption, axon guidance, ECM-receptor interaction, and the PI3K-Akt signaling pathway. In addition, the brown module suggests that the differences between the early (LT) and end (MT) stage of OA are associated with extracellular processes and lipid metabolism. Finally, 45 hub genes in the yellow module (COL24A1, COL5A2, COL3A1, MMP2, COL6A1, etc.) and 72 hub genes in the brown module (LIPE, LPL, LEP, SLC2A4, FABP4, ADH1B, ALDH4A1, ADIPOQ, etc.) were identified. Hub genes were validated using samples from cartilage (GSE57218). In summary, 45 hub genes and 72 hub genes in two modules are associated with OA. These hub genes could provide new biomarkers and drug targets in OA. Further studies focusing on subchondral bone are required to validate these hub genes and better understand the pathological process of OA.

Cost-of-illness of knee osteoarthritis: potential cost savings by not undergoing arthroplasty within the first 2 years

Purpose

Although knee arthroplasty (KA) is the largest source of hospitalization costs for knee osteoarthritis (OA), some studies have suggested reducing the use of “low-value” interventions, such as intra-articular hyaluronic acid (HA), to lower health care costs. However, those studies fail to consider that HA has demonstrated benefits in extending time to more costly KA or avoiding KA altogether. We evaluated 1) the overall knee OA costs (direct) within a 2-year period; 2) the relative contribution of HA and KA costs; 3) the direct cost savings from HA patients not undergoing KA.

Patients and methods

Knee OA patients were identified from the Optum Clinformatics data set, which includes physician, facility, and pharmacy claims data from privately insured patients of all ages. Patients were stratified in the no HA, non-hylan G-F 20, and hylan G-F 20 cohorts. The cumulative costs (payer perspective) were evaluated for all knee OA-related claims (adjusted to Consumer Price Index Jan 2017$) for patients who had at least 2 years follow-up. Costs were stratified into various clinical categories.

Results

The study cohort included 2,030,497 knee OA patients, of which 65,144 patients (3.2%) underwent KA. The cost of treating knee OA within the 2-year follow-up period was estimated to be $4.99 billion (B). The majority of the costs (69%) were attributed to KA patients (3.2% of patients). In all, 15.9% of the HA patients underwent KA within 2 years, but HA only contributed 1.7% to the total costs for these patients. The remaining 84.1% of HA patients did not undergo KA, which saved an estimated total of $1.54B (average $20,740 per patient) or 83.9%, after accounting for their non-KA therapies.

Conclusion

Our study estimated substantial cost savings through a large percentage of HA patients not undergoing KA. Although a fraction of patients moved on from their conservative therapy to undergo KA within the 2-year period, HA attributed to <2% of their total treatment costs.

Role of MicroRNA-141 in the Aging Musculoskeletal System: A Current Overview

MicroRNA's are small non-coding RNAs that regulate the expression of genes by targeting the 3' UTR's of mRNA. Studies reveal that miRNAs play a pivotal role in normal musculoskeletal function such as mesenchymal stem cell differentiation, survivability and apoptosis, osteogenesis, and chondrogenesis. Changes in normal miRNA expression have been linked to a number of pathological disease processes. Additionally, with aging, it is noted that there is dysregulation in the normal function of stem cell differentiation, bone formation/degradation, chondrocyte function, and muscle degeneration. Due to the change in expression of miRNA in degenerative musculoskeletal pathology, it is believed that these molecules may be at least partially responsible for cellular dysfunction. A number of miRNAs have already been identified to play a role in osteoarthritis, osteoporosis and sarcopenia. One miRNA that has become of interest recently is miRNA 141. The purpose of this article is to review the current literature available on miRNA 141 and how it could play a role in osteoporosis, osteoarthritis and musculoskeletal pathology overall.

The use of PRP injections in the management of knee osteoarthritis

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

Evaluating the use of intra-articular injections as a treatment for painful hip osteoarthritis: a randomized, double-blind, multicenter, parallel-group study comparing a single 6-mL injection of hylan G-F 20 with saline

OBJECTIVE

Hip osteoarthritis (OA) is difficult to treat. Steroid injections reduce pain with short duration. With widespread adoption of office-based, image-guided injections, hyaluronic acid is a potentially relevant therapy. In the largest clinical trial to-date, we compared safety/efficacy of a single, 6-mL image-guided injection of hylan G-F 20 to saline in painful hip OA.

METHOD

357 patients were enrolled in a multicenter, double-blind, randomized saline placebo- controlled trial. Subjects were ≥35 years of age, with painful (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]-A1:5.0-8.0; numeric rating scale [NRS]: 0-10) mild-to-moderate hip OA (Kellgren-Lawrence grade II/III) and minimal contralateral hip pain (WOMAC-A1 < 4). Outcome measures included "pain on walking" (WOMAC-A1 and -A), Patient Global Self-Assessment (PTGA), WOMAC-A1 responder rate (+≥2 points on NRS), and adverse events (AEs) over 26 weeks.

RESULTS

357 patients (hylan G-F 20 single:182; saline:175) were enrolled. Both groups demonstrated significant pain improvement from baseline over 26 weeks (P < 0.0001); saline-induced pain reduction was a remarkable 35%. WOMAC-A and PTGA scores also significantly improved (P < 0.0001). No statistically significant difference was observed between groups in WOMAC-A1 scores (hylan G-F 20 single:-2.19 ± 0.16; saline:-2.26 ± 0.17) or WOMAC-A1 responders (41-52%). Treatment-related AE rates at target hip were similar (hylan G-F 20 single:23 patients [12.8%]; saline:12 [7.0%]). Posthoc analysis found, despite protocol requirements, many patients had psychological (31%) or potential neuropathic pain (27.5%) conditions.

CONCLUSION

A single 6-mL hylan G-F 20 injection or saline for painful hip OA resulted in similar, statistically significant/clinically relevant pain and function improvements up to 6 months following injection; no differences between hylan G-F 20 and saline placebo were observed.

A randomized, controlled study to evaluate the efficacy of intra-articular, autologous adipose tissue injections for the treatment of mild-to-moderate knee osteoarthritis compared to hyaluronic acid: a study protocol

BACKGROUND

Osteoarthritis (OA) is a highly debilitating joint disease that causes progressive, irreversible damage to articular cartilage. OA takes a massive toll on society that has grown in recent decades, but no therapy has been shown to halt or reverse the progression of the disease. The critical need for better treatments and increased interest cellular therapies has spawned a new generation of "minimally manipulated" cell treatments. Autologous adipose tissue injections are among the most controversial of these new treatments. Despite a lack of clinical evidence, adipose tissue injections are often marketed as "stem cell" injections with wide-ranging regenerative benefits. The purpose of this study is to estimate the effect size of the treatment by comparing the efficacy of autologous fat to hyaluronic acid (HA). As a secondary aim, we will test for preliminary evidence of efficacy of autologous fat vs. HA.

METHODS

This is a prospective, single-center, parallel-group, randomized, controlled trial. Participants (n = 54) will receive either a single intra-articular, ultrasound-guided injection of autologous adipose tissue or a single intra-articular, ultrasound-guided injection of HA (1:1 ratio). Outcome data will be obtained at baseline, week-6 and month-6. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain domain (WOMAC-A) will be used as the primary outcome measure. Secondary clinical outcome measures include WOMAC (full), clinical anchors (pain, function, and stiffness), and the 29-point Patient-Reported Outcomes Measurement Information System (PROMIS®) profile. We will also take synovial fluid samples and assess sway velocity using a force plate, as well as analyze excess/discard adipose tissue to gain a better understanding of how intra-articular adipose tissue injections influence the biochemical environment of the joint.

DISCUSSION

Given the widespread use of intra-articular fat injections in the United States, it is critical that randomized, controlled human studies evaluating efficacy and biological activity be performed. This study is the first step in addressing this unmet need, but it is not without limitations. The most notable limitations of this study are its small size and lack of blinding, which predisposes the study to both investigator and participant bias.

TRIAL REGISTRATION

NCT03242707 // HS-17-00365 // Registration Date (First Posted): August 8, 2018.

Our experience in the application of radiofrequency neuroablation in patients with coxalgia against the background of degenerative osteoarthrosis of the hip joint

The article is concerned with the treatment of coxalgia against the background of degenerative-dystrophic diseases of the hip joint. The author carried out an analysis of foreign studies concerning with the application of radiofrequency neural ablation for the hip joint nerves. Based on the results of our own research, the author has proved that radiofrequency neuroablation of articular nervule of obturator and femoral nerves is an effective treatment of coxalgia pain syndrome against the background of degenerative osteoarthrosis

Dopamine-functionalized sulphated hyaluronic acid as a titanium implant coating enhances biofilm prevention and promotes osseointegration

A series of new hyaluronan derivatives was synthesized and tested as an antibiotic release system by antibacterial and osseointegration assays. Specifically, partially sulphated hyaluronic acid (sHA) was functionalized with dopamine (DA). The DA moiety guarantees good performance as a binding agent for coating a titanium alloy surface; furthermore, the negatively charged sHA has bone regenerative effects and a high binding affinity for positively charged antibiotics. A sHA scaffold with a defined degree of sulphation (DS =2) was selected as a good compromise between a high negative charge density and poor heparin-like anticoagulant activity, while the degree of DA derivatization (17.1%mol) was chosen based on the absence of cytotoxic activity and the promotion of osteoblast proliferation. The titanium alloy coating was investigated indirectly using a fluorescent probe and directly by environmental scanning electron microscope (ESEM) analysis. Long-duration antibiotic release was demonstrated in vitro, and antibacterial efficacy against a Staphylococcus aureus culture was shown.

Relationship between the social support and self-efficacy for function ability in patients undergoing primary hip replacement

Background

The World Health Organization (WHO) reported that nearly 25% of people will suffer from physical disability owing to the bone and joint problems until 2050. The condition of patients with this type of difficulty could be improved by increasing positive self-efficacy and instigating suitable medical treatment to implement self-efficacy for functional ability (SEFA) and physical functional ability self-care. In this study, we aim to evaluate the influence of social support on SEFA in patients after total hip arthroplasty.

Methods

This cross-sectional study used structural questionnaires, telephone appointments, and data collection to obtain patient characteristics, such as gender, age, educational level, and marital status. Questionnaires about social support and self-efficacy for functional ability (SEFA) were sent to 200 patients at 3 months following a primary total hip replacement from September 2011 to December 2014. Factor analysis was used to categorize the dimensions of social support; the t test, analysis of variance (ANOVA), and correlation analysis were applied to screen factors influencing SEFA. Multiple regression analysis was employed to ascertain the relationships between patient characteristics, social support, and SEFA.

Results

In total, 134 patients responded to the questionnaires. Lower SEFA scores were observed in patients of an older age, unmarried patients, and those with a low level of education. Correlation analysis showed that emotional information and appraisal support, instrumental support, and SEFA were positively correlated. Multiple regression analysis was applied to ascertain the relationships between patient characteristics, social support, and SEFA. We identified significant coefficient values of − 0.187 for age, 5.344 for emotional information and appraisal support, and 1.653 for instrumental support.

Conclusion

The results of this study demonstrated that in patients undergoing primary hip replacement, positive impacts on SEFA were observed in relation to emotional information, appraisal support and instrumental support. The results indicated that enhancing emotional information and appraisal support could improve a patient’s self-efficacy for functional ability.

The effectiveness of physical therapies for patients with base of thumb osteoarthritis: Systematic review and meta-analysis

BACKGROUND

Trapeziometacarpal osteoarthritis (known as base of thumb OA) is a common condition causing pain and disability worldwide.

OBJECTIVE

The purpose of this review was to evaluate the effectiveness of multimodal and unimodal physical therapies for base of thumb osteoarthritis (OA) compared with usual care, placebo or sham interventions.

DESIGN

Systematic review and meta-analysis.

METHOD

We searched MEDLINE (PubMed), CINAHL, Embase, AMED, PEDro, Cochrane Database of Systematic Review, Cochrane Register of Controlled Trials (CENTRAL) from inception to May 2017. Randomized controlled trials involving adults comparing physical therapy treatment for base of thumb OA with an inactive control (placebo or sham treatment) and reported pain, strength or functional outcomes were included. Meta-analyses were performed where possible. Methodological risk of bias was assessed with the Cochrane Risk of Bias tool.

RESULTS

Five papers with low risk of bias were included. Meta-analyses of mean differences (MD) with 95% confidence intervals (95% CI), were calculated for between-group differences in point estimates at 4 weeks post-intervention. Multimodal and unimodal physical therapies resulted in clinically worthwhile improvements in pain intensity (MD 2.9 [95% CI 2.8 to 3.0]; MD 3.1 [95% CI 2.5 to 3.8] on a 0-10 scale, respectively). Hand function improved following unimodal treatments (MD 6.8 points [95% CI 1.7 to 11.9)] on a 0-100 scale) and after a multimodal treatment (MD 20.5 (95%CI -0.7 to 41.7).

CONCLUSIONS

High quality evidence shows unimodal and multimodal physical therapy treatments can result in clinically worthwhile improvements in pain and function for patients with base of thumb OA.

Longitudinal Growth and pQCT Measures in Hutterite Children and Grandchildren Are Associated With Prevalence of Hip or Knee Replacement Resulting From Osteoarthritis in Parents and Grandparents

BACKGROUND

Osteoarthritis (OA) is one of the leading causes of disability in the world. Several genes are associated with the development of OA, and previous studies have shown adult children of individuals with OA have higher areal bone mineral density (BMD). Because childhood is an important period of growth and bone development, and body composition is known to be associated with BMD, we speculated that there may be differences in growth and bone measures among young children with a genetic predisposition to OA.

QUESTIONS/PURPOSES

(1) Do differences exist at baseline in anthropometric and peripheral quantitative CT (pQCT) measurements between children and grandchildren of individuals with OA and controls? (2) Do children and grandchildren of individuals with OA accrue bone longitudinally at a different rate than controls?

METHODS

Longitudinal anthropometric (height, weight) and bone (cortical and trabecular volumetric BMD and cross-sectional area) measurements by pQCT were obtained at baseline and 18 and 36 months on children (n = 178) and grandchildren (n = 230) of 23 individuals with hip or knee arthroplasty resulting from OA and 23 sex-matched controls (16 females each). Grandchildren (age, 8-30 years) were further categorized as growing (premenarcheal or male < 14 years, n = 99) or mature (≥ 2 years postmenarchal or males ≥ 18 years, n = 96). The remaining 35 grandchildren could not be categorized and were excluded.

RESULTS

Mature granddaughters and grandsons of individuals with OA had greater trabecular volumetric BMD than controls (236 ± 24 and 222 ± 26 mg/cm, respectively, for granddaughters, difference of 14 [95% confidence interval {CI}, 1-28] mg/cm, p = 0.041 and 270 ± 22 and 248 ± 30 mg/cm, respectively, for grandsons, difference of 22 [95% CI, 1-42] mg/cm, p = 0.040). Greater trabecular volumetric BMD was observed in daughters of individuals with OA compared with daughters of controls (228 ± 28 and 212 ± 33 mg/cm, respectively, difference of 18 [95% CI, 3-30] mg/cm, respectively [p = 0.021]). Growing granddaughters and grandsons of controls had greater decreases in cortical volumetric BMD than grandchildren of individuals with OA (time-by-group [TG] based on mixed model [± standard error] -9.7 ± 4.3 versus -0.8 ± 4.4 mg/cm/year, respectively, for granddaughters, difference of 9.0 [95% CI, 2.4-15.5] mg/cm/year, p = 0.007 and -6.8 ± 3.3 versus 4.5 ± 3.4 mg/cm/year, respectively, for grandsons, difference of 11.3 [95% CI, 4.3-18.3] mg/cm/year, p = 0.002). Cortical volumetric BMD was maintained in sons of individuals with OA, but decreased in sons of controls (-0.0 ± 1.5 versus -4.3 ± 1.0 mg/cm/year, respectively, difference of 4.3 [95% CI, 0.7-7.8] mg/cm/year, p = 0.019 [TG]). There was a greater apparent decrease in cross-sectional area among daughters of individuals with OA than in controls (-4.6 ± 0.9 versus -1.7 ± 0.9 mm/year, respectively, difference of -2.9 [95% CI, -5.3 to -0.6] mm/year, p = 0.015 [TG]).

CONCLUSIONS

Several anthropometric and bone differences exist between children and grandchildren of individuals with OA and controls. If these differences are confirmed in additional studies, it would be important to identify the mechanism so that preventive measures could be developed and implemented to slow or reduce OA development.

CLINICAL RELEVANCE

Differences in growth and bone development may lead to increased loads on cartilage that may predispose offspring to the development of OA. If these differences are confirmed in additional studies, it would be important to identify the mechanism so that preventive measures could be developed and implemented to slow or reduce OA development.

Physical activity after total joint arthroplasty: a narrative review

Background

Total joint arthroplasty (TJA) is a common procedure to treat individuals with hip and knee osteoarthritis. While TJAs are successful in decreasing pain and improving quality of life, it is unclear whether individuals who undergo TJA become more physically active after surgery. It is possible that TJA, by itself, is not sufficient to affect the behavior of patients toward physical activity (PA) participation. To increase PA participation, individuals with TJA may need to be exposed to exercise/behavioral interventions specifically aimed to promote PA (ie, in addition to the surgery).

Objectives

This narrative review aimed to assess the evidence on 1) whether TJAs change PA participation from pre- to postsurgery and 2) whether exercise/behavioral interventions delivered before or after TJA help to promote PA in these patients.

Results

For aim 1, the studies that assessed PA from pre- to post-TJA reported that PA does not change in the first 3 months postsurgery. The results of follow-ups longer than 3 months but shorter than 12 months are contradictory, and the results of follow-ups longer than 12 months provide weak evidence of increased PA. Assessment of changes in PA due to TJA is challenged by the wide variability in demographics, methods used to assess PA, and different pathways of care used across studies. The results for aim 2 were limited by a scarcity of studies that used exercise/behavioral interventions to promote PA.

Conclusion

TJA relieves joint pain and offers a unique opportunity for patients to become more physically active. However, the current evidence is limited and unable to offer definitive results of whether TJA is effective to change PA from pre- to postsurgery. Future large studies in representative samples of patients with TJA are needed to adequately answer this question.

3D Printing and Electrospinning of Composite Hydrogels for Cartilage and Bone Tissue Engineering

Injuries of bone and cartilage constitute important health issues costing the National Health Service billions of pounds annually, in the UK only. Moreover, these damages can become cause of disability and loss of function for the patients with associated social costs and diminished quality of life. The biomechanical properties of these two tissues are massively different from each other and they are not uniform within the same tissue due to the specific anatomic location and function. In this perspective, tissue engineering (TE) has emerged as a promising approach to address the complexities associated with bone and cartilage regeneration. Tissue engineering aims at developing temporary three-dimensional multicomponent constructs to promote the natural healing process. Biomaterials, such as hydrogels, are currently extensively studied for their ability to reproduce both the ideal 3D extracellular environment for tissue growth and to have adequate mechanical properties for load bearing. This review will focus on the use of two manufacturing techniques, namely electrospinning and 3D printing, that present promise in the fabrication of complex composite gels for cartilage and bone tissue engineering applications.

Pioglitazone inhibits advanced glycation end product-induced matrix metalloproteinases and apoptosis by suppressing the activation of MAPK and NF-κB

Apoptosis and degeneration coming mainly from chondrocytes are important mechanisms in the onset and progression of osteoarthritis. Specifically, advanced glycation end products (AGEs) play an important role in the pathogenesis of osteoarthritis. Pioglitazone, a peroxisome proliferator-activated receptor γ (PPARγ) agonist has a protective effect on cartilage. This study aims to evaluate the effect of pioglitazone on AGEs-induced chondrocyte apoptosis and degeneration and their underlying mechanism. The in vitro study shows that AGEs induce cleavage of caspase-3 and PARP, up-regulate MMP-13 expression, enhance chondrocyte apoptosis and down-regulate PPARγ expression in human primary chondrocytes, which is reversed by pioglitazone. Furthermore, AGEs activate phosphorylation of Erk, JNK, and p38, and pioglitazone reverses AGEs-induced phosphorylation of Erk and p38. AGEs-induced degradation of IκBα and translocation of nuclear NF-κB p65 is reversed by pioglitazone. Pretreatment of chondrocytes with SB202190 (p38 inhibitor), SP600125 (JNK inhibitor) and BAY-11-7082 (NF-κB inhibitor) inhibit AGEs-induced apoptosis and degeneration. In vivo experiments suggest that pioglitazone reverses AGEs-induced cartilage degeneration and apoptosis in a mouse model, as demonstrated by HE and Safranin O staining, immunohistochemical analyses of Type II collagen (Col II), metalloproteinases (MMPs) and caspase-3. These findings suggest that pioglitazone, a PPARγ agonist, inhibits AGEs-induced chondrocytes apoptosis and degeneration via suppressing the activation of MAPK and NF-κB.

Osteochondral Tissue Engineering: Translational Research and Turning Research into Products

Osteochondral (OC) defect repair is a significant clinical challenge. Osteoarthritis results in articular cartilage/subchondral bone tissue degeneration and tissue loss, which in the long run results in cartilage/ostecochondral defect formation. OC defects are commonly approached with autografts and allografts, and both these options have found limitations. Alternatively, tissue engineered strategies with biodegradable scaffolds with and without cells and growth factors have been developed. In order to approach regeneration of complex tissues such as osteochondral, advanced tissue engineered grafts including biphasic, triphasic, and gradient configurations are considered. The graft design is motivated to promote cartilage and bone layer formation with an interdigitating transitional zone (i.e., bone-cartilage interface). Some of the engineered OC grafts with autologous cells have shown promise for OC defect repair and a few of them have advanced into clinical trials. This chapter presents synthetic osteochondral designs and the progress that has been made in terms of the clinical translation.

Comparative Effectiveness of Intra-Articular Hyaluronic Acid and Corticosteroid Injections on the Time to Surgical Knee Procedures

BACKGROUND

Use of intra-articular hyaluronic acid (HA) injections to manage knee osteoarthritis (OA) remains controversial because of weak and conflicting evidence. The objective was to evaluate the effectiveness of intra-articular HA injections for knee OA management.

METHODS

A nested cohort of persons with knee OA seeing a specialist was created using a 10% random sample of LifeLink Plus claims (2010-2015) to compare the risk of composite (any) knee surgical interventions, total (TKA)/unicompartmental knee arthroplasty (UKA) and TKA only among HA users and 2 comparison groups: corticosteroid (CS) users and HA/CS nonusers. A high-dimensional propensity score (hdPS) was used to match HA users with CS users and with HA/CS nonusers on background covariates. The risk of surgical interventions among HA users relative to the comparison groups was assessed using Cox proportional hazard models.

RESULTS

Among 13,849 patients, 797 were HA users, 5327 were CS users, and 7725 were HA/CS nonusers. After hdPS matching, the risk of composite surgical interventions did not differ between HA users and HA/CS nonusers (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.67-1.16) and CS users (HR, 0.89; 95% CI, 0.65-1.12). Seven of the 8 sensitivity analyses demonstrated no significant benefit among HA users compared to CS users and HA/CS nonusers. A sensitivity analysis that restricted the study cohort to those who ultimately have knee surgery showed a lower risk of surgery of HA (HR, 0.87; 95% CI, 0.79-0.95).

CONCLUSION

There were no significant differences in the risk of surgical interventions among HA users compared to HA/CS nonusers and CS users after accounting for residual confounding using an hdPS.

Platelet-Rich Plasma for the Management of Hip and Knee Osteoarthritis

PURPOSE OF REVIEW

Knee and hip osteoarthritis (OA) are major public health problems worldwide causing pain, disability and impaired quality of life. This narrative paper discusses platelet-rich plasma (PRP) as a treatment for hip and knee OA, with a focus on evidence from randomised controlled trials (RCTs).

RECENT FINDINGS

Since the first RCT of PRP in 2012, there has been 15 RCTs in knee OA and three in hip OA, mostly comparing PRP to another intra-articular injection therapy, hyaluronic acid. All studies are of low to moderate methodological quality and use variable PRP protocols. In general, results showed that PRP is a safe treatment with potential to provide symptomatic benefit for OA at least in the short term (up to 12 months). Younger patients with less severe disease may be more responsive. There are no RCTs investigating the effects of PRP on OA structural changes. No definitive conclusions can be made about the effects of PRP in OA given methodological concerns and considerable heterogeneity between studies. Further high-quality research is needed to establish the clinical and cost-effectiveness of PRP, the patients most likely to benefit and the optimal PRP protocol.

Efficacy of Intra-articular Injection of a Newly Developed Plasma Rich in Growth Factor (PRGF) Versus Hyaluronic Acid on Pain and Function of Patients with Knee Osteoarthritis: A Single-Blinded Randomized Clinical Trial

Background and objectives:

Knee osteoarthritis is the most common joint disease. We aimed to compare the efficacy and safety of intra-articular injection of a newly developed plasma rich in growth factor (PRGF) versus hyaluronic acid (HA) on pain and function of patients with knee osteoarthritis.

Methods:

In this single-blinded randomized clinical trial, patients with symptomatic osteoarthritis of knee were assigned to receive 2 intra-articular injections of our newly developed PRGF in 3 weeks or 3 weekly injections of HA. Our primary outcome was the mean change from baseline until 2 and 6 months post intervention in scores of visual analog scale, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Lequesne index. We used analysis of variance for repeated-measures statistical test.

Results:

A total of 69 patients entered final analysis. The mean age of patients was 58.2 ± 7.41 years and 81.2% were women. In particular, total WOMAC index decreased from 42.9 ± 13.51 to 26.8 ± 13.45 and 24.4 ± 16.54 at 2 and 6 months in the newly developed PRGF group (within subjects P = .001), and from 38.8 ± 12.62 to 27.8 ± 11.01 and 27.4 ± 11.38 at 2 and 6 months in the HA group (within subjects P = .001), respectively (between subjects P = .631). There was no significant difference between PRGF and HA groups in patients’ satisfaction and minor complications of injection, whereas patients in HA group reported significantly lower injection-induced pain.

Conclusions:

In 6 months follow up, our newly developed PRGF and HA, both are effective options to decrease pain and improvement of function in patients with symptomatic mild to moderate knee osteoarthritis.

Comparison of Meniscal Cell-Mediated and Chondrocyte-Mediated Calcification

Background:

Chondrocytes have been traditionally thought to be responsible for calcium crystal deposits within osteoarthritic knees. Increasing recent experimental evidence suggests that menisci may also play a role. However, the calcifying potential of chondrocytes and meniscal cells derived from same OA patients, and the genes associated with meniscal calcification have never been fully examined.

Objective:

Examine and compare the calcifying potential of articular chondrocytes and meniscal cells derived from same OA patients and identify the calcium crystal type(s) and selected gene expression in OA menisci.

Methods:

Chondrocytes and meniscal cells were isolated from articular cartilage and menisci of OA patients undergoing total knee arthroplasty. Chondrocyte- and meniscal cell-mediated calcification was examined using both monolayer and micromass culture-based assays. Crustal types were examined with histological staining. Levels of Type X Collagen, MMP-13, and ANKH in OA menisci were examined using immunohistochemistry.

Results:

Primary human OA meniscal cells produced calcified deposits at a similar rate compared to OA chondrocytes in-vitro. Histological examinations indicate that both BCP crystals and CPPD crystals are present in the meniscal tissue. Type X collagen, MMP-13, and ANKH were found in human OA menisci and their levels increased with OA severity. In addition, type X collagen was co-localized with calcium crystals.

Conclusion:

These findings suggest that OA meniscal cells have a similar calcifying potential as OA chondrocytes, supporting a pathogenic role of OA menisci in OA.

CK2.1, a bone morphogenetic protein receptor type Ia mimetic peptide, repairs cartilage in mice with destabilized medial meniscus

BACKGROUND

Osteoarthritis (OA) of the knee involves degeneration of articular cartilage of the diarthrodial joints. Current treatment options temporarily relieve the joint pain but do not restore the lost cartilage. We recently designed a novel bone morphogenetic protein receptor type I (BMPRI) mimetic peptide, CK2.1, that activates BMPRIa signaling in the absence of bone morphogenetic protein (BMP). Our previous research demonstrated that CK2.1 induced chondrogenesis in vitro and in vivo; however, it is unknown if CK2.1 restores damaged articular cartilage in vivo. In this study, we demonstrate that CK2.1 induced articular cartilage (AC) repair in an OA mouse model.

METHODS

We designed hyaluronic acid (HA)-based hydrogel particles (HGPs) that slowly release CK2.1. HGP-CK2.1 particles were tested for chondrogenic potency on pluripotent mesenchymal stem cells (C3H10T1/2 cells) and locally injected into the intra-articular capsule in mice with cartilage defects. C57BL/6J mice were operated on to destabilize the medial meniscus and these mice were kept for 6 weeks after surgery to sustain OA-like damage. Mice were then injected via the intra-articular capsule with HGP-CK2.1; 4 weeks after injection the mice were sacrificed and their femurs were analyzed for cartilage defects.

RESULTS

Immunohistochemical analysis of the cartilage demonstrated complete repair of the AC compared to sham-operated mice. Immunofluorescence analysis revealed collagen type IX production along with collagen type II in the AC of mice injected with HGP-CK2.1. Mice injected with phosphate-buffered saline (PBS) and HGP alone had greater collagen type X and osteocalcin production, in sharp contrast to those injected with HGP-CK2.1, indicating increased chondrocyte hypertrophy.

CONCLUSIONS

Our results demonstrate that the slow release HGP-CK2.1 drives cartilage repair without the induction of chondrocyte hypertrophy. The peptide CK2.1 could be a powerful tool in understanding the signaling pathways contributing to the repair process, and also may be used as a potential therapeutic for treating degenerative cartilage diseases such as OA.

Presence of IL-17 in synovial fluid identifies a potential inflammatory osteoarthritic phenotype

Purpose

Osteoarthritis (OA) is a common and heterogeneous arthritic disorder. Patients suffer pain and their joints are characterized by articular cartilage loss and osteophyte formation. Risk factors for OA include age and obesity with inflammation identified as a key mediator of disease pathogenesis. Interleukin-17A (IL-17) is a pro-inflammatory cytokine that has been implicated in inflammatory diseases such as rheumatoid arthritis. IL-17 can upregulate expression of inflammatory cytokines and adipocytokines. The aim of this study was to evaluate IL-17 levels in the synovial fluid of patients with end-stage knee and hip OA in relation to inflammation- and pain-related cytokines and adipocytokines in synovial fluid and serum, and clinical and radiographic disease parameters.

Methods

This is a cross-sectional study of 152 patients undergoing total hip and knee arthroplasty for OA. IL-17, IL-6, leptin, adiponectin, visfatin, resistin, C-C Motif Chemokine Ligand 2 (CCL2), C-C Motif Chemokine Ligand 7 (CCL7) and nerve growth factor (NGF) protein levels were measured in synovial fluid and serum using enzyme-linked immunosorbent assay (ELISA). Baseline characteristics included age, sex, body mass index, co-morbidities, pain and function, and radiographic analyses (OA features, K&L grade, minimal joint space width).

Results

14 patients (9.2%) had detectable IL-17 in synovial fluid. These patients had significantly higher median concentrations of IL-6, leptin, resistin, CCL7 and NGF. Osteophytes, sclerosis and minimum joint space width were significantly reduced in patients with detectable IL-17 in synovial fluid. No differences were found in pain, function and comorbidities. IL-17 concentrations in synovial fluid and serum were moderately correlated (r = 0.482).

Conclusion

The presence of IL-17 in the synovial fluid therefore identifies a substantial subset of primary end-stage OA patients with distinct biological and clinical features. Stratification of patients on the basis of IL-17 may identify those responsive to therapeutic targeting.

A Phase I clinical trial of the knee to assess the correlation of gagCEST MRI, delayed gadolinium-enhanced MRI of cartilage and T2 mapping

PURPOSE

Osteoarthritis (OA) is associated with the loss of glycosaminoglycan (GAG) during disease progression, which can be detected by glycosaminoglycan chemical exchange-dependent saturation transfer (gagCEST) MRI. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) is considered one of the standard methods for GAG quantification in vivo. This Phase I study assessed the correlation between gagCEST MRI and dGEMRIC in determining cartilage GAG concentration. Standard T2 mapping was used as a comparator with the two other methods.

MATERIALS AND METHODS

Eight athletic volunteers with no known knee diseases were recruited in this study. The sagittal images of both knees in each volunteer were obtained by a 3T MRI system. GAG concentration was calculated based on fixed charge density (FCD) within articular cartilage as calculated by T1 values obtained from dGEMRIC sequences. Magnetization transfer ratio asymmetry (MTR_asym) of the CEST spectrum at 1ppm was determined with gagCEST MRI. T2 values were calculated using a multi-echo turbo spin echo (TSE) sequence. The Pearson correlations among MTR_asym were calculated from gagCEST analysis.

RESULTS

There was moderate correlation (correlation coefficient r=0.55) between dGEMRIC and gagCEST MRI results. T2 had a low correlation (r=-0.30) with gagCEST and no correlation with dGEMRIC (r=0.003). Both gagCEST and dGEMRIC were able to distinguish between high GAG concentration cartilage compartments (higher than 210mM) and low GAG cartilage compartments (lower than 210mM).

CONCLUSION

dGEMRIC was shown to be a more accurate and sensitive clinical imaging tool in evaluating cartilage GAG levels in vivo. While GagCEST showed less sensitivity to GAG concentration variations than dGEMRIC, further improvements may yet enable gagCEST to be a clinically robust methodology.

Reduction of friction by recombinant human proteoglycan 4 in IL-1α stimulated bovine cartilage explants

A boundary lubricant attaches and protects sliding bearing surfaces by preventing interlocking asperity-asperity contact. Proteoglycan-4 (PRG4) is a boundary lubricant found in the synovial fluid that provides chondroprotection to articular surfaces. Inflammation of the diarthrodial joint modulates local PRG4 concentration. Thus, we measured the effects of inflammation, with Interleukin-1α (IL-1α) incubation, upon boundary lubrication and PRG4 expression in bovine cartilage explants. We further aimed to determine whether the addition of exogenous human recombinant PRG4 (rhPRG4) could mitigate the effects of inflammation on boundary lubrication and PRG4 expression in vitro. Cartilage explants, following a 7 day incubation with IL-1α, were tested in a disc-on-disc configuration using either rhPRG4 or saline (PBS control) as a lubricant. Following mechanical testing, explants were studied immunohistochemically or underwent RNA extraction for real-time polymerase chain reaction (RT-PCR). We found that static coefficient of friction (COF) significantly decreased to 0.14 ± 0.065 from 0.21 ± 0.059 (p = 0.014) in IL-1α stimulated explants lubricated with rhPRG4, as compared to PBS. PRG4 expression was significantly up regulated from 30.8 ± 19 copies in control explants lubricated with PBS to 3330 ± 1760 copies in control explants lubricated with rhPRG4 (p < 0.001). Explants stimulated with IL-1α displayed no increase in PRG4 expression upon lubrication with rhPRG4, but with PBS as the lubricant, IL-1α stimulation significantly increased PRG4 expression compared to the control condition from 30.8 ± 19 copies to 401 ± 340 copies (p = 0.015). Overall, these data suggest that exogenous rhPRG4 may provide a therapeutic option for reducing friction in transient inflammatory conditions and increasing PRG4 expression. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:580-589, 2017.

Knee osteoarthritis: Therapeutic alternatives in primary care

AIM

To discusses pharmacological and non-pharmacological therapeutic alternatives for managing knee osteoarthritis in primary care by primary health care nurse practitioners.

METHODS

A case example is presented, the evidence-based guideline recommendations of the Osteoarthritis Research Society International and the American Academy of Orthopaedic Surgeons are reviewed, and a plan of care is developed.

RESULTS

Osteoarthritis is the most common form of arthritis seen in primary care, and it is a major public health issue because the aging population and widespread obesity have drastically increased incidence. Osteoarthritis is clinically associated with escalating chronic pain, physical disability, and decreased quality of life. Early diagnosis of mild osteoarthritis in relatively young patients presents an opportunity for primary health care providers to manage pain, increase quality of life, and decrease risk of disability.

CONCLUSION

Primary health care providers can implement these recommendations in their own practices to provide care to patients with knee osteoarthritis based on current best evidence.

Sodium Tungstate for Promoting Mesenchymal Stem Cell Chondrogenesis

Articular cartilage has a limited ability to heal. Mesenchymal stem cells (MSCs) derived from the bone marrow have shown promise as a cell type for cartilage regeneration strategies. In this study, sodium tungstate (Na2WO4), which is an insulin mimetic, was evaluated for the first time as an inductive factor to enhance human MSC chondrogenesis. MSCs were seeded onto three-dimensional electrospun scaffolds in growth medium (GM), complete chondrogenic induction medium (CCM) containing insulin, and CCM without insulin. Na2WO4 was added to the media leading to final concentrations of 0, 0.01, 0.1, and 1 mM. Chondrogenic differentiation was assessed by biochemical analyses, immunostaining, and gene expression. Cytotoxicity using human peripheral blood mononuclear cells (PBMCS) was also investigated. The chondrogenic differentiation of MSCs was enhanced in the presence of low concentrations of Na2WO4 compared to control, without Na2WO4. In the induction medium containing insulin, cells in 0.01 mM Na2WO4 produced significantly higher sulfated glycosaminoglycans, collagen type II, and chondrogenic gene expression than all other groups at day 28. Cells in 0.1 mM Na2WO4 had significantly higher collagen II production and significantly higher sox-9 and aggrecan gene expression compared to control at day 28. Cells in GM and induction medium without insulin containing low concentrations of Na2WO4 also expressed chondrogenic markers. Na2WO4 did not stimulate PBMC proliferation or apoptosis. The results demonstrate that Na2WO4 enhances chondrogenic differentiation of MSCs, does not have a toxic effect, and may be useful for MSC-based approaches for cartilage repair.

Robotics in Arthroplasty: A Comprehensive Review

Robotic-assisted orthopedic surgery has been available clinically in some form for over 2 decades, claiming to improve total joint arthroplasty by enhancing the surgeon's ability to reproduce alignment and therefore better restore normal kinematics. Various current systems include a robotic arm, robotic-guided cutting jigs, and robotic milling systems with a diversity of different navigation strategies using active, semiactive, or passive control systems. Semiactive systems have become dominant, providing a haptic window through which the surgeon is able to consistently prepare an arthroplasty based on preoperative planning. A review of previous designs and clinical studies demonstrate that these robotic systems decrease variability and increase precision, primarily focusing on component positioning and alignment. Some early clinical results indicate decreased revision rates and improved patient satisfaction with robotic-assisted arthroplasty. The future design objectives include precise planning and even further improved consistent intraoperative execution. Despite this cautious optimism, many still wonder whether robotics will ultimately increase cost and operative time without objectively improving outcomes. Over the long term, every industry that has seen robotic technology be introduced, ultimately has shown an increase in production capacity, improved accuracy and precision, and lower cost. A new generation of robotic systems is now being introduced into the arthroplasty arena, and early results with unicompartmental knee arthroplasty and total hip arthroplasty have demonstrated improved accuracy of placement, improved satisfaction, and reduced complications. Further studies are needed to confirm the cost effectiveness of these technologies.

Incorporating Novel Mobile Health Technologies Into Management of Knee Osteoarthritis in Patients Treated With Intra-Articular Hyaluronic Acid: Rationale and Protocol of a Randomized Controlled Trial

Background

Osteoarthritis (OA) of the knee is one of the leading causes of disability in the United States. One relatively new strategy that could be helpful in the management of OA is the use of mHealth technologies, as they can be used to increase physical activity and promote exercise, which are key components of knee OA management.

Objective

Currently, no published data on the use of a mHealth approach to comprehensively monitor physical activity in patients with OA are available, and similarly, no data on whether mHealth technologies can impact outcomes are available. Our objective is to evaluate the effectiveness of mHealth technology as part of a tailored, comprehensive management strategy for patients with knee OA.

Methods

The study will assess the impact of a smartphone app that integrates data from a wearable activity monitor (thereby both encouraging changes in mobility as well as tracking them) combined with education about the benefits of walking on patient mobility. The results from the intervention group will be compared with data from a control group of individuals who are given the same Arthritis Foundation literature regarding the benefits of walking and wearable activity monitors but who do not have access to the data from those monitors. Activity monitors will capture step count estimates and will compare those with patients’ step goals, calories burned, and distance walked. Patients using the novel smartphone app will be able to enter information on their daily pain, mood, and sleep quality. The relationships among activity and pain, activity and mood, and sleep will be assessed, as will patient satisfaction with and adherence to the mobile app.

Results

We present information on an upcoming trial that will prospectively assess the ability of a mobile app to improve mobility for knee OA patients who are treated with intra-articular hyaluronic acid.

Conclusions

We anticipate the results of this study will support the concept that mHealth technologies provide continuous, real-time feedback to patients with OA on their overall level of activity for a more proactive, personalized approach to treatment that may help modify behavior and assist with self-management through treatment support in the form of motivational messages and reminders.