Lifetime medical costs of knee osteoarthritis management in the United States: impact of extending indications for total knee arthroplasty

Mechanisms and therapeutic implications of cellular senescence in osteoarthritis

The development of osteoarthritis (OA) correlates with a rise in the number of senescent cells in joint tissues, and the senescence-associated secretory phenotype (SASP) has been implicated in cartilage degradation and OA. Age-related mitochondrial dysfunction and associated oxidative stress might induce senescence in joint tissue cells. However, senescence is not the only driver of OA, and the mechanisms by which senescent cells contribute to disease progression are not fully understood. Furthermore, it remains uncertain which joint cells and SASP-factors contribute to the OA phenotype. Research in the field has looked at developing therapeutics (namely senolytics and senomorphics) that eliminate or alter senescent cells to stop disease progression and pathogenesis. A better understanding of how senescence contributes to joint dysfunction may enhance the effectiveness of these approaches and provide relief for patients with OA.

Cost-effectiveness of duloxetine for knee OA subjects: the role of pain severity

OBJECTIVE

Establish the impact of pain severity on the cost-effectiveness of generic duloxetine for knee osteoarthritis (OA) in the United States.

DESIGN

We used a validated computer simulation of knee OA to compare usual care (UC) - intra-articular injections, opioids, and total knee replacement (TKR) - to UC preceded by duloxetine in those no longer achieving pain relief from non-steroidal anti-inflammatory drugs (NSAIDs). Outcomes included quality-adjusted life years (QALYs), lifetime medical costs, and incremental cost-effectiveness ratios (ICERs). We considered cohorts with mean ages 57-75 years and Western Ontario and McMaster Osteoarthritis Index (WOMAC) pain 25-55 (0-100, 100-worst). We derived inputs from published data. We discounted costs and benefits 3% annually. We conducted sensitivity analyses of duloxetine efficacy, duration of pain relief, toxicity, and costs.

RESULTS

Among younger subjects with severe pain (WOMAC pain = 55), duloxetine led to an additional 9.6 QALYs per 1,000 subjects (ICER = $88,500/QALY). The likelihood of duloxetine being cost-effective at willingness-to-pay (WTP) thresholds of $50,000/QALY and $100,000/QALY was 40% and 54%. Offering duloxetine to older patients with severe pain led to ICERs >$150,000/QALY. Offering duloxetine to subjects with moderate pain (pain = 25) led to ICERs <$50,000/QALY, regardless of age. Among knee OA subjects with severe pain (pain = 55) who are unwilling or unable to undergo TKR, ICERs were <$50,600/QALY, regardless of age.

CONCLUSIONS

Duloxetine is a cost-effective addition to knee OA UC for subjects with moderate pain or those with severe pain unable or unwilling to undergo TKR. Among younger subjects with severe pain, duloxetine is cost-effective at WTP thresholds >$88,500/QALY.

Clinical Applicability of Adult Human Mesenchymal Stem Cell Therapy in the Treatment of Knee Osteoarthritis

Introduction

Osteoarthritis causes a progressive deterioration to the protective cartilage between the joints leading to chronic pain and disability. This review focuses on the intrinsic potential of MSCs to stabilize and repair the cartilage tissue of the knee joint in knee osteoarthritis (KOA) patients.

Methods

An online search through the PubMed database was conducted, limiting the search to the English language and human clinical trials within the past 5 years. Twenty-one clinical trials passed the inclusion criteria. Combined, those trials involved the participation of 589 patients where the progress of the treatments was monitored between a 4-month to 7-years period. The cartilage volume and defects were observed through an MRI to provide an objective assessment. While the pain and knee function were monitored using KOOS, VAS, and WOMAC scoring scales providing a subjective assessment.

Results

MRI scans obtained from clinical trials demonstrate a slowed progression of cartilage degeneration and early signs of cartilage regeneration in KOA patients at the 12-month follow-up period. No major adverse effects were observed post-intervention. The overall KOOS, WOMAC, and VAS scores in patients receiving MSC treatment were reduced, suggesting subjective improvements in knee function and pain reduction when compared to patients in the placebo group.

Conclusion

The use of MSC therapy is a valid form of treatment for KOA as it targets the disease itself rather than the symptoms. We found MSC therapy in KOA patients to be safe, effective, and feasible in its execution.

Cost-effectiveness of dental antibiotic prophylaxis in total knee arthroplasty recipients with type II diabetes mellitus

Objective

Type II diabetes mellitus (T2DM) is prevalent in knee osteoarthritis (OA) patients undergoing total knee arthroplasty (TKA) and increases risk for prosthetic joint infection (PJI). We examined the cost-effectiveness of antibiotic prophylaxis (AP) before dental procedures to reduce PJI in TKA recipients with T2DM.

Design

We used the Osteoarthritis Policy Model, a validated computer simulation of knee OA, to compare two strategies among TKA recipients with T2DM (mean age 68 years, mean BMI 35.4 kg/m2): 1) AP before dental procedures and 2) no AP. Outcomes included quality-adjusted life expectancy (QALE) and lifetime medical costs. We used published efficacy of AP. We report incremental cost-effectiveness ratios (ICERs) and considered strategies with ICERs below well-accepted willingness-to-pay (WTP) thresholds cost-effective. We conducted sensitivity analyses to examine the robustness of findings to uncertainty in model input parameters. We used a lifetime horizon and healthcare sector perspective.

Results

We found that AP added 1.0 quality-adjusted life-year (QALY) and $66,000 for every 1000 TKA recipients with T2DM, resulting in an ICER of $66,000/QALY. In sensitivity analyses, reduction of the probability of PJI, T2DM-associated risk of infection, or attribution of infections to dental procedures by 50% resulted in ICERs exceeding $100,000/QALY. Probabilistic sensitivity analyses showed that AP was cost-effective in 32% and 58% of scenarios at WTP of $50,000/QALY and $100,000/QALY, respectively.

Conclusions

AP prior to dental procedures is cost-effective for TKA recipients with T2DM. However, the cost-effectiveness of AP depends on the risk of PJI and efficacy of AP in this population.

"I've been to physical therapy before, but not for the knees." A qualitative study exploring barriers and facilitators to physical therapy utilization for knee osteoarthritis

BACKGROUND

Physical therapy (PT) is recommended to reduce pain and improve function. However, only 10%-15% of adults with knee osteoarthritis (OA) use PT in the United States. The purpose of this study was to explore patient-reported barriers and facilitators to PT utilization for knee OA, to understand why PT is underutilized.

METHODS

Qualitative descriptive study using semi-structured interviews was conducted, that is, one-on-one phone interviews with adults from local community centers. Participants were eligible if they were fluent in English and self-reported knee OA (1) over 45 years of age, (2) have activity-related knee pain, and (3) have no morning stiffness or morning stiffness in the knee(s) for ≤30 min. Interviews were audio-recorded and transcribed. To identify barriers and facilitators to PT utilization for knee OA, a coding framework, thematic analysis, and a constant comparative approach were used.

RESULTS

Of 22 participants with health insurance and who participated, 59% were considering PT, 23% refused PT, and 18% used PT for knee OA. Themes identified as either barriers or facilitators for participants were (1) previous experience with PT, (2) physician referral, (3) beliefs about treatment efficacy before and after knee replacement surgery, (4) insurance coverage, and (5) preference to avoid surgery.

CONCLUSION

A previous positive encounter with PT and a physician referral may facilitate PT utilization for adults with knee OA. Knowledge about and access to PT services were not identified as barriers related to PT utilization. Further research is necessary to confirm findings in a broader group of adults with knee OA.

Intra-Articular Injection of Amniotic Membrane and Umbilical Cord Particulate for the Management of Moderate to Severe Knee Osteoarthritis

Objective

To evaluate the long-term benefit of a single injection of amniotic membrane/umbilical cord (AM/UC) particulate in patients with moderate to severe knee osteoarthritis (OA).

Methods

A single-center, investigator-initiated, retrospective study of patients who received intra-articular injection of 100 mg lyophilized and micronized AM/UC for radiographically confirmed, Kellgren–Lawrence (KL) grade 3 or 4 symptomatic knee OA. Data regarding demographics, OA severity, comorbidities, treatment regimens, complications, and patient-reported outcomes were collected and assessed. Patient Global Impression of Change (PGIC) was assessed on a 7-point scale, and Global Perceived Improvement (GPI), expressed as percent improvement relative to baseline, was used to further quantify the degree of symptomatic change. Clinically important response to treatment was assessed at 12 months using simplified OMERACT–OARSI responder criteria.

Results

A total of 42 patients with KL grade 3 (36%) and 4 (64%) knee OA were included for analysis. Prior to injection, patient-rated pain was 6.6 ± 1.5 out of 10 (median: 7, range: 3–10) despite prior treatment with oral/topical NSAIDs (62%) and intra-articular injection(s) of corticosteroids (57%) and/or hyaluronic acid (48%). Twelve months following AM/UC injection, 31 patients (74%) reported significant clinical improvement via PGIC, and the OMERACT–OARSI treatment response rate was 81% (34/42). GPI of pain and function was 62 ± 24%, 69 ± 27%, 69 ± 27%, and 64 ± 31% at 1, 3, 6, and 12 months, respectively. Symptomatic improvement was maintained for an average duration of 12.1 ± 4.5 months (median: 12, range: 3–22). One patient developed swelling in the knee within 36 hours of injection. No other adverse events or complications were reported.

Conclusion

Intra-articular injection of AM/UC particulate may be effective in alleviating pain and improving function in patients with moderate to severe knee OA, with the potential to delay total knee replacement for up to 12 months.

A self-management support intervention on knee functional status and health-related quality of life among middle-age women: A randomized controlled trial

AIM

To determine the effectiveness of a self-management support intervention on knee functional status and health-related quality of life among middle-age women with knee osteoarthritis.

DESIGN

Randomized controlled trial.

METHODS

The participants were 40 middle-aged women who had been clinically diagnosed with knee osteoarthritis for more than 3 months and randomly assigned into intervention and control groups equally. After IRB approval code 02-05-2562 was obtained, data collection was carried out from July - November 2019 at the Outpatient Department of Orthorpedics, Thasala Hospital, Thailand. The modified Thai version of the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and the Short Form Survey (SF-36) were used to measure knee functional status and health-related quality of life at baseline (T1), immediately after completing the intervention (T2) and 4 weeks after the intervention (T3). The participants in the intervention group received a self-management support program developed by the researcher based on the Individual and Family Self-Management Theory and a review of related literature plus routine care. The implementation consisted of eight sessions over 4 weeks. The control group received only routine care from the hospital. Two-way repeated measure ANOVAs were used to analyze the data.

RESULTS

The findings revealed that the participants in the intervention group had better knee functional status and HRQOL than those in the control group at follow-up. Additionally, in the intervention group, both knee functional status and HRQOL significantly improved from pre- to post-intervention and follow-up.

CONCLUSIONS

The findings indicate that this self-management support intervention is effective.

IMPACT

For women, the prevalence rate of knee OA rises dramatically post-menopause due to lower oestrogen levels. Policy makers and healthcare providers could obtain and promote this intervention as part of standard practice. This should lead to improved knee functional status and HRQOL among middle-aged women. Thai Trial Registration number: TCTR20191223003. on February 5th, 2019.

An anatomical neurovascular study for procedures targeting peri-articular nerves in patients with anterior knee pain

BACKGROUND

Radiofrequency ablation (RFA) of the articular branches innervating the anterior knee capsule has been studied as a possible alternative to surgery for degenerative arthritis. However, the neurovascular topography of the anterior knee capsule remains unclear.

METHODS

One leg from each of the 20 formalin-embalmed cadaveric specimens was investigated. Modified ablation points (MAPs) were evaluated for a possible alternative for conventional target points (CAPs).

RESULTS

For the nerve to vastus medialis (NVM), the probability of identifying the nerve was higher at MAP compared with CAP (62.5% vs. 25%). The mean shortest distance from the nerve was shorter at MAP compared with CAP (18.0 mm vs. 29.9 mm). The probabilities and distances for other nerves were not significantly different between the points. However, the probability of identifying the artery was significantly lower at MAPs compared with CAPs for arteries (0%, 5.3%, and 0% vs. 84.2%, 84.2%, and 73.3% for superior medial genicular, superior lateral genicular, and inferior medial genicular artery, respectively). For the recurrent peroneal nerve (RPN), a new target point was set in MAPs.

CONCLUSIONS

The current landmark for genicular nerve procedures may not accurately target the correct nerve position, or reduce the risk for vessel damage. A more proximal target may reduce complications and increase the probability of successful procedures, although clinical correlation is needed.

Of mice and men: converging on a common molecular understanding of osteoarthritis

Despite an increasing burden of osteoarthritis in developed societies, target discovery has been slow and there are currently no approved disease-modifying osteoarthritis drugs. This lack of progress is due in part to a series of misconceptions over the years: that osteoarthritis is an inevitable consequence of ageing, that damaged articular cartilage cannot heal itself, and that osteoarthritis is driven by synovial inflammation similar to that seen in rheumatoid arthritis. Molecular interrogation of disease through ex-vivo tissue analysis, in-vitro studies, and preclinical models have radically reshaped the knowledge landscape. Inflammation in osteoarthritis appears to be distinct from that seen in rheumatoid arthritis. Recent randomised controlled trials, using treatments repurposed from rheumatoid arthritis, have largely been unsuccessful. Genome-wide studies point to defects in repair pathways, which accords well with recent promise using growth factor therapies or Wnt pathway antagonism. Nerve growth factor has emerged as a robust target in osteoarthritis pain in phase 2-3 trials. These studies, both positive and negative, align well with those in preclinical surgical models of osteoarthritis, indicating that pathogenic mechanisms identified in mice can lead researchers to valid human targets. Several novel candidate pathways are emerging from preclinical studies that offer hope of future translational impact. Enhancing trust between industry, basic, and clinical scientists will optimise our collective chance of success.

Knee Osteoarthritis Treatment Costs in the Medicare Patient Population

BACKGROUND

Several nonoperative options have been recommended for the treatment of knee osteoarthritis (OA), with varying degrees of evidence. Adhering to the American Academy of Orthopaedic Surgeons clinical practice guidelines has been suggested to decrease direct treatment costs by 45% in the year before knee arthroplasty, but this does not consider the cost of the entire episode of care, including the cost of surgery and postsurgery care.

OBJECTIVES

To analyze the total treatment costs after a diagnosis of knee OA, as well as the proportion of arthroplasty interventions as part of the total knee OA-related costs, and whether the total costs differed for patients who received intra-articular hyaluronic acid and/or had knee arthroplasty.

METHODS

We identified patients newly diagnosed with knee OA using the 5% Medicare data sample from January 2010 to December 2015. Patients were excluded if they were aged <65 years, had incomplete claim history, did not reside in any of the 50 states, had claim history <12 months before knee OA diagnosis, or did not enroll in Medicare Part A and Part B. The study analyzed knee OA-related costs from a payer perspective in terms of reimbursements provided by Medicare, as well as the time from the diagnosis of knee OA to knee arthroplasty for patients who had knee arthroplasty, and the time from the first hyaluronic acid injection to knee arthroplasty for those who received the injection. We compared patients who received hyaluronic acid and those who did not receive hyaluronic acid injections. Patients who received hyaluronic acid injection who subsequently had knee arthroplasty were also compared with those who did not have subsequent knee arthroplasty.

RESULTS

Of the 275,256 patients with knee OA, 45,801 (16.6%) received a hyaluronic acid injection and 35,465 (12.9%) had knee arthroplasty during the study period. The median time to knee arthroplasty was 16.4 months for patients who received hyaluronic acid versus 5.7 months for those who did not receive hyaluronic acid. Non-arthroplasty-related therapies and knee arthroplasty accounted for similar proportions of knee OA-related costs, with hyaluronic acid injection comprising 5.6% of the total knee OA-related costs. For patients who received hyaluronic acid injections and subsequently had knee arthroplasty, hyaluronic acid injection contributed 1.8% of the knee OA-related costs versus 76.6% of the cost from knee arthroplasty. Patients who received hyaluronic acid injections and did not have knee arthroplasty incurred less than 10% of the knee OA-related costs that patients who had surgery incurred.

CONCLUSION

Although limiting hyaluronic acid use may reduce the knee OA-related costs, in this study hyaluronic acid injection only comprised a small fraction of the overall costs related to knee OA. Among patients who had knee arthroplasty, those who received treatment with hyaluronic acid had surgery delayed by a median of 10.7 months and associated costs for a significant period. The ability to delay or avoid knee arthroplasty altogether can have a substantial impact on healthcare costs.

Single-leg forward hopping exposures adversely affect knee joint health among persons with unilateral lower limb loss: A predictive model

Single-leg hopping is an atypical, yet convenient, method of ambulation for individuals who have sustained unilateral lower limb-loss. Hopping is generally discouraged by therapists but many patients report hopping, and the potential deleterious effects of frequent hopping on knee joint health remains unclear. Mechanical fatigue due to repeated exposures to increased or abnormal loading on the intact limb is thought to be a primary contributor to the high prevalence of knee osteoarthritis among individuals with unilateral lower limb amputation. We aimed to compare knee joint mechanics between single-leg hopping and walking at self-selected paces among individuals with unilateral lower limb-loss, and estimated the associated probability of knee cartilage failure. Thirty-two males with traumatic unilateral lower limb-loss (22 transtibial, 10 transfemoral) hopped and walked at a self-selected pace along a 15-m walkway. Peak knee moments were input to a phenomenological model of cartilage fatigue to estimate the damage and long-term failure probability of the medial knee cartilage when hopping vs. walking. We estimate that each hop accumulates as much damage as at least 8 strides of walking (p < 0.001), and each meter of hopping accumulates as much damage as at least 12 m of walking (p < 0.001). The 30-year failure probability of the medial knee cartilage exceeded a "coin-flip" chance (50%) when performing more than 197 hops per day. Although a convenient mode of ambulation for persons with unilateral lower limb-loss, to mitigate risk for knee osteoarthritis it is advisable to minimize exposure to single-leg forward hopping.

Knee OA cost comparison for hyaluronic acid and knee arthroplasty

BACKGROUND

Limiting treatment to those recommended by the American Academy of Orthopaedic Surgeon Clinical Practice Guidelines has been suggested to decrease costs by 45% in the year prior to total knee arthroplasty, but this only focuses on expenditures leading up to, but not including, the surgery and not the entire episode of care. We evaluated the treatment costs following knee osteoarthritis (OA) diagnosis and determined whether these are different for patients who use intra-articular hyaluronic acid (HA) and/or knee arthroplasty.

METHODS

Claims data from a large commercial database containing de-identified data of more than 100 million patients with continuous coverage from 2012 to 2016 was used to evaluate the cumulative cost of care for over 2 million de-identified members with knee OA over a 4.5-year period between 2011 and 2015. Median cumulative costs were then stratified for patients with or without HA and/or knee arthroplasty.

RESULTS

Knee OA treatment costs for 1,567,024 patients over the 4.5-year period was $6.60 billion (mean $4210/patient) as calculated by the authors. HA and knee arthroplasty accounted for 3.0 and 61.5% of the overall costs, respectively. For patients who underwent knee arthroplasty, a spike in median costs occurred sooner for patients without HA use (around the 5- to 6-month time point) compared to patients treated with HA (around the 16- to 17-month time point).

CONCLUSIONS

Non-arthroplasty therapies, as calculated by the authors, accounted for about one third of the costs in treating knee OA in our cohort. Although some have theorized that limiting the use of HA may reduce the costs of OA treatment, HA only comprised a small fraction (3%) of the overall costs. Among patients who underwent knee arthroplasty, those treated with HA experienced elevated costs from the surgery later than those without HA, which reflects their longer time to undergoing knee arthroplasty. The ability to delay or avoid knee arthroplasty altogether can have a substantial impact on the cost to the healthcare system.

Bone marrow concentrate injections for the treatment of osteoarthritis: evidence from preclinical findings to the clinical application

Purpose

To investigate the available literature on the use of bone marrow aspirate concentrate (BMAC) and summarize the current evidence supporting its potential for the injective treatment of joints affected by osteoarthritis (OA).

Methods

A systematic literature search was conducted on three electronic databases (PubMed, Embase, and Cochrane Library) in April 2020, using the following string: “((bone marrow concentrate) OR (BMC) OR (bone marrow aspirate concentrate) OR (BMAC)) AND (osteoarthritis)”, and inclusion criteria: clinical and preclinical (animal) studies of any level of evidence, written in English language, and evaluating the intra-articular or subchondral use of BMAC for the injective treatment of OA joints.

Results

The publication trend remarkably increased over time. A total of 22 studies were included in the qualitative data synthesis: four preclinical studies and 18 clinical studies, for a total number of 4626 patients. Safety was documented by all studies, with a low number of adverse events. An overall improvement in pain and function was documented in most of the studies, but the clinical studies present significant heterogeneity, few patients, short-term follow-up, and overall poor methodology.

Conclusion

There is a growing interest in the field of BMAC injections for the treatment of OA, with promising results in preclinical and clinical studies in terms of safety and effectiveness. Nevertheless, the current knowledge is still preliminary. Preclinical research is still needed to optimize BMAC use, as well as high-level large controlled trials to better understand the real potential of BMAC injections for the treatment of patients affected by OA.

Sex-Modified Effects of Depression, Low Back Pain, and Comorbidities on Pain After Total Knee Arthroplasty for Osteoarthritis

OBJECTIVE

The influence of sex on post-total knee arthroplasty (TKA) outcomes has been variable in the literature. Though sex is often reported as an averaged effect, we undertook this study to investigate whether sex modified the influence of presurgery characteristics on post-TKA knee pain.

METHODS

This was a prospective study with data derived from 477 TKA osteoarthritis patients (279 women, 198 men). Questionnaires were completed presurgery and at 3 months postsurgery. The association between 3-month post-TKA knee pain and presurgery covariates (body mass index, comorbidity count, symptomatic joint count, low back pain, knee pain, and depressive symptoms) was assessed by linear regression. Sex-specific effects were evaluated using interactions.

RESULTS

Women had significantly worse presurgery knee pain, joint count, and depressive symptoms, and worse postsurgery knee pain, than men. With simple covariate adjustment, no sex effect on pain was found. However, sex was found to moderate the effects of comorbidities (worse for women [P = 0.013]), presence of low back pain (worse for men [P = 0.003]), and depressive symptoms (worse for men [P < 0.001]) on postsurgery pain. Worse presurgery pain was associated with worse postsurgery pain similarly for women and men.

CONCLUSION

The influence of some patient factors on early post-TKA pain cannot be assumed to be the same for women and men; average effects may mask underlying associations. Results suggest a need to consider sex differences in understanding TKA outcomes, which may have important implications for prognostic tool development in TKA.

Can We Predict Severity of Osteoarthritis of Knees and Compartmental Involvement Based on a Set of Predefined Clinical Questions in Patients of Knee Pain?

BACKGROUND

We investigated whether the severity of Osteoarthritis (OA) knees can be predicted based on a set of predefined clinical questions (PCQs) about activities of daily living (ADL). We studied the association of demographic factors and advanced radiographic OA (KL 3 and 4) and the relationship between various physical activities and radiographic involvement of knee joint compartments based on PCQs.

MATERIALS AND METHODS

Demographic data, radiographic grading of knee OA and PCQs score, were obtained prospectively. Patients' responses to PCQs were marked as scores-that were predefined and graded according to the severity of knee pain. Radiographic knee OA grades were dichotomized and patients were classified as either negative (KL grade 1, 2) or positive (KL grade 3, 4). Multivariate logistic regression was performed to obtain the adjusted odds for total PCQs score in relation with positive radiographic OA considering confounders like age, gender and BMI in the model. Log odds score (LOS) were obtained and ROC analysis was performed on scores to obtain the cut-off value for the screening of knee OA in patients of knee pain.

RESULTS

Age and BMI were significantly negatively correlated with PCQs score (r = - 0.473; P < 0.0001 and r = - 0.136; P = 0.046). PCQs scores were significantly lower in females (P = 0.031). Total PCQs score had corresponding OR of 0.901 (P = 0.002) towards knee OA after adjusting for age, gender and BMI. Multivariate model-based LOS resulted in a cut-off of 1.315, which had a sensitivity of 85.5%, specificity of 66.7% and PPV of 92.7%.

CONCLUSION

Severity of knee OA can be predicted based on PCQs. PCQs can predict severity of knee OA and patellofemoral or medial tibiofemoral compartment without radiographs. LOS based on demographics and total PCQs score can be developed as a screening tool for advanced knee OA.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

Level I, systematic review.

A Decline in Walking Speed Is Associated With Incident Knee Replacement in Adults With and at Risk for Knee Osteoarthritis

OBJECTIVE

To determine if a 1-year change in walking speed is associated with receiving an incident knee replacement during the following year in adults with and at risk for knee osteoarthritis (OA).

METHODS

Using data from the Osteoarthritis Initiative, we determined a 1-year change in the 20-meter walk speed from 3 observation periods (i.e., 0-12, 12-24, and 24-36 months). We operationally defined 1-year change in walking speed as either (1) decline: ≤ -0.1 m/s change, (2) no change: between -0.1 and 0.1 m/s change, and (3) increase: ≥ 0.1 m/s change. Incident knee replacement was defined using each subsequent 1-year period (i.e., 12-24, 24-36, and 36-48 months). Combining data from the 3 observation periods, we performed a Poisson regression with robust error variance to determine the relative risk between a change in walking speed (exposure) and incident knee replacement over the following year (outcome).

RESULTS

Of the 4264 participants included within this analysis (11,311 total person visits), 115 (3%) adults received a knee replacement. Decline in walking speed was associated with a 104% increase in risk [adjusted relative risk (RR) 2.04, 95% CI 1.40-2.98], while an increase in walking speed associated with a 55% decrease in risk (RR 0.45; 95% CI 0.22-0.93) of incident knee replacement in the following year compared to a person with no change in walking speed.

CONCLUSION

A 1-year decline in walking speed is associated with an increased risk, while a 1-year increase in walking speed is associated with a decreased risk of future incident knee replacement.

Long-term clinical and economic outcomes of a short-term physical activity program in knee osteoarthritis patients

OBJECTIVE

Physical activity (PA) in the US knee osteoarthritis (OA) population is low, despite well-established health benefits. PA program implementation is often stymied by sustainability concerns. We sought to establish parameters that would make a short-term (3-year efficacy) PA program a cost-effective component of long-term OA care.

METHOD

Using a validated computer microsimulation (Osteoarthritis Policy Model), we examined the long-term clinical (e.g., comorbidities averted), quality of life (QoL), and economic impacts of a 3-year PA program, based upon the SPARKS (Studying Physical Activity Rewards after Knee Surgery) Trial, for inactive knee OA patients. We determined the cost, efficacy, and impact of PA on QoL and medical costs that would make a PA program a cost-effective addition to OA care.

RESULTS

Among the 14 million with knee OA in the US, >4 million are inactive. Participation of 10% in the modeled PA program could save 200 cases of cardiovascular disease, 400 cases of diabetes, and 6,800 quality-adjusted life-years (QALYs). The program had an incremental cost-effectiveness ratio (ICER) of $16,100/QALY. Tripling PA program cost ($860/year) raised the ICER to $108,300/QALY; varying QoL benefits from PA yielded ICERs of $8,800/QALY-$99,900/QALY; varying background cost savings from PA did not qualitatively impact ICERs. Offering the PA program to any adults with knee OA (not only inactive) yielded $31,000/QALY.

CONCLUSION

A PA program with 3-year efficacy in the knee OA population carried favorable long-term clinical and economic benefits. These results offer justification for policymakers and payers considering a PA intervention incorporated into knee OA care.

Demographic Tendencies and Hospitalization Outcomes Among Inpatient Admissions of Osteoarthritis in the Midwest: A 2016 State Inpatient Database Study

Objective

To assess the inpatient prevalence of osteoarthritis in a Midwestern state and to identify trends in demographics and hospital outcomes.

Methods

The Wisconsin State Inpatient Sample Database (2016) was queried to identify hospitalization records with a primary diagnosis of osteoarthritis. Bivariate correlation, descriptive statistics, and single-layer mean comparison were used for categorical and continuous data within the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) sub-groups.

Results

In 2016, there were 64,805 admissions of osteoarthritis. The most common (>0.09%) were the right knee osteoarthritis (24.5%), left knee osteoarthritis (23%), right hip osteoarthritis (16.9%), left hip osteoarthritis (14.3%), knee unspecified osteoarthritis (11.5%), bilateral knees osteoarthritis (7%), and right shoulder osteoarthritis (2%). The mean age on admission was 67 years for each hip osteoarthritis, 66 years for each knee osteoarthritis, and 69 years for right shoulder osteoarthritis. The mean length of stay was 3.15 days for bilateral knee osteoarthritis and 1.92 days for the right shoulder osteoarthritis. Total inpatient charges and in-hospital mortality were highest in right shoulder osteoarthritis (USD 52,699.40 [0.6%]; N = 6), and total charges were lowest in right and left hip osteoarthritis (44,689.54 and 44,427.33, respectively). A greater frequency of females and Caucasians was consistently admitted within each of the included ICD-10-CM OA sub-groupings. Age was correlated with charge in the left hip osteoarthritis (r = 0.050) and right shoulder osteoarthritis (r = 0.068), and was negatively correlated with charge in the bilateral knee osteoarthritis (r = -0.115), right knee osteoarthritis (r = -0.054), and left knee osteoarthritis (r = -0.060).

Conclusions

In Wisconsin, with somewhat of a generalizability to other Midwestern states, attention should be given to Caucasian, elderly, and female patients with osteoarthritis of the hip and knee. Further studies are needed to broaden the understanding of cost utilization, how charges and hospital stay compare nationwide, and where preventative efforts are needed.

Amniotic Suspension Allograft Modulates Inflammation in a Rat Pain Model of Osteoarthritis

Osteoarthritis (OA) affects over 301 million adults worldwide. Inflammation is a recognized component of the OA process; two potent pro-inflammatory cytokines involved in OA are interleukin-1β and tumor necrosis factor-α. Placental-derived tissues and fluids are known to contain anti-inflammatory and immunomodulatory cytokines and growth factors. The objective of this study was to evaluate the anti-inflammatory effects of amniotic suspension allograft (ASA) in an in vivo model of OA; we evaluated pain, function, and cytokine levels following ASA treatment in the rat monosodium iodoacetate (MIA) OA pain model. Rats were injected with 2 mg of MIA, which causes pain, cartilage degeneration, and inflammation, followed by treatment with saline, triamcinolone (positive control), or ASA 7 days following disease induction with MIA. Behavioral assays, including gait analysis, mechanical pain threshold, incapacitance, and swelling were evaluated, along with histology and serum and synovial fluid biomarkers. Treatment with ASA resulted in significant improvements in pain threshold, while weight bearing aversion and swelling were significantly decreased. There were no differences between groups in total joint score after histological grading. Serum biomarkers did not show differences, indicating a lack of systemic response; however, synovial fluid levels of IL-10 were significantly increased in animals treated with ASA. ASA treatment significantly reduced pain, weight-bearing aversion and swelling. This study provides mechanistic data regarding potential therapeutic effects of ASA in OA and preliminary evidence of the anti-inflammatory nature of ASA. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:1141-1149, 2020.

GSK3787-Loaded Poly(Ester Amide) Particles for Intra-Articular Drug Delivery

Osteoarthritis (OA) is a debilitating joint disorder affecting more than 240 million people. There is no disease modifying therapeutic, and drugs that are used to alleviate OA symptoms result in side effects. Recent research indicates that inhibition of peroxisome proliferator-activated receptor δ (PPARδ) in cartilage may attenuate the development or progression of OA. PPARδ antagonists such as GSK3787 exist, but would benefit from delivery to joints to avoid side effects. Described here is the loading of GSK3787 into poly(ester amide) (PEA) particles. The particles contained 8 wt.% drug and had mean diameters of about 600 nm. Differential scanning calorimetry indicated the drug was in crystalline domains in the particles. Atomic force microscopy was used to measure the Young's moduli of individual particles as 2.8 MPa. In vitro drug release studies showed 11% GSK3787 was released over 30 days. Studies in immature murine articular cartilage (IMAC) cells indicated low toxicity from the drug, empty particles, and drug-loaded particles and that the particles were not taken up by the cells. Ex vivo studies on murine joints showed that the particles could be injected into the joint space and resided there for at least 7 days. Overall, these results indicate that GSK3787-loaded PEA particles warrant further investigation as a delivery system for potential OA therapy.

The Association Between Daily Physical Activity and Pain Among Patients with Knee Osteoarthritis: The Moderating Role of Pain Catastrophizing

OBJECTIVE

The primary objective of this study was to examine the day-to-day association between physical activity and pain intensity among a sample of patients with knee osteoarthritis (KOA) and the potential moderation of this association by negative cognitive processes.

METHODS

In this micro-longitudinal daily diary study, KOA patients (N = 121) completed questionnaires assessing pain (Brief Pain Inventory) and psychosocial functioning (pain catrophizing scale, WOMAC McMaster Universities Osteoarthritis Index function, Patient-Reported Outcomes Measurement Information System [PROMIS; anxiety and depression], the Godin-Shephard Leisure-Time Physical Activity questionnaire, the six-minute walking test) and were then asked to report their levels of physical activity and pain intensity once per day for a period of seven days using an electronic diary.

RESULTS

Multilevel modeling analyses indicated that day-to-day increases in physical activity were associated with heightened levels of pain intensity (B = 0.13 SE = 0.03, P < 0.001). In addition, it was revealed that the association between physical activity and pain intensity was moderated by catastrophizing (B = -0.01 SE = 0.002, P < 0.05), with patients scoring higher in catastrophizing showing a relatively stronger link between day-to-day physical activity and increased knee pain. This effect was specific to catastrophizing, as depression and anxiety did not moderate the activity-pain relationship (P > 0.05).

CONCLUSIONS

Our findings suggest that increases in daily physical activity are associated with concurrent increases in KOA patients' levels of knee pain, particularly among patients reporting higher levels of pain catastrophizing. These results may have clinical implications for the design and testing of interventions targeted at reducing catastrophizing and increasing physical activity among patients with chronic osteoarthritis pain.

Correlation network analysis shows divergent effects of a long-term, high-fat diet and exercise on early stage osteoarthritis phenotypes in mice

BACKGROUND

Obesity increases knee osteoarthritis (OA) risk through metabolic, inflammatory, and biomechanical factors, but how these systemic and local mediators interact to drive OA pathology is not well understood. We tested the effect of voluntary running exercise after chronic diet-induced obesity on knee OA-related cartilage and bone pathology in mice. We then used a correlation-based network analysis to identify systemic and local factors associated with early-stage knee OA phenotypes among the different diet and exercise groups.

METHODS

Male C57BL/6J mice were fed a defined control (10% kcal fat) or high fat (HF) (60% kcal fat) diet from 6 to 37 weeks of age. At 25 weeks, one-half of the mice from each diet group were housed in cages with running wheels for the remainder of the study. Histology, micro computed tomography, and magnetic resonance imaging were used to evaluate changes in joint tissue structure and OA pathology. These local variables were then compared to systemic metabolic (body mass, body fat, and glucose tolerance), inflammatory (serum adipokines and inflammatory mediators), and functional (mechanical tactile sensitivity and grip strength) outcomes using a correlation-based network analysis. Diet and exercise effects were evaluated by two-way analysis of variance.

RESULTS

An HF diet increased the infrapatellar fat pad size and posterior joint osteophytes, and wheel running primarily altered the subchondral cortical and trabecular bone. Neither HF diet nor exercise altered average knee cartilage OA scores compared to control groups. However, the coefficient of variation was ≥25% for many outcomes, and some mice in both diet groups developed moderate OA (≥33% maximum score). This supported using correlation-based network analyses to identify systemic and local factors associated with early-stage knee OA phenotypes. In wheel-running cohorts, an HF diet reduced the network size compared to the control diet group despite similar running distances, suggesting that diet-induced obesity dampens the effects of exercise on systemic and local OA-related factors. Each of the 4 diet and activity groups showed mostly unique networks of local and systemic factors correlated with early-stage knee OA.

CONCLUSION

Despite minimal group-level effects of chronic diet-induced obesity and voluntary wheel running on knee OA pathology under the current test durations, diet and exercise substantially altered the relationships among systemic and local variables associated with early-stage knee OA. These results suggest that distinct pre-OA phenotypes may exist prior to the development of disease.

Cost-Effectiveness of Diet and Exercise for Overweight and Obese Patients With Knee Osteoarthritis

OBJECTIVE

The Intensive Diet and Exercise for Arthritis (IDEA) trial showed that an intensive diet and exercise (D+E) program led to a mean 10.6-kg weight reduction and 51% pain reduction in patients with knee osteoarthritis (OA). The aim of the current study was to investigate the cost-effectiveness of adding this D+E program to treatment in overweight and obese (body mass index >27 kg/m² ) patients with knee OA.

METHODS

We used the Osteoarthritis Policy Model to estimate quality-adjusted life-years (QALYs) and lifetime costs for overweight and obese patients with knee OA, with and without the D+E program. We evaluated cost-effectiveness with the incremental cost-effectiveness ratio (ICER), a ratio of the differences in lifetime cost and QALYs between treatment strategies. We considered 3 cost-effectiveness thresholds: $50,000/QALY, $100,000/QALY, and $200,000/QALY. Analyses were conducted from health care sector and societal perspectives and used a lifetime horizon. Costs and QALYs were discounted at 3% per year. D+E characteristics were derived from the IDEA trial. Deterministic and probabilistic sensitivity analyses (PSAs) were used to evaluate parameter uncertainty and the effect of extending the duration of the D+E program.

RESULTS

In the base case, D+E led to 0.054 QALYs gained per person and cost $1,845 from the health care sector perspective and $1,624 from the societal perspective. This resulted in ICERs of $34,100/QALY and $30,000/QALY. In the health care sector perspective PSA, D+E had 58% and 100% likelihoods of being cost-effective with thresholds of $50,000/QALY and $100,000/QALY, respectively.

CONCLUSION

Adding D+E to usual care for overweight and obese patients with knee OA is cost-effective and should be implemented in clinical practice.

A comparison of 4-year total medical care costs, adverse outcomes, and opioid/prescription analgesic use for 3 knee osteoarthritis pain treatments: Intra-articular hyaluronic acid, intra-articular corticosteroids, and knee arthroplasty

OBJECTIVES

To compare the medical costs associated with treatments for knee osteoarthritis (OA): intra-articular corticosteroids (ICS) and intra-articular hyaluronic acid (IHA) primarily, and ICS/IHA vs knee arthroplasty (TKA) secondarily.

METHODS

This was a retrospective analysis of an insurance claims database. Eligible members had diagnosed OA and no claims for ICS, IHA, or TKA during the 6-18-month look-back period. Cohorts of interest over the 4-year observation period were: patients who received ICS only, those who received IHA only, and those who received TKA only. Outcomes assessed included: (1) total allowed medical costs, (2) claims for pre-specified, treatment-related adverse outcomes and costs, and (3) opioid and/or prescription analgesic use and costs. Data extraction began on the date of the first ICS, IHA, or TKA in 2013 until December 31, 2017.

RESULTS

Of the 260,828 patients who qualified, 126,831 were taking monotherapy (IHA=3703, ICS=117,588, TKA = 5540). Adjusted 4-year per patient per month (PPPM) costs were lowest in the IHA cohort ($733); PPPM costs were $1230 in the ICS cohort and $1548 in the TKA cohort. A smaller percentage of patients in the IHA (7.1%) vs ICS (8.4%) or TKA cohort (11.8%) experienced any of the pre-specified adverse outcomes. Adverse outcome-related costs in the IHA cohort were lower ($19.91) than costs in the ICS ($32.18) and TKA cohorts ($31.12). Per-patient opioid and analgesic prescriptions were consistently and significantly lower in the IHA (range, 0.70-0.96) vs ICS cohort (range, 2.0-2.26) for Years 1 through 4. Usage rates were significantly lower in the IHA cohort vs TKA cohort in Year 1 (0.96 vs 4.77) and not different in Years 2 through 4 (TKA range, 0.76-1.08). In Year 1, opioid and prescription analgesic costs were significantly lower in the IHA vs ICS and TKA cohorts ($3.45 vs $11.14 and $12.82). After Year 1, opioid and prescription analgesic costs were significantly higher in the ICS (range, $13.83-15.96) vs IHA (range, $3.02-3.87) and TKA cohorts (range, $3.43-4.97).

CONCLUSIONS

Patients in the IHA cohort had lower total medical care costs, fewer adverse outcomes, and lower use/costs of opioids and prescription analgesics vs patients in the ICS and TKA cohorts. Reducing total medical care costs and minimizing opioid/analgesic use should be a treatment goal when selecting therapies for patients with knee OA.

Budget Impact of Funding an Intensive Diet and Exercise Program for Overweight and Obese Patients With Knee Osteoarthritis

Objective

Diet and exercise (D+E) for knee osteoarthritis (OA) is effective and cost‐effective. However, cost‐effectiveness does not imply affordability; the impact of knee OA–specific D+E programs on insurer budgets is unknown.

Methods

We estimated changes in undiscounted medical expenditures (2016 US dollars) with and without a D+E program. We accounted for both additional program outlays and potential savings from reduced use of other knee OA treatments and from reduced incidence of comorbidities. We adopted the perspective of a representative commercial insurance plan covering 200 000 individuals aged 25 to 64 years and a representative Medicare Advantage plan covering 200 000 Medicare‐eligible individuals aged 65 years and older. We used the Osteoarthritis Policy Model, a validated microsimulation model of knee OA, to model D+E efficacy (measured by pain and weight reduction), adherence, and price based on the Intensive Diet and Exercise for Arthritis (IDEA) trial. In sensitivity analyses, we varied time horizon, D+E efficacy, and D+E price.

Results

Over 3 years, the D+E program increased spending by $752 200 ($0.10 per member per month [PMPM]) in the commercial plan and by $6.0 million ($0.84 PMPM) in the Medicare plan. Over 3 years, the D+E program reduced opioid use by 6% and 5% and reduced total knee replacements by 5% and 4% in the commercial and Medicare plans, respectively. Expenses were higher in the Medicare plan because it had more patients with knee OA than the commercial plan.

Conclusion

Although there is no established threshold to define affordability, a D+E program for knee OA would likely produce expenditures comparable with outlays for other health‐promotion interventions.

Cost-effectiveness of total knee replacement in addition to non-surgical treatment: a 2-year outcome from a randomised trial in secondary care in Denmark

OBJECTIVE

To assess the 24-month cost-effectiveness of total knee replacement (TKR) plus non-surgical treatment compared with non-surgical treatment with the option of later TKR if needed.

METHODS

100 adults with moderate-to-severe knee osteoarthritis found eligible for TKR by an orthopaedic surgeon in secondary care were randomised to TKR plus 12 weeks of supervised non-surgical treatment (exercise, education, diet, insoles and pain medication) or to supervised non-surgical treatment alone. Including quality-adjusted life years (QALYs) data from baseline, 3, 6, 12 and 24 months, effectiveness was measured as change at 24 months. Healthcare costs and transfer payments were derived from national registries. Incremental healthcare costs, and incremental cost-effectiveness ratios (ICERs) were calculated. A probabilistic sensitivity analysis was conducted and the probability of cost-effectiveness was estimated at the 22 665 Euros/QALY threshold defined by the National Institute for Health and Care Excellence.

RESULTS

TKR plus non-surgical treatment was more expensive (mean of 23 076 vs 14 514 Euros) but also more effective than non-surgical treatment (mean 24-month improvement in QALY of 0.195 vs 0.056). While cost-effective in the unadjusted scenario (ICER of 18 497 Euros/QALY), TKR plus non-surgical treatment was not cost-effective compared with non-surgical treatment with the option of later TKR if needed in the adjusted (age, sex and baseline values), base-case scenario (ICER of 32 611 Euros/QALY) with a probability of cost-effectiveness of 23.2%. Including deaths, TKR plus non-surgical treatment was still not cost-effective (ICERs of 46 277 to 64 208 Euros/QALY).

CONCLUSIONS

From a 24-month perspective, TKR plus non-surgical treatment does not appear to be cost-effective compared with non-surgical treatment with the option of later TKR if needed in patients with moderate-to-severe knee osteoarthritis and moderate intensity pain in secondary care in Denmark. Results were sensitive to changes, highlighting the need for further confirmatory research also assessing the long-term cost-effectiveness of TKR.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT01410409).

Cost-Effectiveness of Treating Early to Moderate Stage Knee Osteoarthritis with Intra-articular Hyaluronic Acid Compared to Conservative Interventions

INTRODUCTION

Evidence has demonstrated greater benefit of intra-articular hyaluronic acid (IA-HA) within earlier stages of knee osteoarthritis (OA) rather than waiting for patients to have progressed to later stages of disease progression. High molecular weight (HMW) HA has also been shown to be more effective than low molecular weight (LMW) HA products in mild to moderate knee OA, providing an important distinction to make within the class of IA-HA therapies. The purpose of this study is to evaluate the cost-effectiveness of treating patients with knee OA with HMW HA compared to LMW and conservative treatment, while taking into account disease stage.

METHODS

Decision analytic models were created for early/moderate, as well as late stage knee OA. Models for late stage knee OA were created by assuming a range of response rates to IA-HA treatments from 10% to 50%. These models included conservative treatment using physical therapy/exercise, braces/orthosis, and medications such as non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics. The models compared the cost per quality adjusted life year (QALY) gained for these treatments to the use of either LMW or HMW HA. Incremental cost-effectiveness ratios (ICERs) were calculated for each treatment in relation to HMW HA.

RESULTS

When evaluating treatment in early to moderate knee OA, HMW HA was dominant over LMW HA and physical therapy/exercise, as it was less expensive and provided greater benefit. HMW HA was cost-effective versus braces/orthosis and NSAID/analgesic medications based on a willingness to pay threshold of $50,000. In the model of 50% response rate to IA-HA for late stage OA, HMW HA remained cost-effective in comparison to physical therapy/exercise and braces/orthosis at a willingness to pay threshold of $50,000; but not NSAID/analgesic medications. In the worst-case scenario of a 10% responder rate to IA-HA, HMW HA was no longer cost-effective in any circumstance.

CONCLUSION

IA-HA, particularly HMW formulations, demonstrate cost-effectiveness when compared to conservative treatment options and LMW HA in patients with early/mid stage knee OA. The cost-effectiveness of HMW HA in patients with later stage knee OA was not as apparent, particularly because of the uncertainty in the proportion of patients with late stage OA who have a meaningful improvement after receiving IA-HA. This cost-effectiveness finding supports the use of IA-HA in patients with early and moderate knee OA, as the benefits of IA-HA are apparent within the patient population with mild to moderate knee OA. The findings of this study suggest that there is a potential cost savings benefit as a result of utilizing HMW HA in earlier stages of knee OA as opposed to later stages.

FUNDING

Ferring Pharmaceuticals Inc.

Three-dimensional printed porous tantalum prosthesis for treating inflammation after total knee arthroplasty in one-stage surgery - a case report

Chronic inflammation and bone defects after total knee arthroplasty are a challenge for the orthopedic surgeon. There have been few reports on application of a three-dimensional (3D) printed porous tantalum prosthesis in such situations. We report an 83-year-old female patient who presented to our clinic with consistent pain of the left knee for 10 years and a severe decline in mobility for 2 years. Chronic inflammation, loosening of a tibial prosthesis with a bone defect, and severe osteoporosis were diagnosed. The patient was treated with computer designed and manufactured, personalized, 3D printed porous pure tantalum pad-assisted left total knee arthroplasty. The surgery went smoothly and the patient achieved a satisfactory recovery after surgery. A 3D printed porous tantalum prosthesis can be used to reconstruct tibial bone defects in patients with chronic inflammation after joint replacement surgeries.

Effectiveness of continuous versus pulsed short-wave diathermy in the management of knee osteoarthritis: A randomized pilot study

Background:

Short-wave diathermy (SWD) is an electrotherapeutic modality used in the conservative treatment of knee osteoarthritis (KOA). Electromagnetic radiation delivered in continuous (cSWD) or pulse (pSWD) mode provides a deep heating effect on tissues. There is no consensus on outcomes of treatment with cSWD versus pSWD in KOA. The aim of this study was to compare the effects of cSWD versus pSWD on pain, functionality and walking distance in KOA.

Methods:

34 female patients aged 49-65 with KOA were randomized into two groups. A total of 27 patients completed the study. One group (n=11) was treated with cSWD, the other (n=16) with pSWD for three weeks. Patients were assessed before, after and at one month post therapy. Outcome measures included visual analogue scale (VAS) for knee pain, Western Ontario and Mcmaster University Osteoarthritis Index (WOMAC) and a six-minute walking test (6MWT).

Results:

Based on the minimal clinically important improvement (MCII), there was a reduction in VAS and WOMAC scores in both cSWD and pSWD groups post treatment (-37.3mm, 31.2mm respectively for VAS and 26%, 23% respectively for WOMAC) and at one month post treatment. There was no difference in pre and post treatment VAS for pain, WOMAC or 6MWT scores between the two groups. There was a small post treatment effect size on between- group 6MWT scores (Cohen’s d: 0.238).

Conclusion:

Both treatment options appear to be efficacious in reducing pain and improving functionality in KOA. There was no between-group difference. A larger study must be conducted to consolidate these findings.

A Cost-Effectiveness Analysis of Isolated Meniscal Repair Versus Partial Meniscectomy for Red-Red Zone, Vertical Meniscal Tears in the Young Adult

PURPOSE

To evaluate the cost-effectiveness of treating isolated red-red zone, vertical meniscal tears with either isolated meniscal repair (IMR) or partial meniscectomy (PM) in the young adult using conservative modeling.

METHODS

A decision-analytic Markov disease progression model with a 40-year horizon was created simulating outcomes after IMR or PM for an isolated meniscal tear. Event probabilities, costs, and utilities were used for the index procedures, and the development of osteoarthritis (OA) and subsequent need for knee arthroplasty were calculated or selected from the published literature. Differences in cost, difference in quality-adjusted life years (QALYs), and the incremental cost effect ratio were calculated to determine which index procedure is most cost effective.

RESULTS

Total direct costs from PM were modeled at $38,648, and the total direct costs of IMR were $23,948, resulting in a projected cost savings of $14,700 with IMR. There was a modeled gain in QALYs of 17 for PM and 21 for IMR, resulting in an increase in 4 QALYs for the IMR treatment group. This results in an incremental cost effect ratio of $3,935 per QALY, favoring IMR as the dominant procedure.

CONCLUSIONS

Meniscal repair for isolated red-red zone, vertical meniscal tears was predicted to have lower direct costs and improve QALYs compared with partial meniscectomy over 40-year modeling, indicating isolated meniscal repair to be the cost-effective procedure in the treatment of an isolated meniscal tear in the young adult population.

LEVEL OF EVIDENCE

Level 3: economic and decision analysis.

Biomaterial-engineered intra-articular drug delivery systems for osteoarthritis therapy

Osteoarthritis (OA) is a progressive and degenerative disease, which is no longer confined to the elderly. So far, current treatments are limited to symptom relief, and no valid OA disease-modifying drugs are available. Additionally, OA relative joint is challenging for drug delivery, since the drugs experience rapid clearance in joint, showing a poor bioavailability. Existing therapeutic drugs, like non-steroidal anti-inflammatory drugs (NSAIDs) and corticosteroids, are not conducive for long-term use due to adverse effects. Though supplementations, including chondroitin sulfate and glucosamine, have shown beneficial effects on joint tissues in OA, their therapeutic use is still debatable. New emerging agents, like Kartogenin (KGN) and Interleukin-1 receptor antagonist (IL-1 ra), without a proper formulation, still will not work. Therefore, it is urgent to establish a suitable and efficient drug delivery system for OA therapy. In this review, we pay attention to various types of drug delivery systems and potential therapeutic drugs that may escalate OA treatments.

Body-Self Unity With a New Hip or Knee: Understanding Total Joint Replacement Within an Embodiment Framework

Medical research increasingly makes use of embodiment concepts to understand how illness disrupts unity of body and self. However, few have applied embodiment concepts in total joint replacement (TJR), an effective treatment for end‐stage arthritis. In considering why a troubling proportion of TJR recipients have continued pain and functional limitation, we ask: what role might be played by the embodied experience of living with an implant? Relevant theoretical models and prior research on embodiment in musculoskeletal health and transplantation are reviewed. Our findings suggest a research agenda with implications for addressing suboptimal outcomes in TJR.

Ninety-day and one-year healthcare utilization and costs after knee arthroplasty

OBJECTIVES

This study examined ninety-day and one-year postoperative healthcare utilization and costs following total knee arthroplasty (TKA) from the health sector and patient perspectives.

DESIGN

This study relied on: 1) patient-reported medical resource utilization data from diaries in the Knee Arthroplasty Pain Coping Skills Training (KASTPain) trial; and 2) Medicare fee schedules. Medicare payments, patient cost-sharing, and patient time costs were estimated. Generalized linear mixed models were used to identify baseline predictors of costs.

RESULTS

In the first ninety days following TKA, patients had an average of 29.7 outpatient visits and 6% were hospitalized. Mean total costs during this period summed to $3,720, the majority attributed to outpatient visit costs (84%). Over the year following TKA, patients had an average of 48.9 outpatient visits, including 33.2 for physical therapy. About a quarter (24%) of patients were hospitalized. Medical costs were incurred at a decreasing rate, from $2,428 in the first six weeks to $648 in the last six weeks. Mean total medical costs across all patients over the year were $8,930, including $5,328 in outpatient costs. Total costs were positively associated with baseline Charlson comorbidity score (P < 0.01). Outpatient costs were positively associated with baseline Charlson comorbidity score (P = 0.03) and a bodily pain burden summary score (P < 0.01). Mean patient cost-sharing summed to $1,342 and time costs summed to $1,346.

CONCLUSIONS

Costs in the ninety days and year after TKA can be substantial for both healthcare payers and patients. These costs should be considered as payers continue to explore alternative payment models.

Surgical and tissue engineering strategies for articular cartilage and meniscus repair

Injuries to articular cartilage and menisci can lead to cartilage degeneration that ultimately results in arthritis. Different forms of arthritis affect ~50 million people in the USA alone, and it is therefore crucial to identify methods that will halt or slow the progression to arthritis, starting with the initiating events of cartilage and meniscus defects. The surgical approaches in current use have a limited capacity for tissue regeneration and yield only short-term relief of symptoms. Tissue engineering approaches are emerging as alternatives to current surgical methods for cartilage and meniscus repair. Several cell-based and tissue-engineered products are currently in clinical trials for cartilage lesions and meniscal tears, opening new avenues for cartilage and meniscus regeneration. This Review provides a summary of surgical techniques, including tissue-engineered products, that are currently in clinical use, as well as a discussion of state-of-the-art tissue engineering strategies and technologies that are being developed for use in articular cartilage and meniscus repair and regeneration. The obstacles to clinical translation of these strategies are also included to inform the development of innovative tissue engineering approaches.

Comparative Effectiveness of Alternative Dosing Regimens of Hyaluronic Acid Injections for Knee Osteoarthritis: A Systematic Review

CONTEXT

Viscosupplementation is widely used for management of knee osteoarthritis. Many formulations of hyaluronic acid (HA) are available, ranging from a single injection to a series of up to 5 injections per treatment.

OBJECTIVE

To compare efficacy between single and multiple HA injection formulations.

DATA SOURCES

MEDLINE, EMBASE, Cochrane, Web of Science, Scopus databases were all searched.

STUDY SELECTION

Full-text prospective randomized and nonrandomized controlled human trials, cohort studies, and cost-effectiveness evaluations in the English language comparing different injection regimens of viscosupplementation were included.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 1.

DATA EXTRACTION

Data were collected using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Four databases were searched by a librarian and the principal investigator, identifying 6196 articles for screening.

RESULTS

Eleven studies met the inclusion criteria. Of the studies comparing single- with multiple-injection formulations of HA for treatment of knee osteoarthritis, there was no consistent difference in patient-reported outcomes. Furthermore, 5-injection formulations do not appear to be superior to 3-injection formulations.

CONCLUSION

There are limited head-to-head trials comparing viscosupplementation formulations that differ based on number of injections, and in particular, there is a paucity of trials evaluating single-injection formulations. Based on the currently available data, there appears to be similar efficacy with the possibility for greater cost-effectiveness and less patient inconvenience with single-injection formulations.

Effect of Deep Slow Breathing on Pain-Related Variables in Osteoarthritis

This study evaluated the effect of a six-week deep slow breathing (DSB) program on pain, physical function, and heart rate variability (HRV) in subjects with lower extremity joint pain. Twenty subjects were assigned into training (n = 10) and control (n = 10) groups. The training group participated in a six-week DSB program consisting of weekly training sessions and at-home breathing exercises. DSB exercises focused on prolonging the exhalation and the pause following exhalation. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to assess pain and physical function, and HRV data were obtained before and after intervention. Results revealed no significant interactions between group and time for any of the variables. There was no significant main effect for group, but there was a significant main effect (p < 0.025) and a large effect size for time on both pain (η _p ² = 0.454) and physical function (η _p ² = 0.506). There were no significant main effects (p > 0.017) for group and time on LF power (group η _p ² = 0.039, time η _p ² = 0.061), HF power (group η _p ² = 0.039, time η _p ² = 0.039), and LF/HF ratio (group η _p ² = 0.036, time η _p ² = 0.169). Results indicated that the six-week DSB program was not sufficient to alleviate pain or improve physical function in subjects with lower extremity joint pain. Although the pain was not alleviated, other beneficial effects such as better coping with the pain were reported in the majority of training subjects. As this is the first study to examine the use of DSB for lower extremity joint pain and dysfunction, further research is needed to investigate the efficacy and applicability of DSB.

Effects of Osteoarthritis Pain and Concurrent Insomnia and Depression on Health Care Use in a Primary Care Population of Older Adults

OBJECTIVE

To examine independent and combined effects of pain with concurrent insomnia and depression symptoms on the use of health care services in older adults with osteoarthritis (OA).

METHODS

Patients were Group Health Cooperative (GHC) patients with a primary diagnosis of OA (n = 2,976). We used survey data on pain (Graded Chronic Pain Scale), insomnia (Insomnia Severity Index), and depression (Patient Health Questionnaire-8), and health care use extracted from GHC electronic health records (office visits, length of stay, outpatient and inpatient costs, and hip or knee replacement) for 3 years after the survey. Negative binomial, logistic, and generalized linear models were used to assess predictors of health care use.

RESULTS

Approximately 34% and 29% of patients displayed at least subclinical insomnia and at least subclinical depression symptoms, respectively, in addition to moderate-to-severe pain. Pain had the greatest independent effects on increasing all types of health care use, followed by depression (moderate effects) on increased office visits, length of stay, outpatient and inpatient costs, and insomnia (mild effects) on decreased length of stay. No synergistic effects of the 3 symptoms on use of health care services were observed. The combined effects of pain plus insomnia and pain plus depression were significant for all types of health care use and increased greatly with increasing severity of insomnia and depression, except for hip/knee replacement.

CONCLUSION

Pain is the main driver for health care use in patients with OA. In addition to pain, insomnia plus depression jointly increased diverse types of health care use, and these combined effects increased greatly with increasing severity of insomnia and depression. These findings indicate the important role that concurrent symptomatic conditions may play in increasing use of health care services.

Sex differences in negative affect and postoperative pain in patients undergoing total knee arthroplasty

Background

Knee osteoarthritis (OA) is among the most common and disabling persistent pain conditions, with increasing prevalence in the developed world, and affects women to a greater degree than men. In the USA, the growth of knee OA has been paralleled by an increase in rates of total knee arthroplasty (TKA), a surgical treatment option for late-stage knee OA. While TKA outcomes are generally good, postoperative trajectories of pain vary widely, with some patients reporting a complete absence of pain, but with a significant minority reporting worsening pain. Biopsychosocial factors, including anxiety and depression, are known to contribute importantly to the experience of joint pain, with women reporting a higher degree of negative affective symptoms.

Methods

This study investigated sex differences in TKA outcomes in age-matched groups of men and women at two academic medical centers. Pain and physical function were assessed in 100 patients (50 men and 50 women) during the perioperative period (preoperative visit—6 weeks postsurgical). The association of preoperative negative affect (anxiety and depression scores) to postoperative pain and function was evaluated, with specific attention to sex differences in this relationship.

Results

Overall, women reported more baseline pain-related physical dysfunction (although not higher baseline pain scores), as well as higher acute postoperative pain scores during the 2 weeks following TKA than their male counterparts. By 6 weeks postoperatively, sex differences in reported pain were no longer evident. Interestingly, although women reported higher preoperative levels of emotional distress than men, preoperative anxiety and depression scores were better predictors of severe postoperative pain among men than women, throughout the postoperative test period.

Conclusions

This study underlines the importance of considering sex and psychosocial factors, as well as their interaction, in understanding postsurgical pain trajectories.

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.

Interaction between GDF5 gene polymorphisms and environment factors increased the risk of knee osteoarthritis: a case-control study

Using a case–control design, we assessed the association between single nucleotide polymorphisms (SNPs) of growth and differentiation factor 5 (GDF5)/rs143383 gene and interaction with environments and knee osteoarthritis (KOA). We recruited 288 KOA patients from the First Clinical College, Henan University of Chinese Medicine between June 2017 and May 2018. There was significant difference in genotype distribution between case group and control group (χ² = 22.661, P=0.000). The minor C allele was significantly higher in the case group than that in the control group (20.5 vs 8.1%, P=0.000, odds ratio (OR) = 1.62, 95% confidence interval (CI): 1.29–2.03). Significant differences were also observed in other gene models. For age, all models show significant differences (P<0.05) for those whose age was more than 60 years, and no significant difference was observed for those under 60 years. For non-smoking group, there were significant differences between case group and control group, and for smoker, significance level was found in TT compared with CC and allele gene models. Patients with drinking and Bbody mass index (MI )≥ 24 also showed significant relationship between rs143383 and osteoarthritis (OA) under the following models: TT vs CC (P=0.000, P=0.018), TT/CT vs CC (P=0.043), TT vs CT/CC (P=0.000, P=0.009), and T vs C (P=0.024, P=0.000). Other gene models indicated no significance (P>0.05). Our results revealed a possible genetic association between GDF5 and KOA, and the TT genotype of rs143383 increased the risk of KOA in Chinese Han population. The interaction between GDF5 gene and drinking, smoking, and obesity further increased the risk of KOA.

Functional Status in Knee Osteoarthritis and its Relation to Demographic and Clinical Features

Objectives:

To assess the functional status in a cohort of Iraqi patients with knee Osteoarthritis (OA) and its relation to demographic and clinical features.

Patients and methods:

This cross-sectional study was conducted on 150 patients with knee OA diagnosed according to the American College of Rheumatology Criteria for classification knee OA. Patients’ age, gender, body mass index (BMI), smoking history, educational level, and disease duration were recorded. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score was used to measure functional status of patients with knee OA.

Results:

A total of 150 (97 females) patients with knee OA were recruited in the study. The mean age of patients was 52.5±10.1 year and mean BMI was 30.3±6.0 kg/m². The mean of total WOMAC score was 8.05±2.10 (Range 3–12). The mean WOMAC of: pain score was 3.22 ±0.76 (1-4), stiffness score was 2.05±1.01 and for functional disability score was 2.79±0.88. There was a positive significant correlation between age of the patients and severity of knee OA assessed with total WOMAC score (p=0.026). However, there was a significant negative correlation between educational level and total WOMAC score (p=0.015).

Conclusions:

Functional status in knee OA was impaired and there was a statistically positive significant correlation between age of the patients and severity of knee OA with functional impairment. Also, significant negative correlation was demonstrated between educational level and functional impairment.

The TeMPO trial (treatment of meniscal tears in osteoarthritis): rationale and design features for a four arm randomized controlled clinical trial

BACKGROUND

Meniscal tears often accompany knee osteoarthritis, a disabling condition affecting 14 million individuals in the United States. While several randomized controlled trials have compared physical therapy to surgery for individuals with knee pain, meniscal tear, and osteoarthritic changes (determined via radiographs or magnetic resonance imaging), no trial has evaluated the efficacy of physical therapy alone in these subjects.

METHODS

The Treatment of Meniscal Tear in Osteoarthritis (TeMPO) Trial is a four-arm multi-center randomized controlled clinical trial designed to establish the comparative efficacy of two in-clinic physical therapy interventions (one focused on strengthening and one containing placebo) and two protocolized home exercise programs.

DISCUSSION

The goal of this paper is to present the rationale behind TeMPO and describe the study design and implementation strategies, focusing on methodologic and clinical challenges.

TRIAL REGISTRATION

The TeMPO Trial was first registered at clinicaltrials.gov with registration No. NCT03059004 . on February 14, 2017.

Cost-effectiveness of health coaching and financial incentives to promote physical activity after total knee replacement

OBJECTIVE

We evaluated the cost-effectiveness of Telephonic Health Coaching and Financial Incentives (THC + FI) to promote physical activity in total knee replacement recipients.

DESIGN

We used the Osteoarthritis Policy Model, a computer simulation of knee osteoarthritis, to evaluate the cost-effectiveness of THC + FI compared to usual care. We derived transition probabilities, utilities, and costs from trial data. We conducted lifetime analyses from the healthcare perspective and discounted all cost-effectiveness outcomes by 3% annually. The primary outcome was the Incremental Cost-Effectiveness Ratio (ICER), defined as the ratio of the differences in costs and Quality-Adjusted Life Years (QALYs) between strategies. We considered ICERs <$100,000/QALY to be cost-effective. We conducted one-way sensitivity analyses that varied parameters across their 95% confidence intervals (CI) and limited the efficacy of THC + FI to 1 year or to 9 months. We also conducted a probabilistic sensitivity analysis (PSA), simultaneously varying cost, utilities, and transition probabilities.

RESULTS

THC + FI had an ICER of $57,200/QALY in the base case and an ICER below $100,000/QALY in most deterministic sensitivity analyses. THC + FI cost-effectiveness depended on assumptions about long-term efficacy; when efficacy was limited to 1 year or to 9 months, the ICER was $93,300/QALY or $121,800/QALY, respectively. In the PSA, THC + FI had an ICER below $100,000/QALY in 70% of iterations.

CONCLUSIONS

Based on currently available information, THC + FI might be a cost-effective alternative to usual care. However, the uncertainty surrounding this choice is considerable, and further research to reduce this uncertainty may be economically justified.