Knee osteoarthritis and adverse health outcomes: an umbrella review of meta-analyses of observational studies

Efficacy and Safety of Stem Cell Therapy for Orthopedic Conditions, Including Osteoarthritis and Bone Defects

INTRODUCTION

Orthopedic conditions like osteoarthritis and bone defects pose significant challenges due to their impact on individuals' quality of life. Traditional treatments often provide only symptomatic relief, necessitating alternative therapies for long-term management. Stem cell therapy has grabbed attention for its regenerative and immunomodulatory properties, offering potential for tissue repair and functional restoration.

OBJECTIVE

This study aims to assess the efficacy and safety of stem cell therapy for orthopedic conditions, specifically osteoarthritis and bone defects.

MATERIALS AND METHODS

A retrospective cross-sectional study analyzed data from patients who underwent stem cell therapy for osteoarthritis or bone defects between January and September 2023. Outcome measures focused on pain and function improvements using tools such as Visual Analog Scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), alongside radiographic assessments. Adverse events, range of motion, quality of life, and demographic factors were also examined. Data were collected from electronic medical records while maintaining patient confidentiality. Descriptive statistics using SPSS (IBM Corp., Armonk, NY, USA) were employed to analyze patient characteristics, treatment variables, and outcomes, with statistical significance determined using Chi-square test and Independent t-test.

RESULTS

Out of 50 individuals, the majority, i.e., 35 (or 70%), were diagnosed with osteoarthritis, while the remaining 15 (30%) had bone defects. Treatment outcomes showed significant improvements in pain and function, with a decrease in mean VAS and WOMAC scores at the six-month follow-up. Seven participants (28%) reported adverse events, and two participants (8%) experienced serious adverse events.

CONCLUSION

Stem cell therapy shows promise for treating orthopedic conditions like osteoarthritis and bone defects. While demonstrating efficacy in pain management and functional improvement, safety considerations warrant further investigation and optimization of treatment protocols. Future research should focus on refining stem cell therapy techniques and addressing safety concerns to maximize its therapeutic potential in orthopedic practice.

Prevalence and Clinical Impact of Sarcopenia in Patients Undergoing Total Joint Arthroplasty: A Systematic Review and a Meta-Analysis

BACKGROUND

Sarcopenia is a progressive loss of skeletal muscle mass and function. It is associated with adverse outcomes after several orthopaedic procedures. However, its role in total joint arthroplasty (TJA) is not fully explored. Therefore, we wanted to conduct a systematic review and meta-analysis to answer the following questions: (1) What is the prevalence of sarcopenia in patients undergoing TJA?; (2) What factors are associated with the prevalence of sarcopenia in patients undergoing TJA?; What is the impact of sarcopenia on medical outcomes following TJA?; and (4) What is the impact of sarcopenia on surgical outcomes following TJA?

METHODS

Electronic databases PubMed, Scopus, Cochrane, and Google Scholar were searched. The data were pooled using the random-effects model and graphically represented by a forest plot. We included a total of 13 studies, evaluating 399,097 patients.

RESULTS

The pooled prevalence of sarcopenia was 20.1% (95% confidence interval [CI] 13.6 to 28.8%; P < .00001; I2 = 94.7%) in total knee arthroplasty (TKA) and 5.2% (95% CI 0.1 to 69.7%; P = .128; I2 = 99.6%) in total hip arthroplasty (THA). Meta-regression found no links between age, sex, body mass index, diabetes, obesity, arthroplasty type, and sarcopenia prevalence in TJA. Sarcopenia increased risk of blood transfusion (odds ratio [OR] 4.68 [95% CI 3.51 to 6.25]; P < .00001), pneumonia (OR 1.94 [95% CI 1.14 to 3.30]; P = .01), urinary tract infection (UTI) (OR 1.64 [95% CI 1.31 to 2.05]; P < .001), prosthetic fracture (OR 2.12 [95% CI 1.51 to 2.98]; P < .0001), prosthetic dislocation (OR 1.99 [95% CI 1.62 to 2.44]; P < .00001), and mechanical loosening (OR 1.78 [95% CI 1.43 to 2.22]; P < .00001) in TKA. Sarcopenic patients were at an increased risk of UTI (OR 1.79 [95% CI 1.32 to 2.43]; P = .0002) and prosthetic loosening (OR 1.97 [95% CI 1.10 to 3.53]; P = .02) post-THA.

CONCLUSIONS

Baseline sarcopenia was prevalent in patients undergoing TJA. It was associated with an increased risk of UTI and prosthetic loosening following TKA and THA. Increased risk of blood transfusion, pneumonia, prosthetic fractures, and mechanical loosening following TKA.

[Relationship between hypercholesterolemia and osteoarthritis (preliminary results)]

AIM

To evaluate the relationship of hypercholesterolemia (HCE) with clinical, instrumental, and laboratory parameters in osteoarthritis (OA) in a multicenter, cross-sectional study.

MATERIALS AND METHODS

The study included 183 patients aged 40-75 years, with a confirmed diagnosis of stage I-III OA (ACR) of the knee joints, who signed an informed consent. The mean age was 55.6±10.7 years (40 to 75), body mass index was 29.3±6.3 kg/m2, and disease duration was 5 [1; 10] years. For each patient, a case record form was filled out, including anthropometric indicators, medical history, clinical examination data, an assessment of knee joint pain according to VAS, WOMAC, KOOS and comorbidities. All patients underwent standard radiography and ultrasound examination of the knee joints and laboratory tests.

RESULTS

HCE was detected in 59% of patients. Depending on its presence or absence, patients were divided into two groups. Patients were comparable in body mass index, waist and hip measurement, and disease duration but differed significantly in age. Individuals with elevated total cholesterol levels had higher VAS pain scores, total WOMAC and its components, an overall assessment of the patient's health, a worse KOOS index, and ultrasound findings (reduced cartilage tissue). HCE patients showed high levels of cholesterol, low-density lipoproteins, triglycerides, STX-II, and COMP (p<0.05). However, after stratification by age, many initial intergroup differences became insignificant, and differences in the WOMAC pain score persisted.

CONCLUSION

The results of the study confirmed the high prevalence of HCE in OA patients (59%). Patients with OA and increased total cholesterol have more intense pain in the knee joints.

Exosomes derived from miR-146a-overexpressing fibroblast-like synoviocytes in cartilage degradation and macrophage M1 polarization: a novel protective agent for osteoarthritis?

Introduction

Pathological changes in the articular cartilage (AC) and synovium are major manifestations of osteoarthritis (OA) and are strongly associated with pain and functional limitations. Exosome-derived microRNAs (miRNAs) are crucial regulatory factors in intercellular communication and can influence the progression of OA by participating in the degradation of chondrocytes and the phenotypic transformation in the polarization of synovial macrophages. However, the specific relationships and pathways of action of exosomal miRNAs in the pathological progression of OA in both cartilage and synovium remain unclear.

Methods

This study evaluates the effects of fibroblast-like synoviocyte (FLS)-derived exosomes (FLS-Exos), influenced by miR-146a, on AC degradation and synovial macrophage polarization. We investigated the targeted relationship between miR-146a and TRAF6, both in vivo and in vitro, along with the involvement of the NF-κB signaling pathway.

Results

The expression of miR-146a in the synovial exosomes of OA rats was significantly higher than in healthy rats. In vitro, the upregulation of miR-146a reduced chondrocyte apoptosis, whereas its downregulation had the opposite effect. In vivo, exosomes derived from miR-146a-overexpressing FLSs (miR-146a-FLS-Exos) reduced AC injury and chondrocyte apoptosis in OA. Furthermore, synovial proliferation was reduced, and the polarization of synovial macrophages shifted from M1 to M2. Mechanistically, the expression of TRAF6 was inhibited by targeting miR-146a, thereby modulating the Toll-like receptor 4/TRAF6/NF-κB pathway in the innate immune response.

Discussion

These findings suggest that miR-146a, mediated through FLS-Exos, may alleviate OA progression by modulating cartilage degradation and macrophage polarization, implicating the NF-κB pathway in the innate immune response. These insights highlight the therapeutic potential of miR-146a as a protective agent in OA, underscoring the importance of exosomal miRNAs in the pathogenesis and potential treatment of the disease.

Rehabilitation Applications Based on Behavioral Therapy for People With Knee Osteoarthritis: Systematic Review

BACKGROUND

The development of digital applications based on behavioral therapies to support patients with knee osteoarthritis (KOA) has attracted increasing attention in the field of rehabilitation. This paper presents a systematic review of research on digital applications based on behavioral therapies for people with KOA.

OBJECTIVE

This review aims to describe the characteristics of relevant digital applications, with a special focus on the current state of behavioral therapies, digital interaction technologies, and user participation in design. The secondary aim is to summarize intervention outcomes and user evaluations of digital applications.

METHODS

A systematic literature search was conducted using the keywords "Knee Osteoarthritis," "Behavior Therapy," and "Digitization" in the following databases (from January 2013 to July 2023): Web of Science, Embase, Science Direct, Ovid, and PubMed. The Mixed Methods Assessment Tool (MMAT) was used to assess the quality of evidence. Two researchers independently screened and extracted the data.

RESULTS

A total of 36 studies met the inclusion criteria and were further analyzed. Behavioral change techniques (BCTs) and cognitive behavioral therapy (CBT) were frequently combined when developing digital applications. The most prevalent areas were goals and planning (n=31) and repetition and substitution (n=27), which were frequently used to develop physical activity (PA) goals and adherence. The most prevalent combination strategy was app/website plus SMS text message/telephone/email (n=12), which has tremendous potential. This area of application design offers notable advantages, primarily manifesting in pain mitigation (n=24), reduction of physical dysfunction (n=21), and augmentation of PA levels (n=12). Additionally, when formulating design strategies, it is imperative to consider the perspectives of stakeholders, especially in response to the identified shortcomings in application design elucidated within the study.

CONCLUSIONS

The results demonstrate that "goals and planning" and "repetition and substitution" are frequently used to develop PA goals and PA behavior adherence. The most prevalent combination strategy was app/website plus SMS text message/telephone/email, which has tremendous potential. Moreover, incorporating several stakeholders in the design and development stages might enhance user experience, considering the distinct variations in their requirements. To improve the efficacy and availability of digital applications, we have several proposals. First, comprehensive care for patients should be ensured by integrating multiple behavioral therapies that encompass various aspects of the rehabilitation process, such as rehabilitation exercises and status monitoring. Second, therapists could benefit from more precise recommendations by incorporating additional intelligent algorithms to analyze patient data. Third, the implementation scope should be expanded from the home environment to a broader social community rehabilitation setting.

Chronic Pain in the Lower Extremities and Low Back is Associated With Recurrent Falls in Community-Dwelling Japanese People Aged 40-74 Years

OBJECTIVE

To determine the longitudinal association between chronic pain in the lower extremities and low back and the odds of recurrent falls in middle-aged and older people.

DESIGN

A cohort study.

SETTING

Communities in Japan.

PARTICIPANTS

Participants were 7540 community-dwelling volunteers aged 40-74 years (N=7540). The baseline survey was a self-administered questionnaire conducted between 2011-2013. Predictors were presence of chronic pain in the knee, foot or ankle, and low back, with the degree of pain categorized as none, very mild/mild, moderate, or severe/very severe. Covariates in the multivariate model of chronic pain in a site were demographics, body mass index, physical activity level, disease history, and chronic pain in the other 2 sites. Logistic regression analysis was used to calculate odds ratios (ORs).

INTERVENTIONS

None.

MAIN OUTCOME MEASURE(S)

Recurrent falls in the year before the 5-year follow-up survey.

RESULTS

Mean participant age was 60.2 years. Higher degrees of chronic pain were associated with higher odds of recurrent falls for the knee (P=.0002) with a higher OR of 1.48 (95% CI: 1.11-1.97), for the foot or ankle (P=.0001) with a higher OR of 1.97 (95% CI: 1.36-2.86), and for the low back (P=.0470) with a higher OR of 1.45 (95% CI: 1.09-1.91) in those with any degree of pain relative to those without pain. Higher degrees of chronic knee pain were associated with higher odds of recurrent falls in women (P=.0005), but not in men (P=.0813). Meanwhile, higher degrees of chronic low back pain were associated with the odds of recurrent falls in men (P=.0065), but not in women (P=.8735).

CONCLUSIONS

Chronic pain in the knee, foot or ankle, and lower back was independently and dose-dependently associated with a higher risk of recurrent falls. A marked sex-dependent difference was also noted in the association.

Systemic osteoarthritis: the difficulty of categorically naming a continuous condition

Osteoarthritis (OA) is a disease with systemic implications that go beyond joint problems. Its pathogenic mechanisms involve a variety of systemic conditions that contribute to joint damage. These include metabolic dysfunction, chronic low-grade inflammation, neuroplastic pain, and the influence of the central nervous system in the development of neuropathic pain. Besides, OA can negatively affect other aspects of health, such as quality of life, reduced physical activity, social isolation, depression, and anxiety. OA can be considered a complex system in which pathological interactions involve not only obesity and metabolic dysfunction, but also fragility syndrome, sarcopenia, neurological complications, and systemic energy redistribution. Complex systems are composed of multiple interacting and dynamic parts and exhibit emergent properties that cannot be fully explained by examining their individual components. Chronic low-grade inflammation is characteristic of OA, occurring both in the affected joint, and systemically, mainly due to adipose tissue inflammation in obese patients. Obesity is a key factor in the progression of OA, so primary treatment should focus on its control, while maintaining muscle health. The chronic inflammation could lead to changes in energy distribution among the affected joint tissues. Therefore, OA should be approached as a systemic disease, considering individual patient factors, such as genetics, inflammatory response, and lifestyle. Medical care should be more holistic and personalized. Consideration of a name change, such as "systemic OA", could help to move away from the perception of a disease focused only on the joints.

Personalized Physical Activity Programs for the Management of Knee Osteoarthritis in Individuals with Obesity: A Patient-Centered Approach

Physical activity (PA) plays a vital role in knee osteoarthritis (KOA) management. However, engaging individuals with KOA in regular exercise is challenging, especially when they are affected by obesity. The aim of the current review is to elucidate how to increase adherence to exercise in this population. When implementing a PA program with patients with KOA and obesity, a specific multi-step approach can be adopted. In phase I (the baseline assessment), the patients' eligibility for exercise is ascertained and a physical fitness assessment, sarcopenic obesity screening and quantification of the pain experienced are undertaken. Phase II adopts a patient-centered approach in implementing a PA program that combines an active lifestyle (>6000 steps/day) with land- or water-based exercise programs performed over eight to twelve weeks, with a frequency of three to five sessions per week, each lasting 60 min. In phase III, several strategies can be used to increase the patients' adherence to higher levels of PA, including the following: (i) personalizing PA goal-setting and real-time monitoring; (ii) enhancing physical fitness and the management of sarcopenic obesity; (iii) building a sustainable environment and a supportive social network for an active lifestyle; and (iv) reducing pain, which can ameliorate the clinical severity of KOA and help with weight management in this population.

Perspectives on Aging and Quality of Life

The aging of the world's population and the health problems accompanying it are becoming increasingly severe. Healthcare policies in developed countries focus on how to prevent and treat diseases associated with aging and how to maintain quality of life. Typical age-related diseases include deafness, cataracts, osteoarthritis, chronic obstructive pulmonary disease, diabetes mellitus, and dementia. Although the mechanisms by which these diseases develop differ, they are all caused by the accumulation of molecular and cellular damage over time. In addition, age-related diseases can cause a decline in physical and mental functions and the ability to perform activities of daily living, as well as the loss of roles in society and a sense of fulfillment in life. Therefore, there is a need for treatment and measures to accurately grasp and maintain quality of life. This review aims to introduce areas and representative papers expected to be contributed to the special issue of "Aging and Quality of Life".

Effects of strength training on functional ambulation following knee replacement: a systematic review, meta-analysis, and meta-regression

Strength training is recommended by the American Physical Therapy Association to improve muscle strength, mobility, and balance following knee replacement. Few studies have focused on the direct effects of strength training on functional ambulation, and potential dose-response relationships between strength training parameters and the effect remain unclear. The aim of this systematic review, meta-analysis, and meta-regression was to evaluate the effects of strength training on functional ambulation following knee replacement (KR). We also aimed to explore potential dose-response relationships between strength training parameters and performance in functional ambulation. A systematic literature search of eight online databases was performed on March 12, 2023, for randomized controlled trials evaluating the effects of strength training on functional ambulation by six-minute walk test (6MWT) or timed-up and go test (TUG) after KR. Data were pooled by random-effect meta-analyses and presented as weighted mean difference (WMD). A random-effect meta-regression was performed for four predetermined training parameters, namely, duration (weeks), frequency (sessions per week), volume (time per session), and initial time (after surgery) separately to explore dose-response relationships with WMD. Fourteen trials encompassing 956 participants were included in our study. Meta-analyses showed an improvement in 6MWT performance after strength training (WMD: 32.15, 95% CI 19.44-44.85) and a decrease in time to complete TUG (WMD: - 1.92, 95% CI - 3.43 to - 0.41). Meta-regression revealed a dose-response relationship only between volume and 6MWT, with a decreasing trend (P = 0.019, 95% CI - 1.63 to - 0.20). Increasing trends of improvement in 6MWT and TUG were observed with increasing training duration and frequency. A slight decreasing trend of improvement was observed in 6MWT with postponed initial time, while an opposite trend was observed in TUG. Based on existing studies, moderate-certainty evidence suggests that strength training could increase 6MWT distance, and low-certainty evidence shows that strength training could decrease the time to complete TUG after KR. Meta-regression results only suggested a dose-response relationship between volume and 6MWT with a decreasing trend.Registration: PROSPERO: CRD42022329006.

Dynapenic abdominal obesity and susceptibility to fall: a prospective analysis of the Osteoarthritis Initiative

Background

The prediction of the risk of falling remains a challenge in geriatric medicine and the identification of new potential reversible risk factors is a public health priority. In this study, we aim to investigate the association between DAO (dynapenic abdominal obesity) and incident falls in a large sample of people with knee OA (osteoarthritis) or at high risk for this condition, over 8 years of follow-up.

Methods

DAO was defined using a waist circumference more than 102 cm in men and 88 cm in women and a concomitant presence of dynapenia, defined as a time over 15 s in the five times chair stands time. Falls, during follow-up, were recorded using self-reported information in the previous year. A logistic binary regression analysis was run, adjusted for potential confounders at the baseline, reporting the data as odds ratios (ORs) with their 95% confidence intervals (CIs).

Results

Overall, 3,844 subjects were included, majority of whom had abdominal obesity. Across the 8 years of follow-up, 2,695 participants fell vs. 1,149 not reporting any fall. Taking those without DAO as reference, the presence of only dynapenia was not associated with risk of falls (OR = 1.18;95%CI: 0.73-1.91; p = 0.50), whilst the presence of abdominal obesity (OR = 1.30; 95%CI: 1.09-1.56; p = 0.004) and DAO (OR = 1.31; 95%CI:1.01-1.73; p = 0.04) were significantly associated with a higher risk of incident falls.

Conclusion

DAO significantly increased risk of falls as well as the presence of abdominal obesity.

[Electroacupuncture improves motor function of rats with osteoarthritis by alleviating joint inflammation through the Wnt-7B/β-catenin signaling pathway]

OBJECTIVE

To investigate the effect of electroacupuncture on osteoarthritis in rats and explore the possible mechanism.

METHODS

Thirty SD rats were randomly divided into osteoarthritis model group, electro-acupuncture group and control group (n=10), and in the former two groups, early osteoarthritis was induced using a modified DMM surgical modeling method. After successful modeling, the rats in the electro-acupuncture group were treated with electro-acupuncture at bilateral "Housanli" and "Anterior knee point". Behavioral tests of the rats were performed and scored using the LequesneMG scale. Subchondral bone degeneration was observed in each group, and serum levels of IL-1β, ADAMTS-7, MMP-3 and COMP were measured using ELISA. The mRNA and protein expressions of IL-1β, Wnt-7B, β-catenin, ADAMTS-7, and MMP-3 in the cartilage tissue of the knee joints were detected using RT-PCR and Western blotting.

RESULTS

In behavioral tests, the rats in the model and electroacupuncture groups had significantly higher LequesneMG scores after modeling than those in the control group (P < 0.05). After 20 days of treatment, LequesneMG scores were significantly lowered in rats in the electroacupuncture as compared with the model rats (P < 0.05). Imaging examination revealed obvious subchondral bone damage in both the electroacupuncture group and the model group, but the damages were significantly milder with former group. Compared with the model rats, the rats receiving electroacupuncture had significantly lower serum levels of IL-1β, ADAMTS-7, MMP-3 and COMP (P < 0.05) with also lower expressions of IL-1β, Wnt-7B, β-catenin, ADAMTS-7 and MMP-3 in the cartilage tissues at both the mRNA and protein levels (P < 0.05).

CONCLUSION

Electroacupuncture can alleviate joint pain and improve subchondral bone damage in rats with osteoarthritis by reducing IL-1β levels in the joint cartilage tissue and serum to alleviate joint inflammation and by reducing such cytokines as ADAMTS-7 and MMP-3 via regulating the Wnt-7B/β-catenin signaling pathway.

Prevalence of Sarcopenia in Knee Osteoarthritis: A Systematic Review and Meta-Analysis

An association between knee osteoarthritis (OA) and sarcopenia has been proposed, but the evidence is controversial, with the recent literature showing disparate results. Therefore, we aimed to perform a systematic review and meta-analysis to evaluate the prevalence of sarcopenia in knee OA patients compared to people not affected by this condition. We searched several databases until 22 February 2022. The data regarding prevalence were summarized using odds ratios (ORs) with their 95% confidence intervals (CIs). Among the 504 papers initially screened, 4 were included for a total of 7495 participants with a mean age of 68.4 years, who were mainly females (72.4%). The prevalence of sarcopenia in people with knee OA was 45.2%, whilst, in the controls, it was 31.2%. Pooling the data of the studies included that the prevalence of sarcopenia in knee OA was more than two times higher than in the control group (OR = 2.07; 95%CI: 1.43-3.00; I² = 85%). This outcome did not suffer any publication bias. However, after removing an outlier study, the recalculated OR was 1.88. In conclusion, the presence of sarcopenia in knee OA patients was high, affecting one person in every two persons and was higher than in the control groups included.