Risk factors for progression of knee osteoarthritis

Primed IFN-γ-Umbilical Cord Stem Cells Ameliorate Temporomandibular Joint Osteoarthritis

Temporomandibular joint osteoarthritis (TMJOA) is a degenerative disorder affecting the temporomandibular joint (TMJ), marked by persistent inflammation and structural damage to the joint. Only symptomatic treatment is available for managing TMJOA. Human umbilical cord mesenchymal stem cells (hUC-MSCs) show potential for treating TMJOA via their immune-modulating actions in the disease area. In addition, stimulation of inflammatory cytokines such as interferon-gamma in hUC-MSCs improves the therapeutic activity of naïve stem cells. Emerging evidence indicates that macrophages play significant roles in regulating joint inflammation through diverse secreted mediators in the pathogenesis of TMJOA. This study was conducted to evaluate the effects of inflammatory cytokine-stimulated hUC-MSCs in repairing TMJOA-induced cartilage lesions and the role of macrophages in the disease. Our in vitro data showed that stimulated hUC-MSCs induce M2 polarization of macrophages and enhance the expression of anti-inflammatory molecules. These effects were subsequently validated in vivo. In a rat model of TMJOA, stimulated hUC-MSCs ameliorated inflammation and increased M2 macrophages ratio. Our results indicate that hUC-MSCs stimulated by inflammatory cytokines modulate the activation of M2 macrophages, thereby shifting the local osteoarthritis microenvironment toward a prochondrogenic state and facilitating cartilage repair in inflammatory conditions. Stimulating hUC-MSCs with inflammatory cytokines could potentially offer an effective therapeutic approach for TMJOA, with macrophages playing a pivotal role in immune modulation.

A novel extracellular vesicles production system harnessing matrix homeostasis and macrophage reprogramming mitigates osteoarthritis

Osteoarthritis (OA) is a degenerative disease that significantly impairs quality of life. There is a pressing need for innovative OA therapies. While small extracellular vesicles (sEVs) show promising therapeutic effects against OA, their limited yield restricts clinical translation. Here, we devised a novel production system for sEVs that enhances both their yield and therapeutic properties. By stimulating mesenchymal stem cells (MSCs) using electromagnetic field (EMF) combined with ultrasmall superparamagnetic iron oxide (USPIO) particles, we procured an augmented yield of EMF-USPIO-sEVs. These vesicles not only activate anabolic pathways but also inhibit catabolic activities, and crucially, they promote M2 macrophage polarization, aiding cartilage regeneration. In an OA mouse model triggered by anterior cruciate ligament transection surgery, EMF-USPIO-sEVs reduced OA severity, and augmented matrix synthesis. Moreover, they decelerated OA progression through the microRNA-99b/MFG-E8/NF-κB signaling axis. Consequently, EMF-USPIO-sEVs present a potential therapeutic option for OA, acting by modulating matrix homeostasis and macrophage polarization.

Suramin ameliorates osteoarthritis by acting on the Nrf2/HO-1 and NF-κB signaling pathways in chondrocytes and promoting M2 polarization in macrophages

Osteoarthritis (OA)-the most prevalent of arthritis diseases-is a complicated pathogenesis caused by cartilage degeneration and synovial inflammation. Suramin has been reported to enhance chondrogenic differentiation. However, the therapeutic effect of suramin on OA-induced cartilage destruction has remained unclear. Suramin is an anti-parasitic drug that has potent anti-purinergic properties. This study investigated the protective effects and underlying mechanisms of suramin on articular cartilage degradation using an in vitro study and mice model with post-traumatic OA. We found that suramin markedly suppressed the IL-1β increased expression of matrix destruction proteases-such as ADAMT4, ADAMTS5, MMP3, MMP13, and inflammatory mediators-including the iNOS, COX2, TNFα, and IL-1β; while greatly enhancing the synthesis of cartilage anabolic factors-such as COL2A1, Aggrecan and SOX9 in IL-1β-induced porcine chondrocytes. In vivo experiments showed that intra-articular injection of suramin ameliorated cartilage degeneration and inhibited synovial inflammation in an anterior cruciate ligament transection (ACLT)-induced OA mouse model. In mechanistic studies, we found that exogenous supplementation of suramin can activate Nrf2, and accordingly inhibit the nuclear factor kappa-light-chain-enhancer of activated B cells (NF- κB) and mitogen-activated protein kinase (MAPK) pathways, thereby alleviating the inflammation and ECM degeneration of chondrocytes stimulated by IL-1β. In addition, suramin also repolarized M1 macrophages to the M2 phenotype, further reducing the apoptosis of chondrocytes. Collectively, the results of the study suggests that suramin is a potential drugs which could serve as a facilitating drug for the application of OA therapy toward clinical treatment.

Elucidation of the Underlying Mechanism of Gujian Oral Liquid Acting on Osteoarthritis through Network Pharmacology, Molecular Docking, and Experiment

Gujian oral liquid (GJ), a traditional herbal formula in China, has been widely used to treat patients with osteoarthritis (OA). Nevertheless, the active component and potential mechanism of GJ are not fully elucidated. Thus, we investigate the effect of GJ and explore its underlying mechanism on OA through network pharmacology and experimental validation. First, a total of 175 bioactive compounds were identified, and 134 overlapping targets were acquired after comparing the targets of the GJ with those of OA. 8 hub targets, including IL6 and AKT1, were obtained in PPI network analysis. Then, we built up GJ-target-OA network and protein-protein interaction (PPI) network, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. The results underlined inflammatory tumor necrosis factor (TNF) as a promising signaling pathway of GJ for OA treatment. Moreover, molecular docking also verified the top two active compounds had direct bindings with the top three target genes. Finally, we verified the effect of GJ on OA in vivo and in vitro. In vivo experiments validated that GJ not only significantly attenuated OA phenotypes including articular cartilage degeneration and subchondral bone sclerosis but also reduced the expressions of tumor necrosis factor-α (TNF-α) and p-p65 in articular chondrocytes. Besides, GJ serum also had a protective effect on chondrocytes against inflammation caused by TNF-α in vitro. Hence, our study predicted and verified that GJ could exert anti-inflammation and anticatabolism effects partially via regulating TNF-α/NF-kappa B (NF-κB) signaling.

Anti-inflammatory and immunomodulatory effects of the extracellular vesicles derived from human umbilical cord mesenchymal stem cells on osteoarthritis via M2 macrophages

Osteoarthritis (OA) is a degenerative illness that greatly impacts the life quality of patients. Currently, the therapeutic approaches for OA are very limited in clinical. The extracellular vesicles (EVs) derived from different mesenchymal stem cells displayed a prominent therapeutic effect on OA. But most EVs have limited resources and the risks of host rejection, immunological response, and etc. Human umbilical cord mesenchymal stem cells (hUCMSCs) hold the advantages of easy availability, minimal immune rejection, and excellent immunomodulatory effects, although hUCMSCs-EVs have seldom been applied in OA. Herein, we investigated the potential immunomodulatory and anti-inflammatory effects of hUCMSCs-EVs on the treatment of OA. In our results, the treatment of hUCMSCs-EVs promoted the polarization of M2-type macrophages and the expression of anti-inflammation-related cytokines (IL-10). Notably, the supernate of M2 macrophages induced by hUCMSCs-EVs inhibited the level of inflammation-associated factors in OA chondrocytes caused by IL-1β. Further, injection of hUCMSCs-EVs in the articular lumen ameliorated progression of OA and exerted chondroprotective potential based on the OA joint model created by the surgical transection of the anterior cruciate ligament (ACLT). In addition, we found five highly enriched miRNAs in hUCMSCs-EVs, including has-miR-122-5p, has-miR-148a-3p, has-miR-486-5p, has-miR-let-7a-5p, and has-miR-100-5p by High-throughput sequencing of miRNAs, with targeted genes mainly enriched in the PI3K-Akt signaling pathway. Furthermore, we also detected the protein abundance of hUCMSCs-EVs using liquidation chromatography with tandem quadrupole mass spectrometry (LC–MS/MS) analysis. Thus, our study indicates that hUCMSCs-EVs can alleviate cartilage degradation during the OA progression, mechanically may through delivering key proteins and modulating the PI3K-Akt signaling pathway mediated by miRNAs to promote polarization of M2 macrophage, exhibiting potent immunomodulatory potential. The current findings suggest that hUCMSCs-EVs might serve as a new reagent for the therapy of OA.

Graphical Abstract

miR-31-5p/SOX4 Axis Affects Autophagy and Apoptosis of Chondrocytes by Regulating Extracellular Regulated Protein Kinase/Mechanical Target of Rapamycin Kinase Signalling

BACKGROUND

Osteoarthritis (OA) is a common type of degenerative joint diseases that is regulated by a combination of complex intercellular signals and modulators, including non-coding RNAs. Mounting evidence suggests that miR-31-5p is physiologically involved in the regulation of chondrocytes, but the mechanism remains unclear.

METHODS

Expression levels of miR-31-5p and SOX4 in OA cartilage tissues and in IL-1β-stimulated chondrocytes were examined by quantification polymerase chain reaction (q-PCR) or immunohistochemistry assays. Cell proliferation and apoptosis were detected by Cell Counting Kit-8 (CCK-8) and flow cytometry assays, respectively. Expression of LC3 was detected using immunofluorescence staining. Expressions of autophagy-related proteins and extracellular regulated protein kinase (ERK)/mechanical target of rapamycin kinase (mTORC1) signal-related proteins were measured by Western blot analysis. Molecular interaction was validated by dual luciferase reporter assay.

RESULTS

Downregulation of miR-31-5p and upregulation of SOX4 were observed in both OA patients and OA chondrocytes. Mechanistic experiments revealed that miR-31-5p negatively modulated SOX4 expression by directly targeting its 3'- untranslated region. Moreover, overexpression of miR-31-5p suppressed the activation of mTORC1 in an ERK-dependent manner by inhibiting SOX4. Further functional experiments demonstrated that overexpressing miR-31-5p in OA chondrocytes markedly promoted its proliferation and autophagy while inhibiting apoptosis. However, these effects were abolished by overexpression of SOX4 or treatment with 3BDO, an mTOR activator.

CONCLUSION

These results demonstrated that miR-31-5p enhanced survival and autophagy of OA chondrocytes through inactivation of mTORC1 via directly targeting SOX4, suggesting that miR-31-5p may play a protective role in OA progression.

Differences in knee joint degeneration between primary hip osteoarthritis and hip osteoarthritis secondary to hip developmental dysplasia: A propensity score-based analysis

OBJECTIVES

This study aimed to investigate differences in lower limb alignment and the prevalence of knee osteoarthritis (OA) among patients with primary hip osteoarthritis (PHOA) versus those with hip osteoarthritis secondary to developmental dysplasia of the hip (DDH-OA).

METHODS

We compared 83 patients who underwent primary total hip arthroplasty for unilateral PHOA or DDH-OA after performing propensity score matching. The prevalence of knee OA and lower limb alignment were evaluated on preoperative plain radiographs.

RESULTS

The prevalence of knee OA on the ipsilateral side was significantly higher in the PHOA group than in the DDH-OA group (p =.019), whereas there was no difference between the groups on the contralateral side (p = .631). Lower-limb alignment was more valgus on the ipsilateral side in the DDH-OA group than the PHOA group, whereas it was not significantly different on the contralateral side between groups.

CONCLUSION

The prevalence of knee OA and lower-limb malalignment on the ipsilateral side of hip OA were different for PHOA and DDH-OA patients. Shifting the mechanical axis of lower limbs might be associated with the prevalence of knee OA and lower limb malalignment in the presence of unilateral hip OA.

Prediction and Potential Preventions for the Development of Posttraumatic Osteoarthritis after the Terrible Triad Injury: A Multicenter Risk Factors Study

Objective

A multicenter study to evaluate risk factors for the development of moderate or severe posttraumatic osteoarthritis (PTOA) and to find potential preventions.

Methods

We conducted a retrospective multicenter study including the terrible triad injury (TTI) patients with surgical treatment from January 2007 to November 2014. Demographics, injury information, and treatment history were obtained retrospectively. According to the Broberg and Morrey criterion, 198 included patients were sorted into two groups: the mild or no PTOA and moderate or severe PTOA. Uni- and multivariate logistic regression analyses were used to identify risk factors for moderate or severe PTOA.

Results

Moderate or severe PTOA was present in 64 patients (32.3%). Significant risk factors were Mason III radial head fracture (OR 4.049, 95% CI 1.877-8.736, p < 0.001), medial collateral ligament injury (OR 5.120, 95% CI 1.261-20.790, p = 0.022), and heavy use of elbow (OR 2.333, 95% CI 1.060-5.136, p = 0.035). Besides, patients suffered subluxation (p = 0.007) and those with more risk factors had a higher risk to develop moderate or severe PTOA.

Conclusions

Moderate or severe PTOA was common after the TTI. Patients need to be counseled about avoiding heavy use of the elbow, especially for those with Mason III radial head fractures. Surgeons should be aware of the recurrent instability of the elbow.

Trends in incidence and prevalence of osteoarthritis in the United Kingdom: findings from the Clinical Practice Research Datalink (CPRD)

OBJECTIVE

This study aimed to explore the incidence and prevalence of OA in the UK in 2017 and their trends from 1997 to 2017 using a large nationally representative primary care database.

DESIGN

The UK Clinical Practice Research Datalink (CPRD) comprising data on nearly 17.5 million patients was used for the study. The incidence and prevalence of general practitioner diagnosed OA over a 20 years period (1997-2017) were estimated and age-sex and length of data contribution standardized using the 2017 CPRD population structure. Cohort effects were examined through Age-period-cohort analysis.

RESULTS

During 1997-2017, there were 494,716 incident OA cases aged ≥20 years. The standardised incidence of any OA in 2017 was 6.8 per 1000 person-years (95% CI 6.7 to 6.9) and prevalence was 10.7% (95% CI 10.7-10.8%). Both incidence and prevalence were higher in women than men. The incidence of any-OA decreased gradually in the past 20 years at an annual rate of -1.6% (95%CI -2.0 to -1.1%), and the reduction speeded up for people born after 1960. The prevalence of any-OA increased gradually at an annual rate of 1.4% (95% CI 1.3-1.6%). Although the prevalence was highest in Scotland and Northern Ireland, incidence was highest in the East Midlands. Both incidence and prevalence reported highest in the knee followed by hip, wrist/hand and ankle/foot.

CONCLUSION

In the UK approximately one in 10 adults have symptomatic clinically diagnosed OA, the knee being the commonest. While prevalence has increased and become static after 2008, incidence is slowly declining. Further research is required to understand these changes.

The influence of adipose-derived stromal vascular fraction cells on the treatment of knee osteoarthritis

Background

Adipose-derived stromal vascular fraction (SVF) cells are a mixed cell population that includes cells with multilineage potential, similar to bone marrow-derived mesenchymal stem cells. Our purpose is to investigate the influence of SVF cells in patients with knee osteoarthritis (OA) and the short-term treatment effects.

Methods

Fifty-seven patients were enrolled and treated with intra-articular injection of 2.5 × 10⁷ SVF cells into the knee joint between September 2017 and March 2018. All patients were followed up for 12 months or longer. Mean age at treatment and follow-up period were 69.4 ± 6.9 years and 13.7 ± 2.0 months, respectively. The mean preoperative hip-knee-ankle angle was 6.7 ± 3.6°. SVF cells were prepared using the Celution®800/CRS system from the patients’ abdominal or breech subcutaneous fat. The mean SVF cell viability was 90.6 ± 2.7%. Clinical evaluations were performed for range of motion, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and the Knee injury and Osteoarthritis Score (KOOS). Imaging evaluations, which included the hip-knee-ankle angle assessed via radiography, and T2 mapping value using a 1.5-T magnetic resonance imaging unit were also assessed. Both clinical and imaging evaluations were performed preoperatively, 1, 3, 6, and 12 months postoperatively, and compared among all timepoints (p < 0.05).

Results

Knee extension angle at 6 and 12 months postoperatively was significantly better than the preoperative angle. Total WOMAC, VAS, and KOOS scores at 1, 3, 6 and 12 months postoperatively were significantly better than preoperative scores. There was no significant difference in hip-knee-ankle angle among the five time periods. T2 mapping values of lateral femur and tibia were significantly higher 12 months postoperatively than preoperatively.

Conclusions

The short-term clinical effects of intra-articular SVF cell injection on knee OA were excellent. Intra-articular SVF cell injection is a novel and innovative approach for treating patients with knee OA.

NF-κB Signaling Regulates Physiological and Pathological Chondrogenesis

The nuclear factor-κB (NF-κB) is a transcription factor that regulates the expression of genes that control cell proliferation and apoptosis, as well as genes that respond to inflammation and immune responses. There are two means of NF-κB activation: the classical pathway, which involves the degradation of the inhibitor of κBα (IκBα), and the alternative pathway, which involves the NF-κB-inducing kinase (NIK, also known as MAP3K14). The mouse growth plate consists of the resting zone, proliferative zone, prehypertrophic zone, and hypertrophic zone. The p65 (RelA), which plays a central role in the classical pathway, is expressed throughout the cartilage layer, from the resting zone to the hypertrophic zone. Inhibiting the classical NF-κB signaling pathway blocks growth hormone (GH) or insulin-like growth factor (IGF-1) signaling, suppresses cell proliferation, and suppresses bone morphogenetic protein 2 (BMP2) expression, thereby promoting apoptosis. Since the production of autoantibodies and inflammatory cytokines, such as tumor necrosis factor-α (TNFα), interleukin (IL)-1β, IL-6, and IL-17, are regulated by the classical pathways and are increased in rheumatoid arthritis (RA), NF-κB inhibitors are used to suppress inflammation and joint destruction in RA models. In osteoarthritis (OA) models, the strength of NF-κB-activation is found to regulate the facilitation or suppression of OA. On the other hand, RelB is involved in the alternative pathway, and is expressed in the periarticular zone during the embryonic period of development. The alternative pathway is involved in the generation of chondrocytes in the proliferative zone during physiological conditions, and in the development of RA and OA during pathological conditions. Thus, NF-κB is an important molecule that controls normal development and the pathological destruction of cartilage.

Dietary intake of fatty acids and antioxidants in relation to radiographic knee osteoarthritis: results from a case-control study

BACKGROUND

The present study aimed to investigate levels of nutrient intakes, including dietary antioxidant quality (DAQ) score, among Saudi females with and without knee osteoarthritis (OA). We also aimed to examine the relationship between nutrient intakes and knee OA severity.

METHODS

One hundred female participants with symptomatic primary knee OA were matched for age with 100 apparently healthy females and were sequentially recruited from the Orthopaedics Department, Faculty of Medicine, King Abdulaziz University Hospital, Saudi Arabia, in a case-control study design. Radiographic disease severity of OA was assessed by the Kellgren-Lawrence grading system. Symptomatic severity was evaluated according to the Western Ontario McMaster University Osteoarthritis scores. Dietary intake was assessed using a prevalidated food frequency questionnaire. The DAQ score was calculated considering the risk of an inadequate intake (<2/3 reference nutrient intake) for selenium, zinc, vitamins A, C and E.

RESULTS

A higher intake of saturated fatty acids [15.4 (0.3) as a mean (SD) percentage of energy supplied] and monounsaturated fatty acids [16.6 (0.2) as a percentage of energy supplied] than the recommendations was evident among the study population. OA patients consume less antioxidants than non-OA subjects as determined by their DAQ score [8.41 (0.1) versus 9.17 (0.1), P < 0.0001]. After adjusting for potential confounders, DAQ score, and monounsaturated and polyunsaturated fatty acids, most of the micronutrient intakes were found to be negatively associated with the prevalence of radiographic knee OA.

CONCLUSIONS

Dietary antioxidants could be implicated in the development and progression of knee OA. Modifying dietary fatty acids may be one way of reducing the development and subsequent burden of knee OA.

Therapeutic effect of mesenchymal stem cells derived from human umbilical cord in rabbit temporomandibular joint model of osteoarthritis

Osteoarthritis (OA) is a degenerative condition of the temporomandibular joint (TMJ) characterised by chronic inflammation and damage to joint structures. Because of the complexity of TMJ-OA, only symptomatic treatments are currently available. Recent reports have shown that many of stem cells can exert anti-inflammatory and tissue-regenerating effects. In this study, we investigated the potential cartilage-regenerating and anti-inflammatory effects of human umbilical cord matrix-mesenchymal stem cells (hUCM-MSCs) for the treatment of TMJ-OA. hUCM-MSC lines, isolated from different donors, which showed different activities in vitro. Using a selected cell line, we used different concentrations of hUCM-MSCs to assess therapeutic effects in a rabbit model of monosodium iodoacetate-induced TMJ-OA. Compared with the untreated control group, the potential regenerative result and anti-inflammatory effects of hUCM-MSCs were evident at all the tested concentrations in rabbits with induced TMJ-OA. The median dose of hUCM-MSCs showed the prominent cartilage protective effect and further cartilage regeneration potential. This effect occurred via upregulated expression of growth factors, extracellular matrix markers, and anti-inflammatory cytokines, and reduced expression of pro-inflammatory cytokines. The anti-inflammatory effect of hUCM-MSCs was comparable to that of dexamethasone (DEX). However, only hUCM-MSCs showed potential chondrogenesis effects in this study. In conclusion, our results indicate that hUCM-MSCs may be an effective treatment option for the treatment of TMJ-OA.

Association between ADIPOQ gene variants and knee osteoarthritis in a Chinese population

A study from Thailand showed no significant association between the adiponectin (ADIPOQ) gene rs1501299 polymorphism and knee osteoarthritis (OA) risk. To investigate this association in a Chinese population, we conducted this case-control study involving 372 knee OA patients and 453 controls. Genotyping via standard PCR and restriction fragment length polymorphism (PCR-RFLP) showed that TT genotype (TT vs. GG: adjusted odds ratio (OR) (95% confidence interval (CI)) = 1.70 (1.01-2.86)) or T allele (T vs. G: adjusted OR (95% CI) = 1.26 (1.02-1.56)) of ADIPOQ gene rs1501299 polymorphism significantly increased the risk of knee OA. Significant associations were also observed in subgroups ≥55 years (TT vs. GG: adjusted OR (95% CI) = 2.21 (1.00-4.86)) and body mass index (BMI) < 25 kg/m² (TT+GT vs. GG: adjusted OR (95% CI) = 1.53 (1.03-2.29)), but not in the subgroup analysis of sex. In conclusion, the ADIPOQ gene rs1501299 polymorphism intensifies the risk of knee OA in this Chinese Han population. Nevertheless, further studies with larger sample sizes in other populations are warranted to verify this finding.

The effect of a portable electrical muscle stimulation device at home on muscle strength and activation patterns in locomotive syndrome patients: A randomized control trial

The aim of the present study was to quantify the effect of electrical muscle stimulation (EMS) intervention using a portable device on muscle strength and activation patterns in locomotive syndrome. Nineteen women were randomly assigned to the intervention group (n = 10; age = 71-82 years) and control group (n = 9; age = 70-84 years). Participants in the intervention group used a portable EMS device to stimulate the bilateral quadriceps muscles for 8 weeks (23 min/5 days/week). To understand the effects of EMS, the following measurements were made at baseline, 8 weeks, and 12 weeks: locomotive syndrome assessment score, knee extensor strength, vastus lateralis muscle activation patterns during a maximal isometric knee extension contraction using multi-channel surface electromyography, and muscle thickness. The locomotive syndrome assessment, muscle strength, muscle thickness, and muscle activity patterns in the intervention group were significantly different to control after 8 weeks (p < 0.05). However, these results were not sustained at 12 weeks. EMS increased locomotor assessment scores, which were accompanied by enhanced muscle strength, increased muscle thickness, and changes in muscle activation patterns in locomotive syndrome patients. These results suggest that EMS is potentially useful for improving muscle neural activation and force output in locomotive syndrome.

Prevalence of osteoarthritis and association between smoking patterns and osteoarthritis in China: a cross-sectional study

Objective

The aims of this study were to estimate the prevalence of radiographic osteoarthritis (OA) and to assess the association between smoking patterns and OA prevalence in adults aged 50 years or older belonging to the Shanxi province of China.

Methods

A cross-sectional study in the rural regions of the Shanxi province was conducted among 2638 Chinese adults (aged ≥50 years). Demographic characteristics and behavioral information were collected through epidemiological surveys. All participants with joint pain underwent plain radiographic examination and were diagnosed by a professional orthopedist. Associations between smoking patterns and the prevalence of OA were assessed using binary logistic regression modeling.

Results

Among 2638 individuals (men, 50.3% and women, 49.7%; mean age, 61.5 years) included in the analysis, 49.8% had radiographic OA and 27.5% had knee OA. The prevalence of radiographic OA was higher in women than in men (P<0.001). After adjusting for potential confounding factors, there was a nonsignificant correlation between smoking and OA prevalence in the multivariate model. Odds ratios (ORs) for all types of OA and knee OA were higher in active and passive smokers than in nonsmoking individuals after adjustments (OR 1.374; 95% confidence interval [CI] 1.049–1.802; OR 1.440; 95% CI 1.059–1.958, respectively).

Conclusions

This study showed that smoking may not be an independent risk factor for OA; however, there was a positive correlation between active and passive smoking and OA.

Can osteophytes be used as age at death estimators? Testing correlations in skeletonized human remains with known age-at-death

Age-at-death estimation is one of the major challenges when establishing an adult skeleton biological profile. The presence of degenerative joint changes - e.g. osteophytes - has been regarded as a good postmaturity age indicator. This study assessed if a clear relationship between age and osteophytes exists. To accomplish this goal, a total of 16 joint surfaces, from the shoulder, elbow, wrist, hip, knee, and ankle, were examined in 604 adult individuals, of both sexes from two Portuguese Identified collections. Individuals had between 20 and 98 year old at death. Statistically significant results were found between age-at-death and degrees of severity of osteophytes throughout all the articular surfaces analyzed (p>0.001). However, the strength of the correlation varies from moderate to low in the majority of the joints, for both sexes. The only strong correlation effects (r=0.567 in females and r=0.552 in males) were found associated with the left and right glenoid cavity in females and males respectively. More noticeable changes were consistently found in association with older individuals (>62 years old). Results indicate that significant relationships exist between age and the presence of osteophytes in the joint margins. However, correlation effects were low to moderate in most cases, therefore the use of osteophytes to predict age-at-death is not without significant error of interpretation.

Electro-Acupuncture is Beneficial for Knee Osteoarthritis: The Evidence from Meta-Analysis of Randomized Controlled Trials

Knee osteoarthritis (KOA) is a common chronic degenerative disease of the elderly. Electro-acupuncture (EA) is considered as a beneficial treatment for KOA, but the conclusion is controversial. This systematic review compiled the evidence from 11 randomized controlled trials to objectively assess the effectiveness and safety of EA for KOA. Eight databases including PubMed, Cochrane Library, Clinic trials, Foreign Medical Literature Retrial Service (FMRS), Science Direct, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journal Database (VIP), and Wanfang Data were extensively searched up to 5 July 2016. The outcomes included the evaluation of effectiveness, pain and physical function. Risk of bias was evaluated according to the Cochrane risk of bias tool. Eleven RCTs with 695 participants were included. Meta-analysis indicated that EA was more effective than pharmacological treatment (RR [Formula: see text] 1.14; 95% CI [Formula: see text] 1.01,1.28; [Formula: see text]) and manual acupuncture (RR [Formula: see text] 1.12; 95% CI [Formula: see text] 1.02,1.22; [Formula: see text]). Also, EA had a more significant effect in reducing the pain intensity (SMD [Formula: see text]; 95% CI [Formula: see text]; [Formula: see text]) and improving the physical function in the perspective of WOMAC (MD [Formula: see text]; 95% CI [Formula: see text], 5.56; [Formula: see text]) and LKSS (pharmacological treatment: MD [Formula: see text]; 95% CI [Formula: see text], 6.64; [Formula: see text]). Furthermore, these studies implied that EA should be performed for at least 4 weeks. Conclusively, the results indicate that EA is a great opportunity to remarkably alleviate the pain and improve the physical function of KOA patients with a low risk of adverse reaction. Therefore, more high quality RCTs with rigorous methods of design, measurement and evaluation are needed to confirm the long-term effects of EA for KOA.

Clinical efficacy of certain Unani herbs in knee osteoarthritis: A pretest and post-test evaluation study

Objectives:

This study was conducted to evaluate the efficacy of preparations of certain Unani herbs on Lequesne Algo-Functional Index of knee osteoarthritis (OA).

Materials and Methods:

A prospective, pre- and post test evaluation study was conducted on 20 diagnosed patients of OA recruited from the Nizamia General Hospital, Hyderabad. Internally, a combination (formula) of Unani herbs was administered, which was as follows: 3.5 g powder of Asarun (2 g), Tukhme karafs (2 g), and Filfil daraz (3 g) was administered internally twice daily. Externally, the concoction of Gule baboona (20 g) and Gule tesu (40 g) made in 1 l water was poured over the affected knee, daily once for 40 days. The primary outcome was to assess the efficacy of Unani test drugs with the modified Lequesne Algo-Functional Index for knee OA.

Results:

The mean percentage reduction of Lequesne Algo-Functional Index score was 71.09%. The mean and standard deviation was 10.55 (1.70) and 3.05 (2.30) before treatment and after treatment, respectively. The pre- and post test evaluation showed reduction in Lequesne Algo-Functional Index score (P < 0.0001).

Conclusion:

In this study, the Unani treatment module was found to be effective in reducing the severity of disease in patients with osteoarthritis of knees.

Evaluation of body mass index as a prognostic factor in osteoarthrosis of the knee

OBJECTIVE

To evaluate the relationship between patients' body mass index (BMI) and the degree of radiographic severity of knee osteoarthrosis.

METHOD

117 patients with gonarthrosis were evaluated prospectively. The patients' BMI was calculated and their knee arthrosis was classified in accordance with the modified Ahlbäck criteria. Kruskal-Wallis analysis of variance (ANOVA) was used to evaluate the relationship between these two variables.

RESULTS

The group classified as Ahlbäck grade V had significantly higher BMI than the others.

CONCLUSION

There is a direct relationship between BMI and the degree of radiographic severity of gonarthrosis. Obesity appears to be directly related to the progression of knee osteoarthrosis.

Osteoarthritis prevalence and modifiable factors: a population study

BACKGROUND

This study's objectives were to investigate the prevalence of self-reported knee and hip osteoarthritis (OA) stratified by age and sex and to examine the association of modifiable factors with knee and hip OA prevalence. The study was conducted using randomly sampled data gathered from four communities in the province of Alberta, Canada.

METHODS

A large adult population sample (N = 4733) of individuals ≥18 years were selected. Health-related information was collected through telephone interviews and community measurement clinics for which a sub-sample (N = 1808) attended. Participants self-reported OA during telephone interviews. Clinic interviews further assessed if the diagnosis was made by a health care professional. Statistical analyses compared prevalence of OA between sexes and across age categories. Associations between modifiable factors for OA and the prevalence of knee and hip OA were assessed using binary logistic regression modelling.

RESULTS

Overall prevalence of self-reported OA in the total sample was 14.8 %, where 10.5 % of individuals reported having knee OA and 8.5 % reported having hip OA. Differences in prevalence were found for males and females across age categories for both knee and hip OA. In terms of modifiable factors, being obese (BMI >30 kg/m2) was significantly associated with the prevalence of knee (OR: 4.37; 95 % CI: 2.08,9.20) and hip (OR: 2.52; 95 % CI: 1.17,5.43) OA. Individuals who stand or walk a lot, but do not carry or lift things during their occupational activities were 2.0 times less likely to have hip OA (OR: 0.50; 95 % CI: 0.26,0.96). Individuals who usually lift or carry light loads or have to climb stairs or hills were 2.2 times less likely to have hip OA (OR: 0.45; 95 % CI: 0.21,0.95). The odds of having hip OA were 1.9 times lower in individuals consuming recommended or higher vitamin C intake (OR: 0.52; 95 % CI: 0.29,0.96). Significant differences in prevalence were found for both males and females across age categories.

CONCLUSION

The prevalence of knee and hip OA obtained in this study is comparable to other studies. Females have greater knee OA prevalence and a greater proportion of women have mobility limitations as well as hip and knee pain; it is important to target this sub-group.

Predictive value of semi-quantitative MRI-based scoring systems for future knee replacement: data from the osteoarthritis initiative

PURPOSE

To evaluate, in a confirmatory fashion, whether baseline and change from baseline to 24-month follow-up in cartilage damage, bone marrow lesions and meniscal damage are predictors of knee replacement (KR) in subjects with a high risk of osteoarthritis (OA), independent of the level of physical activity, symptom severity and radiographic abnormalities.

METHODS

Data from the Osteoarthritis Initiative's (OAI) baseline and 24-month follow-up knee MRIs of 115 patients (age range: 45-78 years; 48 % female; BMI: 20.9-48.7) were analyzed. Cartilage, bone marrow and menisci were semi-quantitatively scored according to the Whole-Organ Magnetic Resonance Imaging Score (WORMS) and Boston-Leeds Osteoarthritis Knee Score (BLOKS) systems in all compartments. Baseline and 24-month interval changes in structural tissue damage assessed by BLOKS and WORMS were used as predictors of KR independent of clinical and radiographic parameters using Cox hazard analysis. Adjustments were performed for age, gender, BMI and physical activity (Physical Activity Scale for the Elderly: PASE), Western Ontario and McMaster Questionnaire (WOMAC) total score and radiographic Kellgren-Lawrence (KL) score.

RESULTS

BLOKS and WORMS baseline cartilage scores were predictors of KR independent of the PASE, WOMAC and KL score. One score increase in the average baseline BLOKS full-thickness cartilage defect score was associated with a [hazard ratio (95 % CI)] 13.55 (3.61-50.89) times greater risk of KR independent of the PASE, WOMAC and KL score. Net reclassification improvements (NRIs) of the additional evaluation of 24-month follow-up MRI scores and assessment of changes were not significant for prediction of KR (NRI range: - 7.23 - 24.8 %).

CONCLUSIONS

The BLOKS cartilage score for full-thickness cartilage defects had the highest hazard for KR. Follow-up MRI changes in structural tissue damage, detected by BLOKS and WORMS cartilage, bone marrow or meniscus scores (up to 24 months) had no significant predictive value in addition to the baseline MRI.

Association of adipokines and joint biomarkers with cartilage-modifying effects of weight loss in obese subjects

OBJECTIVES

To determine (1) the effects of weight loss in obese subjects on six adipokines and joint biomarkers; and (2) the relationship between changes in these markers with changes in cartilage outcomes.

DESIGN

Plasma levels of adiponectin, leptin, IL-6, COMP, MMP-3 and urine levels of CTX-II were measured at baseline and 12 months from 75 obese subjects enrolled in two weight-loss programs. Magnetic resonance imaging (MRI) was used to assess cartilage volume and thickness. Associations between weight loss, cartilage outcomes and markers were adjusted for age, gender, baseline BMI, presence of clinical knee OA, with and without weight loss percent.

RESULTS

Mean weight loss was 13.0 ± 9.5%. Greater weight loss percentage was associated with an increase in adiponectin (β = 0.019, 95% CI 0.012 to 0.026,) and a decrease in leptin (β = -1.09, 95% CI -1.37 to -0.82). Multiple regression analysis saw an increase in adiponectin associated with reduced loss of medial tibial cartilage volume (β = 14.4, CI 2.6 to 26.3) and medial femoral cartilage volume (β = 18.1, 95% CI 4.4 to 31.8). Decrease in leptin was associated with reduced loss of medial femoral volume (β = -4.1, 95% CI -6.8 to -1.4) and lateral femoral volume (β = -1.8, 95% CI -3.7 to 0.0). When weight loss percent was included in the model, only the relationships between COMP and cartilage volume remained statistically significant.

CONCLUSIONS

Adiponectin and leptin may be associated with cartilage loss. Further work will determine the relative contributions of metabolic and mechanical factors in the obesity-related joint changes.

Anticipated significant work limitation in primary care consulters with osteoarthritis: a prospective cohort study

OBJECTIVE

To describe the prevalence of expected work limitations (EWL) prior to future retirement age in osteoarthritis consulters, and the associated health, sociodemographic and workplace factors.

DESIGN

Population-based prospective cohort study.

SETTING

General practices in Staffordshire, England.

PARTICIPANTS

297 working adults aged 50-65, who had consulted primary care for osteoarthritis.

OUTCOME

EWL was defined using a single question, "Do you think joint pain will limit your ability to work before you reach 69 years old?"

RESULTS

51 (17.2%) indicated that joint pain would not limit their ability to work until 69, 79 (26.6%) indicated EWL and 167 (56.2%) did not know if joint pain would limit work before 69. In bivariate analysis, physical function (OR 0.93; 95% CI 0.91 to 0.96), depression (4.51; 1.81 to 11.3), cognitive symptom (3.84; 1.81 to 8.18), current smoker (2.75; 1.02 to 7.38), age (0.69; 0.58 to 0.82), physically demanding job (3.18; 1.50 to 6.72), no opportunities to retrain (3.01; 1.29 to 7.05) and work dissatisfaction (3.69; 1.43 to 9.49) were associated with EWL. The final multivariate model included physical function and age.

CONCLUSIONS

Only one in five osteoarthritis consulters expected that joint pain would not limit their work participation before 69 years of age. Given the expectation for people to work until they are older, the results highlight the increasing need for clinicians to include work participation in their consultation and implement strategies to address work loss/limitation. Targeting pain-related functional limitation and effective communication with employers to manage workplace issues could reduce EWL.

Reasons why multimorbidity increases the risk of participation restriction in older adults with lower extremity osteoarthritis: a prospective cohort study in primary care

OBJECTIVE

To determine why multimorbidity causes participation restriction in adults ages ≥50 years who consult primary care with lower extremity osteoarthritis (OA).

METHODS

This was a population-based prospective cohort study of 1,053 consulters for lower extremity OA who were free of participation restriction at baseline. Path analysis was used to test proposed mechanisms by examining for mediation of the association between multimorbidity at baseline, defined by self-report and consultation data separately, and incident participation restriction at 3 years by lower extremity pain severity, obesity, locomotor disability, and depression.

RESULTS

Multimorbidity was associated with incident participation restriction (adjusted odds ratio [OR] 2.83, 95% confidence interval [95% CI] 2.03-3.94 for multimorbidity [self-report]; OR 1.59, 95% CI 1.15-2.21 for multimorbidity [consultation data]). The extent of mediation of the association of baseline multimorbidity, defined by self-report, and incident participation restriction was greater for severe lower extremity pain than obesity (standardized beta coefficients for indirect effect 0.032 [SE 0.015] and 0.020 [SE 0.019], respectively). The addition of depression and locomotor disability increased the amount of mediation (0.115 [SE 0.028]) and reduced the proportion explained by severe lower extremity pain (0.014 [SE 0.015]) and obesity (0.006 [SE 0.010]). Locomotor disability was the strongest mediator.

CONCLUSION

The additional impact on participation in social and domestic life that multimorbidity places on individuals with lower extremity OA appears to be mediated through further restriction of locomotor disability, as well as through depression. The results suggest that the effect of multimorbidity on the daily lives of people with lower extremity OA will be ameliorated by active management of depression and locomotor disability.

Obese patients undergoing total knee arthroplasty have distinct preoperative characteristics: an institutional study of 4718 patients

Obesity affects a disproportionate proportion of total knee arthroplasty (TKA) patients. Our study explores pre-operative characteristics between obese and non-obese patients undergoing TKA surgery. A cohort of 4718 osteoarthritic patients, undergoing primary TKA, was studied. Patients were stratified according to BMI classes. Each class was compared in terms of age, race, gender, level of education, insurance status, pre-operative WOMAC, SF-36, and Elixhauser comorbidities. There was a positive relationship between BMI and female gender, non-white race, Medicaid, private insurance, and self-pay. A negative relationship was observed between BMI and age, Medicare, WOMAC and SF-36. Obese TKA candidates differ from their non-obese counterparts in a number of demographic, socioeconomic, and clinical characteristics.

Onset of work restriction in employed adults with lower limb joint pain: individual factors and area-level socioeconomic conditions

PURPOSE

To examine individual and area-level socioeconomic factors that predict the onset of work restriction in employed persons with lower limb joint pain.

METHODS

Population-based prospective cohort study. Adults were aged 50-59, reported hip, knee, foot pain or a combination and maintained employment through 3 year follow-up (n = 716). Work restriction was measured as inability to participate in work as desired. Multi-level logistic regression was used to assess the associations of work restriction onset with baseline factors: health (severity of knee pain/functional limitation, comorbidity, anxiety, depression, cognitive impairment, abnormal weight), demographic socio-economic, environment and area-level employment deprivation.

RESULTS

108 (15.1 %) reported the onset of work restriction over 3 years. Severe lower limb joint pain and functional limitation, number of affected body sites and area employment deprivation were independently associated with onset. Significant interactions indicated a greater effect of area employment deprivation on older and more depressed workers.

CONCLUSIONS

Results suggest that effectively preventing work disability in those with OA will require both condition-specific interventions to decrease pain and maintain function, and providing alternative employment opportunities for those with progressive functional limitations. Results in older workers are particularly concerning, as retirement ages are expected to increase in the general population.

Knee laxity after staircase exercise predicts radiographic disease progression in medial compartment knee osteoarthritis

OBJECTIVE

To evaluate whether increased laxity of the knee during daily physical activities such as stair climbing is associated with progression of knee joint osteoarthritis (OA).

METHODS

During the years 2001-2003, 136 patients with bilateral primary medial compartment knee joint OA were enrolled in this prospective study. Baseline data collected were body mass index (BMI), muscle power, radiographic joint space width, mechanical axis on standing radiography, and anteroposterior (AP) knee laxity before and after physical exercise. After 8 years of followup, 84 patients were reexamined to assess radiographic changes. Radiographic disease progression was defined as progression of >1 grade on the Kellgren/Lawrence scale.

RESULTS

AP knee laxity increased significantly after stair climbing. Patients with OA progression and those without progression did not differ significantly in age, sex, baseline quadriceps muscle strength, mechanical axis, joint space width, and AP knee laxity before exercise. The 2 groups of patients did, however, differ significantly in baseline BMI and change in AP knee laxity due to exercise. The risk of progression of knee OA increased 4.15-fold with each millimeter of increase in the change in AP knee laxity due to exercise and 1.24-fold with each point increase in the BMI.

CONCLUSION

Our results indicate that patients with OA progression have significantly greater changes in knee joint laxity during physical activities and a higher BMI than patients without OA progression. These findings suggest that larger changes in knee laxity during repetitive physical activities and a higher BMI play significant roles in the progression of knee OA.

The influence of obesity on total joint arthroplasty

Obesity is an epidemic across both the developed and developing nations that is possibly the most important current public health factor affecting the morbidity and mortality of the global population. Obese patients have the potential to pose several challenges for arthroplasty surgeons from the standpoint of the influence obesity has on osteoarthritic symptoms, their peri-operative medical management, the increased intra-operative technical demands on the surgeon, the intra- and post-operative complications, the long term outcomes of total hip and knee arthroplasty. Also, there is no consensus on the role the arthroplasty surgeon should have in facilitating weight loss for these patients, nor whether obesity should affect the access to arthroplasty procedures.

Joint loading decreased by inexpensive and minimalist footwear in elderly women with knee osteoarthritis during stair descent

OBJECTIVE

Previous studies indicate that flexible footwear, which mimics the biomechanics of walking barefoot, results in decreased knee loads in patients with knee osteoarthritis (OA) during walking. However, the effect of flexible footwear on other activities of daily living, such as descending stairs, remains unclear. Our objective was to evaluate the influence of inexpensive and minimalist footwear (Moleca) on knee adduction moment (KAM) during stair descent of elderly women with and without knee OA.

METHODS

Thirty-four elderly women were equally divided into an OA group and a control group (CG). Stair descent was evaluated in barefoot condition, while wearing the Moleca, and while wearing heeled shoes. Kinematics and ground reaction forces were measured to calculate KAM by using inverse dynamics.

RESULTS

The OA group experienced a higher KAM during midstance under the barefoot condition (233.3%; P = 0.028), the Moleca (379.2%; P = 0.004), and heeled shoes (217.6%; P = 0.007). The OA group had a similar knee load during early, mid, and late stance with the Moleca compared with the barefoot condition. Heeled shoes increased the knee loads during the early-stance (versus barefoot [16.7%; P < 0.001] and versus the Moleca [15.5%; P < 0.001]), midstance (versus barefoot [8.6%; P = 0.014] and versus the Moleca [9.5%; P = 0.010]), and late-stance phase (versus barefoot [10.6%; P = 0.003] and versus the Moleca [9.2%; P < 0.001]). In the CG, the Moleca produced a knee load similar to the barefoot condition only during the early-stance phase.

CONCLUSION

Besides the general foot protection, the inexpensive and minimalist footwear contributes to decreasing knee loads in elderly women with OA during stair descent. The loads are similar to the barefoot condition and effectively decreased when compared with heeled shoes.

Effect of in vitro chondrogenic differentiation of autologous mesenchymal stem cells on cartilage and subchondral cancellous bone repair in osteoarthritis of temporomandibular joint

This study investigated the effects of in vitro chondrogenic differentiated mesenchymal stem cells (MSCs) on cartilage and subchondral cancellous bone in temporomandibular joint osteoarthritis (TMJOA). Four weeks after induction of osteoarthritis (OA), the joints received hylartin solution, non-chondrogenic MSCs or in vitro chondrogenic differentiated MSCs. The changes in cartilage and subchondral cancellous bone were evaluated by histology, reverse transcription polymerase chain reaction and micro-computed tomography (CT). Implanted cells were tracked using Adeno-LacZ labelling. The differentiated MSC-treated group had better histology than the MSC-treated group at 4 and 12 weeks, but no difference at 24 weeks. Increased mRNA expression of collegan II, aggeran, Sox9 and decreased matrix metalloproteinase 13 (MMP13) were observed in differentiated MSC-treated groups compared to the undifferentiated MSC-treated group at 4 weeks. The differentiated MSC-treated group had decreased bone volume fraction, trabecular thickness and bone surface density, and increased trabecular spacing in the subchondral cancellous bone than the undifferentiated MSC-treated group. Transplanted cells were observed at cartilage, subchondral bone, and the synovial membrane lining at 4 weeks. Intra-articular injection of MSCs could delay the progression of TMJOA, and in vitro chondrogenic induction of MSCs could enhance the therapeutic effects. This provides new insights into the role of MSCs in cell-based therapies for TMJOA.

Osteoarthritis of the knee at 3.0 T: comparison of a quantitative and a semi-quantitative score for the assessment of the extent of cartilage lesion and bone marrow edema pattern in a 24-month longitudinal study

OBJECTIVE

To compare a semi-quantitative and a quantitative morphological score for assessment of early osteoarthritis (OA) evolution.

MATERIALS AND METHODS

3.0 T MRI of the knee was performed in 60 women, 30 with early OA (each 15 with Kellgren-Lawrence grade 2 and 3) and 30 age-matched controls at baseline and at 12 and 24 months. Pathological condition was assessed with the whole-organ magnetic resonance imaging score (WORMS). Cartilage abnormalities and bone marrow edema pattern (BMEP) were also quantified using a previously introduced morphological quantitative score. These data were correlated with changes in clinical parameters and joint space width using generalized estimation equations (GEE).

RESULTS

At baseline, OA patients had significantly (p < 0.05) more and larger cartilage lesions and BMEP. During follow-up, cartilage lesions increased significantly (p < 0.05) in the patients compared with controls: WORMS showed progression only at the lateral patella, whereas the quantitative score revealed progression additionally at the trochlea and at the medial compartment. Both scores showed a significant (p < 0.05) increase in BMEP at the lateral femur in OA patients. In addition, quantitative scores of BMEP of the whole knee decreased significantly (p < 0.05) after 12 months and increased after 24 months in the patients, but showed an increase in controls at all follow-up examinations. Only weak correlations between structural imaging findings and clinical parameters were observed.

CONCLUSION

Quantitative assessment of cartilage lesions and BMEP is more sensitive to changes during the course of the disease than semi-quantitative scoring. However, structural imaging findings do not correlate well with the clinical progression of OA.

Inexpensive footwear decreases joint loading in elderly women with knee osteoarthritis

Recent literature has highlighted that the flexibility of walking barefoot reduces overload in individuals with knee osteoarthritis (OA). As such, the aim of this study was to evaluate the effects of inexpensive, flexible, non-heeled footwear (Moleca) as compared with a modern heeled shoes and walking barefoot on the knee adduction moment (KAM) during gait in elderly women with and without knee OA. The gait of 45 elderly women between 60 and 70 years of age was evaluated. Twenty-one had knee OA graded 2 or 3 according to Kellgren and Lawrence's criteria, and 24 who had no OA comprised the control group (CG). The gait conditions were: barefoot, Moleca, and modern heeled shoes. Three-dimensional kinematics and ground reaction forces were measured to calculate KAM by inverse dynamics. For both groups, the Moleca provided peak KAM and KAM impulse similar to barefoot walking. For the OA group, the Moleca reduced KAM even more as compared to the barefoot condition during midstance. On the other hand, the modern heeled shoes increased this variable in both groups. Inexpensive, flexible, and non-heeled footwear provided loading on the knee joint similar to a barefoot gait and significant overload decreases in elderly women with and without knee OA, compared to modern heeled shoes. During midstance, the Moleca also allowed greater reduction in the knee joint loads as compared to barefoot gait in elderly women with knee OA, with the further advantage of providing external foot protection during gait.

Experimental osteoarthritis induced by surgical realignment of the patella in BALB/c mice

The patellofemoral joint is an important source of symptoms in osteoarthritis of the knee. We have used a newly designed surgical model of patellar strengthening to induce osteoarthritis in BALB/c mice and to establish markers by investigating the relationship between osteoarthritis and synovial levels of matrix metalloproteinases (MMPs). Osteoarthritis was induced by using this microsurgical technique under direct vision without involving the cavity of the knee. Degeneration of cartilage was assessed by the Mankin score and synovial tissue was used to determine the mRNA expression levels of MMPs. Irrigation fluid from the knee was used to measure the concentrations of MMP-3 and MMP-9. Analysis of cartilage degeneration was correlated with the levels of expression of MMP.

After operation the patellofemoral joint showed evidence of mild osteoarthritis at eight weeks and further degenerative changes by 12 weeks. The level of synovial MMP-9 mRNA correlated with the Mankin score at eight weeks, but not at 12 weeks. The levels of MMP-2, MMP-3 and MMP-14 mRNA correlated with the Mankin score at 12 weeks. An increase in MMP-3 was observed from four weeks up to 16 weeks. MMP-9 was notably increased at eight weeks, but the concentration at 16 weeks had decreased to the level observed at four weeks.

Our observations suggest that MMP-2, MMP-3 and MMP-14 could be used as markers of the progression of osteoarthritic change.

Osteoarthritis in Women: Effects of Estrogen, Obesity and Physical Activity

Arthritis is the leading cause of physical disability in the USA and osteoarthritis (OA), the most common form, affects nearly 27 million people. Women have a higher prevalence of OA than men, but the underlying causes for the increased susceptibility of women to OA are not fully understood. This review discusses the associations of sex hormones, obesity and physical activity with the incidence and progression of OA in women. Although many studies have explored the relationships of estrogen and reproductive history with the risk of OA or joint replacement, there is no consensus on the role of these factors. Obesity clearly increases risk for OA, but whether obesity affects women and men differently is uncertain. Moderate levels of physical activity do not appear to increase the incidence or progression of OA and may even have a weak protective effect. Future investigations should focus on sex-specific mechanisms for the development of OA and determine whether there are modifiable factors (e.g., estrogen, obesity, physical activity) that can be targeted through prevention and treatment strategies to mitigate the increased incidence and prevalence of OA in women.

The Chitranjan Ranawat Award: functional outcome after total knee replacement varies with patient attributes

Total knee replacement effectively relieves arthritis pain but improvement in physical function varies. A clearer understanding of the patient attributes associated with differing levels of functional gain after TKR is critical to surgical decision making. We reviewed 8050 primary, unilateral TKR patients enrolled in a prospective registry between 2000 and 2005 who had complete data. We evaluated associations between 12-month function (SF12/PCS) and preoperative gender, age, BMI, emotional health (MCS), knee diagnosis, quadriceps strength, and physical function (PCS). More than 98% of patients reported pain relief (KS pain score). At 12 months, mean PCS gain was 13.6 points, but the distribution was bimodal. The mean gain in PCS in the 63% of patients with greater improvement was 21 (SD = 7), and 4.1 (SD = 7) in the remaining 37%. Increased likelihood of poor functional gain was associated with older age, body mass index (BMI) over 40, lower MCS, and poor quadriceps strength. While two-thirds of patients reported functional gain well above national average at 12 months post-TKR, 37% reported limited functional improvement. Further understanding of the patient attributes associated with limited improvement will guide the design of innovative strategies to improve functional outcomes.

LEVEL OF EVIDENCE

Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Enhancing lifestyle for individuals with haemophilia through physical activity and exercise: the role of physiotherapy

For individuals with haemophilia, the benefits of many forms of physical activity outweigh their risks. Although activities with significant trauma risk should be avoided, persons who have haemophilia can participate in, enjoy and even excel in a variety of physical activities and sports. Both the National Hemophilia Foundation and the World Foundation of Hemophilia have produced documents to guide individuals with haemophilia and their healthcare professionals, coaches and parents in developing physical activity programmes and participation in sports. Physical activity guidelines for promoting health benefits exist worldwide and can be incorporated into individualized exercise programmes to ensure that a person with haemophilia is not only choosing appropriate activities, but also improving overall health and preparing the body to manage haemophilia better. Physiotherapy treatment is paramount in helping individuals prevent, manage and optimally recover from bleeds. Furthermore, the physical therapist, along with the haemophilia care team, can assist in preparing an individual to begin or progress to a physical activity programme that enhances fitness level, body composition and overall well-being. This article presents the unique role of the physiotherapist in facilitating safe participation in quality physical activity in the context of risks, benefits and activity recommendations. Participation in physical activity from an early age is ideal to facilitate the development of body awareness and capability and to foster the adoption of a physically active lifestyle; however, it is never too late to start. Consistent participation in quality physical activity beginning at any age is central to managing haemophilia and, equally important, to achieving overall health and well-being.

Knee Strength Maintained Despite Loss of Lean Body Mass During Weight Loss in Older Obese Adults With Knee Osteoarthritis

BACKGROUND

The effects of weight loss on muscle function in older adults have not been well studied. This study determined the effects of a 6-month weight-loss intervention on muscle strength and quality in older obese adults with knee osteoarthritis.

METHODS

Participants were randomized to a weight loss (WL) (n = 44, 70 +/- 6 years) or weight stable (WS) (n = 43, 69 +/- 6 years) group. The WL intervention consisted of weekly educational meetings, a meal replacement diet, and a three-session-per-week structured exercise program to achieve 10%-12% weight loss. The WS intervention included bimonthly group meetings and newsletters. Body composition and knee extensor strength were measured at baseline and after intervention.

RESULTS

The WL group decreased body weight, lean body mass, fat mass, and percent body fat (p <.001 for all). Concentric extension strength increased 25% in WL (p >.05), whereas eccentric extension decreased 6% in WS (p =.028). Concentric muscle quality (strength per kg body weight or lean body mass) increased in WL (p <.05), whereas eccentric muscle quality decreased in WS (p <.05). Changes in lean body mass and fat mass were inversely associated with changes in most muscle strength and quality measures (p <.05). Men and women did not differ in response to the intervention in knee strength outcomes.

CONCLUSIONS

Hypocaloric dieting in combination with exercise training had beneficial effects on muscle strength/quality, despite loss of lean body mass in this sample of older men and women. Greater fat loss was associated with greater gains in muscle strength and quality. More studies are needed regarding the mechanisms by which loss of fat mass increases muscle strength and quality.

Estimating the probability of radiographic osteoarthritis in the older patient with knee pain

OBJECTIVE

To determine whether clinical information can practically rule in or rule out the presence of radiographic osteoarthritis in older adults with knee pain.

METHODS

We conducted a cross-sectional diagnostic study involving 695 adults ages >/=50 years reporting knee pain within the last year identified by postal survey and attending a research clinic. Potential indicators of radiographic osteoarthritis were gathered by self-complete questionnaires, clinical interview, and physical examination. Participants underwent plain radiography (posteroanterior, skyline, and lateral views). Radiographic osteoarthritis was defined as the presence of definite osteophytes in at least 1 joint compartment of the index knee.

RESULTS

Independent predictors of radiographic osteoarthritis were age, sex, body mass index, absence of whole leg pain, traumatic onset, difficulty descending stairs, palpable effusion, fixed-flexion deformity, restricted-flexion range of motion, and crepitus. Using this model, 245 participants had a predicted probability >/=80% (practical rule in), of whom 231 (94%) actually had radiographic osteoarthritis (specificity 93%). Twenty-one participants had a predicted probability <20% (practical rule out), of whom only 2 (10%) had radiographic osteoarthritis (sensitivity 99.6%). The predicted probability of radiographic osteoarthritis for the remaining 429 participants fell into an intermediate category (20-79%).

CONCLUSION

Simple clinical information can be used to estimate the probability of radiographic osteoarthritis in individual patients. However, for the majority of community-dwelling older adults with knee pain this method enables the presence of radiographic osteoarthritis to be neither confidently ruled in nor ruled out. Prospective validation and updating of these findings in an independent sample is required.

Obesity and knee arthroplasty

Obesity has been shown to be a risk factor for knee osteoarthritis. Total knee arthroplasty in the obese patient has given rise to some controversy in terms of perioperative risks, and the longevity of the implants. We reviewed the salient literature on this subject regarding the impact of obesity on the knee, the outcome of TKA in the obese patient, and on the effect of TKA on pre-existing obesity. While increased risk of complications and early implant failure has been shown by some studies in the morbidly obese, there is no definite cut-off in Body Mass Index which accurately separates high-risk from low-risk individuals, although there is evidence that heavier patients are at greater risk. We have seen that although postoperative scores are lower in the obese group, these patients may derive considerable improvement in pain following TKA. While not condoning the obese patient with knee arthritis being denied an effective pain-relieving procedure, we stress the importance of appropriate risk-counselling of these patients, and allowance within the healthcare system for the extra financial and service implications placed by the obese TKA patient.

The prevalence of person-perceived participation restriction in community-dwelling older adults

OBJECTIVE

To estimate the prevalence, nature and distribution of person-perceived participation restriction, in community-dwelling older adults.

METHOD

Population based cross-sectional postal survey of 11,055 adults aged 50 years and over in North Staffordshire, United Kingdom. Person-perceived participation restriction was measured using the Keele Assessment of Participation which covers 11 different aspects of life mapped to the World Health Organization's International Classification of Functioning. Four-week period prevalence was calculated for restriction in any, multiple and for each aspect separately. Prevalence estimates were calculated for the total sample, and for each age and gender stratum.

RESULTS

A total of 7,878 subjects responded (adjusted response--71.3%). The 4-week period prevalence of any participation restriction was 51.8%; 3.3% had substantial restriction. Participation restriction increased with age (p<0.001) and, for moderate and substantial restriction, was more frequent in women. The prevalence of restricted participation in individual aspects of life ranged from 3.8% (work) to 25.9% (mobility outside the home).

CONCLUSION

Some restriction of participation 'as and when we want it' is common in the general population and increases with age, although severe restriction only affects a minority. The distribution of person-perceived participation restriction is similar to that of impairments and activity limitation in community-dwelling older adults.

Musculoskeletal disorders associated with obesity: a biomechanical perspective

Despite the multifactorial nature of musculoskeletal disease, obesity consistently emerges as a key and potentially modifiable risk factor in the onset and progression of musculoskeletal conditions of the hip, knee, ankle, foot and shoulder. To date, the majority of research has focused on the impact of obesity on bone and joint disorders, such as the risk of fracture and osteoarthritis. However, emerging evidence indicates that obesity may also have a profound effect on soft-tissue structures, such as tendon, fascia and cartilage. Although the mechanism remains unclear, the functional and structural limitations imposed by the additional loading of the locomotor system in obesity have been almost universally accepted to produce aberrant mechanics during locomotor tasks, thereby unduly raising stress within connective-tissue structures and the potential for musculoskeletal injury. While such mechanical theories abound, there is surprisingly little scientific evidence directly linking musculoskeletal injury to altered biomechanics in the obese. For the most part, even the biomechanical effects of obesity on the locomotor system remain unknown. Given the global increase in obesity and the rapid rise in musculoskeletal disorders, there is a need to determine the physical consequences of continued repetitive loading of major structures of the locomotor system in the obese and to establish how obesity may interact with other factors to potentially increase the risk of musculoskeletal disease.

Contribution of runt-related transcription factor 2 to the pathogenesis of osteoarthritis in mice after induction of knee joint instability

OBJECTIVE

By producing instability in mouse knee joints, we attempted to determine the involvement of runt-related transcription factor 2 (RUNX-2), which is required for chondrocyte hypertrophy, in the development of osteoarthritis (OA).

METHODS

An experimental mouse OA model was created by surgical transection of the medial collateral ligament and resection of the medial meniscus of the knee joints of heterozygous RUNX-2-deficient (Runx2+/-) mice and wild-type littermates. Cartilage destruction and osteophyte formation in the medial tibial cartilage were compared by histologic and radiographic analyses. Localization of type X collagen and matrix metalloproteinase 13 (MMP-13) was examined by immunohistochemistry. Localization of RUNX-2 was determined by X-Gal staining in heterozygous RUNX-2-deficient mice with the lacZ gene insertion at the Runx2-deletion site (Runx2+/lacZ). Messenger RNA levels of type X collagen, MMP-13, and RUNX-2 were examined by real-time reverse transcriptase-polymerase chain reaction analysis.

RESULTS

RUNX-2 was induced in the articular cartilage of wild-type mice at the early stage of OA, almost simultaneously with type X collagen but earlier than MMP-13. Runx2+/- and Runx2+/lacZ mice showed normal skeletal development and articular cartilage; however, after induction of knee joint instability, they exhibited decreased cartilage destruction and osteophyte formation, along with reduced type X collagen and MMP-13 expression, as compared with wild-type mice.

CONCLUSION

RUNX-2 contributes to the pathogenesis of OA through chondrocyte hypertrophy and matrix breakdown after the induction of joint instability.

Distinct association of gene polymorphisms of estrogen receptor and vitamin D receptor with lumbar spondylosis in post-menopausal women

Contribution of genetic backgrounds to the etiology of lumbar spondylosis has been suggested by epidemiological studies. This study was designed to determine the association of restriction fragment length polymorphisms (RFLPs) of estrogen receptor (ER), vitamin D receptor (VDR), parathyroid hormone (PTH) and interleukin-1beta (IL-1beta) genes with the radiological severity of lumbar spondylosis at the disk level from L1/2 to L5/S1 in Japanese post-menopausal women. ER and VDR RFLP haplotypes were associated with the severity of spondylosis in the upper levels (L1/2 and L2/3) more than in the lower levels. Association of ER genotype was more pronounced in the group younger than average than in the older group, while that of VDR genotype was more significant in the older group. Neither PTH nor IL1-beta RFLP was associated with the severity at any levels in either stratified group. We thus conclude that ER and VDR genes may contribute to lumbar spondylosis in a distinct manner: estrogen sensitivity influences the severity in the early phase after menopause while vitamin D plays an important role at older ages when the contribution of estrogen loss is weaker.