The natural history of disability and its determinants in adults with lower limb musculoskeletal pain

Angioembolization in the management of joint pain: current concepts

Joint pain is a common complaint owing to its origin in inflammatory and degenerative joint diseases. Recent research has helped narrow down inadequate angiogenesis as one of the causes. Angioembolization has emerged as a treatment option for this condition when it is refractory to conservative treatment. This review describes angioembolization by elaborating on the mechanism, safety, efficacy, comparative analysis of treatment and the road ahead, in addition to summarizing the existing data on this treatment. The inferences from this review further consolidate transcatheter arterial embolization as one of the prime options for managing joint pain when it is refractory to conservative treatment and label it as one of the most exciting prospects. A limitation of this review is that most of the data were from open label case series or case reports.

Maximal daily stepping cadence partially explains functional capacity of individuals with end-stage knee osteoarthritis

BACKGROUND

Individuals with end-stage knee osteoarthritis (OA) walk at a lower intensity (ie, slower step cadence) contributing to worse physical function. Previous literature reports daily step counts and sedentary time, with little information regarding stepping bouts or cadence. Determining relationships between daily higher stepping cadence duration and clinical outcomes can move the field toward optimal daily stepping prescription.

OBJECTIVE

To quantify daily physical activity patterns of individuals with end-stage knee OA and determine the contribution of high stepping cadence to explain functional capacity variability.

DESIGN

Cross-sectional analysis.

SETTING

Veterans Administration medical center.

PARTICIPANTS

U.S. military veterans (n = 104; age: 67.1 years [7.2]; mean [SD]; male [89.3%]) with end-stage knee OA were enrolled.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURE

Functional capacity (6-Minute Walk Test [6MWT]). Physical activity (activPAL wearable sensor; cadence and time sitting, standing, and stepping), pain (Western Ontario and McMaster Universities Osteoarthritis Index-pain subscale) sociodemographic variables, and comorbidities (body mass index and Functional Comorbidity Index) are the main explanatory variables.

RESULTS

Participants' wake time was mainly sitting (11.0 h/day) in ≥60-minute bouts (29.7% ± 12.7 of sitting time). Standing (3.4 hours/day) and stepping (1.4 h/day) primarily occurred in 0-5 minute bouts (standing: 87.7% ± 14.4 of standing time, stepping: 98.7% ± 12.7 of stepping time) and stepping cadence was predominantly incidental (1-19 spm; 52.9% ± 9.6 of total stepping time). Backward elimination model results indicated shorter medium-to-brisk cadence bout duration, older age, and higher pain significantly explained shorter 6MWT distance (AdjR2=0.24, p < .01).

CONCLUSIONS

Individuals with knee OA spend most of their waking hours sitting, while standing and stepping occurs in short bouts at very low stepping cadence. Decreased time in high stepping cadence is associated with lower functional capacity. Future studies should explore if increasing the daily time spent in higher step cadence can improve functional capacity in this population.

Development and feasibility of a function-based preventive intervention for lifestyle-related disorders

BACKGROUND

The enormous effect of lifestyle-related disorders on health of the global population warrants the development of preventive interventions. Focusing on musculoskeletal health and physical activity may be a way to encourage necessary lifestyle changes by making them more concrete and understandable. The aims of the current study were to develop a function-based preventive intervention aimed at lifestyle-related disorders in physically inactive 40-year-old people and to investigate the feasibility of the intervention. The feasibility study aimed to solve practical and logistical challenges and to develop the intervention based on the experiences of participants and involved clinical personnel according to defined criteria.

METHODS

Development of the standardised functional examination was based on literature-validated tests and clinical reasoning. Development of a risk profile was based on the functional examination and similar profiles which have already proved feasible. The feasibility of the functional examination and risk profile, together with function-based lifestyle counselling was tested on 27 participants in a pilot study with two physiotherapist examinations over a four-month period. Practical results and feedback from participants and collaborating personnel were examined.

RESULTS

The functional examination consists of 20 established tests not requiring specialised equipment or training which were deemed relevant for a middle-aged population and a sub-maximal ergometer test. The risk profile consists of seven functional dimensions: cardiovascular fitness, strength in upper extremity, lower extremity and trunk, mobility, balance and posture, and three non-functional dimensions: weight, self-assessed physical activity and pain. Each dimension contains at least two measures. The participants appreciated the intervention and found it motivating for making lifestyle changes. They found the tests and risk profile understandable and could see them as tools to help achieve concrete goals. The examination required 60-75 min for one physiotherapist. The recruitment rate was low and recruited participants were highly motivated to making lifestyle changes.

CONCLUSION

This project developed a functional test battery and risk profile aimed at inactive 40-year-olds which fulfilled our feasibility criteria. Functional screening and lifestyle counselling were found to be of value to a sub-group of inactive 40-year-olds who were already motivated to improve their health situations.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT05535296 first posted on 10/09/2022.

Obesity and the risk of multiple or severe frequent knee pain episodes: a 4-year follow-up of the ELSA-Brasil MSK cohort

BACKGROUND/OBJECTIVE

Knee pain is an important health problem due to its high prevalence, negative impact on daily activities and quality of life, and societal burden. While the link between excess weight and knee pain has been well-documented in the literature, many studies are limited to patients with osteoarthritis or use cross-sectional data. This longitudinal study investigated whether overweight and obesity were associated with the frequency and severity of frequent knee pain (FKP) episodes over 4 years in civil servants enrolled in the ELSA-Brasil MSK cohort.

METHODS

Knee pain was assessed during baseline face-to-face interviews (2012-2014) and four yearly telephone follow-ups (2015-2019). Disabling FKP episodes or those of moderate to very severe intensity were classified as severe. Multinomial logistic regression models adjusted for confounders were used to test for associations in two participant groups: those with knee pain at baseline (prognosis cohort) and those without knee pain (incidence cohort).

RESULTS

A total of 2644 participants were included: 54.2% female, mean age 55.8 (SD 8.8) years. In the incidence cohort (n = 1896), obesity increased the risk of one (OR: 1.63; 95% CI 1.13-2.37) and multiple FKP episodes (OR: 2.61; 95% CI 1.71-3.97), as well as the risk of non-severe (OR: 1.72; 95% CI 1.04-2.84) and severe FKP episodes (OR: 2.10; 95% CI 1.50-2.95). In the prognosis cohort (n = 748), obesity increased the risk of multiple (OR: 2.54; 95% CI 1.60-4.05) and severe FKP episodes (OR: 2.31; 95% CI 1.49-3.59). Overweight presented the same trends but fell short of significance.

CONCLUSIONS

These results provide further support that overweight and obesity are important contributors to the incidence and worsening of FKP, and that weight management must be prioritized in multidisciplinary knee pain prevention and treatment programs to reduce the burden of musculoskeletal disorders.

Comparison of Joint Mobilization and Movement Pattern Training for Patients With Hip-Related Groin Pain: A Pilot Randomized Clinical Trial

OBJECTIVE

The objective of this study was to assess the feasibility of completing a randomized clinical trial (RCT) and examine the preliminary effects of 2 interventions for hip-related groin pain (HRGP).

METHODS

In this pilot RCT, patients with HRGP, who were 18 to 40 years old, were randomized (1:1 ratio) to a joint mobilization (JtMob) group or a movement pattern training (MoveTrain) group. Both treatments included 10 supervised sessions and a home exercise program. The goal of JtMob was to reduce pain and improve mobility through peripherally and centrally mediated pain mechanisms. The key element was physical therapist-provided JtMob. The goal of MoveTrain was to reduce hip joint stresses by optimizing the biomechanics of patient-specific tasks. The key element was task-specific instruction to correct abnormal movement patterns displayed during tasks. Primary outcomes were related to future trial feasibility. The primary effectiveness outcome was the Hip Disability and Osteoarthritis Outcome Score. Examiners were blinded to group; patients and treatment providers were not. Data collected at baseline and immediately after treatment were analyzed with analysis of covariance using a generalized linear model in which change was the dependent variable and baseline was the covariate. The study was modified due to the coronavirus disease 2019 (COVID-19) pandemic.

RESULTS

The COVID-19 pandemic affected participation; 127 patients were screened, 33 were randomized (18 to the JtMob group and 15 to the MoveTrain group), and 29 (88%) provided posttreatment data. Treatment session adherence was 85%, and home exercise program component adherence ranged from 71 to 86%. Both groups demonstrated significant mean within-group improvements of ≥5 points on Hip Disability and Osteoarthritis Outcome Score scales. There were no between-group differences in effectiveness outcomes.

CONCLUSIONS

A large RCT to assess the effects of JtMob and MoveTrain for patients with HRGP may be feasible. Preliminary findings suggested that JtMob or MoveTrain may result in improvements in patient-reported pain and activity limitations.

IMPACT

The COVID-19 pandemic interfered with participation, but a randomized controlled trial may be feasible. Modification may be needed if the trial is completed during future pandemics.

A nomogram based on radiological features of MRI for predicting the risk of severe pain in patients with osteoarthritis of the knee

Methods

This study aimed to develop and validate a nomogram for predicting the risk of severe pain in patients with knee osteoarthritis. A total of 150 patients with knee osteoarthritis were enrolled from our hospital, and nomogram was established through a validation cohort (n = 150). An internal validation cohort (n = 64) was applied to validate the model.

Results

Eight important variables were identified using the Least absolute shrinkage and selection operator (LASSO) and then a nomogram was developed by Logistics regression analysis. The accuracy of the nomogram was determined based on the C-index, calibration plots, and Receiver Operating Characteristic (ROC) curves. Decision curves were plotted to assess the benefits of the nomogram in clinical decision-making. Several variables were employed to predict severe pain in knee osteoarthritis, including sex, age, height, body mass index (BMI), affected side, Kellgren-Lawrance (K-L) degree, pain during walking, pain going up and down stairs, pain sitting or lying down, pain standing, pain sleeping, cartilage score, Bone marrow lesion (BML) score, synovitis score, patellofemoral synovitis, bone wear score, patellofemoral bone wear, and bone wear scores. The LASSO regression results showed that BMI, affected side, duration of knee osteoarthritis, meniscus score, meniscus displacement, BML score, synovitis score, and bone wear score were the most significant risk factors predicting severe pain.

Conclusions

Based on the eight factors, a nomogram model was developed. The C-index of the model was 0.892 (95% CI: 0.839-0.945), and the C-index of the internal validation was 0.822 (95% CI: 0.722-0.922). Analysis of the ROC curve of the nomogram showed that the nomogram had high accuracy in predicting the occurrence of severe pain [Area Under the Curve (AUC) = 0.892] in patients with knee osteoarthritis (KOA). The calibration curves showed that the prediction model was highly consistent. Decision curve analysis (DCA) showed a higher net benefit for decision-making using the developed nomogram, especially in the >0.1 and <0.86 threshold probability intervals. These findings demonstrate that the nomogram can predict patient prognosis and guide personalized treatment.

Outpatient Service Use in Korean Older Adult Women with Degenerative Arthritis Based on Andersen's Model

To ensure that older adults (aged 65 years or older) can experience a healthy life, they should use medical services that are appropriate, both quantitatively and qualitatively. This study aimed to identify the factors affecting outpatient service use by older adult women with degenerative arthritis using Andersen’s model. A survey was conducted among 232 older adult women with degenerative arthritis in two university hospitals in Seoul. The Korean Activities of Daily Living, Korean Instrumental Activities of Daily Living, and the Geriatric Depression Scale Short Form were used. Data were analyzed using descriptive statistics, χ2-test, t-test, and multiple logistic regression analysis. Among the participants, 69.8% used outpatient services and 30.2% did not. In the univariate analyses, age, marital status, residency, household income, chronic diseases, subjective health status, and disability were significant. Age (odds ratio [OR] = 5.53, p < 0.001), annual household income (OR = 5.64, p < 0.001), chronic diseases (OR = 11.06, p < 0.001), and disability (OR = 3.56, p = 0.016) significantly affected outpatient service use. The results suggest that health promotion interventions for Korean older adult women should focus on predicting outpatient service use according to the patient’s characteristics.

Effects of Aquatic Exercises for Patients with Osteoarthritis: Systematic Review with Meta-Analysis

This systematic review examined papers published in Korean, English and newer publications that were not included in previous studies to assess the effect size of aquatic exercise-based interventions on pain, quality of life and joint dysfunction among patients with osteoarthritis. Six national and international databases were used to review literature (published up to 7 March 2019) on randomized controlled trials of aquatic exercise-based interventions in patients with osteoarthritis. For the 20 studies included, a meta-analysis showed that aquatic exercise produces 0.61-point reduction (n = 756; mean difference (MD) = −0.61; 95% confidence interval (CI): −0.90–−0.32) in pain compared with a control group, and aquatic exercise was effective in reducing pain (n = 315; MD = −0.28; 95% CI: −0.50–−0.05) compared with a land-based exercise group. Another meta-analysis showed that aquatic exercise produces 0.77-point improvement in quality of life (n = 279; MD = −0.77; 95% CI: −1.38–−0.15) compared with a control group. Finally, a meta-analysis showed that aquatic exercise produces 0.34-point reduction in joint dysfunction (n = 279; MD = −0.77; 95% CI: −1.38–−0.15) compared with a control group. For patients with osteoarthritis, aquatic-exercise-based interventions are effective for reducing pain and joint dysfunction and improving quality of life.

The association of socio-economic and psychological factors with limitations in day-to-day activity over 7 years in newly diagnosed osteoarthritis patients

Previous research has established links between chronic pain and impaired cognitive ability, as well as between chronic pain and anxiety, in osteoarthritis. Furthermore, there is evidence linking risk of osteoarthritis to lower educational attainment. However, the inter-play of these factors with key social factors (e.g., social deprivation) at the early stages of osteoarthritis are not understood. Here, we used data from waves 4, 5, 6 and 7 of the Survey of Health, Ageing and Retirement in Europe (SHARE) (n = 971) and selected a subsample of respondents who initially did not report a diagnosis of osteoarthritis until wave 6. We used path models to test how social deprivation, education and anxiety, before diagnosis (waves 4 and 5), affect the relationship between cognitive ability, pain and limitations in activities of daily living following diagnosis (waves 6 and 7). We show that high social deprivation before diagnosis predicts greater limitations in activities of daily living after diagnosis, with this effect partly mediated by impaired cognitive ability. We also find that higher educational attainment before diagnosis may protect against limitations in activities of daily living after diagnosis via better cognitive ability and lower anxiety. Therefore, improving cognitive ability and managing anxiety may mitigate the associations of social deprivation and low educational attainment with limitations in activities of daily living.

Different Components of Subjective Well-being Are Associated With Chronic Nondisabling and Disabling Knee Pain: ELSA-Brasil Musculoskeletal Cohort

BACKGROUND/OBJECTIVE

Chronic knee pain (CKP) is a common pain complaint in older adults that is often associated with disability. This study investigated the relationship between 2 components of subjective well-being (depressive symptoms and life satisfaction) and CKP phenotypes based on the presence of knee disability.

METHODS

A cross-sectional study was performed at baseline of ELSA-Brasil Musculoskeletal cohort (2012-2014). Chronic knee pain phenotypes were identified according to the presence of CKP that was accompanied or not by disability, which was assessed by a question on pain-related limitations to perform everyday activities (overall), Western Ontario and McMaster Universities Osteoarthritis Index's physical function subscale (daily tasks) and 5-times sit-to-stand test (objective). Depressive symptoms were assessed by the Clinical Interview Schedule-Revised and life satisfaction by the Satisfaction With Life Scale. Multinomial logistic regressions used CKP phenotypes as response variables (no CKP as reference).

RESULTS

The sample comprised 2898 participants (mean age, 55.9 ± 8.9 years; 52.9% were female). After adjustments for sociodemographic and clinical factors, depressive symptoms were associated with daily tasks disabling CKP (odds ratio [OR], 2.30; 95% confidence interval [CI], 1.45-3.66) and objective disabling CKP (OR, 1.95; 95% CI, 1.29-2.93) and with nondisabling CKP for the overall disability measure (OR, 1.54; 95% CI, 1.17-2.04). Life satisfaction was inversely associated with all phenotypes in fully adjusted models, with strongest magnitude of associations observed for disabling CKP.

CONCLUSIONS

The association of depressive symptoms and life satisfaction with CKP phenotypes suggest the need to address both negative and positive components of subjective well-being in the assessment of individuals with knee complaints.

The Effect of Local Heat Therapy versus Cold Rub Gel on Pain and Joint Functions in Patients with Knee Osteoarthritis

This study was compared the effect of local heat therapy versus cold rub gel on pain and joint function in patients with knee osteoarthritis. One hundred seventeen patients with knee osteoarthritis were randomly assigned to cold rub gel, local heat therapy, and control group. Data were collected by knee injury and osteoarthritis outcome score at a week prior to the interventions and on weeks of 1, 2, 3, and 4 of the interventions. A significant difference was found between the three groups in terms of pain severity (p = .001), joint symptoms (p = .001), ADL function (p = .001), Sport and Recreation function (p = .001), except Knee related QOL (p = .3). Cold rub gel and heat therapy were both effective in improving pain and joint function in patients with knee osteoarthritis.

Postoperative Bone Marrow Lesions (BMLs) Are Associated with Pain Severity in Patients Undergoing Open Wedge High Tibial Osteotomy (OWHTO)

The purpose of the study was to investigate the relationship between postoperative bone marrow lesions (BMLs) and pain severity in patients undergoing open wedge high tibial osteotomy (OWHTO). We reviewed the patients undergoing OWHTO between April 2018 and April 2020. The demographic and clinical data of patients were collected. Clinically, VAS and Knee injury and Osteoarthritis Outcome Score (KOOS) were used to assess pain level and functional outcomes of patients. The MRI Osteoarthritis Knee Score (MOAKS) was used to assess the total BMLs size in medial tibiofemoral (MTF), lateral tibiofemoral (LTF), and patellofemoral (PF) joints. 98 patients were enrolled in the study, including 57 male and 41 female patients. The VAS scores improved significantly from 6.1 ± 0.8 to 1.5 ± 0.9 (p < 0.001), and all subscales of KOOS improved significantly after surgery (p < 0.001). There were no significant differences between the pre- and postoperative total BML size of PF and LTF joints (p > 0.05). We observed significant improvements in the total BML size of MTF joint (p < 0.001). The VAS scores and KOOS pain scores improved better in patients without postoperative MTF joint BMLs (p < 0.001). Postoperative MTF joint BMLs were correlated with postoperative VAS (p < 0.001) and KOOS pain (p < 0.001). Our study demonstrates that MTF joint BMLs improved significantly after OWTHO. We confirmed that the presence of postoperative MTF joint BMLs are strongly associated with pain severity. The greater the improvement in postoperative MTF joint BMLs, the less pain. Our findings provide valuable understandings of OWHTO in the treatment of knee osteoarthritis (KOA) and potential future directions for KOA treatment approaches.

Association of Sports Participation With Osteoarthritis: A Systematic Review and Meta-Analysis

Background:

The association between participating in sport and osteoarthritis is not fully understood.

Purpose:

To investigate the association between osteoarthritis and participating in sports not listed in previous reviews: American football, archery, baseball, bobsleigh, curling, handball, ice hockey, shooting, skeleton, speed skating, and wrestling.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

We searched 4 electronic databases and hand searched recent/in-press editions of relevant journals. The criteria for study selection were case-control studies, cohort studies, nested case-control studies, and randomized trials with a control group that included adults to examine the effect of exposure to any of the included sports on the development of osteoarthritis.

Results:

The search returned 6197 articles after deduplication. Nine studies were included in the final review, covering hip, knee, and ankle osteoarthritis. There were no studies covering archery, baseball, skeleton, speed skating, or curling. The 6 sports included in the review were analyzed as a collective; the results of the meta-analysis indicated that participation in the sports analyzed was associated with an increased risk of developing osteoarthritis of the hip (relative risk [RR] = 1.67 [95% confidence interval (CI), 1.15-2.41]; P = .04), knee (RR = 1.60 [95% CI, 1.23-2.08]; P < .001), and ankle (RR = 7.08 [95% CI, 1.24-40.51]; P = .03) as compared with controls. Meta-analysis suggested a significantly increased likelihood of developing hip osteoarthritis through participating in wrestling (RR = 1.78 [95% CI, 1.20-2.64]; P = .004) and ice hockey (RR = 1.70 [95% CI, 1.27-2.29]; P < .001), while there was no significant difference through participating in handball (RR = 2.50 [95% CI, 0.85-7.36]; P = .10). Likelihood of developing knee osteoarthritis was significantly increased in wrestling (RR = 2.22 [95% CI, 1.59-3.11]) and ice hockey (RR = 1.52 [95% CI, 1.18-1.96]; both P < .002). According to the meta-analysis, shooting did not have a significant effect on the RR of knee osteoarthritis as compared with other sports (RR = 0.43 [95% CI, 0.06-2.99]; P = .39).

Conclusion:

The likelihood of developing hip and knee osteoarthritis was increased for ice hockey and wrestling athletes, and the risk of developing hip osteoarthritis was increased for handball athletes. The study also found that participation in the sports examined, as a collective, resulted in an increased risk of developing hip, knee, and ankle osteoarthritis.

Pain Pharmacotherapy in a Large Cohort of Patients with Osteoarthritis: A Real-World Data Analysis

INTRODUCTION

There is limited evidence on the consumption of analgesics in real-world large cohorts of patients with osteoarthritis (OA), especially in those with comorbidities. We aimed to characterize the use of pharmacological analgesic treatments, evaluate standardized comorbidity rates, and assess treatment trends. Our hypotheses were: (1) OA patients generally consume low and inconsistent pharmacological analgesic treatments; (2) analgesic treatment is often non-congruent with comorbidity-related safety concerns.

METHODS

The study was carried out at the second largest health maintenance organization in Israel. Members aged 18 years or above who were diagnosed with OA before December 31, 2018, were included. Information was obtained from the members' electronic medical record (EMR) including data on dispensed prescriptions, which were used to estimate analgesic consumption.

RESULTS

A total of 180,126 OA patients were included in our analyses; analgesics were dispensed to 64.2% of the patients, with oral NSAIDs and opioids dispensed to 34.1 and 22.9% of the OA population, respectively. Analgesic use increased with time lapsed from OA diagnosis (p < 0.001), up to a median of 59 days covered (IQR, 20-175) after 21 years. Rates of most comorbidities in the OA population were higher compared to the MHS general population. Patients with comorbidities used more NSAIDs and opioids compared to those without them.

CONCLUSIONS

Most OA patients use analgesics, usually oral NSAIDs. Analgesic use remains relatively low throughout the years, indicating that many OA patients are not being treated pharmacologically for pain on a regular basis. Despite having higher rates of several comorbidities compared to MHS general population, many OA patients are still treated with analgesics that can be associated with a worsening in comorbidity.

The role of pain and walking difficulties in shaping willingness to undergo joint surgery for osteoarthritis: Data from the Swedish BOA register

Objectives

To investigate whether the association between pain intensity and willingness to undergo surgery is explained by walking difficulties, in patients with knee or hip osteoarthritis (OA).

Methods

This is an observational study using data from the Better management of patients with Osteoarthritis (BOA) register, which collects data from a publicly financed self-management programme for people with OA in Sweden. We included all patients with knee or hip OA who attended the baseline visit between 2008 and 2016. We conducted separate mediation analyses within a counterfactual framework to estimate the mediation effect of walking difficulties (yes/no) on willingness to undergo surgery (yes/no) for each one-point increase in pain (0-10 on a numeric rating scale), adjusted for relevant confounders.

Results

We included 72,131 patients (69% women, mean age 66, mean pain 5.4, 81% had walking difficulties, 27% was willing to undergo surgery). A one-point increase in pain intensity was associated with 1.53 (95% CI: 1.51; 1.55) higher odds of being willing to undergo surgery. Walking difficulties mediated 10%-25% of the effect of one-point increase in pain when pain was <8/10, while at pain ≥8/10 this percentage decreased to 3%.

Conclusions

More than 80% of the BOA patients have mild to moderate pain (<8/10) and walking difficulties can mediate up to a quarter of the total effect of pain on the willingness to undergo surgery in these patients. Trials to evaluate the potential to lower surgery demand by reducing walking difficulties in people with these characteristics are needed.

Incidence and risk factors for poor ankle functional recovery, and the development and progression of posttraumatic ankle osteoarthritis after significant ankle ligament injury (SALI): the SALI cohort study protocol

Background

Ankle sprains are one of the most common musculoskeletal injuries, accounting for up to 5% of all Emergency Department visits in the United Kingdom. Ankle injury may be associated with future ankle osteoarthritis. Up to 70% of ankle osteoarthritis cases may be associated with previous ankle injury. There is limited research regarding the association between ankle sprain and ankle osteoarthritis development. The current study aims to phenotype those who suffer significant ankle ligament injuries, identify potential risk factors for ankle injuries and subsequent poor recovery, examine why individuals may develop osteoarthritis, and what factors influence this chance.

Methods

In this multicentre cohort study participants were recruited from nine Emergency Departments and two Urgent Care Centres in the United Kingdom. Participants (aged 18–70 years old) were defined as those who had suffered an isolated acute ankle sprain, which was Ottawa Ankle Rules positive, but negative for a significant ankle fracture on x-ray. Age and sex matched controls were also recruited. The controls were individuals who had not suffered a significant ankle injury, including ankle pain, function affected for more than 7 days, or the ankle caused them to report to an Emergency Department. Data is collected through a series of seven questionnaires (at baseline, 3 months, 1 year, 3 years, 5 years, 10 years, and 15 years later). The questionnaires include four sections (demographic questions; index injury, and injury history questions; functional assessment questions; and quality of life questions) and are designed to collect detailed information about the individual, their injury, potential risk factors for ankle sprains and ankle osteoarthritis, plus their medical history and any medication consumed.

Discussion

The Significant Ankle Ligament Injury (SALI) study aims to add to the limited knowledge regarding which factors can predict ankle sprains, complaints, and osteoarthritis. This is important because despite ankle sprains being regarded as a benign injury that resolves quickly, residual symptoms are not uncommon months and years after the injury.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04230-8.

[Efficacy and safety of chondroitin sulfate therapy in patients with knee and hip osteoarthritis]

OBJECTIVE

To evaluate symptom-modifying effects of a two-month parenteral therapy with chondroitin sulfate («Mucosat») in patients with knee and/or hip osteoarthritis (OA) in various combinations of adjuvant therapy.

MATERIAL AND METHODS

There were 70 patients with primary and/or post-traumatic unilateral/bilateral knee and/or hip osteoarthritis (Kellgren-Lawrence grade I-II). Pain syndrome severity was assessed as ≥ 50 mm (100-mm VAS), total Leken's index - ≥ 5 points. The main group comprised 40 patients who received Mucosat for 60 days. NSAIDs were additionally prescribed in 9 (22.5%) of these patients. The control group included 30 patients with intra-articular injection of hyaluronic acid. All patients underwent clinical and functional examination (rating scales VAS, Leken's total index, WOMAC index, EQ-5D health questionnaire), laboratory diagnosis (IL-1, IL-6, TNF-α), X-ray examination, assessment of adverse events at 5 visits.

RESULTS AND CONCLUSION

Administration of chondroitin sulfate is associated with reduced local pain syndrome and functional normalization of musculoskeletal system. Prolonged pain-free period with high safety profile due to reduced need for NSAIDs is an advantage of Mucosat therapy. Thus, this drug may be recommended for initial therapy. A combination of chondroitin sulfate with intra-articular injection of hyaluronic acid may be perspective for optimization of therapy and secondary prevention of exacerbations of OA. Further research is required.

Efficacy and safety of combination of curcuminoid complex and diclofenac versus diclofenac in knee osteoarthritis: A randomized trial

BACKGROUND

To compare the efficacy and safety of combination of curcuminoid complex and diclofenac vs diclofenac alone in the treatment of knee osteoarthritis (OA).

METHODS

In this randomized trial, 140 patients of knee OA received either curcuminoid complex 500 mg (BCM-95) with diclofenac 50 mg 2 times daily or diclofenac 50 mg alone 2 times daily for 28 days. Patients were assessed at baseline, day 14 and day 28. Primary efficacy measures were Knee injury and OA outcome score (KOOS) subscale at day 14 and day 28. Anti-ulcer effect and patient-physician's global assessment of therapy at day 28 were included as secondary endpoints. Safety after treatment was evaluated by recording adverse events and laboratory investigations.

RESULTS

Both treatment groups showed improvement in primary endpoints at each evaluation visit. Patients receiving curcuminoid complex plus diclofenac showed significantly superior improvement in KOOS subscales, viz. pain and quality of life at each study visit (P < .001) when compared to diclofenac. Less number of patients required rescue analgesics in curcuminoid complex plus diclofenac group (3%) compared to diclofenac group (17%). The number of patients who required histamine 2 (H2) blockers was significantly less in curcuminoid complex plus diclofenac group compared to diclofenac group (6% vs 28%, respectively; P < .001). Adverse effects were significantly less in curcuminoid complex plus diclofenac group (13% vs 38% in diclofenac group; P < .001). Patient's and physician's global assessment of therapy favored curcuminoid complex plus diclofenac than diclofenac.

CONCLUSION

Combination of curcuminoid complex and diclofenac showed a greater improvement in pain and functional capacity with better tolerability and could be a better alternative treatment option in symptomatic management of knee OA.

TRIAL REGISTRATION

ISRCTN, ISRCTN10074826.

Association between radiographic anterior cruciate ligament tear and joint symptoms: Data from the osteoarthritis initiative

INTRODUCTION

Symptomatic osteoarthritis (OA) in the knee is defined as the presence of OA radiographic features in combination with knee symptoms. Pain has not been shown to correlate meaningfully to radiographic severity. We aimed to determine the relationship between a tear of the anterior cruciate ligament (ACL) with knee symptoms and radiographic OA.

METHODS

A within-person, between-knee cross-sectional study of 37 participants from the Osteoarthritis Initiative (OAI) with a complete or partial ACL tear detected on magnetic resonance imaging in 1 knee (index knee) were included. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS) and radiographs of both knees, 1 with an ACL tear and one without (control knee) were scored for OA severity (Kellgren-Lawrence Grading) and symptoms. A generalized estimating equation with linear regression was used to compare symptom scores within individuals as well as to radiographic severity.

RESULTS

Thirty-seven individuals (40% female, average age = 60.7years, body mass index = 31.0 kg/m² ) reported no difference in knee symptoms (WOMAC pain odds ratio [OR] =1.92, 95%CI 0.699-5.248, P = .21; KOOS symptoms OR = 2.12, 95%CI 0.740-6.065, P = .09), stiffness (OR = 1.67, 95%CI 0.653-5.583, P = .35) or functional disability (OR = 1 0.97, 95%CI 0.515-7.508, P = .32) in the knee that exhibited an ACL tear compared to the control knee. Only knee function and disability (WOMAC Disability OR = 1.12, 95%CI 1.003-1.249, P = .04) were associated with radiographic severity between index and control knees.

CONCLUSION

Individuals did not report an increase in knee pain, stiffness or disability in their ACL-deficient knee. Only disability was associated with worsening severity of radiographic OA in ACL-deficient knees.

Best Evidence Rehabilitation for Chronic Pain Part 5: Osteoarthritis

Osteoarthritis (OA) is a leading cause of chronic pain and disability in older adults, which most commonly affects the joints of the knee, hip, and hand. To date, there are no established disease modifying interventions that can halt or reverse OA progression. Therefore, treatment is focused on alleviating pain and maintaining or improving physical and psychological function. Rehabilitation is widely recommended as first-line treatment for OA as, in many cases, it is safer and more effective than the best-established pharmacological interventions. In this article, we describe the presentation of OA pain and give an overview of its peripheral and central mechanisms. We then provide a state-of-the-art review of rehabilitation for OA pain—including self-management programs, exercise, weight loss, cognitive behavioral therapy, adjunct therapies, and the use of aids and devices. Next, we explore several promising directions for clinical practice, including novel education strategies to target unhelpful illness and treatment beliefs, methods to enhance the efficacy of exercise interventions, and innovative, brain-directed treatments. Finally, we discuss potential future research in areas, such as treatment adherence and personalized rehabilitation for OA pain.

Safety and efficacy of curcumin versus diclofenac in knee osteoarthritis: a randomized open-label parallel-arm study

Background

The purpose of this study was to compare the efficacy and safety of curcumin with those of diclofenac in the treatment of knee osteoarthritis (OA).

Methods

In this randomized, open-label, parallel, active controlled clinical study, 139 patients with knee OA were randomly assigned to receive either a curcumin 500-mg (BCM-95^®) capsule three times daily or a diclofenac 50-mg tablet two times daily for 28 days. Patients underwent assessment at baseline and days 7, 14, and 28. The main outcome measure was severity of pain using visual analogue scale score at days 14 and 28. Knee Injury and Osteoarthritis Outcome Score (KOOS) (at days 14 and 28), anti-flatulent effect (at day 7), anti-ulcer effect, weight-lowering effect, and patient’s and physician’s global assessment of therapy at day 28 were included as secondary outcome measures. Safety after treatment was evaluated by recording adverse events and laboratory investigation.

Results

At days 14 and 28, patients receiving curcumin showed similar improvement in severity of pain and KOOS scale when compared with diclofenac, and the difference was not statistically significant. At day 7, the patients who received curcumin experienced a significantly greater reduction in the number of episodes of flatulence compared with diclofenac (P <0.01). At day 28, a weight-lowering effect (P <0.01) and anti-ulcer effect (P <0.01) of curcumin were observed. None of the patients required H2 blockers in the curcumin group, and 19 patients required H2 blockers in the diclofenac group (0% versus 28%, respectively; P <0.01). Adverse effects were significantly less in the curcumin group (13% versus 38% in the diclofenac group; P <0.01). Patient’s and physician’s global assessment of therapy was similar in the two treatment groups.

Conclusion

Curcumin has similar efficacy to diclofenac but demonstrated better tolerance among patients with knee OA. Curcumin can be an alternative treatment option in the patients with knee OA who are intolerant to the side effects of non-steroidal anti-inflammatory drugs.

Trial registration

ISRCTN, ISRCTN10074826. Registered 21 November 2017 - Retrospectively registered.

A novel preoperative scoring system for the indication of unicompartmental knee arthroplasty, as predictor of clinical outcome and satisfaction

INTRODUCTION

Proper patient selection is a crucial factor for the outcome of the unicompartmental knee arthroplasty (UKA). However, there is still not a clear consensus on which patients could benefit the utmost from a UKA. The purpose of this prospective study was to introduce a novel, preoperative, predictive score (Unicompartmental Indication Score, UIS) to aid proper patient selection in UKA.

MATERIALS AND METHODS

A total of 152 patients with an average age of 68 years and a mean follow-up of 27 months were evaluated preoperatively with the UIS and postoperative at every follow-up. Correlation analysis was applied to identify potential relationships between the UIS, functional outcomes, pain relief, patient satisfaction, and range of motion. The ROC analysis was used to identify the best cutoff value of the UIS, which would have predicted an optimal outcome following UKA.

RESULTS

The majority of the patients (91%) were satisfied with the operation, with 61% reporting excellent and 30% good satisfaction. The UIS was positively correlated to the postoperative Knee Society Score (KSS) for both pain (r = 0.26, p < 0.001) and function (r = 0.31, p < 0.001). The UIS was also positively correlated to the patient satisfaction (p = 0.46, p < 0.001) and maximum postoperative flexion (r = 0.25, p < 0.001). The ROC analysis provided an ideal cutoff for UIS at 25 points (sensitivity: 75%, sensibility: 93%, area under the curve: 86%). At a mean follow-up of 27 months (range 24-37), we observed three revisions in 152 consecutive UKA with a mean UIS of 27 points (range 20-30).

CONCLUSIONS

The newly introduced UIS score might be a reliable preoperative scoring system to predict patients with excellent satisfaction, functional outcome, pain relief and possibly implant survivorship following UKA, and therefore, could help the proper patient selection and decision-making in UKA.

LEVEL-OF-EVIDENCE

Prospective study, II.

Vascular endothelial growth factor expression and their action in the synovial membranes of patients with painful knee osteoarthritis

BACKGROUND

Research suggests that vascular endothelial growth factor (VEGF) levels in the synovial fluid of knee osteoarthritis (KOA) patients are positively correlated with KOA severity. The relationship between synovial VEGF levels and pain in human KOA patients is not fully understood, and the role of VEGF in the pain pathway remains unclear.

METHODS

We harvested synovial membrane (SM) from 102 patients with radiographic evidence of KOA (unilateral Kellgren/Lawrence [K/L] grade 2-4) during total knee arthroplasty. Patients scored their pain on a 0 to 10 cm visual analog scale (VAS). VEGF levels in the SM of KOA patients with strong/severe (VAS ≥ 6) and mild/moderate pain (VAS < 6) were compared. Correlations between VAS and VEGF mRNA expression were investigated. To investigate a possible mechanism for VEGF-induced pain, the distribution of VEGF and the neuropeptide apelin was determined by immunohistochemical analyses. To investigate the role of VEGF in regulating apelin expression, SM cells were exposed to VEGF.

RESULTS

VEGF expression in the VAS ≥ 6 group was significantly greater than expression in the VAS < 6 group. Expression levels of VEGF were also positively correlated with VAS. VEGF-positive cells were identified in the lining of the SM. Expression of apelin mRNA and protein were significantly elevated in SM cells treated with exogenous VEGF compared to those treated with vehicle.

CONCLUSION

Synovial VEGF may be involved in pain pathways in KOA and its action may be mediated by apelin.

Effect of a low-intensity, self-management lifestyle intervention on knee pain in community-based young to middle-aged rural women: a cluster randomised controlled trial

Background

Knee pain is common with obesity and weight gain being important risk factors. Previous clinical trials have focused on overweight or obese adults with knee pain and osteoarthritis and demonstrated modest effects of intense weight loss programs on reducing knee pain despite very significant weight loss. There has been no lifestyle intervention that targets community-based adults to test its effect on prevention of knee pain. We aimed to determine the effect of a simple low-intensity self-management lifestyle intervention (HeLP-her), proven in randomised controlled trials to improve lifestyle and prevent weight gain, on knee pain in community-based young to middle-aged rural women.

Methods

A 1-year pragmatic, cluster randomised controlled trial was conducted in 649 community-based women (aged 18–50 years) to receive either the HeLP-her program (consisting of one group session, monthly SMS text messages, one phone coaching session, and a program manual) or one general women’s health education session. Secondary analyses were performed in 390 women who had knee pain measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at baseline and 12-month follow-up. “Any knee pain” was defined as a WOMAC pain score ≥ 1. Knee pain worsening was defined as an increase in WOMAC pain score over 12 months.

Results

Thirty-five percent of women had “any knee pain” at baseline. The risk of knee pain worsening did not differ between the intervention and control groups over 12 months. For women with any knee pain at baseline, those in the intervention arm had a lower risk of knee pain worsening compared with those in the control arm (OR 0.37, 95% CI 0.14–1.01, p = 0.05), with a stronger effect observed in women with body mass index ≥ 25 kg/m² (OR 0.28, 95% CI 0.09–0.87, p = 0.03).

Conclusions

In community-based young to middle-aged women, a simple low-intensity lifestyle program reduced the risk of knee pain worsening in those with any knee pain at baseline, particularly in those overweight or obese. Pragmatic lifestyle programs such as HeLP-her may represent a feasible lifestyle intervention to reduce the burden of knee pain in the community.

Trial registration

ACTRN12612000115831, registered 24 January 2012.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1572-5) contains supplementary material, which is available to authorized users.

Effect of frequency on crack growth in articular cartilage

Cracks can occur in the articular cartilage surface due to the mechanical loading of the synovial joint, trauma or wear and tear. However, the propagation of such cracks under different frequencies of loading is unknown. The objective of this study was to determine the effect of frequency of loading on the growth of a pre-existing crack in cartilage specimens subjected to cyclic tensile strain. A 2.26 mm crack was introduced into cartilage specimens and crack growth was achieved by applying a sinusoidally varying tensile strain at frequencies of 1, 10 and 100 Hz (i.e. corresponding to normal, above normal and up to rapid heel-strike rise times, respectively). These frequencies were applied with a strain of between 10–20% and the crack length was measured at 0, 20, 50, 100, 500, 1000, 5000 and 10,000 cycles of strain. Crack growth increased with increasing number of cycles. The maximum crack growth was 0.6 ± 0.3 (mean ± standard deviation), 0.8 ± 0.2 and 1.1 ± 0.4 mm at frequencies of 1, 10 and 100 Hz, respectively following 10,000 cycles. Mean crack growth were 0.3 ± 0.2 and 0.4 ± 0.2 at frequencies of 1 and 10 Hz, respectively. However, this value increased up to 0.6 ± 0.4 mm at a frequency of 100 Hz. This study demonstrates that crack growth was greater at higher frequencies. The findings of this study may have implications in the early onset of osteoarthritis. This is because rapid heel-strike rise times have been implicated in the early onset of osteoarthritis.

Mental Health and Pain in Older Adults: Findings from Urban HEART-2

Pain is an important component of disability problems, and plays a key role in mental health of older adults. This study aims to investigate the relationship between mental health and pain in older adults of Tehran, Iran. This was a cross-sectional study using data on 5326 older adults aged ≥60 years old from a large population-based survey (Urban HEART-2). A multistage cluster random sampling method was used to select the participants in Tehran, Iran, in 2011. General Health Questionnaire (GHQ-28), pain questionnaire, and socioeconomic questionnaires were used to collect the data. A total of 5326 older adults, 3811 (71.6%) married and 2797 (52.5%) female, were included into the study. The mean age of the participants was 68.92 ± 7.02 years. Mean of GHQ-28 scores in the sample was 51.08 ± 10.94, which indicates of a good level of mental health. The majority of the older adults had knee and back pain (more than 50%). Regardless of the chronicity, time, and the mode of reaction to it, knee and back pain were the highly reported pains among the participants. There was a statistically significant difference between two groups of older adults, with and without pain, in terms of GHQ-28 scores. Multiple regression analysis revealed that there was a relationship between mental health and the following factors: pain in head, shoulder, teeth, upper and lower limbs, education, gender, age, and marital status. Whatever the explanation, the relation of lowered health status to pain in all body parts among older people is considerable. This renders this matter as a top priority in health policy making.

Body Pain Intensity and Interference in Adults (45-53 Years Old): A Cross-Sectional Survey in Chongqing, China

Culture and national care models matter both in reporting and treatment of pain status. However, most findings on body pain intensity and interference in adults are from Western studies, with little reliable evidence from China. This study aimed to assess body pain intensity and interference and its associations with demographic, socioeconomic characteristics, and health behaviors in adults. A cross-sectional survey was performed to collect data from 1224 adults, who were recruited via multistage stratified random sampling. The SF-36 quality-of-life instrument was used to investigate body pain intensity and interference. Ordinal logistic regression analysis was used in this study. Our results showed that 64.1% of the participants (males: 687; females: 537) reported body pain, and 45.7% of the participants reported body pain interference. Middle-aged respondents who were female, were unmarried/divorced or separated/widowed, had a negative relationship with their family, had poor sleep quality, and were not satisfied with their current living conditions had a higher body pain intensity rating (ordered logistic regression/six-level pain intensity criterion; odds ratios, p < 0.05). Respondents who were unmarried/divorced or separated/widowed, with a low education level, were unemployed, had lower incomes, had a negative relationship with their family, and were not satisfied with their current living conditions had a higher body pain interference rating (ordered logistic regression/five-level pain interference criterion; odds ratios, p < 0.05). In conclusion, an estimated 64.1% of middle-aged adults reported body pain, and 45.7% of middle-aged adults reported body pain interference. These results provide a clue for possible interventions for improving body pain intensity and interference in adults, especially among middle-aged people. These factors should be taken into consideration in the prevention of pain, pain management and treatment planning in order to help relieve the stress of pain among adults.

Risk factors for lumbar intervertebral disc height narrowing: a population-based longitudinal study in the elderly

BACKGROUND

The progression of disc degeneration is generally believed to be associated with low back pain and/or degenerative lumbar diseases, especially in the elderly. The purpose of this study was to quantitatively evaluate changes in lumbar disc height using radiographic measurements and to investigate risk factors for development of disc height narrowing of the elderly.

METHODS

From 1997 to 2007, 197 village inhabitants at least 65 years-old who participated in baseline examinations and more than four follow-up examinations conducted every second year were chosen as subjects for this study. Using lateral lumbar spine radiographs of each subject, L1-L2 to L5-S1 disc heights were measured. The subjects were divided into two groups according to the rate of change in disc height: mildly decreased (≤20 % decrease) and severely decreased (>20 % decrease). A stepwise multiple logistic regression analysis was used to select those factors significantly associated with disc height narrowing.

RESULTS

Disc height at each intervertebral disc (IVD) level decreased gradually over ten years (p < 0.01, an average 5.8 % decrease of all disc levels). There was no significant difference in the rate of change in disc height among the IVD levels. Female gender, radiographic knee osteoarthritis and low back pain at baseline were associated with increased risk for disc height narrowing.

CONCLUSIONS

We conducted the first population-based cohort study of the elderly that quantitatively evaluated lumbar disc height using radiographic measurements. The risk factors identified in this study would contribute to a further understanding the pathology of disc degeneration.

Web-Based Study of Risk Factors for Pain Exacerbation in Osteoarthritis of the Knee (SPARK-Web): Design and Rationale

Background

Knee osteoarthritis (OA) is the most frequent cause of limited mobility and diminished quality of life. Pain is the main symptom that drives individuals with knee OA to seek medical care and a recognized antecedent to disability and eventually joint replacement. Many persons with symptomatic knee OA experience recurrent pain exacerbations. Knowledge and clarification of risk factors for pain exacerbation may allow those affected to minimize reoccurrence of these episodes.

Objective

The aim of this study is to use a Web-based case-crossover design to identify risk factors for knee pain exacerbations in persons with symptomatic knee OA.

Methods

Web-based case-crossover design is used to study persons with symptomatic knee OA. Participants with knee pain and radiographic knee OA will be recruited and followed for 90 days. Participants will complete an online questionnaire at the baseline and every 10 days thereafter (totaling up to 10 control-period questionnaires); participants will also be asked to report online when they experience an episode of increased knee pain. Pain exacerbation will be defined as an increase in knee pain severity of two points from baseline on a numeric rating scale (NRS 0-10). Physical activity, footwear, knee injury, medication use, climate, psychological factors, and their possible interactions will be assessed as potential triggers for pain exacerbation using conditional logistic regression models.

Results

This project has been funded by the National Health and Medical Research Council (NHMRC). The enrollment for the study has started. So far, 343 participants have been enrolled. The study is expected to be finished in October 2015.

Conclusions

This study will identify risk factors for pain exacerbations in knee OA. The identification and possible modification/elimination of such risk factors will help to prevent the reoccurrence of pain exacerbation episodes and therefore improve knee OA management.

Prevalence and correlates of pain interference in older adults: why treating the whole body and mind is necessary

Our study presents pain-related interference rates in a sample of community-dwelling, older adults and determines factors associated with these restrictions. Participants were 9506 respondents to the Biopsychosocial Religion and Health Study (66.8% female and 33.2% male; average age = 62.3 years). In this sample, 48.2% reported no pain-related interference, whereas 37.7% reported moderate and 14.1% reported severe interference. As hypothesized, older age, female gender, lower education, financial strain, traumatic experiences, worse health, increased body mass index, poor sleep, and depressive symptoms all were associated with higher pain interference ratings (ordered logistic regression/three-level pain criterion; odds ratios p < 0.05). Our findings are similar to those from younger adults, and they suggest enduring effects of trauma on health and reveal the complexity of chronic pain in community-dwelling, older adults.

Relationships among foot position, lower limb alignment, and knee adduction moment in patients with degenerative knee osteoarthritis

[Purpose] The aim of this study was to determine the relationships among the foot progression angle, foot rotation angle, lower limb alignment, and knee adduction moments in patients with degenerative knee osteoarthritis (OA). [Subjects] Forty-eight patients diagnosed with degenerative knee OA (Kellgren-Lawrence grades 2 and 3) were included. [Methods] To assess the lower extremity alignment and weight-bearing ratio, static radiographic measurement was used. Foot progression angle, foot rotation angle, and knee adduction moments were measured by using a three-dimensional motion analysis system. [Results] The results of this study were as follows: the foot progression angle in the early and late stance phase was significantly correlated with the first and second peak knee adduction moments; the weight-bearing ratio was significantly correlated with the first and second peak knee adduction moments; and the tibiofemoral angle was significantly correlated with the first and second peak knee adduction moments. [Conclusion] The results of the present study indicated that as the foot progression angle and the foot lateral rotation angle increased, the knee adduction moment decreased. The weight-bearing ratio and tibiofemoral angle assessment with mechanical axis alignment were correlated with the knee adduction moments. These parameters may be helpful for selecting therapeutic options for patients with degenerative knee OA.

Independent associations of socioeconomic factors with disability and pain in adults with knee osteoarthritis

BACKGROUND

The purpose of this study is to explore the relationship between function, pain and stiffness outcomes with individual and community socioeconomic status (SES) measures among individuals with radiographic knee osteoarthritis (rOA).

METHODS

Cross-sectional data from the Johnston County Osteoarthritis Project were analyzed for adults age 45 and older with knee rOA (n = 782) and a subset with both radiographic and symptomatic knee OA (n = 471). Function, pain and stiffness were measured using the Western Ontario and McMasters Universities Index of Osteoarthritis (WOMAC). Individual SES measures included educational attainment (<12 years, ≥12 years) and occupation type (managerial, non-managerial), while community SES was measured using Census block group poverty rate (<12%, 12-25%, ≥25%). SES measures were individually and simultaneously examined in linear regression models adjusting for age, gender, race, body mass index (BMI), occupational physical activity score (PAS), comorbidity count, and presence of hip symptoms.

RESULTS

In analyses among all individuals with rOA, models which included individual SES measures were observed to show that occupation was significantly associated with WOMAC Function (β =2.91, 95% Confidence Interval (CI) = 0.68-5.14), WOMAC Pain (β =0.93, 95% CI = 0.26-1.59) and WOMAC Total scores (β =4.05, 95% CI = 1.04-7.05), and education was significantly associated with WOMAC Function (β =3.57, 95% CI = 1.25-5.90) and WOMAC Total (β =4.56, 95% CI = 1.41-7.70) scores. In multivariable models including all SES measures simultaneously, most associations were attenuated. However, statistically significant results for education remained between WOMAC Function (β =2.83, 95% CI = 0.38-5.28) and WOMAC Total (β =3.48, 95% CI = 0.18-6.78), as well as for the association between occupation and WOMAC Pain (β =0.78, 95% CI = 0.08-1.48). In rOA subgroup analyses restricted to those with symptoms, we observed a significant increase in WOMAC Pain (β =1.36, 95% CI = 0.07-2.66) among individuals living in a block group with poverty rates greater than 25%, an association that remained when all SES measures were considered simultaneously (β =1.35, 95% CI = 0.06-2.64).

CONCLUSIONS

Lower individual and community SES are both associated with worse function and pain among adults with knee rOA.

The epidemiology and impact of pain in osteoarthritis

Osteoarthritis (OA) is the most common form of arthritis and a leading cause of disability worldwide, largely due to pain, the primary symptom of the disease. The pain experience in knee OA in particular is well-recognized as typically transitioning from intermittent weight-bearing pain to a more persistent, chronic pain. Methods to validly assess pain in OA studies have been developed to address the complex nature of the pain experience. The etiology of pain in OA is recognized to be multifactorial, with both intra-articular and extra-articular risk factors. Nonetheless, greater insights are needed into pain mechanisms in OA to enable rational mechanism-based management of pain. Consequences of pain related to OA contribute to a substantial socioeconomic burden.

Genetic factors in OA pathogenesis

Osteoarthritis (OA) is known to have an important genetic component and human genetic studies can help unravel the molecular mechanisms responsible for joint damage and nociception involved in OA. Genetic studies in humans have identified molecules involved in signaling cascades that are important for the pathology of the joint components such as the bone morphogenetic protein growth differentiation factor 5 (GDF5). Genomewide association scans (GWAS) in Asians have uncovered a likely role for structural extracellular matrix components (DVWA), and for molecules involved in immune response (HLA class II DQB1 and BTNL2) but these genes are not associated in Caucasian patients. In Caucasians a ~300 kilobase region in chromosome 7q22 containing several genes has been found to be reproducibly associated with OA. A recent European GWAS taking advantage of imputation techniques has uncovered a variant in the MCF2L gene as significantly associated with large joint OA. MCF2L is involved in neurotrophin mediated regulation of cell motility in the peripheral nervous system, and thus potentially implicated in nociception in OA. As the number of OA cases with genomewide genotyping increases it is expected that many more reproducible variants implicated in OA will be reported. This article is part of a Special Issue entitled "Osteoarthritis".

A role for PACE4 in osteoarthritis pain: evidence from human genetic association and null mutant phenotype

OBJECTIVES

The aim of this study was to assess if genetic variation in the PACE4 (paired amino acid converting enzyme 4) gene Pcsk6 influences the risk for symptomatic knee osteoarthritis (OA).

METHODS

Ten PCSK6 single nucleotide polymorphisms were tested for association in a discovery cohort of radiographic knee OA (n=156 asymptomatic and 600 symptomatic cases). Meta-analysis of the minor allele at rs900414 was performed in three additional independent cohorts (total n=674 asymptomatic and 2068 symptomatic). Pcsk6 knockout mice and wild-type C57BL/6 mice were compared in a battery of algesiometric assays, including hypersensitivity in response to intraplantar substance P, pain behaviours in response to intrathecal substance P and pain behaviour in the abdominal constriction test.

RESULTS

In the discovery cohort of radiographic knee OA, an intronic single nucleotide polymorphism at rs900414 was significantly associated with symptomatic OA. Replication in three additional cohorts confirmed that the minor allele at rs900414 was consistently increased among asymptomatic compared to symptomatic radiographic knee OA cases in all four cohorts. A fixed-effects meta-analysis yielded an OR=1.35 (95% CI 1.17 to 1.56; p=4.3×10(-5) and no significant between-study heterogeneity). Studies in mice revealed that Pcsk6 knockout mice were significantly protected against pain in a battery of algesiometric assays.

CONCLUSIONS

These results suggest that a variant in PCSK6 is strongly associated with protection against pain in knee OA, offering some insight as to why, in the presence of the same structural damage, some individuals develop chronic pain and others are protected. Studies in Pcsk6 null mutant mice further implicate PACE4 in pain.

Prevalence of knee pain and its influence on quality of life and physical function in the Korean elderly population: a community based cross-sectional study

To investigate the prevalence of knee pain and its influence on physical function and quality of life (QOL), we examined 504 community residents of Chuncheon, aged ≥ 50 yr. Demographic information was obtained by questionnaire, and radiographic evaluations consisted of weight-bearing semi-flexed knee anteroposterior radiographs. Self-reported QOL and function were assessed using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Short Form 12 (SF-12). Performance-based lower extremity function was assessed using the tests consisting of standing balance, usual walk and chair stands. The prevalence of knee pain was 46.2% (32.2% in men and 58.0% in women) and increased with age in women. After adjustment of confounders including the presence of knee OA, the subjects with knee pain had significantly worse WOMAC function and SF-12 scores compared to subjects without knee pain. Among the subjects with knee pain, women had worse WOMAC and SF-12 scores than men. Subjects with knee pain had worse physical performance score compared to those without knee pain, especially among females. In conclusion, the prevalence of knee pain is high (32.2% in men and 58.0% in women) in this elderly community population in Korea. Independent of knee OA and other confounding factors, subjects with knee pain have more than 5-fold increase in the risk of belonging to the worst lower extremity function compared to subjects without knee pain.

The contribution of osteoarthritis to functional limitations and disability

This article uses the Disablement Model conceptual framework to guide an analysis of the importance of osteoarthritis (OA) in the development of disability. The Disablement Model describes the development and progression of disablement from impairments to specific functional limitations and disability, and the hypothesized role of predisposing risk factors, extra-individual factors, and intra-individual factors. A wide range of population and clinical studies have characterized the unequivocal contribution of arthritis to the development of functional limitations and disability. Evidence overwhelmingly supports a significant, moderate independent contribution of arthritis to the onset and progression of functional limitations and disability. With respect to important risk factors for the development of functional limitations and disability among those with OA, the evidence provides strong support for the role of physical impairments along with other predisposing and intra-individual factors such as age, body mass index, obesity, lack of exercise, comorbid conditions, depression, and depressive symptoms. Extra-individual factors included need for aids and assistance, and lack of access to public or private transportation. Future disablement research must clarify the causal mechanisms behind a potential risk factor's impact on disability and delineate the interplay between and among the various hypothesized steps in the disablement process.

Clinically important improvement in function is common in people with or at high risk of knee OA: the MOST study

OBJECTIVE

To calculate the frequency of clinically important improvement in function over 30 months and identify risk factors in people who have or are at risk of knee osteoarthritis (OA).

METHODS

Subjects were from the Multicenter Osteoarthritis (MOST), a longitudinal study of persons with or at high risk of knee OA. We defined minimal clinically important improvement (MCII) with the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) physical function using 3 different methods. Baseline risk factors tested for improvement included age, sex, educational attainment, presence of radiographic knee OA (ROA), the number of comorbidities, body mass index (BMI), knee pain, walking speed, isokinetic knee extensor strength, depressive symptoms, physical activity, and medication usage. We used logistic regression to evaluate the association of baseline risk factors with MCII.

RESULTS

Of the 1801 subjects (mean age 63 yrs, BMI = 31, 63% women), most had mild limitations in baseline function (WOMAC = 19 +/- 11). Regardless of how defined, a substantial percentage of subjects (24%-39%) reached MCII at 30 months. Compared to their counterparts, people with MCII were less likely to have ROA and to use medications, and were more likely to have a lower BMI, less knee pain, a faster walking speed, more knee strength, and fewer depressive symptoms. After adjustment, MCII was 40% to 50% less likely in those with ROA, and 1.9 to 2.0 times more likely in those walking 1.0 meters/second faster than counterparts.

CONCLUSION

Clinically important improvement is frequent in people with or at high risk of knee OA. The absence of ROA and a faster walking speed appear to be associated with clinically important improvements.

The Staffordshire arthritis, musculoskeletal, and back assessment (SAMBA) study: a prospective observational study of patient outcome following referral to a primary-secondary care musculoskeletal interface service

BACKGROUND

Recent healthcare policy has shifted the management of musculoskeletal conditions in the UK away from secondary care towards Clinical Assessment and Treatment Services at the primary-secondary care interface. However, little is known about the outcome of patients with musculoskeletal conditions referred from primary care to Clinical Assessment and Treatment Services or how best to identify those patients at high risk of poor outcome in this setting. We describe the protocol for a twelve-month prospective observational study which aims to describe the outcome of patients referred to musculoskeletal and back pain services at the primary-secondary care interface and to develop simple prognostic measures to guide clinical prioritisation and triage.

METHODS/DESIGN

All patients referred over a twelve-month period from primary care to musculoskeletal and back pain clinics in the primary-secondary care interface Clinical Assessment and Treatment Service in North Staffordshire will be mailed a postal questionnaire prior to their consultation. This will collect information on quality of life, general health, anxiety and depression, pain, healthcare utilisation including medication use, occupational characteristics, and socio-demographics. At the consultation in the interface clinic, the clinical diagnosis, investigations requested, and clinical interventions will be recorded. Follow-up data for the twelve-month period subsequent to recruitment will be collected via mailed follow-up questionnaires at 6 and 12 months, and review of medical records.

DISCUSSION

This twelve-month prospective observational study of patients referred to a musculoskeletal Clinical Assessment and Treatment Service will assess the management and outcome of musculoskeletal care at the primary-secondary care interface as proposed in the Musculoskeletal Services Framework.