Predictors for response to rehabilitation in patients with hip or knee osteoarthritis: a comparison of logistic regression models with three different definitions of responder

Patient acceptance of care of a novel care pathway for those at risk of poor outcomes from musculoskeletal pain: A mixed methods study

OBJECTIVE

Investigate people's acceptance of specialist musculoskeletal care within a new care pathway for common musculoskeletal conditions (low back pain, neck pain/whiplash, knee osteoarthritis).

DESIGN

Convergent parallel mixed methods design referencing the Theoretical Framework of Acceptability. The study included a subset of participants (n = 29) at-risk of poor outcomes from the intervention arm of the PAthway of CarE for common musculoskeletal conditions (PACE-MSK) trial. In the PACE-MSK arm, participants received specialist physiotherapist care as an adjunct to the care provided by their primary healthcare professional(s). One-to-one semi-structured interviews were conducted around 3-months after commencing in the trial. Quantitative data were collected at baseline and 3-month follow-up (health-related quality of life, pain self-efficacy, global perceived change, satisfaction).

RESULTS

Five themes were identified (Expectations and beliefs shaped patient experience; Clinical expertise and competence influence acceptance; Person-centred care; Mechanisms facilitating beneficial responses to care; Gaps in care pathway implementation). There were positive individual changes in physical quality of life for 17/29 (59%) participants, mental health quality of life for 12/29 (41%), pain self-efficacy for 8/29 (28%) and global perceived change for 19/29 (66%). Management met expectations with the majority reporting high levels of satisfaction. Integrating the qualitative and quantitative data with the Theoretical Framework of Acceptability, there were complementary meta-inferences in the constructs of 'ethicality', 'intervention coherence', 'self-efficacy' and 'affective attitude'. Divergence was identified in 'perceived effectiveness'.

DISCUSSION

In general, there was positive acceptance of the care pathway by participants. Specialist physiotherapists' care was perceived as a positive addition to usual care.

Randomized Placebo-Controlled Trial of 60-Day Percutaneous Peripheral Nerve Stimulation Treatment Indicates Relief of Persistent Postoperative Pain, and Improved Function After Knee Replacement

OBJECTIVES

Total knee arthroplasty (TKA) is an effective surgery for end-stage knee osteoarthritis, but chronic postoperative pain and reduced function affect up to 20% of patients who undergo such surgery. There are limited treatment options, but percutaneous peripheral nerve stimulation (PNS) is a promising nonopioid treatment option for chronic, persistent postoperative pain. The objective of the present study was to evaluate the effect of a 60-day percutaneous PNS treatment in a multicenter, randomized, double-blind, placebo-controlled trial for treating persistent postoperative pain after TKA.

MATERIALS AND METHODS

Patients with postoperative pain after knee replacement were screened for this postmarket, institutional review board-approved, prospectively registered (NCT04341948) trial. Subjects were randomized to receive either active PNS or placebo (sham) stimulation. Subjects and a designated evaluator were blinded to group assignments. Subjects in both groups underwent ultrasound-guided placement of percutaneous fine-wire coiled leads targeting the femoral and sciatic nerves on the leg with postoperative pain. Leads were indwelling for eight weeks, and the primary efficacy outcome compared the proportion of subjects in each group reporting ≥50% reduction in average pain relative to baseline during weeks five to eight. Functional outcomes (6-minute walk test; 6MWT and Western Ontario and McMaster Universities Osteoarthritis Index) and quality of life (Patient Global Impression of Change) also were evaluated at end of treatment (EOT).

RESULTS

A greater proportion of subjects in the PNS groups (60%; 12/20) than in the placebo (sham) group (24%; 5/21) responded with ≥50% pain relief relative to baseline (p = 0.028) during the primary endpoint (weeks 5-8). Subjects in the PNS group also walked a significantly greater distance at EOT than did those in the placebo (sham) group (6MWT; +47% vs -9% change from baseline; p = 0.048, n = 18 vs n = 20 completed the test, respectively). Prospective follow-up to 12 months is ongoing.

CONCLUSIONS

This study provides evidence that percutaneous PNS decreases persistent pain, which leads to improved functional outcomes after TKA at EOT.

Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register

AIM

To examine the associations between individual- and disease-related factors and the odds of reaching a clinically relevant pain reduction in people with knee and/or hip osteoarthritis (OA) who underwent a first-line self-management program.

MATERIALS AND METHODS

An observational registry-based study including people with knee (n = 18,871) and hip (n = 7,767) OA who participated in a self-management program including education and exercise and had data recorded in the Better Management of patients with Osteoarthritis (BOA) register. We used multivariable logistic regression models to study the association between sex, age, body mass index (BMI), education, comorbidity, pain frequency, walking difficulties, willingness to undergo surgery and the odds of reaching a clinically relevant pain reduction (decrease of >33% on a 0-10 NRS scale) 3 and 12 months after the intervention. All analyses were stratified by joint (knee/hip).

RESULTS

Both in the short- and long-term follow-up, a younger age (18-65 years), a lower BMI (< 25), a higher level of education (university), the absence of comorbidities impacting the ability to walk, less frequent pain and not being willing to undergo surgery were associated with higher odds of reaching a clinically relevant pain reduction in people with knee OA. We found similar results for people with hip OA, but with larger uncertainty in the estimates (wider 95% CI).

CONCLUSION

Our study suggests that early fist line self-management interventions delivered when people have unilateral hip or knee OA with less frequent pain and are unwilling to undergo surgery, may be important for reaching a clinically relevant pain reduction after participation. Providing the most appropriate treatment to the right patient at the right time is a step in reducing the burden of OA for society and the patient.

Prognostic Factors for Health Outcomes After Exercise Therapy and Education in Individuals With Knee and Hip Osteoarthritis With or Without Comorbidities: A Study of 37,576 Patients Treated in Primary Care

OBJECTIVE

To identify prognostic factors for health outcomes following an 8-week supervised exercise therapy and education program for individuals with knee and hip osteoarthritis (OA) alone or with concomitant hypertension, heart or respiratory disease, diabetes mellitus, or depression.

METHODS

We included individuals with knee and/or hip OA from the Good Life With OsteoArthritis in Denmark (GLA:D) program. GLA:D consists of 2 patient education sessions and 12 supervised exercise therapy sessions. Before GLA:D, participants self-reported any comorbidities and were categorized into 8 comorbidity groups. Twenty-one potential prognostic factors (demographic information, clinical data, and performance-based physical function) gathered from participants and clinicians before the program were included. Outcomes were physical function using the 40-meter Fast-Paced Walk Test (FPWT), health-related quality of life using the 5-level EuroQol 5-domain (EQ-5D-5L) index score, and pain intensity using a visual analog scale (VAS; range 0-100) assessed before and immediately after the GLA:D program. Within each comorbidity group, associations of prognostic factors with outcomes were estimated using multivariable linear regression.

RESULTS

Data from 35,496 (40-meter FPWT) and 37,576 (EQ-5D-5L and VAS) participants were included in the analyses. Clinically relevant associations were demonstrated between age, self-efficacy, self-rated health, and pain intensity and change in 40-meter FPWT, EQ-5D-5L, or VAS scores across comorbidity groups. Furthermore, anxiety, education, physical function, and smoking were associated with outcomes among subgroups having depression or diabetes mellitus in addition to OA.

CONCLUSION

Age, self-efficacy, self-rated health, and pain intensity may be prognostic of change in health outcomes following an 8-week exercise therapy and patient education program for individuals with OA, irrespective of comorbidities.

Prognostic factors for the improvement of pain and disability following multidisciplinary rehabilitation in patients with chronic neck pain

Background

Recent clinical studies have demonstrated the effectiveness of specific, multidisciplinary, bio-psychosocial, rehabilitation programmes for chronic neck pain. However, prognostic factors for the improvement of pain and disability are mostly unknown. Therefore, the aim of this study was to explore prognostic factors associated with improvements in chronic neck pain following participation in a three-week, multidisciplinary, bio-psychosocial, rehabilitation programme.

Methods

In this observational, prospective cohort study, a total of 112 patients were assessed at the beginning, end, and 6 months following the completion of a multidisciplinary, bio-psychosocial, rehabilitation programme. Inclusion for participation in the rehabilitation programme depended upon an interdisciplinary pain assessment. The primary outcome was neck pain and disability, which was measured using the Northern American Spine Society questionnaire for pain+disability and was quantified with effect sizes (ES). Multivariable linear regression analyses were used to explore potential prognostic factors associated with improvements in pain and disability scores at discharge and at the 6-month follow-up period.

Results

The mean age of the patients was 59.7 years (standard deviation = 10.8), and 70.5% were female. Patients showed improvement in pain+disability at discharge (ES = 0.56; p < 0.001), which was sustained at the 6-month follow-up (ES = 0.56; p < 0.001). Prognostic factors associated with improvement in pain+disability scores at discharge included poor pain+disability baseline scores (partial, adjusted correlation r = 0.414, p < 0.001), older age (r = 0.223, p = 0.024), a good baseline cervical active range-of-motion (ROM) (r = 0.210, p < 0.033), and improvements in the Short-form 36 mental health scale (r = 0.197; p = 0.047) and cervical ROMs (r = 0.195, p = 0.048) from baseline values. Prognostic factors associated with improvements in pain+disability at the 6-month follow-up were similar and included poor pain+disability baseline scores (partial, adjusted correlation r = 0.364, p < 0.001), improvements in the Short-form 36 mental health scale (r = 0.232; p = 0.002), cervical ROMs (r = 0.247, p = 0.011), and better cervical ROM baseline scores. However, older age was not a factor (r = 0.134, p = 0.172).

Conclusions

Future prognostic models for treatment outcomes in chronic neck pain patients should consider cervical ROM and mental health status. Knowledge of prognostic factors may help in the adoption of individualized treatment for patients who are less likely to respond to multidisciplinary rehabilitation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04194-9.

Factors associated with poor self-reported function and quality of life in patients with end-stage knee or hip osteoarthritis immediately prior to total joint arthroplasty

INTRODUCTION

The aim was to evaluate patients' perception of function and physical and mental dimensions of health-related quality of life (HRQoL) in patients with end-stage knee or hip osteoarthritis (OA) immediately prior to surgery and to identify the factors associated with the outcomes.

MATERIAL AND METHODS

The study included 200 patients with end-stage OA (100 knee OA and 100 hip OA patients). Self-reported physical function was assessed using the Oxford Knee Score or Oxford Hip Score. Physical and mental dimensions of HRQoL were assessed using the physical and mental component summary scores of the 36-Item Short-Form Health Survey. Multivariate linear regression analysis was used to identify the sociodemographic, clinical and psychological factors associated with self-reported function and physical and mental dimensions of HRQoL.

RESULTS

End-stage knee or hip OA patients had poor function and physical dimension of HRQoL, while the mental dimension of HRQoL was not impaired. In knee OA, pain, flexion range of motion (ROM), catastrophizing, and anxiety were significantly associated with self-reported function (explained 56% of the variance), whereas catastrophizing explained 10% of the variance of the physical dimension of HRQoL. In hip OA, flexion ROM, catastrophizing and being employed were significantly associated with self-reported function (explained 44% of the variance), whereas catastrophizing and flexion ROM explained 34% of the variance of the physical dimension of HRQoL.

CONCLUSIONS

Many investigated factors were associated with poor self-reported function and HRQoL in knee and hip OA. However, the most important factors for both knee and hip OA were catastrophizing and flexion ROM.

Factors associated with health-related quality of life in Japanese patients with hip osteoarthritis: A cross-sectional study

Background/Purpose:

Chronic symptoms related with hip osteoarthritis (OA) can negatively affect health-related quality of life (HRQoL). The purpose of this study was to examine factors related to a HRQoL measure that considers an Asian lifestyle in Japanese patients with hip OA.

Methods:

Forty-seven female subjects participated. The dependent variable was the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ), which assessed HRQoL. Potential factors were measured as independent variables. After screening, potential variables were entered into a multiple regression analysis to determine which variables were related to HRQoL.

Results:

In the regression model, knee extension muscle strength on the unaffected side and hip flexion range of motion (ROM) on the affected side were associated with HRQoL. Higher strength and higher ROM were related to greater HRQoL.

Conclusion:

Results can help health-care providers develop appropriate rehabilitation programs for improving HRQoL in patients with hip OA.

Responder Profile to Pharmaceutical-Grade Chondroitin Sulfate: An Analysis of the CONCEPT Trial

Introduction

The recent CONCEPT study showed that 800 mg/day of pharmaceutical-grade chondroitin sulfate (CS) was superior to placebo and similar to celecoxib in reducing pain and improving function over 6 months in patients with symptomatic knee osteoarthritis (OA). We investigate, in the present study, whether a responder profile to CS could be defined (i.e., to determine a patient’s profile with the best response to treatment).

Methods

Subjects from the CS group of the CONCEPT study were included in the present analysis. Within the CS group, various subgroups were created on the basis of different categories of age, sex, body mass index, Kellgren and Lawrence grade, age since the beginning of OA, and baseline level of pain (i.e., VAS) or function (i.e., Lequesne index). The nonparametric Kruskal–Wallis (KW) test was applied to compare the VAS pain/Lequesne index evolutions between the subgroups, and the Dwass, Steel, Critchlow, Fligner (DSCF) procedure was used to compute multiple comparisons. The impact of various covariates on the VAS pain/Lequesne index evolution was assessed by means of multiple regression.

Results

Across all analyses, the probability of response to CS treatment was significantly associated with the duration between the date of diagnosis and the initiation of treatment. In other words, the shorter the interval between the diagnosis and the beginning of the treatment, the higher the response for both pain and function, particularly for patients with a duration of less than 5 years compared to patients with a duration of 10 years or more. No other criteria were found to be consistently associated with the response to CS treatment.

Conclusion

The treatment of OA with CS has the highest chance of success if administered in the early stage of the disease. Further research with other clinical outcomes should be carried out prior to widespread application of these findings.

Trial Registration

ClinicalTrials.gov identifier, NCT03200288.

Sociodemographic Inequalities in Outcomes of a Swedish Nationwide Self-Management Program for Osteoarthritis: Results from 22,741 Patients between Years 2008-2017

The aim of this study is to investigate if there are educational level and birthplace related differences in joint-related pain, health-related quality of life (HRQoL), willingness to undergo joint surgery, walking difficulties, physical activity level, fear-avoidance behavior before, as well as three and 12 months after participation in a structured self-management program for hip and knee osteoarthritis. Differences in adherence to and use of knowledge from the program were also investigated. An observational national register-based study was performed with a prospective longitudinal design using patient and physiotherapist-reported data on 22,741 complete cases from the National Quality Register for better management of patients with osteoarthritis (BOA) during years 2008–2017. At baseline and after three and 12 months follow-up, higher educational level and being domestic-born was associated with less joint-related pain, better HRQoL, lower willingness to undergo joint surgery, fewer walking difficulties, higher physical activity level, and less fear-avoidance behavior. Foreign born individuals demonstrated higher adherence to exercise and reported better use of the self-management program. The BOA self-management program may require further pedagogical refinement to suit participants of different sociodemographic backgrounds and health literacy. A more patient-centered delivery, sensitive to educational, ethnic, and cultural differences may potentially reduce inequalities in future outcomes.

Improving Patient Outcomes Following Total Knee Arthroplasty: Identifying Rehabilitation Pathways Based on Modifiable Psychological Risk and Resilience Factors

Total knee arthroplasty (TKA) is a commonly implemented elective surgical treatment for end-stage osteoarthritis of the knee, demonstrating high success rates when assessed by objective medical outcomes. However, a considerable proportion of TKA patients report significant dissatisfaction postoperatively, related to enduring pain, functional limitations, and diminished quality of life. In this conceptual analysis, we highlight the importance of assessing patient-centered outcomes routinely in clinical practice, as these measures provide important information regarding whether surgery and postoperative rehabilitation interventions have effectively remediated patients' real-world "quality of life" experiences. We propose a novel precision medicine approach to improving patient-centered TKA outcomes through the development of a multivariate machine-learning model. The primary aim of this model is to predict individual postoperative recovery trajectories. Uniquely, this model will be developed using an interdisciplinary methodology involving non-linear analysis of the unique contributions of a range of preoperative risk and resilience factors to patient-centered TKA outcomes. Of particular importance to the model's predictive power is the inclusion of a comprehensive assessment of modifiable psychological risk and resilience factors that have demonstrated relationships with TKA and other conditions in some studies. Despite the potential for patient psychological factors to limit recovery, they are typically not routinely assessed preoperatively in this patient group, and thus can be overlooked in rehabilitative referral and intervention decision-making. This represents a research-to-practice gap that may contribute to adverse patient-centered outcomes. Incorporating psychological risk and resilience factors into a multivariate prediction model could improve the detection of patients at risk of sub-optimal outcomes following TKA. This could provide surgeons and rehabilitation providers with a simplified tool to inform postoperative referral and intervention decision-making related to a range of interdisciplinary domains outside their usual purview. The proposed approach could facilitate the development and provision of more targeted rehabilitative interventions on the basis of identified individual needs. The roles of several modifiable psychological risk and resilience factors in recovery are summarized, and intervention options are briefly presented. While focusing on rehabilitation following TKA, we advocate for the broader utilization of multivariate prediction models to inform individually tailored interventions targeting a range of health conditions.

Outcomes and Factors Influencing Response to an Individualized Multidisciplinary Chronic Disease Management Program for Hip and Knee Osteoarthritis

BACKGROUND

The objective of the study was to investigate the effectiveness of, and factors associated with, response to a chronic disease management program for patients with hip and knee osteoarthritis (OA).

METHODS

Over a 2-year period (2012-2014), 218 patients (97 hip OA; 121 knee OA) were managed with an individualized program of interventions that could include education, physiotherapy, orthotics, occupational therapy, or dietitian referral. Changes in Oxford Hip Score or Oxford Knee Score and Short Form-12 (SF-12) Physical and Mental Component Summary Score (PCS, MCS) were analyzed by joint affected, both unadjusted, and gender and age adjusted. A further analysis also adjusted for body mass index.

RESULTS

At mean 12-month follow-up, patients with knee OA had a statistically significant improvement in Oxford Knee Score and PCS, while patients with hip OA had a statistically significant deterioration in all 3 scores. There was evidence that these changes differed between joints for Oxford and PCS scores. Older age was associated with worse outcomes for Oxford scores. Higher body mass index was associated with worse outcomes for Oxford and PCS scores. Patients with hip OA (35%) were more likely to deteriorate to a clinically significant extent (5 points) for Oxford scores than those with knee OA. Gender was not associated with outcomes. Patients with hip OA (54%) were more likely than those with knee OA (24%) to have subsequently had surgery (P < .001).

CONCLUSIONS

Patients with knee OA were more likely to improve with a chronic disease management plan than patients with hip OA and efforts should be directed to them.

A Feasibility Study of Percutaneous Peripheral Nerve Stimulation for the Treatment of Postoperative Pain Following Total Knee Arthroplasty

INTRODUCTION

The objective of the present feasibility study was to investigate the use of a new treatment modality-percutaneous peripheral nerve stimulation (PNS)-in controlling the often severe and long-lasting pain following total knee arthroplasty (TKA).

METHODS

For patients undergoing a primary, unilateral TKA, both femoral and sciatic open-coil percutaneous leads (SPR Therapeutics, Cleveland, OH) were placed up to seven days prior to surgery using ultrasound guidance. The leads were connected to external stimulators and used both at home and in the hospital for up to six weeks total.

RESULTS

In six of seven subjects (86%), the average of daily pain scores across the first two weeks was <4 on the 0-10 Numeric Rating Scale for pain. A majority of subjects (four out of seven; 57%) had ceased opioid use within the first week (median time to opioid cessation for all subjects was six days). Gross sensory/motor function was maintained during stimulation, enabling stimulation during physical therapy and activities of daily living. At 12 weeks following surgery, six of seven subjects had improved by >10% on the Six-Minute Walk Test compared to preoperative levels, and WOMAC scores improved by an average of 85% compared to before surgery. No falls, motor block, or lead infections were reported.

CONCLUSIONS

This feasibility study suggests that for TKA, ultrasound-guided percutaneous PNS is feasible in the immediate perioperative period and may provide analgesia without the undesirable systemic effects of opioids or quadriceps weakness induced by local anesthetics-based peripheral nerve blocks.

Pain and functional trajectories in symptomatic knee osteoarthritis over up to 12 weeks of exercise exposure

OBJECTIVE

Exercise is the recommended treatment for knee osteoarthritis (OA). However, heterogeneous patterns in treatment response are poorly understood. Our purpose was to identify pain and functional trajectories from exercise interventions in knee OA, and to determine their association with baseline factors.

METHODS

Prospective cohort of 171 participants (mean age 61 years; BMI 32 kg/m², 71% female; 57% white) with symptomatic knee OA from a randomized trial comparing 12-week Tai Chi and Physical Therapy. We analyzed weekly Western Ontario and McMaster Osteoarthritis Index (WOMAC) pain (0-500) and function (0-1700) scores using group-based trajectory models. Associations between baseline factors and trajectories were examined using multinomial logistic regression.

RESULTS

We identified four pain trajectories: Lower-Early Improvement (43%), Moderate-Early Improvement (32%), Higher-Delayed Improvement (15%), and Higher-No Improvement (10%). We found similar trajectories for function, except that the lower function trajectories diverged into gradual (12%) or delayed-improvement (15%). Compared with the Lower-Early Improvement pain trajectory, moderate and higher trajectories were associated with poorer physical and psychosocial health. A similar pattern of associations were found among the function trajectories.

CONCLUSIONS

We found four distinct trajectories for pain and function over up to 12-weeks of exercise interventions. While most participants experienced improvements over a short-term exposure, subgroups with greater baseline pain/physical disability had either gradual, delayed, or no improvements. These findings help disentangle the heterogeneity of treatment response and may advance patient-centered care in knee OA.

Wearable sensors to predict improvement following an exercise intervention in patients with knee osteoarthritis

Background

Muscle strengthening exercises consistently demonstrate improvements in the pain and function of adults with knee osteoarthritis, but individual response rates can vary greatly. Identifying individuals who are more likely to respond is important in developing more efficient rehabilitation programs for knee osteoarthritis. Therefore, the purpose of this study was to determine if pre-intervention multi-sensor accelerometer data (e.g., back, thigh, shank, foot accelerometers) and patient reported outcome measures (e.g., pain, symptoms, function, quality of life) can retrospectively predict post-intervention response to a 6-week hip strengthening exercise intervention in a knee OA cohort.

Methods

Thirty-nine adults with knee osteoarthritis completed a 6-week hip strengthening exercise intervention and were sub-grouped as Non-Responders, Low-Responders, or High-Responders following the intervention based on their change in patient reported outcome measures. Pre-intervention multi-sensor accelerometer data recorded at the back, thigh, shank, and foot and Knee Injury and Osteoarthritis Outcome Score subscale data were used as potential predictors of response in a discriminant analysis of principal components.

Results

The thigh was the single best placement for classifying responder sub-groups (74.4%). Overall, the best combination of sensors was the back, thigh, and shank (81.7%), but a simplified two sensor solution using the back and thigh was not significantly different (80.0%; p = 0.27).

Conclusions

While three sensors were best able to identify responders, a simplified two sensor array at the back and thigh may be the most ideal configuration to provide clinicians with an efficient and relatively unobtrusive way to use to optimize treatment.

Electronic supplementary material

The online version of this article (10.1186/s12984-017-0309-z) contains supplementary material, which is available to authorized users.

Mindfulness Is Associated With Treatment Response From Nonpharmacologic Exercise Interventions in Knee Osteoarthritis

OBJECTIVE

To examine the association between baseline mindfulness and response from exercise interventions in knee osteoarthritis (OA).

DESIGN

Cohort study; responder analysis of a clinical trial subset.

SETTING

Urban tertiary care academic hospital.

PARTICIPANTS

Participants with symptomatic, radiographic knee OA (N=86; mean age, 60y; 74% female; 48% white).

INTERVENTIONS

Twelve weeks (twice per week) of Tai Chi or physical therapy exercise.

MAIN OUTCOME MEASURES

Treatment response was defined using Osteoarthritis Research Society International criteria indicating meaningful improvements in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, WOMAC function, or Patient Global Assessment scores. At baseline, participants completed the Five Facet Mindfulness Questionnaire (mean total score, 142±17) and were grouped into 3 categories of total mindfulness: higher, medium, or lower. Relative risk (RR) ratios were used to compare treatment response across groups.

RESULTS

Participants with higher total mindfulness were 38% (95% confidence interval [CI], 1.05-1.83) more likely to meet responder criteria than those with lower mindfulness. We found no significant difference between medium and lower mindfulness groups (RR=1.0; 95% CI, 0.69-1.44). Among the 5 mindfulness facets, medium acting-with-awareness was 46% (95% CI, 1.09-1.96) more likely to respond than lower acting-with-awareness, and higher acting-with-awareness was 34% more likely to respond, but this did not reach significance (95% CI, 0.97-1.86).

CONCLUSIONS

In this study, higher mindfulness, primarily driven by its acting-with-awareness facet, was significantly associated with a greater likelihood of response to nonpharmacologic exercise interventions in knee OA. This suggests that mindfulness-cultivating interventions may increase the likelihood of response from exercise.

Patient, Provider, and Combined Interventions for Managing Osteoarthritis in Primary Care: A Cluster Randomized Trial

BACKGROUND

A single-site study showed that a combined patient and provider intervention improved outcomes for patients with knee osteoarthritis, but it did not assess separate effects of the interventions.

OBJECTIVE

To examine whether patient-based, provider-based, and patient-provider interventions improve osteoarthritis outcomes.

DESIGN

Cluster randomized trial with assignment to patient, provider, and patient-provider interventions or usual care. (ClinicalTrials.gov: NCT01435109).

SETTING

10 Duke University Health System community-based primary care clinics.

PARTICIPANTS

537 outpatients with symptomatic hip or knee osteoarthritis.

INTERVENTION

The telephone-based patient intervention focused on weight management, physical activity, and cognitive behavioral pain management. The provider intervention involved electronic delivery of patient-specific osteoarthritis treatment recommendations to providers.

MEASUREMENTS

The primary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score at 12 months. Secondary outcomes were objective physical function (Short Physical Performance Battery) and depressive symptoms (Patient Health Questionnaire). Linear mixed models assessed the difference in improvement among groups.

RESULTS

No difference was observed in WOMAC score changes from baseline to 12 months in the patient (-1.5 [95% CI, -5.1 to 2.0]; P = 0.40), provider (2.5 [CI, -0.9 to 5.9]; P = 0.152), or patient-provider (-0.7 [CI, -4.2 to 2.8]; P = 0.69) intervention groups compared with usual care. All groups had improvements in WOMAC scores at 12 months (range, -3.7 to -7.7). In addition, no differences were seen in objective physical function or depressive symptoms at 12 months in any of the intervention groups compared with usual care.

LIMITATIONS

The study involved 1 health care network. Data on provider referrals were not collected.

CONCLUSION

Contrary to a previous study of a combined patient and provider intervention for osteoarthritis in a Department of Veterans Affairs medical center, this study found no statistically significant improvements in the osteoarthritis intervention groups compared with usual care.

PRIMARY FUNDING SOURCE

National Institute of Arthritis and Musculoskeletal and Skin Diseases.

Can We Predict Those With Osteoarthritis Who Will Worsen Following a Chronic Disease Management Program?

OBJECTIVE

To identify predictors of worsening symptoms and overall health of the treated hip or knee joint following 26 weeks of a nonsurgical chronic disease management program for hip and knee osteoarthritis (OA) and to examine the consistency of these predictors across 3 definitions of worsening.

METHODS

This prospective cohort study followed 539 participants of the program for 26 weeks. The 3 definitions of worsening included symptomatic worsening based on change in the Western Ontario and McMaster Universities Osteoarthritis Index Global score (WOMAC-G) measuring pain, stiffness, and function; a transition scale that asked about overall health of the treated hip or knee joint; and a composite outcome including both. Multivariate logistic regression models were constructed for the 3 definitions of worsening.

RESULTS

Complete data were available for 386 participants: mean age was 66.3 years, 69% were female, 85% reported knee joint pain as primary symptom (signal joint), 46% were waitlisted for total joint arthroplasty (TJA). TJA waitlist status, signal joint, 6-Minute Walk Test (6MWT), depressive symptoms, pain, and age were independently associated with at least 1 definition of worsening. TJA waitlist status and 6MWT remained in the multivariate models for the transition and composite definitions of worsening.

CONCLUSION

Participants reporting worsening on the transition scale did not consistently meet the WOMAC-G definition of worsening symptoms. TJA waitlist status was predictive of the composite definition of worsening, a trend apparent for the transition definition. However, variables that predict worsening remain largely unknown. Further research is required to direct comprehensive and targeted management of patients with hip and knee OA.

Factors for Assessing the Effectiveness of Early Rehabilitation after Minimally Invasive Total Knee Arthroplasty: A Prospective Cohort Study

The effectiveness of current rehabilitation programs is supported by high-level evidence from the results of randomized controlled trials, but an increasing number of patients are not discharged from the hospital because of the schedule of the critical path (CP). The present study aimed to determine which factors can be used to assess the effectiveness of early rehabilitation. We enrolled 123 patients with medial knee osteoarthritis (OA) who had undergone unilateral minimally invasive total knee arthroplasty for the first time. The following factors were assessed preoperatively: the maximum isometric muscle strength of the knee extensors and flexors, maximum knee and hip joint angle, pain, 5-m maximum walking speed, sex, age, body mass index, exercise habits, Kellgren-Lawrence grade, femorotibial angle, failure side (bilateral or unilateral knee OA), and functional independence measure. We re-evaluated physical function (i.e., muscle strength, joint angle, and pain) and motor function (5-m maximum walking speed) 14 days postoperatively. Changes in physical function, motor function (5-m maximum walking speed), and number of days to independent walking were used as explanatory variables. The postoperative duration of hospitalization (in days) was used as the dependent variable in multivariate analyses. These analyses were adjusted for sex, age, body mass index, exercise habits, Kellgren-Lawrence grade, femorotibial angle, failure side, and functional independence measure. The duration of hospitalization was significantly affected by the number of days to independent walking (p < 0.001, β = 0.507) and a change in the 5-m maximum walking speed (p = 0.016, β = -0.262). Multiple regression analysis showed that the radiographic knee grade (p = 0.029, β = 0.239) was a significant confounding factor. Independent walking and walking speed recovery were considered to reduce the duration of hospitalization. Therefore, these indices can be used to assess the effectiveness of early rehabilitation.

A Combined Patient and Provider Intervention for Management of Osteoarthritis in Veterans: A Randomized Clinical Trial

BACKGROUND

Management of osteoarthritis requires both medical and behavioral strategies, but some recommended therapies are underused.

OBJECTIVE

To examine the effectiveness of a combined patient and provider intervention for improving osteoarthritis outcomes.

DESIGN

Cluster randomized clinical trial with assignment to osteoarthritis intervention and usual care groups. (ClinicalTrials.gov: NCT01130740).

SETTING

Department of Veterans Affairs Medical Center in Durham, North Carolina.

PARTICIPANTS

30 providers (clusters) and 300 outpatients with symptomatic hip or knee osteoarthritis.

INTERVENTION

The telephone-based patient intervention focused on weight management, physical activity, and cognitive behavioral pain management. The provider intervention involved delivery of patient-specific osteoarthritis treatment recommendations to primary care providers through the electronic medical record.

MEASUREMENTS

The primary outcome was total score on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at 12 months. Secondary outcomes were WOMAC function and pain subscale scores, physical performance (Short Physical Performance Battery), and depressive symptoms (Patient Health Questionnaire-8). Linear mixed models that were adjusted for clustering of providers assessed between-group differences in improvement in outcomes.

RESULTS

At 12 months, WOMAC scores were 4.1 points lower (indicating improvement) in the osteoarthritis intervention group versus usual care (95% CI, -7.2 to -1.1 points; P = 0.009). WOMAC function subscale scores were 3.3 points lower in the intervention group (CI, -5.7 to -1.0 points; P = 0.005). WOMAC pain subscale scores (P = 0.126), physical performance, and depressive symptoms did not differ between groups. Although more patients in the osteoarthritis intervention group received provider referral for recommended osteoarthritis treatments, the numbers who received them did not differ.

LIMITATION

The study was conducted in a single Veterans Affairs medical center.

CONCLUSION

The combined patient and provider intervention resulted in modest improvement in self-reported physical function in patients with hip and knee osteoarthritis.

PRIMARY FUNDING SOURCE

Department of Veterans Affairs, Health Services Research and Development Service.

Gait Biomechanics and Patient-Reported Function as Predictors of Response to a Hip Strengthening Exercise Intervention in Patients with Knee Osteoarthritis

Objective

Muscle strengthening exercises have been shown to improve pain and function in adults with mild-to-moderate knee osteoarthritis, but individual response rates can vary greatly. Predicting individuals who respond and those who do not is important in developing a more efficient and effective model of care for knee osteoarthritis (OA). Therefore, the purpose of this study was to use pre-intervention gait kinematics and patient-reported outcome measures to predict post-intervention response to a 6-week hip strengthening exercise intervention in patients with mild-to-moderate knee OA.

Methods

Thirty-nine patients with mild-to-moderate knee osteoarthritis completed a 6-week hip-strengthening program and were subgrouped as Non-Responders, Low-Responders, or High-Responders following the intervention based on their change in Knee injury Osteoarthritis Outcome Score (KOOS). Predictors of responder subgroups were retrospectively determined from baseline patient-reported outcome measures and kinematic gait parameters in a discriminant analysis of principal components. A 3–4 year follow-up on 16 of the patients with knee OA was also done to examine long-term changes in these parameters.

Results

A unique combination of patient-reported outcome measures and kinematic factors was able to successfully subgroup patients with knee osteoarthritis with a cross-validated classification accuracy of 85.4%. Lower patient-reported function in daily living (ADL) scores and hip frontal plane kinematics during the loading response were most important in classifying High-Responders from other sub-groups, while a combination of hip, knee, ankle kinematics were used to classify Non-Responders from Low-Responders.

Conclusion

Patient-reported outcome measures and objective biomechanical gait data can be an effective method of predicting individual treatment success to an exercise intervention. Measuring gait kinematics, along with patient-reported outcome measures in a clinical setting can be useful in helping make evidence-based decisions regarding optimal treatment for patients with knee OA.

Pain sensitisation and the risk of poor outcome following physiotherapy for patients with moderate to severe knee osteoarthritis: protocol for a prospective cohort study

INTRODUCTION

Pain is the dominant symptom of knee osteoarthritis (OA), and recent evidence suggests factors outside of local joint pathology, such as pain sensitisation, can contribute significantly to the pain experience. It is unknown how pain sensitisation influences outcomes from commonly employed interventions such as physiotherapy. The aims of this study are, first, to provide a comprehensive description of the somatosensory characteristics of people with pain associated with knee OA. Second, we will investigate if indicators of pain sensitisation in patients with knee osteoarthritis are predictive of non-response to physiotherapy.

METHODS AND ANALYSIS

This is a multicentre prospective cohort study with 140 participants. Eligible patients with moderate to severe symptomatic knee osteoarthritis will be identified at outpatient orthopaedic and rheumatology clinics. A baseline assessment will provide a comprehensive description of the somatosensory characteristics of each participant by means of clinical examination, quantitative sensory testing, and validated questionnaires measuring pain and functional capacity. Participants will then undergo physiotherapy treatment. The primary outcome will be non-response to physiotherapy on completion of the physiotherapy treatment programme as defined by the Osteoarthritis Research Society International treatment responder criteria. A principal component analysis will identify measures related to pain sensitisation to include in the predictive model. Regression analyses will explore the relationship between responder status and pain sensitisation while accounting for confounders.

ETHICS AND DISSEMINATION

This study has been approved by St James' Hospital/AMNCH Research Ethics Committee and by the St Vincent's Healthcare Group Ethics and Medical Research Committee. The results will be presented at international conferences and published in a peer review journal.

TRIAL REGISTRATION NUMBER

NCT02310945.

Does clinical presentation predict response to a nonsurgical chronic disease management program for endstage hip and knee osteoarthritis?

OBJECTIVE

To identify baseline characteristics of participants who will respond favorably following 6 months of participation in a chronic disease management program for hip and knee osteoarthritis (OA).

METHODS

This prospective cohort study assessed 559 participants at baseline and following 6 months of participation in the Osteoarthritis Chronic Care Program. Response was defined as the minimal clinically important difference of an 18% and 9-point absolute improvement in the Western Ontario and McMaster Universities Arthritis Index global score. Multivariate logistic regression modeling was used to identify predictors of response.

RESULTS

Complete data were available for 308 participants. Those who withdrew within the study period were imputed as nonresponders. Three variables were independently associated with response: signal joint (knee vs hip), sex, and high level of comorbidity. Index joint and sex were significant in the multivariate model, but the model was not a sensitive predictor of response.

CONCLUSION

Strong predictors of response to a chronic disease management program for hip and knee OA were not identified. The significant predictors that were found should be considered in future studies.

Predictors of short-term outcome to exercise and manual therapy for people with hip osteoarthritis

BACKGROUND

Physical therapy for hip osteoarthritis (OA) has shown short-term effects but limited long-term benefit. There has been limited research, with inconsistent results, in identifying prognostic factors associated with a positive response to physical therapy.

OBJECTIVES

The purpose of this study was to identify potential predictors of response to physical therapy (exercise therapy [ET] with or without adjunctive manual therapy [MT]) for hip OA based on baseline patient-specific and clinical characteristics.

DESIGN

A prognostic study was conducted.

METHODS

Secondary analysis of data from a multicenter randomized controlled trial (RCT) (N=131) that evaluated the effectiveness of ET and ET+MT for hip OA was undertaken. Treatment response was defined using OMERACT/OARSI responder criteria. Ten baseline measures were used as predictor variables. Regression analyses were undertaken to identify predictors of outcome. Discriminative ability (sensitivity, specificity, and likelihood ratios) of significant variables was calculated.

RESULTS

The RCT results showed no significant difference in most outcomes between ET and ET+MT at 9 and 18 weeks posttreatment. Forty-six patients were classified as responders at 9 weeks, and 36 patients were classified as responders at 18 weeks. Four baseline variables were predictive of a positive outcome at 9 weeks: male sex, pain with activity (<6/10), Western Ontario and McMaster Universities Osteoarthritis Index physical function subscale score (<34/68), and psychological health (Hospital Anxiety and Depression Scale score <9/42). No predictor variables were identified at the 18-week follow-up. Prognostic accuracy was fair for all 4 variables (sensitivity=0.5-0.58, specificity=0.57-0.72, likelihood ratios=1.25-1.77), indicating fair discriminative ability at predicting treatment response.

LIMITATIONS

The short-term follow-up limits the interpretation of results, and the low number of identified responders may have resulted in possible overfitting of the predictor model.

CONCLUSIONS

The authors were unable to identify baseline variables in patients with hip OA that indicate those most likely to respond to treatment due to low discriminative ability. Further validation studies are needed to definitively define the best predictors of response to physical therapy in people with hip OA.

How to define responders in osteoarthritis

BACKGROUND

Osteoarthritis is a clinical syndrome of failure of the joint accompanied by varying degrees of joint pain, functional limitation, and reduced quality of life due to deterioration of articular cartilage and involvement of other joint structures.

SCOPE

Regulatory agencies require relevant clinical benefit on symptoms and structure modification for registration of a new therapy as a disease-modifying osteoarthritis drug (DMOAD). An international Working Group of the European Society on Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO) and International Osteoporosis Foundation was convened to explore the current burden of osteoarthritis, review current regulatory guidelines for the conduct of clinical trials, and examine the concept of responder analyses for improving drug evaluation in osteoarthritis.

FINDINGS

The ESCEO considers that the major challenges in DMOAD development are the absence of a precise definition of the disease, particularly in the early stages, and the lack of consensus on how to detect structural changes and link them to clinically meaningful endpoints. Responder criteria should help identify progression of disease and be clinically meaningful. The ideal criterion should be sensitive to change over time and should predict disease progression and outcomes such as joint replacement.

CONCLUSION

The ESCEO considers that, for knee osteoarthritis, clinical trial data indicate that radiographic joint space narrowing >0.5 mm over 2 or 3 years might be a reliable surrogate measure for total joint replacement. On-going research using techniques such as magnetic resonance imaging and biochemical markers may allow the identification of these patients earlier in the disease process.

Association of the sense of coherence with physical and psychosocial health in the rehabilitation of osteoarthritis of the hip and knee: a prospective cohort study

Background

According to Antonovsky’s salutogenic concept, a strong sense of coherence is associated with physical and psychological health. The goal of this study was to analyze the association of Antonovsky’s sense of coherence with physical and psychosocial health components in patients with hip and knee osteoarthritis before and after in- and outpatient rehabilitation.

Methods

Prospective cohort study with 335 patients, 136 (41%) with hip and 199 (59%) with knee osteoarthritis. The outcome was measured by Short Form-36 (SF-36), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Sense of Coherence (SOC-13). Baseline scores of the SF-36 and WOMAC scales and the observed effect sizes after rehabilitation were correlated with the baseline SOC-13. These correlations of the SF-36 scales were compared to the Factor Score Coefficients for the Mental Component Summary of SF-36, which quantify the factor load on the psychosocial dimension. Predictive impact of the baseline SOC-13 for the SF-36 and WOMAC scales (baseline scores and effect sizes) was then determined by multivariate linear regression controlled for possible confounders.

Results

At baseline, the SOC-13 correlated with the WOMAC scores between r = 0.18 (stiffness) and r = 0.25 (pain) and with the SF-36 scores between r = 0.10 (physical functioning) and r = 0.53 (mental health). The correlation of these SF-36 correlation coefficients to the Factor Score Coefficient of the SF-36 Mental Component Summary was r = 0.95. The correlations for the effect sizes (baseline → discharge) with the baseline SOC-13 global score were all negative and varied between r = 0.00 (physical functioning) and r = −0.19 (social functioning). In the multivariate linear regression model, the explained variance of the SF-36 scores by the baseline SOC-13 increased continuously from physical to psychosocial health dimensions (from 12.9% to 29.8%). This gradient was consistently observed for both the baseline scores and the effect sizes. The results of the WOMAC were consistent with the physical health scales of SF-36.

Conclusions

The sense of coherence was associated with psychosocial health dimensions but hardly with physical health. The higher the load of a scale on the psychosocial dimension the higher was its correlation to the sense of coherence. This is in contrast to the idea of Antonovsky who predicted high associations with both mental and physical health.

Which prognostic factors for low back pain are generic predictors of outcome across a range of recovery domains?

BACKGROUND

Recovery from low back pain (LBP) is multidimensional and requires the use of multiple-response (outcome) measures to fully reflect these many dimensions. Predictive prognostic variables that are present or stable in all or most predictive models that use different outcome measures could be considered "universal" prognostic variables.

OBJECTIVE

The aim of this study was to explore the potential of universal prognostic variables in predictive models for 4 different outcome measures in patients with mechanical LBP.

DESIGN

Predictive modeling was performed using data extracted from a randomized controlled trial. Four prognostic models were created using backward stepwise deletion logistic, Poisson, and linear regression.

METHODS

Data were collected from 16 outpatient physical therapy facilities in 10 states. All 149 patients with LBP were treated with manual therapy and spine strengthening exercises until discharge. Four different measures of response were used: Oswestry Disability Index and Numeric Pain Rating Scale change scores, total visits, and report of rate of recovery.

RESULTS

The set of statistically significant predictors was dependent on the definition of response. All regression models were significant. Within both forms of the 4 models, meeting the clinical prediction rule for manipulation at baseline was present in all 4 models, whereas no irritability at baseline and diagnosis of sprains and strains were present in 2 of 4 of the predictive models.

LIMITATIONS

The primary limitation is that this study evaluated only 4 of the multiple outcome measures that are pertinent for patients with LBP.

CONCLUSIONS

Meeting the clinical prediction rule was prognostic for all outcome measures and should be considered a universal prognostic predictor. Other predictive variables were dependent on the outcomes measure used in the predictive model.

Targeting care: tailoring nonsurgical management according to clinical presentation

International evidence-based guidelines recommend a multitude of nonsurgical treatment options for the management of osteoarthritis. This article summarizes the evidence available for patient characteristics that have been analyzed as potential predictors of response to nonsurgical interventions for patients with hip and knee osteoarthritis. The specific variables targeted for this review include body mass index, psychological factors, muscle strength, tibiofemoral alignment, radiographic changes, and signs of inflammation. Several studies provide moderate to good evidence of potential predictors of response to nonsurgical treatments, and areas for future research are illuminated.

Clinically important improvement in the WOMAC and predictor factors for response to non-specific non-steroidal anti-inflammatory drugs in osteoarthritic patients: a prospective study

Background

The aims of the present study were first to detect MCID for WOMAC in a Moroccan population, and second, to identify the best pre-treatment predictors on the change of health after treatment by non-specific, non-steroidal anti-inflammatory drugs (NSAIDs), and to evaluate whether the predictors were dependent on the choice of the response criterion.

Methods

The study involved 173 patients with osteoarthritis in whom primary care physicians decided to start treatment with non-selective NSAIDs. Assessments at admission and after 6 weeks were conducted. In order to determine the threshold levels associated with a definition of clinically important improvement, the receiver operating characteristic method was used. Three different measures of response to a 6-week NSAIDs treatment were used: one indirect measure (MCID in the total WOMAC score), one direct measure (transition question) and a combination of both criteria.

Results

Eighty patients (46.3%) reported "a slightly better" general health status compared to that of 6 weeks before NSAIDs treatment. The MCID proportion is a 16.0% reduction in WOMAC. The most stable pre-treatment predictors on the improvement of health after treatment by NSAIDs were the absence of previous knee injury and a high level of education.

Conclusions

In our data, a 16.0% reduction of the total WOMAC score from baseline was associated with the highest degree of improvement on the transition scale category. This cut-off point had good accuracy, and should be appropriate for use in the interpretation of clinical studies results, as well as in clinical care.

The remodeling of collagen fibers in rats ankles submitted to immobilization and muscle stretch protocol

To evaluate the remodeling of collagen fibers in the articular cartilage of rat ankles, with and without immobilization, after application of muscle stretching protocol. Twenty three Wistar rats were divided into four groups: immobilized (I), n=6; immobilized and stretched (IS), n=6; stretched (S), n=6 and control (C), n=5. The animals in groups I and IS were submitted to immobilization. After the period of immobilization, the animals in groups IS and S were submitted to a muscle stretching protocol. At the end of the experiment, the animals were euthanized and the joints removed, processed and stained with Picrosirius red. The analysis was carried out using a polarized light microscope. The density of collagen fibers were quantified according to the intensity of birefringence displayed. By way of statistical analyses, the right and left hind limbs of the different groups were compared based on the total density of collagen fibers, the density of thick collagen fibers and the density of thin collagen fibers. Immobilization promoted a reduction in density of the thin fibers and of total collagen. The muscle stretching protocol after immobilization promoted a reduction in density of the total collagen and of the thick fibers, but the density of the thin fibers showed the same values as control. The collagen fibers were remodeled by the different stimuli. Immobilization was harmful to the collagen fibers and the muscle stretching protocol only recovered the thin collagen fibers.

Exercise and manual physiotherapy arthritis research trial (EMPART): a multicentre randomised controlled trial

Background

Osteoarthritis (OA) of the hip is a major cause of functional disability and reduced quality of life. Management options aim to reduce pain and improve or maintain physical functioning. Current evidence indicates that therapeutic exercise has a beneficial but short-term effect on pain and disability, with poor long-term benefit. The optimal content, duration and type of exercise are yet to be ascertained. There has been little scientific investigation into the effectiveness of manual therapy in hip OA. Only one randomized controlled trial (RCT) found greater improvements in patient-perceived improvement and physical function with manual therapy, compared to exercise therapy.

Methods and design

An assessor-blind multicentre RCT will be undertaken to compare the effect of a combination of manual therapy and exercise therapy, exercise therapy only, and a waiting-list control on physical function in hip OA. One hundred and fifty people with a diagnosis of hip OA will be recruited and randomly allocated to one of 3 groups: exercise therapy, exercise therapy with manual therapy and a waiting-list control. Subjects in the intervention groups will attend physiotherapy for 6–8 sessions over 8 weeks. Those in the control group will remain on the waiting list until after this time and will then be re-randomised to one of the two intervention groups. Outcome measures will include physical function (WOMAC), pain severity (numerical rating scale), patient perceived change (7-point Likert scale), quality of life (SF-36), mood (hospital anxiety and depression scale), patient satisfaction, physical activity (IPAQ) and physical measures of range of motion, 50-foot walk and repeated sit-to stand tests.

Discussion

This RCT will compare the effectiveness of the addition of manual therapy to exercise therapy to exercise therapy only and a waiting-list control in hip OA. A high quality methodology will be used in keeping with CONSORT guidelines. The results will contribute to the evidence base regarding the clinical efficacy for physiotherapy interventions in hip OA.

Trial Registration

Number: NCT00709566

Comorbidity, limitations in activities and pain in patients with osteoarthritis of the hip or knee

Background

This study aims to contribute to the knowledge of the influence of comorbidity in OA. The objectives of the study were (i) to describe the prevalence of comorbidity and (ii) to describe the relationship between comorbidity (morbidity count, severity and the presence of specific diseases) and limitations in activities and pain in elderly patients with knee or hip OA using a comprehensive inventory of comorbidity.

Methods

A cross-sectional cohort study was conducted, in which 288 elderly patients with hip or knee osteoarthritis were included. Apart from demographic and clinical data, information about comorbidity, limitations in activities (WOMAC, SF-36 and timed walking test) and pain (VAS) was collected by questionnaires and tests. Statistical analyses included descriptive statistics, multivariate regression techniques, t-tests and one-way ANOVA.

Results

Almost all patients suffered from at least one comorbid disease, with cardiac diseases, diseases of eye, ear, nose, throat and larynx, other urogenital diseases and endocrine/metabolic diseases being most prevalent. Morbidity count and severity index were associated with more limitations in activities and with more pain. The presence of most of the moderate or severe diseases and obesity was associated with limitations in activities or with pain.

Conclusion

The results of this study emphasize the importance of comorbidity in the rehabilitation of elderly patients with osteoarthritis of the hip or knee. Clinical practitioners should be aware of the relationship of comorbidity with functional problems in OA patients.

Physical disability due to musculoskeletal conditions

Musculoskeletal conditions (MSC) are common throughout the world and their impact on individuals is diverse and manifold. Knowledge of the determinants for disability and of strategies for prevention and rehabilitation management according to the scientific evidence is critical for reducing the burden of MSC. The first section of this chapter reviews the evidence for common determinants of functioning and disability in patients with MSC. We have focussed on environmental factors (EF) and personal factors (PF) and have structured them according to the International Classification of Functioning, Disability and Health (ICF) framework. The second section discusses prevention strategies. Generally, prevention needs to address those EF and PF that were presented in the first section. The final section describes modern principles of rehabilitation and reviews the evidence for specific rehabilitation interventions.