Determinants of Self-Report Outcome Measures in People With Knee Osteoarthritis

What is the Relationship Between Patients’ And Clinicians’ Reports of the Outcomes of Elective Surgery?

Objectives

To identify studies in which patients’ and clinicians’ reports of health status and complications of one of four elective operations - hip and knee replacement, varicose vein surgery and groin hernia repair - are reported, and to describe the associations that have been reported between clinicians’ and patients’ reports.

Methods

Systematic search of several bibliographic databases and review of citations of articles meeting inclusion criteria. A narrative summary of the findings was conducted.

Results

Most of the 62 studies of health status identified were for hip (23) or knee (33) disease. The literature on complications was even more limited with 12 studies of surgical site infection, one for urinary tract infection and none for lower respiratory tract infections. Procedure-specific complications were restricted to one for arthroplasties and three for hernia repair. Despite considerable variation in the findings of studies, some clear patterns emerge, albeit they are largely based on arthroplasty. Patients’ and clinicians’ views of health status generally correlate moderately (0.5-0.6) when both are reporting on the same dimension of health status. Inevitably this is confined to disability, though patients’ and clinicians’ reports of symptoms are also moderately correlated. In contrast, comparisons of different dimensions, such as patients’ reports of disability and clinicians’ reports of impairment, result in poor correlation (0.3). There is huge variation in the way postoperative complications are measured which limits the extent to which an overview can be undertaken. Despite that, moderate to strong correlations have been reported between patients’ and clinicians’ views of complications.

Conclusions

Patients’ views of their level of disability reflect clinicians’ views and can be relied upon to assess this dimension of health status. In addition, patients are the ‘gold standard’ judges of symptoms and quality of life. Given these findings, clinicians, provider managers, commissioners and politicians can be confident that patients’ reports provide an accurate indication of the outcome of elective surgery.

How Hand Osteoarthritis, Comorbidity, and Pain Interact to Determine Functional Limitation in Older People: Observations From the European Project on OSteoArthritis Study

OBJECTIVE

To examine the role of comorbidity and pain in the associations of hand osteoarthritis (OA) with self-reported and performance-based physical function in a general population of elderly persons.

METHODS

We studied data from 2,942 participants ages 65-85 years in the European Project on OSteoArthritis, a collaborative observational study of 6 European cohorts (from Germany, Italy, The Netherlands, Spain, Sweden, and the UK). Outcome measures included self-reported physical function of the hands measured by the AUStralian/CANadian Osteoarthritis Hand Index (AUSCAN) for hand OA physical function subscale and performance-based grip strength measured using a strain gauge dynamometer.

RESULTS

Comorbidity was not a confounder in the association of hand OA with self-reported and performance-based functional limitations, while the role of pain as a mediator was confirmed. Anxiety, depression, stroke, and osteoporosis were associated with AUSCAN scores reflecting more impairment. Depression and osteoporosis were associated with less grip strength.

CONCLUSION

Although comorbidity was decidedly and independently associated with hand functional limitation, it had no effect on the relationship of hand OA with physical function. Hand OA was found to be associated with both self-reported and performance-based physical function impairment; the association was found to be partially mediated by pain, which reduced its impact.

Hip Abductor Strengthening Improves Physical Function Following Total Knee Replacement: One-Year Follow-Up of a Randomized Pilot Study

BACKGROUND

Total knee replacement (TKR) is the commonest surgical procedure for patients with severe pain and impaired physical function following end stage knee osteoarthritis. The hip abductors are well renowned in stabilization of the trunk and hip during walking, maintaining the lower limb position, and transferring the forces from the lower limbs to the pelvis.

OBJECTIVE

To assess the efficacy of hip abductor strengthening exercise on functional outcome using performance based outcome measures following total knee replacement.

METHODS

An observer blinded randomized pilot trial design was conducted at Manipal hospital, Bangalore, India. Participants designated for elective TKR were randomized to experimental group hip abductor strengthening along with standard rehabilitation (n=10) or control group standard rehabilitation alone (n=10). Participants followed for one year to assess physical function using performance based outcomes, such as timed up and go test, single leg stance test, six minute walk test, knee extensor strength and hip abductor strength.

RESULT

Eighteen participants with a mean age of 63.1 ± 5.5 years (8 Males and 10 Females) completed the study. Improvement in hip abduction strength, single leg stand test was superior in hip abductor strengthening group at 3 months and 1 year when compared to standard rehabilitation alone.

CONCLUSION

Hip abductor strengthening showed superior improvements in single leg stance test and six minute walk test. Hip abductor strengthening exercises has the potential to improve physical function following total knee replacement.

Mediating role of body mass index in knee osteoarthritis

Objective

This study explores the role of knee circumference, body mass index (BMI), and range of motion (ROM) in predicting knee osteoarthritis (KOA). The objective is to elucidate the mediating role of BMI in influencing the relationship between age, knee circumference and pain in knee osteoarthritis, as measured with the help of the knee outcome survey (KOS) questionnaire.

Methods

The design used in this study was causal comparative. The study consisted of 66 patients with symptomatic KOA and 60 matched asymptomatic individuals.

Result

BMI was significantly and positively correlated with both pain and knee girth for the symptomatic KOA group. This finding signifies a relationship between KOA and other indicators, such as age and knee circumference.

Conclusions

The results of the study would indicate an important milestone in clinical rehabilitation, especially for physical therapists, enabling them to plan, modify, and design interventions to improve the health status of KOA patients.

Efficacy of pulsed Nd:YAG laser in the treatment of patients with knee osteoarthritis: a randomized controlled trial

The purpose of this study was to investigate the effects of pulsed Nd:YAG laser plus glucosamine/chondroitin sulfate (GCS) in patients with knee osteoarthritis (KOA) by examining changes in pain and knee function, as well as synovial thickness (ST) and femoral cartilage thickness (FCT). Sixty-seven male patients participated, with a mean (SD) age of 53.85 (4.39) years, weight of 84.01 (4.70) kg, height of 171.51 (3.96) cm, and BMI of 28.56 (1.22). Group 1 was treated with high-intensity laser therapy (HILT), GCS, and exercises (HILT + GCS + EX). Group 2 was treated with GCS plus exercises (GCS + EX), and group 3 received placebo laser plus exercises (PL + EX). The outcomes measured were pain level and functional disability using the visual analog scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), respectively. ST and FCT were measured by ultrasound examination. Statistical analyses were performed to compare differences between baseline and after 6 weeks of treatment and then after 3 months of follow-up. Statistical significance was set at p < 0.05. VAS and WOMAC were significantly decreased in all groups after 6 weeks, with nonsignificant differences between 6 weeks and 3 months of follow-up. ST was significantly decreased in the HILT + GCS + EX group posttreatment, with nonsignificant decreases in the GCS + EX and PL + EX groups, as well as nonsignificant differences to FCT in all groups. Overall, pulsed Nd:YAG laser combined with GCS and exercises was more effective than GCS + EX and exercises alone in the treatment of KOA patients.

Associations Between Fat Mass, Lean Mass, and Knee Osteoarthritis: The Fifth Korean National Health and Nutrition Examination Survey (KNHANES V)

As little is known about the associations between body composition (fat mass and lean mass) and knee OA, especially regarding body parts (upper body and lower limbs), the purpose of this study was to identify the association between the former and the prevalence of the latter according to body parts. This study was designed as a cross-sectional analysis, with 4194 people (1801 men and 2393 women) from the fifth Korean National Health and Nutrition Examination Survey (KNHANES V, 2010-2011) included. Body composition (fat mass and lean mass) was measured by using dual-energy X-ray absorptiometry, and knee OA was diagnosed based on the level of Kellgren-Lawrence grade. In multivariate logistic regression analysis, upper body composition was not significantly correlated with radiographic knee OA (P > 0.05), while participants with higher lean mass of lower limbs were less likely to have radiographic knee OA (aOR 0.57; 95 % CI 0.32-0.99). In stratified analysis, participants with higher lean mass of lower limbs were less likely to have a radiographic knee OA in 40-54 kg (P for trend = 0.05) and 55-70 kg stratum (P for trend = 0.03), while this trend slightly attenuated in 70-85 kg stratum (P for trend = 0.15). In conclusion, the increase in lean mass of lower limbs is inversely related to the prevalence of knee OA while upper body composition is not. This study suggests that the lean mass of lower limbs might be associated with reduction in the risk of knee OA.

Evaluation of psychometric properties of Tinetti performance-oriented mobility assessment scale in subjects with knee osteoarthritis

Objective:

The objective of this study was to determine the psychometric properties of the Tinetti Performance-Oriented Mobility Assessment (POMA) scale to measure balance and gait impairments in individuals with knee osteoarthritis (OA).

Methods:

A convenient sample of 25 individuals with bilateral OA knee were recruited. The convergent validity was determined by correlation analysis between scores of Berg Balance Scale (BBS) with balance subscale (POMA-B) and the Timed Up and Go Test (TUGT) with gait subscale (POMA-G). The intrarater reliability [intraclass correlation coefficient (ICC 3,1)], the Bland–Altman plots limits of agreement (LOA), the standard error of measurement (SEM), minimum detectable change (MDC) and ceiling/floor effects were determined.

Results:

Score of BBS was significantly correlated with POMA-B scores, r_s = 0.63, p = 0.001, whereas TUGT showed a negative correlation with POMA-G, r_s = −0.481, p = 0.020, showing moderate convergent validity. ICC results of the total POMA scale (POMA-T), POMA-B, and POMA-G were 0.96, 0.93, and 0.96, respectively, indicating high test retest reliability. SEM, for POMA-T, POMA-B, and POMA-G was 0.35, 0.27, and 0.35, respectively; MDC values were 0.97 for POMA-T, 0.75 for POMA-B, and 0.63 for POMA-G.

Conclusion:

The findings indicate that the POMA is a valid and reliable tool to assess balance and gait impairments in people with OA knee.

The Effect of a Self-management Program on the Quality-of-Life of Community-dwelling Older Adults with Chronic Musculoskeletal Knee Pain: A Pilot Randomized Controlled Trial

OBJECTIVES

To evaluate a 6-week self-management program on pain conducted in a mobile setting at the residences of older adult participants.

METHODS

In this single-blinded randomized controlled trial, 46 community-dwelling older adults with chronic knee pain were randomly assigned to the experimental (n = 19) and wait-list control groups (n = 27). The experimental group engaged in the 6-week program while the control group was only given some pamphlets on exercise and joint care. The pain level, physical functions, QOL, and self-efficacy of the participants in both groups were assessed at baseline, post-program, and at the 1-month follow-up session. Both baseline and post-program (or post-control-period assessment) data were analyzed.

RESULTS

The results showed that the participants in the experimental group had a higher level of self-efficacy, better performance in walking test, a higher level of quality-of-life, and less frequency of pain at the post-program follow-up as compared to the control group. The effect was maintained among the experimental group at post-4-week follow-up and further reduction in pain was detected.

CONCLUSIONS

The program appeared to be effective at improving the pain status, self-efficacy, functional performance, and quality-of-life of older adults. However, as the sample size was small, further study is suggested to investigate the effects of the program.

Longitudinal Change in Thigh Muscle Strength Prior to and Concurrent With Minimum Clinically Important Worsening or Improvement in Knee Function: Data From the Osteoarthritis Initiative

OBJECTIVE

To investigate whether a clinically relevant change in knee function in patients with or at risk for osteoarthritis (OA) of the knee is associated with concurrent or prior change in thigh muscle strength.

METHODS

Participants in the Osteoarthritis Initiative (n = 2,675 [1,485 women and 1,190 men]) with available measurements of isometric muscle strength at baseline, 2-year follow-up, and 4-year follow-up were grouped into those with greater than minimum clinically important worsening (score of ≥6 [of a possible 68] on the Western Ontario and McMaster Universities Osteoarthritis Index function subscale) between 2-year follow-up and 4-year follow-up, those with greater than minimum clinically important improvement, and those without relevant change. Changes in isometric muscle strength concurrent with function change (between 2-year follow-up and 4-year follow-up) and preceding function change (between baseline and 2-year follow-up), with 95% confidence intervals (95% CIs), were determined, and differences between groups were assessed by analysis of covariance.

RESULTS

Concurrent loss in extensor muscle strength in participants with worsening knee function during the 2-year follow-up-4-year follow-up period differed significantly from that in participants without change in knee function (-4.6% [95% CI -6.8, -2.4] and -2.2% [95% CI -3.0, -1.4], respectively; P = 0.03), as did the concurrent increase in strength among those with functional improvement (2.2% [95% CI -0.3, 4.7]; P < 0.0001). This increase in strength among subjects with improved function remained significantly different from the change in subjects with no change in function after adjustment for covariates, but was preceded by a greater loss in strength (-7.7% [95% CI -10.3, -5.0], P = 0.02) during the baseline-year 2 period compared to those without change in function during the year 2-year 4 period (-4.3% [95% CI -5.2, -3.4]). The decrease in strength during the baseline-year 2 period in those with worsening knee function during the year 2-year 4 period (-4.5% [95% CI -6.9, -2.2]) did not differ significantly from that in patients without a change in function (P = 0.87). No differences in changes in flexor muscle strength were observed between groups.

CONCLUSION

These findings suggest that there is a positive concurrent longitudinal association between change in extensor muscle strength and worsening/improvement in knee function in patients with knee OA. However, a corresponding change in thigh muscle strength preceding the change in function was not observed.

Feasibility of conducting a web-based survey of patient-reported outcomes and rehabilitation progress

Background

Web-based surveys provide an efficient means to track clinical outcomes over time without the use of clinician time for additional paperwork. Our purpose was to determine the feasibility of utilizing web-based surveys to capture rehabilitation compliance and clinical outcomes among postoperative orthopedic patients. The study hypotheses were that (a) recruitment rate would be high (>90%), (b) patients receiving surveys every two weeks would demonstrate higher response rates than patients that receive surveys every four weeks, and (c) response rates would decrease over time.

Methods

The study deaign involved a longitudinal cohort. Surgical knee patients were recruited for study participation during their first post-operative visit (n = 59, 34.9 ± 12.0 years of age). Patients with Internet access, an available email address and willingness to participate were counter-balanced into groups to receive surveys either every two or four weeks for 24 weeks post-surgery. The surveys included questions related to rehabilitation and questions from standard patient-reported outcome measures. Outcome measures included recruitment rate (participants consented/patients approached), eligibility (participants with email/participants consented), willingness (willing participants/participants eligible), and response rate (percentage of surveys completed by willing participants).

Results

Fifty-nine patients were approached regarding participation. Recruitment rate was 98% (n = 58). Eligibility was 95% (n = 55), and willingness was 91% (n = 50). The average response rate was 42% across both groups. There was no difference in the median response rates between the two-week (50%, range 0–100%) and four-week groups (33%, range 0–100%; p = 0.55).

Conclusions

Although patients report being willing and able to participate in a web-based survey, response rates failed to exceed 50% in both the two-week and four-week groups. Furthermore, response rates began to decrease after the first three months postoperatively. Therefore, supplementary data collection procedures may be necessary to meet established research quality standards.

Determination of Pain Phenotypes in Knee Osteoarthritis: A Latent Class Analysis Using Data From the Osteoarthritis Initiative

OBJECTIVE

Knee osteoarthritis (OA) is a broadly applied diagnosis that may describe multiple subtypes of pain. The purpose of this study was to identify phenotypes of knee OA, using measures from the following pain-related domains: 1) knee OA pathology, 2) psychological distress, and 3) altered pain neurophysiology.

METHODS

Data were selected from a total of 3,494 participants at visit 6 of the Osteoarthritis Initiative study. Latent class analysis was applied to the following variables: radiographic OA severity, quadriceps strength, body mass index, the Charlson Comorbidity Index (CCI), the Center for Epidemiologic Studies Depression Scale, the Coping Strategies Questionnaire-Catastrophizing subscale, number of bodily pain sites, and knee joint tenderness at 4 sites. The resulting classes were compared on the following demographic and clinical factors: age, sex, pain severity, disability, walking speed, and use of arthritis-related health care.

RESULTS

A 4-class model was identified. Class 1 (4% of the study population) had higher CCI scores. Class 2 (24%) had higher knee joint sensitivity. Class 3 (10%) had greater psychological distress. Class 4 (62%) had lesser radiographic OA, little psychological involvement, greater strength, and less pain sensitivity. Additionally, class 1 was the oldest, on average. Class 4 was the youngest, had the lowest disability, and least pain. Class 3 had the worst disability and most pain.

CONCLUSION

Four distinct pain phenotypes of knee OA were identified. Psychological factors, comorbidity status, and joint sensitivity appear to be important in defining phenotypes of knee OA-related pain.

Comparing the Predictive Value of Task Performance and Task-Specific Sensitivity During Physical Function Testing Among People With Knee Osteoarthritis

Study Design Cross-sectional cohort. Background Knee osteoarthritis (OA) is a leading cause of pain and mobility restriction. Past research has advocated the use of brief, functional tasks to evaluate these restrictions, such as the six-minute-walk test and the timed up-and-go test. Typically, only task performance (ie, walking distance, completion time) is used to inform clinical practice. Recent research, however, suggests that individual variance in how people feel while completing these tasks (ie, task sensitivity) might also have important clinical value. Objective To compare the predictive value of task performance and task-specific sensitivity in determining OA-related physical function (measured by the Western Ontario and McMaster Universities Osteoarthritis Index) and pain-related interference (measured by the Multidimensional Pain Inventory). Methods One hundred eight participants with chronic knee OA completed the six-minute-walk test and the timed up-and-go test, and reported levels of discomfort and affective response (mood) associated with each test. Results In separate regression models, both task performance and task-specific sensitivity predicted OA-related physical function and pain-related interference. A final regression model including all significant predictors showed that task-specific sensitivity (specifically, post-six-minute-walk discomfort) emerged as a unique predictor of both outcomes. Conclusion These findings highlight the value of a novel clinical assessment strategy for patients with knee OA. While clinicians commonly focus on how patients perform on standardized functional tasks, these results highlight the value of also considering levels of posttask sensitivity. Measures of task-specific sensitivity relate to Maitland's concept of pain irritability, which may be a useful framework for future research on sensitizing factors and pain-related disability. J Orthop Sports Phys Ther 2016;46(5):346-356. Epub 21 Mar 2016. doi:10.2519/jospt.2016.6311.

Validated Measures of Illness Perception and Behavior in People with Knee Pain and Knee Osteoarthritis: A Scoping Review

OBJECTIVE

To identify validated measures that capture illness perception and behavior and have been used to assess people who have knee pain/osteoarthritis.

METHODS

A scoping review was performed. Nine electronic databases were searched for records from inception through April 19, 2015. Search terms included illness perception, illness behavior, knee, pain, osteoarthritis, and their related terms. This review included English language publications of primary data on people with knee pain/osteoarthritis who were assessed with validated measures capturing any of 4 components of illness perception and behavior: monitor body, define and interpret symptoms, take remedial action, and utilize sources of help. Seventy-one publications included relevant measures. Two reviewers independently coded and analyzed each relevant measure within the 4 components.

RESULTS

Sixteen measures were identified that capture components of illness perception and behavior in the target population. These measures were originally developed to capture constructs that include coping strategies/skills/styles, illness belief, illness perception, self-efficacy, and pain behavior. Coding results indicated that 5, 11, 12, and 5 of these measures included the monitor body, define and interpret symptoms, take remedial action, and utilize sources of help components, respectively.

CONCLUSIONS

Several validated measures were interpreted as capturing some components, and only 1 measure was interpreted as capturing all of the components of illness perception and behavior in the target population. A measure that comprehensively captures illness perception and behavior could be valuable for informing and evaluating therapy for patients along a continuum of symptomatic knee osteoarthritis.

Self-Reported Disability: Association With Lower Extremity Performance and Other Determinants in Older Adults Attending Primary Care

BACKGROUND

Measurement of function usually involves the use of both performance-based and self-report instruments. However, the relationship between both types of measures is not yet completely understood, in particular for older adults attending primary care.

OBJECTIVE

The main objective of the study was to investigate the association between the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) and the Short Physical Performance Battery (SPPB) for older adults at primary care. A secondary objective was to determine the influence of sociodemographic and health-related variables on this relationship.

DESIGN

This was a cross-sectional study.

METHODS

A total of 504 participants aged 60 years and older from 18 different primary care centers underwent a one-session assessment including: sociodemographic variables, comorbidities, performance, self-reported disability, pain, depressive symptoms, and physical activity. Performance was assessed using the SPPB, and self-reported disability was assessed using the WHODAS 2.0.

RESULTS

The correlation between WHODAS 2.0 and SPPB scores was strong (r=.65). Regression analysis showed that the SPPB total score explained 41.7% of the variance in WHODAS 2.0 scores (adjusted R(2)=41.6%). A second model including the SPPB subtests (balance, gait, and sit-to-stand), depressive symptoms, number of pain sites, pain intensity, and level of physical activity explained 61.7% of the variance in WHODAS 2.0 scores (adjusted R(2)=60.4%). No model improvement was found when considering the 6 WHODAS 2.0 individual domains.

LIMITATIONS

The cross-sectional nature of the study does not allow inferences on causal relationships.

CONCLUSIONS

This study's findings confirm that self-report and performance-based measures relate to different aspects of functioning. Further study is needed to determine if primary care interventions targeting lower extremity performance and depressive symptoms improve self-reported disability.

A non-randomized clinical trial to assess the impact of nonrigid, inelastic corsets on spine function in low back pain participants and asymptomatic controls

BACKGROUND CONTEXT

Although previous studies suggest braces/corsets can reduce acute pain, no prior study has assessed back function after bracing with both self-reported and objective measures. Use of both self-reported and objective measures of spine function together may be important given evidence they assess unique aspects of function.

PURPOSE

The aim was to assess both self-reported and objective measures of spinal function before, and after, use of a nonrigid, inelastic lumbar brace.

STUDY DESIGN/SETTING

This was a non-randomized clinical trial.

PATIENT SAMPLE

The sample included acute low back pain (LBP) participants and asymptomatic controls.

OUTCOME MEASURES

Oswestry Disability Index (ODI), spinal stiffness, and muscle endurance were the outcome measures.

METHODS

Three groups were studied: -LBP/-Brace (n=19), -LBP/+Brace (n=18), and +LBP/+Brace (n=17). Both groups of braced participants were instructed to wear the brace continually for 2 weeks with the exception of bedroom and bathroom activities. Before and after the 2-week period, three measures of spinal function were performed: spinal stiffness via motorized indentation of the L3 spinous process, a modified Sorensen test (timed lumbar extension against gravity), and the ODI. Repeated measures analyses of variance were conducted for all three outcomes.

RESULTS

Among the groups, ODI scores decreased significantly for the +LBP/+Brace group (p<.001) compared with the other two groups. The +LBP/+Brace mean ODI score decreased 3.71 points (95% confidence interval [CI] 2.01-5.40) compared with the -LBP/-Brace group and decreased 3.48 points (95% CI 1.77-5.20) compared with the -LBP/+Brace group. Change scores for the Sorensen test were significantly increased in the +LBP/+Brace group (p=.037) compared with the -LBP/-Brace group (22.47s 95% CI 8.14-36.80). Spinal stiffness did not change significantly between groups.

CONCLUSIONS

This study demonstrates that lumbar function assessed by self-reported and objective measures does not worsen when nonrigid, inelastic bracing is used for short periods of time for those with, or without, back pain. These data add to the existing literature that suggests short-term use of nonrigid, inelastic bracing for acute LBP does not decrease spinal function when measured separately with subjective or objective tools.

The association between antagonist hamstring coactivation and episodes of knee joint shifting and buckling

OBJECTIVE

Hamstring coactivation during quadriceps activation is necessary to counteract the quadriceps pull on the tibia, but coactivation can be elevated with symptomatic knee osteoarthritis (OA). To guide rehabilitation to attenuate risk for mobility limitations and falls, this study evaluated whether higher antagonistic open kinetic chain hamstring coactivation is associated with knee joint buckling (sudden loss of support) and shifting (a sensation that the knee might give way).

DESIGN

At baseline, median hamstring coactivation was assessed during maximal isokinetic knee extensor strength testing and at baseline and 24-month follow-up, knee buckling and shifting was self-reported. Associations between tertiles of co-activation and knee (1) buckling, (2) shifting and (3) either buckling or shifting were assessed using logistic regression, adjusted for age, sex, knee OA and pain.

RESULTS

1826 participants (1089 women) were included. Mean ± SD age was 61.7 ± 7.7 years, BMI was 30.3 ± 5.5 kg/m(2) and 38.2% of knees had OA. There were no consistent statistically significant associations between hamstring coactivation and ipsilateral prevalent or incident buckling or the combination of buckling and shifting. The odds ratios for incident shifting in the highest in comparison with the lowest tertile of coactivation had similar magnitudes in the combined and medial hamstrings, but only reached statistical significance for lateral hamstring coactivation, OR(95%CI) 1.53 (0.99, 2.36).

CONCLUSIONS

Hamstring coactivation during an open kinetic chain quadriceps exercise was not consistently associated with prevalent or incident self-reported knee buckling or shifting in older adults with or at risk for knee OA.

Relationship between isometric thigh muscle strength and minimum clinically important differences in knee function in osteoarthritis: data from the osteoarthritis initiative

OBJECTIVE

To determine the relationship between thigh muscle strength and clinically relevant differences in self-assessed lower leg function.

METHODS

Isometric knee extensor and flexor strength of 4,553 Osteoarthritis Initiative participants (2,651 women and 1,902 men) was related to the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical function scores by linear regression. Further, groups of male and female participant strata with minimum clinically important differences (MCIDs) in WOMAC function scores (6 of 68 units) were compared across the full range of observed values and to participants without functional deficits (WOMAC score 0). The effect of WOMAC knee pain and body mass index on the above relationships was explored using stepwise regression.

RESULTS

Per regression equations, a 3.7% reduction in extensor strength and a 4.0% reduction in flexor strength were associated with an MCID in WOMAC function in women, and, respectively, a 3.6% and 4.8% reduction in men. For strength divided by body weight, reductions were 5.2% and 6.7%, respectively, in women and 5.8% and 6.7%, respectively, in men. Comparing MCID strata across the full observed range of WOMAC function confirmed the above estimates and did not suggest nonlinear relationships across the spectrum of observed values. WOMAC pain correlated strongly with WOMAC function, but extensor (and flexor) muscle strength contributed significant independent information.

CONCLUSION

Reductions of approximately 4% in isometric muscle strength and of 6% in strength per body weight were related to a clinically relevant difference in WOMAC functional disability. Longitudinal studies will need to confirm these relationships within persons. Muscle extensor (and flexor) strength (per body weight) provided significant independent information in addition to pain in explaining variability in lower leg function.

Expectation fulfilment and satisfaction in total knee arthroplasty patients using the 'PROFEX' questionnaire

BACKGROUND

Recent studies have shown that patient reported outcome measures (PROMs) may not completely reflect the satisfaction of patients with the intervention. The purpose of the study was to develop and validate a novel 'patient reported fulfilment of expectation' (PROFEX) questionnaire and to study the correlation between scores on PROMs (patient reported outcome measures such as SF-36 and WOMAC) and the post-operative fulfilment of expectations.

MATERIALS AND METHODS

In this study, a novel 20-item 'expectation' questionnaire was developed, validated and administered pre-operatively to 523 patients who underwent total knee arthroplasty for osteoarthritis. The 'fulfilment' questionnaire was administered one year following the operation. Physician-reported (Knee Society Scores) and patient-reported (WOMAC, SF-36) outcome measures were also administered.

RESULTS

Both components of PROFEX questionnaire were found to have good reliability and internal consistency. No significant correlation existed between post-operative fulfilment scores and the 'improvement' scores of WOMAC, SF-36 and Knee Society scores. Lower pre-operative expectations were associated with higher post-operative fulfilment scores, but the magnitude of this correlation was low.

CONCLUSIONS

The lack of correlation between the scores on PROMs and the PROFEX scores shows that the scores on the PROMs do not reflect the sense of fulfilment of the patients with the outcomes. Instruments that directly measure fulfilment of expectations are necessary to gain insight into the requirements of the patients.

Effect of preoperative neuromuscular training (NEMEX-TJR) on functional outcome after total knee replacement: an assessor-blinded randomized controlled trial

Background

Improving functional status preoperatively through exercise may improve postoperative outcome. Previous knowledge on preoperative exercise in knee osteoarthritis is insufficient. The aim of the study was to compare the difference in change between groups in lower extremity function from baseline to 3 months after Total Knee Replacement (TKR) following a neuromuscular exercise programme (NEMEX-TJR) plus a knee school educational package (KS) or KS alone.

Methods

45 patients (55–83 years, 53% male, waiting for TKR) were randomized to receive a minimum of 8 sessions of NEMEXTJR plus 3 sessions of KS or 3 sessions of KS alone. Function was assessed with the Chair Stand Test (CST, primary endpoint) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales focusing on daily living function (ADL) and pain (secondary endpoints). Assessments were performed immediately before and after the intervention, and at 6 weeks, 3 months and 12 months after surgery by a physiotherapist, blinded to group allocation.

Results

After intervention before surgery we observed a small improvement for primary and secondary endpoints in both groups, which did not differ significantly between groups: comparing the exercise to the control group the treatment effect for the CST was −1.5 seconds (95% CI: −5.3, 2.2), for KOOS ADL and KOOS pain the treatment effect was 1.3 points (−10.1, 12.8) and −2.3 (−12.4, 7.9) respectively. At 3 months after surgery we observed a small improvement in the primary endpoint in the control group and a significant improvement in the secondary endpoints in both exercise and control groups, which did not differ significantly between groups: comparing the exercise group to the control group the treatment effect in the CST was 2.0 seconds (−1.8, 5.8), for KOOS ADL and KOOS pain the treatment effect was −4.9 points (−16.3, 6.5) and −3.3 points (−13.5, 6.8) respectively.

Conclusions

A median (IQR) of 10 (8, 14) exercise sessions before surgery showed an additional small but non-significant improvement in all functional assessments compared to patient education alone. These benefits were not sustained after TKR. Our trial doesn’t give a conclusive answer to whether additional preoperative exercise on postoperative functional outcomes is beneficial.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-015-0556-8) contains supplementary material, which is available to authorized users.

The assessment of outcome after total knee arthroplasty: are we there yet?

The routine use of patient reported outcome measures (PROMs) in evaluating the outcome after arthroplasty by healthcare organisations reflects a growing recognition of the importance of patients' perspectives in improving treatment. Although widely embraced in the NHS, there are concerns that PROMs are being used beyond their means due to a poor understanding of their limitations. This paper reviews some of the current challenges in using PROMs to evaluate total knee arthroplasty. It highlights alternative methods that have been used to improve the assessment of outcome.

Knee arthroplasty with a medial rotating total knee replacement. Midterm clinical findings: a district general experience of 38 cases

BACKGROUND

The Medial Rotating Knee replacement (MRK) was first used in 1994, reporting high rates of satisfaction. It is designed to replicate natural knee kinematics and improve stability and function. There are limited studies on the mid-term clinical outcomes, in particular in a district general hospital (DGH) environment. This is the first study that we are aware of that evaluates the learning curve of the implementation of this knee system in this environment.

PATIENTS/METHOD

Between 2007 and 2009 we performed 38 consecutive MRK replacements (MAT ORTHO, UK) in 36 patients. The mean follow-up was four years. Patients were evaluated clinically, using OKS and patient questionnaire and radiographically (good/acceptable/poor) to assess outcome.

RESULTS

Mean age was 73.0 years. Mean pre-operative OKS was 17.7 (range 8-29), which rose to 38.1 (range 23-48) at latest follow up (p<0.005). Overall 71% of the patients were either satisfied (29%) or very satisfied (42%). 81% felt an improvement of the ability to go up or down stairs and 92% felt stable. All poor radiographic and the majority of acceptable outcomes were experienced in the first 50% of cases.

CONCLUSION

The MRK can be successfully implanted in a DGH environment. It improves pain and function comparably to standard TKRs, however, subjective improvement may be higher. Radiographic evaluation shows an acceptable learning curve.

LEVEL OF EVIDENCE

Level IV case series.

Effects of exercise therapy on walking ability in individuals with knee osteoarthritis: a systematic review and meta-analysis of randomised controlled trials

Objective:

To examine the effect of exercise therapy on the walking ability of individuals with knee osteoarthritis.

Data sources:

Randomised clinical trials (RCTs) were identified by searching through PubMed, Cochrane Central Register of Controlled Trials, Physiotherapy Evidence Database, and Cumulative Index to Nursing and Allied Health Literature. All literature published to October 2014 were included in the search.

Review methods:

Data were collected from RCTs that compared the effects of exercise therapy on walking ability with the effects of no intervention or psychoeducational intervention in participants with knee osteoarthritis. The outcome data on the total distance walked (6-minute walk test); the amount of time spent walking (the time to walk arbitrary distances); and gait velocity were obtained and analysed. Standardized mean differences (SMDs) and 95% confidence intervals (CIs) were calculated.

Results:

Twenty-eight RCTs were identified. Meta-analysis provided very-low-quality evidence that exercise therapy increased the total distance walked in the 6-minute walk test, in comparison with the effects of the control interventions (SMD = 0.44, 95% CI 0.27 to 0.60). Meta-analysis also provided low- or moderate-quality evidence that the amount of time spent walking and gait velocity were improved more by exercise therapy than by the control interventions (the amount of time spent walking: SMD = −0.50, 95% CI −0.70 to −0.30; gait velocity: SMD = 1.78, 95% CI 0.98 to 2.58).

Conclusion:

In individuals with knee osteoarthritis, exercise therapy can improve the amount of time spent walking, gait velocity, and maybe the total distance walked.

Validation of the Animated Activity Questionnaire (AAQ) for patients with hip and knee osteoarthritis: comparison to home-recorded videos

A recently developed computerized Animated Activity Questionnaire (AAQ) uses video animations to measure limitations in basic daily activities in patients with hip or knee osteoarthritis (OA). The AAQ is less time and money consuming than performance-based tests and less burdensome for patients. Compared to patient-reported outcome measurements, the AAQ is less influenced by the perception of the patient. Previous validation studies of the AAQ showed promising results. Since the AAQ purports to measure activity limitations in real-life situations, this study aims to establish the construct validity of the AAQ by comparing the AAQ to home-recorded videos. Home-recorded videos of eleven basic activities performed by 22 OA patients were transformed into scores and subsequently correlated with the AAQ, the Hip disability and Knee injury Osteoarthritis Outcome Score (H/KOOS), and three performance-based tests (Stair Climbing Test, Timed Up and Go test, and the 30 s Chair Stand Test). The AAQ was expected to correlate highly with the home-recorded videos and the performance-based tests, and moderately with the H/KOOS. As hypothesized, the AAQ correlated highly with the home-recorded videos and performance-based tests (0.83 and, 0.73 respectively), but also unexpectedly highly with the H/KOOS (0.79). In conclusion, since the AAQ correlates highly with home-recorded videos, it seems to have potential as a measurement tool to assess limitations in activities close to the real-life situation, but this should be confirmed in a larger sample of patients.

Osteoarthritis year in review 2014: rehabilitation and outcomes

OBJECTIVE

To highlight research studies examining rehabilitation for hip and knee osteoarthritis (OA), as well as the outcome measures used to assess treatment efficacy, published in 2013.

DESIGN

A systematic search was performed in Medline, CIHAHL and Embase databases from January to December 2013. The search was limited to 2013, human studies, and English. Rehabilitation intervention studies included were prospective controlled designs. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to evaluate the quality of evidence. First, individual articles were rated for quality. Second, articles were grouped based on outcome: OA disease markers, pain, physical function (self-reported, performance), and health.

RESULTS

Of 503 titles reviewed, 36 studies were included. The outcome measures related to OA disease markers were organized into subthemes of anthropometrics, biomechanics and physiology. The quality of evidence was of moderate, high, and low quality for anthropometric, biomechanical and physiological measures respectively. These studies supported the use of diet for weight loss combined with exercise. Bodies of evidence that showed the efficacy of exercise and passive strategies (thermal/electrical modalities, traction, manual therapy) for reducing pain were of low and moderate quality respectively. The evidence supporting diet and exercise, physiotherapy, and passive strategies to improve physical function was of moderate quality. Evidence supporting exercise to improve psychological factors was of moderate quality.

CONCLUSIONS

Exercise combined with diet for weight loss should be the mainstays of rehabilitation for people with knee and hip OA to provide benefit to OA disease markers, pain, physical function, and health.

Sex differences in patients with different stages of knee osteoarthritis

OBJECTIVE

To quantify the differences in physical impairments and in performance-based measures and patient-reported outcomes in men and women seeking nonoperative management of symptomatic moderate knee osteoarthritis (OA) and those with symptomatic end-stage knee OA scheduled for total knee arthroplasty compared with healthy controls.

DESIGN

Cross-sectional analysis of individuals referred to physical therapy, community participants, and subjects from a 2-year longitudinal study.

SETTING

University research department.

PARTICIPANTS

Cross-sectional analysis of participants (N=289) consisting of a moderate OA group (n=83), a severe OA group (n=143), and a healthy control group (n=63).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Quadriceps strength, timed Up and Go test, stair-climbing test, 6-minute walk test, Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS), and Physical Component Summary (PCS) of the Medical Outcomes Study 36-Item Short-Form Health Survey.

RESULTS

Women had worse scores than men for physical impairment and performance-based measures (P<.001). In the moderate OA group, women had significantly lower KOS-ADLS (P=.007) and PCS (P=.026) scores than men, with no differences seen between sexes in the other 2 groups for patient-reported measures.

CONCLUSIONS

Differences between women and men with knee OA on physical impairments and performance-based measures are not echoed in the differences seen in patient-reported measures. These measures signal different domains of knee function in patients with knee OA and should be used as part of a comprehensive functional evaluation.

Changes in self-reported disability after performance-based tests in obese and non-obese individuals diagnosed with osteoarthritis of the knee

PURPOSE

The purposes of this study are three-fold: (1) To examine whether the WOMAC questionnaire should be obtained before or after performance-based tests. (2) To assess whether self-reported disability scores before and after performance-based tests differ between obese and non-obese individuals. (3) To observe whether physical activity and BMI predict self-reported disability before and after performance based tests.

METHODS

A longitudinal study included thirty one participants diagnosed with knee osteoarthritis (OA) using the Kellgren-Lawrence Scale by an orthopedic surgeon.

RESULTS

All WOMAC scores were significantly higher after as compared to before the completion of performance-based tests. This pattern of results suggested that the WOMAC questionnaire should be administered to individuals with OA after performance-based tests. The obese OA was significantly different compared to the non-obese OA group on all WOMAC scores. Physical activity and BMI explained a significant proportion of variance of self-reported disability.

CONCLUSION

Obese individuals with knee OA may over-estimate their ability to perform physical activities, and may under-estimate their level of disability compared to non-obese individuals with knee OA. In addition, self-reported physical activity seems to be a strong indicator of disability in individuals with knee OA, particularly for individuals with a sedentary life style. Implications for Rehabilitation Osteoarthritis is a progressive joint disabling condition that restricts physical function and participation in daily activities, particularity in elderly individuals. Obesity is a comorbidity commonly associated with osteoarthritis and it appears to increase self-reported disability in those diagnosed with osteoarthritis of the knee. In a relatively small sample, this study recommends that rehabilitation professionals obtain self-report questionnaires of disability after performance-based tests in obese individuals with osteoarthritis of the knee as they are more likely to give an accurate representation of their level of ability at this time.

The avoidance model in knee and hip osteoarthritis: a systematic review of the evidence

The avoidance model in patients with knee and hip osteoarthritis (OA) hypothesizes that pain and psychological distress lead to avoidance of activities, and thereby to muscle weakness and activity limitations. This paper systematically reviews the scientific evidence for the validity of this avoidance model. A qualitative data synthesis was used to identify levels of evidence. Sixty studies were included. In knee OA, strong evidence was found that avoidance of activities is associated with activity limitations via muscle weakness (mediation by muscle weakness), strong evidence was found for an association between muscle weakness and activity limitations, and weak evidence was found that pain and psychological distress are associated with muscle weakness via avoidance of activities (mediation by avoidance). In hip OA, weak evidence was found for mediation by muscle weakness; and strong evidence was found for an association between muscle weakness and activity limitations. More research is needed on the consecutive associations between pain or psychological distress, avoidance of activities and muscle weakness, and to confirm causal relationships.

Patient-oriented and performance-based outcomes after knee autologous chondrocyte implantation: a timeline for the first year of recovery

CONTEXT

It is well established that autologous chondrocyte implantation (ACI) can require extended recovery postoperatively; however, little information exists to provide clinicians and patients with a timeline for anticipated function during the first year after ACI.

OBJECTIVE

To document the recovery of functional performance of activities of daily living after ACI.

PATIENTS

ACI patients (n = 48, 29 male; 35.1 ± 8.0 y).

INTERVENTION

All patients completed functional tests (weight-bearing squat, walk-across, sit-to-stand, step-up/over, and forward lunge) using the NeuroCom long force plate (Clackamas, OR) and completed patient-reported outcome measures (International Knee Documentation Committee Subjective Knee Evaluation Form, Lysholm, Western Ontario and McMaster Osteoarthritis Index [WOMAC], and 36-Item Short-Form Health Survey) preoperatively and 3, 6, and 12 mo postoperatively.

MAIN OUTCOME MEASURES

A covariance pattern model was used to compare performance and self-reported outcome across time and provide a timeline for functional recovery after ACI.

RESULTS

Participants demonstrated significant improvement in walk-across stride length from baseline (42.0% ± 8.9% height) at 6 (46.8% ± 8.1%) and 12 mo (46.6% ± 7.6%). Weight bearing on the involved limb during squatting at 30°, 60°, and 90° was significantly less at 3 mo than presurgery. Step-up/over time was significantly slower at 3 mo (1.67 ± 0.69 s) than at baseline (1.49 ± 0.33 s), 6 mo (1.51 ± 0.36 s), and 12 mo (1.40 ± 0.26 s). Step-up/over lift-up index was increased from baseline (41.0% ± 11.3% body weight [BW]) at 3 (45.0% ± 11.7% BW), 6 (47.0% ± 11.3% BW), and 12 mo (47.3% ± 11.6% BW). Forward-lunge time was decreased at 3 mo (1.51 ± 0.44 s) compared with baseline (1.39 ± 0.43 s), 6 mo (1.32 ± 0.05 s), and 12 mo (1.27 ± 0.06). Similarly, forward-lunge impact force was decreased at 3 mo (22.2% ± 1.4% BW) compared with baseline (25.4% ± 1.5% BW). The WOMAC demonstrated significant improvements at 3 mo. All patient-reported outcomes were improved from baseline at 6 and 12 mo postsurgery.

CONCLUSIONS

Patients' perceptions of improvements may outpace physical changes in function. Decreased function for at least the first 3 mo after ACI should be anticipated, and improvement in performance of tasks requiring weight-bearing knee flexion, such as squatting, going down stairs, or lunging, may not occur for a year or more after surgery.

Preoperative strength training for elderly patients awaiting total knee arthroplasty

Objective. To investigate the feasibility and effects of additional preoperative high intensity strength training for patients awaiting total knee arthroplasty (TKA). Design. Clinical controlled trial. Patients. Twenty-two patients awaiting TKA. Methods. Patients were allocated to a standard training group or a group receiving standard training with additional progressive strength training for 6 weeks. Isometric knee extensor strength, voluntary activation, chair stand, 6-minute walk test (6MWT), and stair climbing were assessed before and after 6 weeks of training and 6 and 12 weeks after TKA. Results. For 3 of the 11 patients in the intensive strength group, training load had to be adjusted because of pain. For both groups combined, improvements in chair stand and 6MWT were observed before surgery, but intensive strength training was not more effective than standard training. Voluntary activation did not change before and after surgery, and postoperative recovery was not different between groups (P > 0.05). Knee extensor strength of the affected leg before surgery was significantly associated with 6-minute walk (r = 0.50) and the stair climb (r - = 0.58, P < 0.05). Conclusion. Intensive strength training was feasible for the majority of patients, but there were no indications that it is more effective than standard training to increase preoperative physical performance. This trial was registered with NTR2278.

Development and validation of the computer-administered animated activity questionnaire to measure physical functioning of patients with hip or knee osteoarthritis

BACKGROUND

Physical functioning of patients with hip or knee osteoarthritis is measured by self-report questionnaires and performance-based tests. However, performance-based tests often are not feasible.

OBJECTIVE

The aim of this study was to develop a computer-administered questionnaire (ie, the Animated Activity Questionnaire [AAQ]) to measure physical functioning in patients with hip or knee OA. By showing animations of activities, the influence of the patient's own reference frame is minimized. The AAQ measures the same aspects of physical functioning as performance-based tests do.

DESIGN

This was a development and preliminary validation (cross-sectional) study.

METHODS

A pilot version of the AAQ was developed using motion capture to analyze the movement of a person performing 7 daily activities. Different animations of the same activity were made with 2 to 5 levels of difficulty. For each activity, participants were asked to choose one animation that best corresponds to their own way of performing the activity. A preliminary validation study was performed to compare the AAQ with validated self-report questionnaires (Knee Injury and Osteoarthritis Outcome Score, Hip Disability and Osteoarthritis Outcome Score, and questionnaires on walking, stair climbing, and rising and sitting down) and performance-based tests (walking, Timed "Up & Go" Test, Timed Stair Test) in 33 patients with hip or knee osteoarthritis.

RESULTS

As expected, the AAQ showed a correlation above .70 (.79, 95% confidence interval=.61-.89) with the total score of the performance-based tests. On the subscore level, the results were partly as expected. Fifty-eight percent of the participants preferred the AAQ over self-report questionnaires and performance-based tests.

LIMITATIONS

The findings need to be replicated in larger samples of patients because the sample size of the study was rather small.

CONCLUSION

The AAQ might be a good alternative for measuring physical functioning of patients with hip or knee osteoarthritis. The AAQ can easily be adapted for use in other patient populations. However, further development and validation are needed.

Selective lateral muscle activation in moderate medial knee osteoarthritis subjects does not unload medial knee condyle

There is some debate in the literature regarding the role of quadriceps-hamstrings co-contraction in the onset and progression of knee osteoarthritis. Does co-contraction during walking increase knee contact loads, thereby causing knee osteoarthritis, or might it be a compensatory mechanism to unload the medial tibial condyle? We used a detailed musculoskeletal model of the lower limb to test the hypothesis that selective activation of lateral hamstrings and quadriceps, in conjunction with inhibited medial gastrocnemius, can actually reduce the joint contact force on the medial compartment of the knee, independent of changes in kinematics or external forces. "Baseline" joint loads were computed for eight subjects with moderate medial knee osteoarthritis (OA) during level walking, using static optimization to resolve the system of muscle forces for each subject's scaled model. Holding all external loads and kinematics constant, each subject's model was then perturbed to represent non-optimal "OA-type" activation based on mean differences detected between electromyograms (EMG) of control and osteoarthritis subjects. Knee joint contact forces were greater for the "OA-type" than the "Baseline" distribution of muscle forces, particularly during early stance. The early-stance increase in medial contact load due to the "OA-type" perturbation could implicate this selective activation strategy as a cause of knee osteoarthritis. However, the largest increase in the contact load was found at the lateral condyle, and the "OA-type" lateral activation strategy did not increase the overall (greater of the first or second) medial peak contact load. While "OA-type" selective activation of lateral muscles does not appear to reduce the medial knee contact load, it could allow subjects to increase knee joint stiffness without any further increase to the peak medial contact load.

Correlation of Self-Reported Questionnaire (KOOS) with Some Objective Measures in Primary OA Knee Patients

Purpose. Objective of the present study was to see the correlation of subjectively measured KOOS questionnaire with objectively measured 6-minute walk test (6-MWT), age, height, weight, and BMI. Participants. 251 subjects with OA knee based on American College of Rheumatology criteria. Methods. After passing inclusion and exclusion criteria, the following parameters were recorded: age, height, weight, and BMI. Then subjects were asked to fill KOOS questionnaire; then all subjects were asked to do self-paced walk for 6 minutes. Analysis. Spearman rank test was done to see the correlation. Significant level was set at P < 0.05. Results. 6-MWT had a weak correlation with KOOS-ADL (rho 0.461) and strong correlation with KOOS-symptom, KOOS-pain, and KOOS-sports and very strong correlation with KOOS-QOL. BMI had a strong correlation with KOOS-pain, KOOS-symptom, KOOS-ADL, and KOOS-sports and very strong correlation with KOOS-QOL. Weight had a weak correlation with KOOS-symptom, KOOS-ADL, and KOOS-sports and strong correlation with KOOS-pain and KOOS-QOL. All the above values were significant with P < 0.001. Conclusion. KOOS is strongly positively correlated with 6-MWT and negatively correlated with BMI. Its correlation strength has decreased with weight.

Association of body mass index with physical function and health-related quality of life in adults with arthritis

Arthritis and obesity, both highly prevalent, contribute greatly to the burden of disability in US adults. We examined whether body mass index (BMI) was associated with physical function and health-related quality of life (HRQOL) measures among adults with arthritis and other rheumatic conditions. We assessed objectively measured BMI and physical functioning (six-minute walk, chair stand, seated reach, walking velocity, hand grip) and self-reported HRQOL (depression, stiffness, pain, fatigue, disability, quality of life-mental, and quality of life, physical) were assessed. Self-reported age, gender, race, physical activity, and arthritis medication use (covariates) were also assessed. Unadjusted and adjusted linear regression models examined the association between BMI and objective measures of functioning and self-reported measures of HRQOL. BMI was significantly associated with all functional (Ps ≤ 0.007) and HRQOL measures (Ps ≤ 0.03) in the unadjusted models. Associations between BMI and all functional measures (Ps ≤ 0.001) and most HRQOL measures remained significant in the adjusted models (Ps ≤ 0.05); depression and quality of life, physical, were not significant. The present analysis of a range of HRQOL and objective measures of physical function demonstrates the debilitating effects of the combination of overweight and arthritis and other rheumatic conditions. Future research should focus on developing effective group and self-management programs for weight loss for people with arthritis and other rheumatic conditions (registered on clinicaltrials.gov: NCT01172327).

Unilateral vs bilateral symptomatic knee osteoarthritis: associations between pain intensity and function

OBJECTIVE

The objective of this study was to determine if associations between pain distribution (unilateral vs bilateral) and measures of function (self-report vs performance-based) were influenced by knee pain intensity of the painful knee(s) in persons with moderate to severe symptomatic knee OA.

METHODS

Data from persons in the Osteoarthritis Initiative (OAI) dataset (n = 852) with symptomatic knee OA were studied. Key dependent variables were the WOMAC physical function, Knee Injury and Osteoarthritis Outcome Score (KOOS) quality of life, the repeated chair stand test and the 20-m walk test. In addition to covariates, the independent variables were the presence of unilateral or bilateral OA involvement (either Kellgren and Lawrence grade 3 or 4 or a grade <3) and pain category (mild, moderate or severe).

RESULTS

WOMAC physical function scores consistently showed the strongest association with pain intensity for persons with unilateral vs bilateral knee pain. For example, in persons with unilateral severe knee pain, WOMAC scores averaged 19.9 (S.D. = 12.0) points while persons with bilateral knee pain with at least one knee rated as severe had WOMAC scores ranging from 25.3 to 28.9, depending on pain severity of the contralateral knee. These differences were statistically significant (P < 0.001) as was the test for trend (P = 0.001). Self-report measures generally showed larger effect sizes than performance-based measures.

CONCLUSION

Knee pain intensity influences self-report and performance-based tests differently depending on whether knee pain is unilateral or bilateral. WOMAC scores are most strongly associated with pain intensity in persons with unilateral vs bilateral pain while walking tests are least influenced by pain intensity.

The feasibility of a 3-month active rehabilitation program for patients with knee full-thickness articular cartilage lesions: the Oslo Cartilage Active Rehabilitation and Education Study

STUDY DESIGN

Case series.

OBJECTIVES

To evaluate the feasibility of an active rehabilitation program for patients with knee full-thickness articular cartilage lesions.

BACKGROUND

No studies have yet evaluated the effect of active rehabilitation in patients with knee full-thickness articular cartilage lesions or compared the effects of active rehabilitation to those of surgical interventions. As an initial step, the feasibility of such a program needs to be described.

METHODS

Forty-eight patients with a knee full-thickness articular cartilage lesion and a Lysholm score below 75 participated in a 3-month active rehabilitation program consisting of cardiovascular training, knee and hip progressive resistance training, and neuromuscular training. Feasibility was determined by monitoring adherence to the program, clinical changes in knee function, load progression, and adverse events. Patients were tested before and after completing the rehabilitation program by using patient-reported outcomes (Knee injury and Osteoarthritis Outcome Score, International Knee Documentation Committee Subjective Knee Evaluation Form 2000) and isokinetic muscle strength and hop tests. To monitor adherence, load progression, and adverse events, patients responded to an online survey and kept training diaries.

RESULTS

The average adherence rate to the rehabilitation program was 83%. Four patients (9%) showed adverse events, as they could not perform the exercises due to pain and effusion. Significant and clinically meaningful improvement was found, based on changes on the International Knee Documentation Committee Subjective Knee Evaluation Form 2000, the Knee injury and Osteoarthritis Outcome Score quality of life subscale, isokinetic muscle strength, and hop performance (P<.05), with small to large effect sizes (standardized response mean, 0.3-1.22).

CONCLUSION

The combination of a high adherence rate, clinically meaningful changes, and positive load progression and the occurrence of only a few adverse events support the potential usefulness of this program for patients with knee full-thickness cartilage lesions. This study was registered with the public trial registry ClinicalTrials.gov (NCT00885729).

LEVEL OF EVIDENCE

Therapy, level 4.

Perception and presentation of function in patients with unilateral versus bilateral knee osteoarthritis

OBJECTIVE

Lower extremity functional performance and perception of functional abilities influence clinical management in people diagnosed with unilateral or bilateral knee osteoarthritis (OA). The purpose of this study was to determine if there were differences in perception of function and performance during functional tasks between individuals with unilateral and bilateral knee OA.

METHODS

The functional abilities of patients with symptomatic and radiographic diagnosed unilateral (n = 84) or bilateral (n = 68) knee OA were evaluated with self-report measures and performance-based tests. Self-report measures included the Knee Outcome Survey, the Global Rating Scale, and the physical component of the Short Form 36 health survey; functional tests included the Timed Up-and-Go Test, the Stair Climbing Test, and the 6-Minute Walk Test. Multivariate analyses of variance were performed separately for men and women to determine if perception (self-report measures) and performance (functional tests) were dependent on the number of involved knees.

RESULTS

No significant main effects were observed in functional performance between groups for either sex. Similarly, the perception measures did not differ between groups. In general, individuals diagnosed with unilateral and bilateral knee OA both performed functional tasks and perceived their functional ability similarly.

CONCLUSION

Regardless of the number of involved knees, individuals with knee OA perform and perceive their functional ability similarly, which suggests that clinicians need to consider other factors, such as how long the disease has been progressing or how functional abilities have changed, when treating patients with knee OA.

A physiotherapist-delivered, combined exercise and pain coping skills training intervention for individuals with knee osteoarthritis: a pilot study

BACKGROUND

Osteoarthritis (OA) of the knee is associated with a number of physical and psychological impairments. Unfortunately, very few treatment strategies are capable of addressing both types of impairments concurrently. We performed a pilot, randomized controlled, proof of principle trial investigating the feasibility and effects of an intervention combining physical exercise and pain coping skills training (PCST).

METHODS

Twenty patients with a clinical and radiographical diagnosis of tibiofemoral OA were randomized to receive either 10 weeks of physiotherapist supervised exercises (lower limb strengthening and walking) combined with non-directive counseling (NDC) or the same exercise program delivered concurrently with PCST. Primary outcomes included self-reported pain and pain coping, while secondary outcomes included self efficacy and self-reported physical function.

RESULTS

Ten participants were randomized to each group and both groups exhibited significant improvements in isometric knee strength, self-reported knee pain and physical function, self efficacy for control of pain management and other arthritis symptoms. Only those in the exercise + PCST group reported statistically significant improvements in pain control coping and rational thinking. No between-group differences existed in any outcome (0.07 < p < 0.98). Based on our findings, 63 participants per group would be needed for future large-scale studies using similar outcome measures and design.

CONCLUSIONS

Our study showed that an intervention that combines exercise and PCST within the same treatment session and delivered by specially-trained physiotherapists is feasible and can improve both physical and psychological outcomes in individuals with knee OA.

LEVEL OF EVIDENCE

Level II Clinical Trials Registry number: ACTRN12609000623291.

Associations for change in physical and psychological factors and treatment response following exercise in knee osteoarthritis: an exploratory study

OBJECTIVE

Understanding how changes in physical and psychological factors following therapeutic exercise are associated with treatment outcome could have important implications for refining rehabilitation programs for knee osteoarthritis (OA). The objective of this study was to examine the association of changes in these factors with changes in pain and function after an exercise program for people with knee OA.

METHODS

In total, 152 people with knee OA completed an exercise program consisting of lower extremity strengthening, stretching, range of motion, balance and agility, and aerobic exercises. The change from baseline to the 2-month followup was calculated for physical and psychological factors, including self-reported knee instability, quadriceps strength, knee and ankle range of motion, lower extremity muscle flexibility, fear of physical activity, anxiety, and depressive symptoms. Treatment response was defined as a minimum of a 20% improvement from baseline in both a numerical knee pain rating scale and the Western Ontario and McMaster Universities Osteoarthritis Index physical function scale. The association of each factor with treatment response was examined with logistic regression mutually adjusted for age, sex, body mass index, radiographic severity, and exercise group.

RESULTS

Change in self-reported knee instability (odds ratio [OR] 1.67 [95% confidence interval (95% CI) 1.13-2.47]) and fear of physical activity (OR 0.93 [95% CI 0.88-1.00]) were the only 2 factors that were significantly associated with treatment response after adjustment for covariates.

CONCLUSION

Improvement in knee instability and fear of physical activity were associated with increased odds of a positive treatment response following therapeutic exercise in subjects with knee OA.

A nested case-control analysis of self-reported physical functioning after total knee replacement surgery in the 45 and Up Study Cohort

OBJECTIVES

The rate of total knee arthroplasty surgery (TKA) is rising in Australia despite varying impacts of TKA on physical function (PF) in population-based studies. There are potentially modifiable risk factors that could enhance PF after TKA, so we evaluated (1) the levels of PF in persons with TKA and the rest of the population, (2) potentially modifiable characteristics of those reporting poor PF after TKA.

DESIGN

Nested case-control study.

SETTING

Population-based cohort study in New South Wales, Australia.

PARTICIPANTS

Members of a large (n=267 151) cohort study recruited by a self-completed, mailed questionnaire from 2006 to 2008. After exclusions (for hip arthroplasty, partial TKA, missing important variables and mismatching TKA status between self-reported and hospital record data), this study included 205 148 participants.

PRIMARY AND SECONDARY OUTCOMES

Primary outcome, Medical Outcomes Study Physical Function scale (MOS-PF). Secondary outcome, dispensings of analgesics or anti-inflammatory drugs.

RESULTS

We found 2916 TKA participants and 202 232 participants with no TKA (confirmed across datasets). Persons with TKA had a lower MOS-PF (59.9, 95% CI 58.5 to 60.6) than those without TKA (83.8, 95% CI 83.7 to 83.9). In the matched analysis, the TKA group had a lower MOS-PF (59.9, 95% CI 59.9 to 62.4) than those without TKA (68.4, 95% CI 67.8 to 69.0). In persons with TKA, lower levels of MOS-PF were associated with low self-rated health, high psychological distress, comorbidity, greater age, recent treatment for osteoarthritis and use of paracetamol. Women had an MOS-PF that was 11.6 points (95% CI 9.5 to 13.8) lower than men.

CONCLUSIONS

Several modifiable risk factors have been identified to influence PF in persons receiving TKA, with notable differences between sexes. The importance of these risk factors should be examined in incident TKA to test if early identification and intervention for individuals can improve outcomes.

A performance based patient outcome score for active patients following total knee arthroplasty

OBJECTIVE

The aim of this study was to develop and validate a user friendly performance based knee outcome score for use in active patients undergoing TKA surgery.

DESIGN

We prospectively studied a cohort of 50 subjects without any knee symptoms, and 50 patients who underwent TKA for osteoarthritis (OA). The patients were assessed pre- and postoperatively. SF-36 and WOMAC were concurrently administered for comparison. Patients completed seven physical tasks of the finalised outcome instrument which were objectively assessed and scored.

RESULTS

The mean functional score was 31.7 in the normal subjects. The mean functional score improved postoperatively from 10.0 to 17.7 (P < 0.001) in the TKA group. Our results confirm that the performance based score has a high test-retest reliability (intra-class correlation coefficient (ICC) of 0.89), internal consistency (Cronbach's alpha 0.84) and construct validity showing expected correlations with relevant components of the WOMAC and SF-36 scores. The responsiveness as measured by the effect size compared favourably with the same relevant components of the SF-36 and WOMAC.

CONCLUSIONS

Our performance based knee function score is a reliable dimension specific tool to detect change in musculoskeletal function after TKA. It complements existing self-reported outcome tools in facilitating a comprehensive assessment of patients following TKA.

Muscle impairments in patients with knee osteoarthritis

Context:

Muscle impairments associated with knee osteoarthritis (OA) are the primary underlying cause of functional limitations. Understanding the extent of muscle impairments, its relationship with physical function and disease progression, and the evidence behind exercise therapy that targets muscle impairments is crucial.

Evidence Acquisition:

An electronic search for relevant articles using MEDLINE and CINHAL databases up to September 2011 was performed. In addition to the electronic search, retrieved articles were searched manually for relevant studies.

Results:

Quadriceps, hamstrings, and hip muscles are significantly impaired in subjects with knee OA compared with age-matched controls. Muscle strength, especially quadriceps, is a major determinant of both performance-based and self-reported physical function. Whether stronger quadriceps is protective against knee OA onset and progression is not clear. Exercise therapy, including global and targeted resistance training, is effective in reducing pain and improving function in subjects with knee OA.

Conclusions:

Subjects with knee OA have significant muscle impairments. These muscle impairments affect physical function and should be targeted in therapy. Further research is needed to explore the relationship between quadriceps strength and knee OA initiation and progression and to determine the optimal exercise prescription that augments outcomes in this patient population.

Comparing the lower limb tasks questionnaire to the Western Ontario and McMaster Universities Osteoarthritis Index: agreement, responsiveness, and convergence with physical performance for knee osteoarthritis patients

OBJECTIVE

To compare the Lower Limb Tasks Questionnaire (LLTQ) with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) in terms of agreement, responsiveness, and convergence.

DESIGN

Cross-sectional with an exploratory repeated-measures subsample analysis.

SETTING

Community-based seniors' centers and arthritis clinics.

PARTICIPANTS

Individuals with symptomatic knee osteoarthritis (N=76) participated, with a subsample of 18 participants contributing to the pre- and postarthroplasty subanalysis.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

Bland and Altman plots of agreement with 95% limits of agreement, statistical responsiveness, and standardized response mean (SRM) were calculated for LLTQ and WOMAC subscales. Both t tests and Wilcoxon rank-sum tests were used to examine changes in pre- and postarthroplasty self-reported function, 50-ft walk speed, stair ascent/descent speed, and isometric quadriceps strength.

RESULTS

The agreement (bias) of the LLTQ activities of daily living (ADL) subscale when compared with the WOMAC physical function (PF) subscale was 1%±10% (mean ± SD), and the 95% limits of agreement were -19% to +22%. The statistical responsiveness of the WOMAC-PF and LLTQ ADL was 1.17 and -.63, respectively. The SRMs for these scales were .90 and -.61, respectively. The WOMAC-PF scores showed a notable improvement over the first 6 weeks postarthroplasty, while LLTQ ADL scores were unchanged. The objective measures of function were all significantly worse at 6 weeks.

CONCLUSIONS

The LLTQ demonstrated adequate agreement with the WOMAC and acceptable responsiveness for use in place of the WOMAC in nonspecialized clinics. The LLTQ may more accurately represent functional status after total knee arthroplasty, but further study in larger samples is recommended.