Improvements in quadriceps sensorimotor function and disability of patients with knee osteoarthritis following a clinically practicable exercise regime

OBJECTIVE: Quadriceps sensorimotor dysfunction may be important in the pathogenesis of knee osteoarthritis (OA) and a determinant of disability. Exercise regimes can increase quadriceps strength, but whether this improves proprioception and reduces disability is uncertain. Moreover, research regimes involve protracted treatment which is clinically impracticable. METHODS: We compared quadriceps sensorimotor function and disability in 60 patients with knee OA, before and after an exercise regime, with a control group (n = 37) who did not exercise. RESULTS: Exercise improved quadriceps strength (mean change, 95% CI; 73 N, 26-19 N), voluntary activation (14%, 5-20%), knee joint position sense (0.6 degrees, 0.1-1.8 degrees), and reduced the Lequesne Index (3.5, 0.5-4) and aggregate time of four activities of daily living (8.4 s, 0.2-16.7 s). At 6 month follow-up, these improvements were maintained. The parameters of the control group were unchanged. CONCLUSIONS: These results substantiate the association between quadriceps sensorimotor dysfunction and disability, emphasizing the importance of quadriceps exercise in the management of knee OA. The regimen is relatively brief and clinically practicable, but could be adapted to make it more cost effective.     

Obese, older adults with knee osteoarthritis: Weight loss, exercise, and quality of life.

This study examined the effects of dietary weight loss and exercise on the health-related quality of life (HRQL) of overweight and obese, older adults with knee osteoarthritis. A total of 316 older men and women with documented evidence of knee osteoarthritis were randomly assigned to 1 of 4 18-month interventions: dietary weight loss, exercise, dietary weight loss and exercise, or healthy lifestyle control. Measures included the SF-36 Health Survey and satisfaction with body function and appearance. Results revealed that the combined diet and exercise intervention had the most consistent, positive effect on HRQL compared with the control group; however, findings were restricted to measures of physical health or psychological outcomes that are related to the physical self. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adaptation to disability: Applying selective optimization with compensation to the behaviors of older adults with osteoarthritis.

This research extends the use of P. B. Baltes and M. M. Baltes's (1990) theory of selective optimization with compensation (SOC) in an effort to conceptually integrate the adaptational behaviors of 248 older adults with disability arising from osteoarthritis. The authors also studied the relationship of SOC to age, illness variables, disability, illness perceptions, and support. The results highlight the variability and plasticity of older adults' efforts to manage disability, with most efforts aimed at compensation and optimization rather than selection. The benefit of using SOC to study adaptation to chronic illness and disability is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Quadriceps weakness in knee osteoarthritis: the effect on pain and disability

OBJECTIVES: (1) To determine the importance of quadriceps strength, structural change, and psychological status in terms of knee pain in the community. (2) To determine the relative importance of quadriceps function, structural change, and psychological status with respect to disability in subjects with knee pain. METHODS: 300 men and women with pain and 300 controls without pain (aged 40-79) were seen. Isometric quadriceps strength (MVC) was measured and muscle activation was assessed by twitch superimposition. Disability (Western Ontario McMaster Osteoarthritis Index (WOMAC)) and anxiety and depression were assessed (Hospital Anxiety and Depression Index (HAD)). Radiographs were obtained of the tibiofemoral and patellofemoral joints and total score for osteophyte, narrowing, and sclerosis calculated for each knee. RESULTS: Subjects with knee pain had lower voluntary quadriceps strength than those without pain (p < 0.005). Quadriceps activation was also lower (p < 0.005), but did not fully explain the reduction in strength. When analysed by multiple logistic regression: quadriceps strength (odds ratio 18.8, CI 4.8, 74.1 for MVC < or = 10 kgF); depression (odds ratio 2.4, CI 1.0, 5.5 for HAD score > or = 8); and radiographic change (odds ratio 4.1, CI 1.9, 8.6 for radiographic score > or = 4) were independently associated with pain. In those with knee pain, disability was independently associated with quadriceps strength (odds ratio 8.2, CI 1.5, 44.4 for MVC < or = 10 kgF) and depression (odds ratio 6.2, CI 2.1, 18.0 for HAD score > or = 8); but not with radiographic score. CONCLUSIONS: Quadriceps strength is strongly associated with knee pain and disability in the community, even when activation and psychological factors are taken into account. This has important therapeutic implications.     

Estimation of VO2 in older individuals with osteoarthritis of the knee and cardiovascular disease

The American College of Sports Medicine (ACSM) equation for estimating oxygen consumption (VO2) is often inappropriately applied to non-steady-state treadmill exercise. Therefore, it was the purpose of this investigation to develop an equation to estimate VO2 that could be applied to non-steady-state treadmill exercise in a population of patients with osteoarthritis of the knee, and to assess the generalizability of this equation for estimating VO2peak in patients with cardiovascular disease. Subjects for the investigation were 414 participants in the Fitness and Arthritis in Seniors Trial (FAST), and 362 patients with cardiovascular disease. Results from the FAST subjects showed that the ACSM equation was inappropriate for estimating VO2 during non-steady-state incremental treadmill walking. We developed the following equation (FAST) using speed and the interaction between speed and grade as the predictor variables during treadmill walking: VO2(ml.kg-1.min-1) = 0.0698 x speed(m.min-1) + 0.8147 x grade(%) x speed(m.min-1) + 7.533 ml.kg-1.min-1 The generalizability of the FAST equation for estimating VO2peak was evaluated in the patients with cardiovascular disease. The measured VO2peak of these patients was 23.7 +/- 0.3 ml.kg-1.min-1, whereas the VO2peak values estimated from the FAST equation and the ACSM equation were 24.1 +/- 0.3 and 33.2 +/- 0.5 ml.kg-1.min-1, respectively. No significant differences were found between the measured VO2peak and that estimated from the FAST equation. The VO2peak estimated from the ACSM equation was significantly greater than the measured VO2peak. These results suggest it is more appropriate to use the FAST equation rather than the ACSM equation to estimate VO2 in older patients with either osteoarthritis of the knee or cardiovascular disease.     

Mechanical unweighting effects on treadmill exercise and pain in elderly people with osteoarthritis of the knee

Anthropometric and biochemical research was conducted on 94 subjects with various levels of lower limb amputation. The purpose of the work was to investigate the features of obesity progression and disorders of cholesterin metabolism, as well as to develop adequate training exercises. Anthropometric research was conducted by calipermetry; the biochemical research was done by various methods to determine exempt and total cholesterin and triglycerides in the blood serum. The research establishes the frequency of obesity progression relative to the level of amputation, as well as the features of the excessive body mass. Type 11A hyperlipoproteidemia was evident. It is characterized by rapid progress of atherosclerotic vascular disease and coronary disease (CD). Cyclic and acyclic exercises were developed for prophylaxis and therapy. Anthropometric research on the determination of body fat mass was conducted on 68 subjects with various levels of lower limb amputation. The nondirect method of measuring skin folds of several parts of the body was used to determine the extent of lipogenesis. Biochemical research of cholesterin metabolism was conducted on 26 subjects with lower limb amputation (a different group). Anthropometric research revealed an increase of body fat mass directly related to the level of amputation. The largest amount of fat in the body mass was noted for the subjects with bilateral transfemoral (above-knee) amputation or transfemoral plus transtibial (below-knee) amputation. Both groups averaged 25.9%. The body fat mass increased chiefly in the subcutaneous fat. Increase of the internal fat mass was less noticeable. The frequency of obesity progression in subjects with unilateral transtibial amputation equaled 37.9%; in subjects with transfemoral amputation, 48.0%; and in subjects with bilateral transfemoral or transfemoral plus transtibial amputation, 64.2%. Young subjects demonstrated obesity progression during the first year after amputation. Biochemical research revealed changes in the cholesterin fractions typical for type 11A hyperlipoproteidemia. This type of hyperlipoproteidemia is often accompanied by atherosclerotic vascular diseases and CD. On the basis of the research and clinical observation, exercises were developed aimed at prophylaxis and treatment of the revealed changes. Exercises are described for subjects with various levels of lower limb amputation when using exercise machines and when swimming.     

Estrogen replacement therapy and worsening of radiographic knee osteoarthritis: the Framingham Study

OBJECTIVE: To examine whether estrogen replacement therapy (ERT) prevents worsening of radiographic knee osteoarthritis (OA) in elderly women. METHODS: A total of 551 women ages 63-91 years (mean age 71) in the Framingham Study were followed up from biennial examination 18 (1983-1985) to examination 22 (1992-1993). Data on postmenopausal ERT were obtained every 2 years. Subjects were classified into 3 groups according to their estrogen use at biennial examination 18: never users (n = 349), past users (n = 162), and current users (n = 40). Women received anteroposterior weight-bearing knee radiographs at examinations 18 and 22. Using the Kellgren and Lawrence criteria, global radiographic knee OA was assessed, (grade range 0-4) and individual radiographic features, such as osteophytes and joint space narrowing, were scored from 0 to 3. Worsening was defined as either development of radiographic OA that was not present at baseline (incident OA) or progression of baseline radiographic OA by > or =1 Kellgren and Lawrence grade (progressive OA). Potential confounding factors included age, body mass index, weight change, smoking, knee injury, physical activity level, and bone mineral density at the femoral neck. RESULTS: During 8 years of followup, 17.4% of knee radiographic scores worsened by 1 grade and 5.8% by 2 or 3 grades among never users of ERT. Among current estrogen users, only 11.7% of knee radiographic scores worsened by 1 grade and none worsened by more than 1 grade. After adjusting for age and other potential confounding factors, the relative risk of incident radiographic knee OA in comparison with never users of estrogen was 0.8 (95% confidence interval [95% CI] 0.5-1.4) in past users and 0.4 (95% CI 0.1-3.0) in current users. Current use of estrogen also showed a trend toward decreased risk of progressive knee OA compared with never use (odds ratio [OR] 0.5, 95% CI 0.1-2.9). When both incident and progressive radiographic knee OA cases were combined, current ERT use had a 60% decreased risk compared with never use (OR 0.4, 95% CI 0.1-1.5). CONCLUSION: This is the first prospective cohort study to examine the effects of ERT on radiographic knee OA. The results indicate that current use of ERT had a moderate, but not statistically significant, protective effect against worsening of radiographic knee OA among elderly white women. These findings corroborate those of cross-sectional studies and point further to a potential benefit of female hormones in OA.     

Radiographic assessment of knee osteoarthritis: reproducibility and sensitivity to change

OBJECTIVE: To determine the cross sectional and longitudinal reproducibility of various measures used for assessing radiographic knee osteoarthritis (OA) and to compare the sensitivity to change over a one year period of these measures. METHODS: We studied 55 patients referred to hospital with knee OA (clinical and radiographic ACR criteria). Anteroposterior radiographs at baseline and after 12 months were read by methods both qualitative (Kellgren and Lawrence grading scale, joint space narrowing scale) and quantitative (joint space width measurement at 3 different points). All qualitative methods used standardized atlases. The intraclass correlation coefficient and the graphical method of Bland and Altman were used to assess cross sectional and longitudinal reproducibility. Reproducibility was tested using 2 readers (interreader) and 2 readings for one of the readers (intrareader). Sensitivity to change was assessed using standardized response mean (SRM). RESULTS: All methods tested were shown to be reproducible both for cross sectional and longitudinal data. Intrareader was higher than interreader reproducibility for most radiographic features. Significant changes were observed after one year for methods measuring joint space narrowing. The sensitivity to change of the methods assessing joint space narrowing (joint space narrowing scale and joint space width measurement) was higher, with SRM varying from 0.37 to 0.57, than for the Kellgren and Lawrence grading system (SRM 0.19 and 0.23). CONCLUSION: These data suggest that methods measuring narrowing should be preferred as outcome measures in clinical trials or longitudinal epidemiologic studies; and show that in a particular subset of patients with very active disease, significant radiographic changes in knee OA can be detected after a one year period.     

Effects of a muscle exercise program on exercise capacity in subjects with osteoarthritis

Maximal aerobic power and muscle function have been shown to decrease with age and to be even lower in patients with osteoarthritis (OA). This study was designed to determine if subjects with OA who underwent only a muscle exercise program had improved exercise capacity and cardiovascular fitness. A maximal graded exercise test was given before and after 3 months of exercise (isometric, isotonic, and isometric force generated as a function of time contractions, three times a week). Maximal strength and the tension-time index improved significantly. Peak aerobic power increased from 15.99 +/- 3.96 mL.kg-1.min-1 to 20.34 +/- 3.29 mL.kg-1.min-1. On average, maximal walking speed increased from 2.0 +/- 0.6 mph to 2.4 +/- 0.7mph. Exercise time increased 22%, from 9.2 +/- 2.3 minutes to 11.2 +/- 2.7 minutes. There were significant reductions in submaximal heart rate (15b.min-1) and systolic blood pressure (15mmHg) after training. It would appear that the reduction in aerobic fitness of subjects with OA is secondary to their reduced muscle function. By improving muscle function, increases in exercise capacity and aerobic fitness occurred.     

Reliability of gait measurements in people with osteoarthritis of the knee

BACKGROUND AND PURPOSE: The purpose of this study was to assess the intrasession and intersession reliability of measurements of quantitative gait variables at two self-selected walking speeds. SUBJECTS: Forty-one patients with osteoarthritis in one or both knees who were referred for physical therapy participated. METHODS: Three measurements were made at 1-week intervals. The quantitative gait variables of walking speed, cadence, and stride length were measured using an 8-m electronic footswitch walkway. At each measurement, subjects were asked to walk five times at a self-selected pace that they considered to be normal and five times at a self-selected pace that they considered to be fast. RESULTS: At the normal walking speed, although intraclass correlations were consistently high for all gait variables, an additive factor within and across the first two measurements was evident even when a mean of several trials was used. At the fast walking speed, the intraclass correlations were again consistently high for all gait variables, but there were no changes within or across the measurements. CONCLUSION AND DISCUSSION: The data suggest that quantitative gait analysis is a practical objective assessment tool for persons with osteoarthritis of the knee. Gait at the fast walking speed, however, will provide the more reliable stable measure on which to evaluate the effect of therapy when compared with gait at the normal walking speed. The comparative responsiveness to change between the two walking speeds still needs to be determined.     

Risk indicators for malnutrition are associated inversely with quality of life for participants in meal programs for older adults

OBJECTIVE: To investigate the feasibility, safety and results of laparoscopic transperitoneal adrenalectomies performed with the patient supine, in patients affected by secreting and silent adrenal lesions. METHODS: Exclusion criteria were suspected adrenal primary malignancies. Fifty patients (33 women and 17 men; mean age 49.6 years, range 19-75 years) underwent 51 laparoscopic adrenalectomies (one bilateral). After complete endocrinological evaluation, computed tomography or magnetic resonance imaging, or a combination thereof, 14 non-secreting adenomas, 13 aldosterone-producing adenomas, 13 cortisol-producing adenomas, eight phaeochromocytomas (one bilateral), one androgen-secreting adenoma, and two metastases were considered eligible for adrenalectomy. In five patients, associated procedures were performed during surgery. RESULTS: The lesions ranged in size from 1.5 to 10 cm. There were no intraoperative complications and no blood transfusions were required. The postoperative course was uneventful and painless in all patients. Mean postoperative hospital stay was 2.5 days. In all hypertensive patients, significant improvement or cure of hypertension was observed at follow-up (mean 18 months). In patients with secreting adenomas, normalization of hormone concentrations was obtained after removal of the tumour. In six patients with incidentaloma, the exaggerated 17-hydroxyprogesterone response to ACTH disappeared after surgery. CONCLUSIONS: Secreting and non-secreting adrenal lesions were treated safely by laparoscopy. Relatively small incidentalomas and subclinical hormonally active tumours can be removed by laparoscopy. Early diagnosis enhances prevention and treatment.     

Risk factors for incident radiographic knee osteoarthritis in the elderly: the Framingham Study

OBJECTIVE: Knee osteoarthritis (OA) is highly prevalent, especially in the elderly. Preventive strategies require a knowledge of risk factors that precede disease onset. The present study was conducted to determine the longitudinal risk factors for knee OA in an elderly population. METHODS: A longitudinal study of knee OA involving members of the Framingham Study cohort was performed. Weight-bearing knee radiographs were obtained in 1983-1985 (baseline) and again in 1992-1993. Incident disease was defined as the occurrence of new radiographic OA (Kellgren and Lawrence grade > or = 2 on a 0-4 scale) in those without radiographic OA at baseline. Risk factors assessed at baseline and in the interim were tested in univariate and multivariate equations to evaluate their association with incident knee OA. RESULTS: Of 598 patients without knee OA at baseline (mean age 70.5 years, 63.7% women), 93 (15.6%) developed OA. After adjustment for multiple risk factors, women had a higher risk of OA than did men (adjusted odds ratio [OR] = 1.8, 95% confidence interval [95% CI] 1.1-3.1). Higher baseline body mass index increased the risk of OA (OR = 1.6 per 5-unit increase, 95% CI 1.2-2.2), and weight change was directly correlated with the risk of OA (OR = 1.4 per 10-lb change in weight, 95% CI 1.1-1.8). Physical activity increased the risk of OA (for those in the highest quartile, OR = 3.3, 95% CI 1.4-7.5). Smokers had a lower risk than did nonsmokers (for those who smoked an average of > or = 10 cigarettes/day, OR = 0.4, 95% CI 0.2-0.8). Factors not associated with the risk of OA included chondrocalcinosis and a history of hand OA. Weight-related factors affected the risk of OA only in women. CONCLUSION: Elderly persons at high risk of developing radiographic knee OA included obese persons, nonsmokers, and those who were physically active. The direction of weight change correlated directly with the risk of developing OA.     

Individual versus group therapy for obesity: Effects of matching participants to their treatment preferences.

This study examined the effects of matching participants to treatments on the basis of their preferences for either individual or group therapy for obesity. Seventy-five obese adults who expressed a clear preference for either individual or group therapy were randomly assigned to either their preferred or their nonpreferred treatment modality within a 2 (individual vs group therapy)?×?2(preferred vs nonpreferred modality) factorial design. At posttreatment, group therapy produced significantly greater reductions in weight and body mass than individual therapy, and no significant effects were observed for treatment preference or the interaction for treatment preference by type of therapy. All treatment conditions showed equivalent improvements in psychological functioning. These findings suggest that group therapy produces greater weight loss than individual therapy, even among those clients who express a preference for individual treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Arthroscopic debridement for osteoarthritis of the knee: a seven years follow-up study

We reviewed 32 knees with osteoarthritis of the knee treated by either arthroscopic debridement in association with drilling the subchondral bone or arthroscopic debridement alone and followed for 2.5 to 11 years. Eighteen knees had arthroscopic debridement and drilling the subchondral bone, and 14 knees had arthroscopic debridement alone. In the group treated with arthroscopic debridement and drilling the subchondral bone, 55.6% had good to excellent results, 22.2% had fair results, and 22.2% had poor results. In the group that had arthroscopic debridement alone, 57.2% had good to excellent results, 35.7% had fair results, and 7.1% had poor results. There was better relief of pain in the group with arthroscopic debridement alone.     

Muscle maturation: implications for gene therapy

Skeletal muscle is a promising target tissue for gene therapy, for both muscle and non-muscle disorders. A variety of methods have been studied to transfer genes into skeletal muscle, including retroviral, adenoviral and herpes simplex viral vectors. However, various factors impede muscle-based viral gene therapy. Here, we discuss why some viral vectors cannot efficiently transduce mature muscle fibers, and describe some new approaches to overcome this barrier.     

Predictors of adherence to a structured exercise program for older women.

This study examined whether psychological, physiological, and health and lifestyle measures were associated with adherence to a structured exercise program for older women. Women aged 60 to 85 years (N?=?102), randomly recruited from the community, were assessed on these measures before and after a 12-month exercise trial. Sixty-nine women completed the trial, and 54 continued participation after the trial for at least 6 months. Adherence was examined at various stages during the trial. Multiple regression analysis revealed that reduced muscle strength, slow reaction time, and psychoactive drug use explained most of the variance in adherence during the trial. In contrast, muscle strength, reasoning ability, depression, and self-reported improvement in strength best predicted continued participation after the trial. The findings have implications for community-based exercise programs and research trials. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serum levels of insulin in overweight patients with osteoarthritis of the knee

OBJECTIVE: Obesity is often associated with knee osteoarthritis (OA) and with chronic hyperinsulinemia. The aim of our study was to investigate the relationship between overweight patients and OA of the knee. METHODS: Forty-eight overweight outpatients (40 women and 8 men) were recruited into the study. They were separated into 2 groups: Group 1 patients with OA of the knee and Group 2 subjects without OA of the knee. Serum insulin levels were determined in all patients. RESULTS: Insulin levels were statistically higher in patients with OA (p < 0.01) compared to subjects without OA. CONCLUSION: Our data suggest that insulin may play a role in the pathogenesis of OA of the knee in overweight patients.     

Incidence and risk factors for radiographic knee osteoarthritis in middle-aged women: the Chingford Study

In susceptible mouse strains, the wild-type Daniel's (wt-DA) strain of Theiler's murine encephalomyelitis virus induces a persistent central nervous system (CNS) infection with chronic demyelination. The virus is cleared from resistant mice with no resulting demyelination. We characterized the role of the DA L* protein in late demyelination and persistent infection. The DA genome has two alternative reading frames, encoding the virus polyprotein and L*, respectively. The mutant virus DAL*-1 fails to synthesize L* and does not persist in the CNS of wt-DA-susceptible SJL/J or B10.S mice. Since class I-restricted cytotoxicity has been shown to determine resistance to virus persistence and demyelination in this model, virus-specific cytotoxicity in the CNS of DA-resistant (B6 or B10) and -susceptible (SJL/J and B10.S) mice during the acute stage of DA and DAL*-1 infection was characterized. Following intracerebral inoculation with DAL*-1, virus-specific Db- and Kb-restricted CTLs were demonstrated in the CNS of resistant B10 mice, whereas only Db-restricted CTL were found in wt-DA-inoculated mice. CTLs specific to wt-DA or DAL*-1 recognized class I-presented peptides from either of the viruses. Of particular interest, Ks-restricted virus-specific cytotoxicity-restricted CTLs were identified in the CNS of susceptible SJL/J (H-2s) and B10.S (H-2s) mice inoculated with DAL*-1. In contrast, no virus-specific CTLs were identified in the CNS of SJL/J and B10.S mice inoculated with wt-DA. We propose that L* inhibits the generation of H-2K-restricted virus-specific cytotoxicity in the CNS, permitting a persistent infection in susceptible strains, with subsequent inflammatory demyelination in the CNS similar to that in human multiple sclerosis.