Spontaneous ambulatory activity as a quantifiable outcome measure for osteoarthritis of the knee

What proportion of people with hip and knee osteoarthritis meet physical activity guidelines? A systematic review and meta-analysis

OBJECTIVE

To determine the proportion of people with hip and knee osteoarthritis that meet physical activity guidelines recommended for adults and older adults.

METHOD

Systematic review with meta-analysis of studies measuring physical activity of participants with hip and knee osteoarthritis using an activity monitor. Physical activity levels were calculated using the mean average [95% confidence interval (CI)] weighted according to sample size. Meta-analyses determined the proportion of people meeting physical activity guidelines and recommendations of (1) ≥150 min per week of moderate to vigorous physical activity (MVPA) in bouts of ≥10 min; (2) ≥150 min per week of MVPA in absence of bouts; (3) ≥10,000 steps per day and ≥7000 steps per day. The Grades of Research, Assessment, Development and Evaluation (GRADE) approach was used to determine the quality of the evidence.

RESULTS

For knee osteoarthritis, 21 studies involving 3266 participants averaged 50 min per week (95% CI = 46, 55) of MVPA when measured in bouts of ≥10 min, 131 min per week (95% CI = 125, 137) of MVPA, and 7753 daily steps (95% CI = 7582, 7924). Proportion meta-analyses provided high quality evidence that 13% (95% CI = 7, 20) completed ≥150 min per week of MVPA in bouts of ≥10 min, low quality evidence that 41% (95% CI = 23, 61) completed ≥150 min per week of MVPA in absence of bouts, moderate quality evidence that 19% (95% CI = 8, 33) completed ≥10,000 steps per day, and low quality evidence that 48% (95% CI = 31, 65) completed ≥7000 steps per day. For hip osteoarthritis, 11 studies involving 325 participants averaged 160 min per week (95% CI = 114, 216) of MVPA when measured in bouts of ≥10 min, 189 min per week (95% CI = 166, 212) of MVPA, and 8174 daily steps (95% CI = 7670, 8678). Proportion meta-analyses provided low quality evidence that 58% (95% CI = 18, 92) completed ≥150 min per week of MVPA in absence of bouts, low quality evidence that 30% (95% CI = 13, 50) completed ≥10,000 steps per day, and low quality evidence that 60% (95% CI = 47, 73) completed ≥7000 steps per day.

CONCLUSION

A small to moderate proportion of people with knee and hip osteoarthritis met physical activity guidelines and recommended daily steps. Future research should establish the effects of increasing physical activity in this population to meet the current physical activity guidelines.

Celecoxib improves the efficiency of the locomotor mechanism in patients with knee osteoarthritis. A randomised, placebo, double-blind and cross-over trial

OBJECTIVE

To compare the effect of celecoxib vs placebo treatment on clinical and gait variables in knee osteoarthritis (OA) patients; focusing on the efficiency of the locomotor mechanism.

STUDY DESIGN

A prospective, randomised, double-blind placebo-controlled trial.

PATIENTS

Eight adult patients with painful OA of the knee.

OUTCOME MEASURES

Clinical assessment included knee pain assessed by the visual analogue scale, range of knee motion assessed by goniometer, and locomotor function status assessed by a Knee Score Scale. Gait was assessed by means of instrumented analysis including synchronous kinematic, dynamic, electromyographic, and energetic recordings.

STATISTICAL ANALYSIS

The effect of treatment on the primary variable, the efficiency of the locomotor mechanism, and on secondary clinical and gait variables was assessed by the Hills and Armitage non-parametric approach.

RESULTS

Celecoxib treatment improved the efficiency of the locomotor mechanism significantly. Among the secondary outcome measures assessed, celecoxib treatment improved walking cadence and reduced the knee pain significantly.

CONCLUSION

This study shows that celecoxib is effective in improving locomotor function and pain in patients with knee OA.

Extraction and validation of a lower limb HAQ by comparison with objective measurement of ambulatory activity

OBJECTIVES

Both the Health Assessment Questionnaire (HAQ) and the measurement of spontaneous ambulatory activity are measures that can be used to evaluate disability in RA.

METHODS

A cross sectional survey was conducted of 105 RA patients where the HAQ was compared with ambulatory activity from the Numact monitor. Rank correlation was used to evaluate the relationships between activity and the complete and individual sections of the HAQ.

RESULTS

Correlation of activity with total HAQ produced significant results (r= -0.29 to -0.48). Correlation with individual sections showed the strongest association with "Hygiene", followed by "Activities", and "Walking". A lower limb HAQ was devised using these and the dressing and rising items.

CONCLUSIONS

HAQ and recorded activity measure different but related aspects of disability. Activity should be used if the ability to quantify the result outweighs the extra effort involved in the study.

More knee joint osteoarthritis (OA) in mice after inactivation of one allele of type II procollagen gene but less OA after lifelong voluntary wheel running exercise

OBJECTIVE

To investigate the incidence and severity of osteoarthritis (OA) and the effects of voluntary wheel running in normal mice and mice carrying either a targeted inactivation of one allele, heterozygous 'knockout', of Col2a1 gene or both alleles, homozygous 'knockout', of Col11a2 gene.

METHODS

Mice lived until 15 months of age in individual cages. Running activity was recorded around the clock. OA changes were evaluated from serial knee joint sections by light microscopy.

RESULTS

Heterozygous inactivation of Col2a1 gene coding for type II procollagen made the cartilage more susceptible to OA. At 15 months of age, OA prevalence was 60-90% in knockouts and 20-45% in normal controls (P < 0.01-0.001). Unexpectedly, a reduction of OA due to wheel running was observed in both knockout strains (P< 0.05-0.01). This effect was most evident in the femoral condyles. Incidence of OA in runners was approximately 50-85% of that in sedentary littermates. OA prevalence was higher in normal control and runner mice with high body weight. Running did not affect OA development in normal mice.

CONCLUSION

Heterozygous knockout of Col2a1 gene increased the OA prevalence in mice. Lifelong voluntary wheel running had a protective effect against OA in both knockout mice lines. The reason for this remains unknown. Reduction of OA may result from the reorganization and strengthening of the articular cartilage collagen network and/or adjacent muscles due to running, or lower body weight. Increased compliance of the articular cartilage and bones of the knockout mice may also contribute to the reduction of OA in exercised animals.

Spontaneous ambulatory activity as a quantifiable outcome measure for rheumatoid arthritis

OBJECTIVE

To validate the objective monitoring of ambulatory activity as an outcome measure for rheumatoid arthritis (RA).

METHODS

We have compared ambulatory activity to a range of currently favoured outcome measures, ranging from subjective opinions to X-ray damage, in a population of 93 RA sufferers.

RESULTS

Correlations were stronger with measures of joint damage and disability, and less strong with measures of disease activity. Sensitivity to change was good. Three different interventions were compared for the quantity of the response, and the results agree with clinical experience, with steroid injection of the knee and use of non-steroidal anti-inflammatory drugs (NSAIDs) having a similar response and the provision of surgical shoes producing a more modest increase in ambulation.

CONCLUSION

The measurement of ambulatory activity has validity for RA assessment. It provides different but related data to the currently used measures. It is objective, relevant, quantifiable and of unlimited scale. It could be used to quantify interventions aimed at increasing ambulation, in carefully constructed studies.