579 - The Impact of an Under Desk Seated Elliptical Trainer on Pain and Functional Outcomes in Individuals with Knee Osteoarthritis: A Randomized Controlled Trial

Objectives: Determine the impact of an under desk seated compact elliptical machine in conjunction with a standard physical therapy regimen on function and pain in individuals with knee osteoarthritis (OA).

Design: Eight-week randomized controlled trial in individuals with knee OA. Participants were randomized into the 1) Exercise only or 2) Exercise+seated elliptical (SE) group. All participants received a knee OA exercise program to complete three times a week. The Exercise+SE group also used a seated elliptical device for 30 minutes a day, five days a week. Study endpoints were measured at pre-intervention (week 0), interim (week 4) , and post-intervention visits (week 8). The study end-points were the KOOS subscales and physical function tests (6-minute and 10-meter walk tests, 5-times sit to stand, ascending/descending stair time).

Results: 26 participants were recruited (n=13 Exercise only, n=13 Exercise+SE). Both groups increased distance walked during 6-minute test from the pre-intervention to the interim visit (Exercise only p=0.02, Exercise+SE p=0.01) and decreased the time it took to ascend and descend stairs post-intervention. (p< 0.001). The Exercise+SE group decreased the time to complete a fast (p=0.05) and comfortable (p=0.03) 10-meter walk from the pre to interim visit (p=0.05) and comfortable 10-meter walk from pre- to post-intervention (p=0.01). The Exercise only group actually increased the time to complete the fast 10-meter walk test (i.e. performed worse, p< 0.01) and had a reduction in their KOOS Activities of Daily Living subscore (p=0.03) from the pre- to post-intervention visit.

Conclusions: The eight-week long exercise program improved many physical outcomes in individuals with knee OA, but individuals who used a seated elliptical trainer to augment their exercise program further improved walking speed and walking endurance compared to standard exercise. This study suggests the potential benefits of devices that provide additional convenience in exercise participation in individuals with knee OA.



Scientific Paper Best Paper Award Abstract: Research objectives

Exercise is considered the most effective, non-pharmacological treatment for reducing pain and improving function in patients with knee osteoarthritis (OA). Despite this knowledge there remain barriers with implementing increased physical activity in the daily lives of working adults often due to time constraints. An under-desk seated elliptical trainer is an aerobic exercise device that could mitigate some physical and lifestyle barriers to exercise due to the device’s low impact on the knee joints and overall convenience. The primary objective of this study is to determine the impact of an under desk seated compact elliptical machine in conjunction with a standard physical therapy regimen on function and pain in individuals with knee osteoarthritis (OA).



Design

This study is an eight-week randomized controlled trial in individuals with knee OA. Individuals over the age of 50 with a diagnosis of unilateral femoro-tibial knee OA, a diagnosis of clinical medial or radiographic knee OA, a pain score > 12.5 on the Knee Osteoarthritis Outcome Score (KOOS) were recruited for the study. All participants irrespective of group received a standard of care non-machine-based exercise program for knee OA to complete three times a week. Participants were randomized into one of two groups: 1) Exercise only (active control) or 2) Exercise + seated elliptical group (Exercise+SE) - In conjunction with the exercise the SE group used a seated elliptical device for 30 minutes a day, five days a week. Baseline physical testing and demographic data was collected prior to the 8-week program at the pre-intervention visit. Study endpoints were measured again at a 4-week interim visit and at the final 8-week post-intervention visit. The study end-points were the the KOOS subscales and physical function tests (6-minute and 10-meter walk tests, 5-times sit to stand, ascending/descending stair time at baseline, 4, and 8 weeks).



Results

26 participants were recruited (n=13 Exercise only, n=13 Exercise+SE). At baseline there were no statistical differences between groups in demographics or study endpoints.



Physical testing: Both groups significantly increased the distance walked during the 6-minute walk test from the pre-intervention to the interim visit (Exercise only 24.54 +/- 38.97; p=0.02 and Exercise+SE 19.53 +/- 26.43; p=0.01). The Exercise+SE group further decreased the time to complete a 10-meter walk at a fast speed from the pre to interim visit (-0.7 +/- 4.45; p=0.05). Of note, the Exercise only group actually significantly increased (performed worse) in the time it took to complete the fast 10-meter walk test from the pre to post intervention visit (0.54 +/- 1.8 m/s; p< 0.01). The Exercise+SE group additionally also significantly decreased the time to complete the 10-meter walk test comfortably from the pre to post-intervention visit (-0.76 +/- 5.71; p=0.01) and the interim to post-intervention visit (-0.32 +/- 5.34; p=0.03). Both groups significantly decreased the time it took to ascend and descend stairs post-intervention (p< 0.001 for both groups).

KOOS subscores: At 8 weeks, the Exercise only group had a reduction in their KOOS Activities of Daily Living (ADL) sub-score from the pre- to post-intervention visit (-0.62 +/- 28; p=0.03) suggesting a decreased ability to complete ADLs. This was not observed in the Exercise+SE group.



Conclusion

Irrespective of group the eight-week exercise program improved many functional outcomes in individuals with knee OA, but individuals who used an under desk seated elliptical trainer to augment their exercise program further improved walking speed and walking endurance. Although the pilot study findings may be attributable to the longer duration of exercise in the Exercise+SE group, the ease of use and accessibility of the device likely lead to the additional exercise engagement in this group. Future research should explore the impact of this type of device in the longer term in a larger cohort of individuals with knee OA.