Knee Osteoarthritis Rehabilitation Through Rotational Inertia

ConditionKnee Arthritis, Osteoarthritis

Trial statusRecruiting

Trial phaseNot applicable

Trial typeInterventional

Biological sexAll

Age40-70

SponsorUniversity of Colorado, Denver

About this trial

This study is testing whether a new type of exercise program, called eccentric overload training using a flywheel device, can improve stair-climbing ability in people with knee osteoarthritis. The flywheel device provides resistance throughout the entire movement and gives extra challenge during the muscle-lengthening phase of exercise. This type of training may improve muscle structure, strength, and coordination more effectively than conventional methods.

The study's central idea is that better muscle quality and improved coordination will lead to smoother, safer stair movement and reduce the risk of falls. Advanced tools such as ultrasound imaging and motion analysis will be used to measure muscle health and movement patterns in detail.

The hypothesis is that individuals with knee osteoarthritis have poorer muscle quality and less coordinated stair-stepping compared to healthy adults, and that performing eccentric overload training will enhance muscle quality, improve movement coordination, and make stair navigation safer and more efficient.

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

Aged 40-70 years

Radiographically confirmed knee OA (Kellgren-Lawrence [KL] Grade 2 or 3)

Able to walk independently (assistive devices permitted)

Aged 40-70 years

Disqualifiers

Uncontrolled hypertension or other cardiovascular disease

A musculoskeletal condition preventing physical testing

Neurological muscle weakness (e.g., stroke, spinal cord injury)

BMI >34.9 kg/m²

Trial design

Design model

Crossover

Treatments tested in this trial

Eccentric resistance training
Other intervention
The intervention consists of an eccentric overload resistance training program using a portable flywheel exercise device (kBox). This device generates resistance through inertia, meaning that the load is created by the individual's own movement speed and the effort applied. Participants with knee osteoarthritis will train with the flywheel system for 8 weeks, completing two to three sessions each week, with each session lasting approximately 30 to 45 minutes. The program will focus on functional lower-limb exercises such as squats, step-ups, and knee extensions. These exercises are chosen because they closely mimic everyday movements like climbing and descending stairs. Participants randomized to the delayed-exercise subgroup will continue with usual activity and medical care for the first 8 weeks, serving as a comparison group. After this waiting period, the delayed group will then be offered the same flywheel training protocol.

Treatment groups

60 Participants

are divided into 2 treatment groups

Group A: Initial-Exercise'Experimental treatment 1 intervention

Group B: Delayed-ExerciseExperimental treatment 1 intervention

Trial outcomes

Primary outcomes

Stair-stepping smoothness

Stair-stepping smoothness quantifies motor coordination during the step-up-and-over test by analyzing the fluidity and consistency of limb movements while ascending and descending stairs. It is calculated using a jerk-based smoothness metric adapted from Gonzales et al., where jerk is defined as the third derivative of the position trajectory with respect to time. The smoothness index is derived by numerically differentiating the position data x(t) obtained from motion capture three times to calculate jerk, then squaring and summing these jerk values over the duration of the movement. Lower values of the smoothness index indicate smoother, more coordinated movements. Differences in this metric will be compared between knee osteoarthritis patients and age-matched healthy controls, with variance explained through linear regression models, and between exercise intervention and delayed exercise subgroups to assess changes in motor control during stair negotiation. Unitless.

Time frame