Knee Osteoarthritis Rehabilitation Through Rotational Inertia

NCT07424352 | Recruiting

• 2 other identifiers: 24-1836T32TR004367
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Knee Arthritis, Osteoarthritis

Outcome Measures

Primary Outcomes (1)

• 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.

  Baseline, up to 10 weeks, up to 19 weeks

Secondary Outcomes (18)

• Stepping smoothness symmetry index

  Baseline, up to 10 weeks, up to 19 weeks

• Muscle echogenicity

  Baseline, up to 10 weeks, up to 19 weeks

• Muscle thickness

  Baseline, up to 10 weeks, up to 19 weeks

• Muscle texture analysis (gray-level co-occurrence matrix)

  Baseline, up to 10 weeks, up to 19 weeks

• Grip strength

  Baseline, up to 10 weeks, up to 19 weeks

Study Arms (2)

Initial-Exercise'

EXPERIMENTAL

The initial exercise group will participate in an 8-week eccentric overload exercise intervention using a kBox, with two sessions per week. Participants will then cease the intervention for 8 weeks to enter a detraining period.

Other: Eccentric resistance training

Delayed-Exercise

EXPERIMENTAL

The 'Delayed-Exercise' group will maintain their normal activity, without intervention, for the first 8 weeks of the study. In the second half of the study, they will begin the same 8-week kBox training completed by the 'Initial-Exercise' group.

Other: Eccentric resistance training

Interventions

Eccentric resistance training OTHER

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.

Delayed-Exercise; Initial-Exercise'

Eligibility Criteria

• Age: 40 Years - 70 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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
• No radiographic evidence of knee OA (KL Grade 0 or 1)
• No frequent knee pain
• No history of:
• Knee surgery (e.g., ACL reconstruction, meniscectomy, patellar realignment)
• Significant knee injury (e.g., ligament tears, fractures, dislocations)
• Diagnosed knee conditions (e.g., patellofemoral pain syndrome, bursitis)

You may not qualify if:

• 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
• Recent hospitalization (past 3 months)

Sponsors & Collaborators

• University of Colorado, Denver: lead
• NIH/NCATS Colorado CTSA Grant Number T32TR004367: collaborator

Study Sites (1)

University of Colorado, Denver

Aurora, Colorado, 80045, United States

RECRUITING

MeSH Terms

Conditions

Osteoarthritis

Condition Hierarchy (Ancestors)

Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases

Study Officials

• Michael Harris-Love, PT, MPT, DSc, FGSA, FAPTA

  University of Colorado, Denver

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Katie Boncella, MS

CONTACT

7207241786; katie.boncella@cuanschutz.edu

Michael Harris-Love, PT, MPT, DSc, FGSA, FAPTA

CONTACT

303-724-0687; michael.harris-love@cuanschutz.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 22, 2025
• First Posted: February 20, 2026
• Study Start: August 20, 2025
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): May 31, 2029
• Last Updated: February 20, 2026

Record last verified: 2026-02

Locations

US (1)