Recruiting

Powered Unloader Orthoses

Sponsor:

University of Michigan

Code:

NCT07673328

Conditions

Lower-limb Orthoses

Osteoarthritic Knee Pain

Osteoarthritis (OA) of the Knee

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Interventions

Modular powered orthosis

Study Details

Brief summary:

The overall goal of this project is to establish a novel design and control paradigm for modular, partial-assist powered orthoses (exoskeletons) to enhance voluntary lower-limb motion and manage pain in broad patient populations. Building upon a previous study period that addressed weakness from advanced age or muscle fatigue, this current period extends the technology to novel powered unloader orthoses designed to manage knee osteoarthritis (OA) pain. The investigators hypothesize that by providing 15-30% of biological joint torque, these motorized devices can reduce muscular contributions to painful loads on the joint's surfaces during activities of daily living (ADLs). The project aims to develop a task-agnostic, neural network-based controller and establish the feasibility of reducing knee pain and muscle effort in individuals with multi-compartment knee osteoarthritis.

Conditions

Lower-limb Orthoses

Osteoarthritic Knee Pain

Osteoarthritis (OA) of the Knee

Study ID

NCT07673328

Start date

Jul 18, 2025

Status verified date

Jun, 2026

Completion date

Mar 31, 2030

Anticipated

Primary completion date

Mar 30, 2030

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Inclusion Criteria:

Inclusion criteria for able-bodied, young participants will be:

  • Aged between 18 to 65 years
  • Weigh less than 300 lbs (due to challenges in bracing heavier participants)
  • BMI < 40 (due to challenges in bracing heavier participants)

Inclusion criteria for knee osteoarthritis participants will be:

  • Aged between 30 to 85 years
  • Medical diagnosis of patellofemoral and tibiofemoral osteoarthritis
  • Patient reported pain ≥ 4 out of 10 during activities of daily life (to avoid floor effects)
  • Weigh less than 300 lbs (due to challenges in bracing heavier participants)
  • BMI < 40 (due to challenges in bracing heavier participants)
  • Ability to walk 6 minutes without assistance from a person (may use walking aid)
  • Ability to ascend/descend ramps and stairs with or without the use of handrails

Exclusion Criteria:

Exclusion criteria for able-bodied, young adult participants will be:

  • Pregnant (self-report)
  • Any significant neuromuscular or musculoskeletal disorder that would interfere with the study
  • Unable to walk for 20 minutes
  • History of any cardiovascular, vestibular, or visual diseases and/or impairments that may interfere with the study
  • Cognitive deficits that would impair their ability to give informed consent or impair their ability to follow simple instructions during the experiments. Cognitive deficits will be determined by a Mini-Mental State Examination (MMSE) score of <22.
  • Adults with a known allergy to medical grade tape

Exclusion criteria for knee osteoarthritis participants will be:

  • Pregnant (self-report)
  • Any recent lower-extremity fracture (within 6 months)
  • Significant limitation on knee joint range of motion
  • Significant neurological (e.g., stroke) or cardiovascular disorder that may affect the ability to walk
  • Advised by a physician not to walk or exercise
  • Uncontrolled hypertension or diabetes
  • Use of opioids
  • Cognitive deficits or visual impairment that would impair their ability to give informed consent or impair their ability to follow simple instructions during the experiments. Cognitive deficits will be determined by a Mini-Mental State Examination (MMSE) score of <22.
  • Adults with a known allergy to medical grade tape

Study Design

Enrollment

65 participants

Anticipated

Intervention Model

Single group

Primary purpose

Other

Interventions and Outcome Measures

Arms

experimental: Exoskeleton

Experimental: Exoskeleton

Participants in this arm of the study will perform various tasks while wearing the modular powered orthosis

Interventions

Modular powered orthosis

This study will investigate modular, lower-limb, powered orthoses that fit to user-specific weakened joints and control force/torque in a manner that enhances voluntary motion in broad patient populations. The central hypothesis is that high-torque, low-inertia motor systems controlled with energetic objectives will enable modular powered orthoses to partially assist the joints. High-torque electric motors combined with minimal transmissions can be freely rotated (i.e., backdriven) by human joints, allowing the use of an emerging torque control method called energy shaping to reduce the perceived weight/inertia of the body during any motion. By mounting these modular actuators to commercial orthoses, this technology will be easily prescribed/configured by clinicians.

Primary outcome measure

  • Muscle effort [ Time Frame: Baseline and through study completion, an average of 2 months ]
  • Joint moment load [ Time Frame: Baseline and through study completion, an average of 2 months ]
  • Pain score [ Time Frame: Baseline and through study completion, an average of 2 months ]

Central Contacts and Locations

Central contacts

Emily Klinkman

734-763-1156emilykk@umich.edu

Robert Gregg

734-763-1156rdgregg@umich.edu

Locations

Rehab Lab

Recruiting

Ann Arbor, Michigan, United States, 48109

Contacts

Emily Klinkman

734-763-1156emilykk@umich.edu

Principal Investigator:

Robert Gregg

More Information

Sponsor

University of Michigan

Last update posted

Jun 29, 2026

Last verified

Jun, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by University of Michigan on 2026-06-29.