Biofeedback Training Targeting at Knee Proprioception

NCT07691528 | Completed

• 1 other identifier: 2128076
• Study Type: interventional
• Target: 14
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial was to learn if a localized knee exercise program with visual and auditory feedback improves joint awareness (proprioception) and movement quality in young adults with a history of knee injuries. It also evaluated the feasibility and safety of performing these exercises. The main questions it aimed to answer were:

1. 1.Does targeted knee training with instant audio and visual warnings improve joint position awareness and decrease movement fear?
2. 2.Is a supervised laboratory biofeedback training program more effective at improving knee function and movement consistency than an independent home training program?
3. 3.How reliable is a manual goniometer compared to an isokinetic machine when measuring joint position errors? Researchers used a crossover design where every participant completed both the home-based training program and the laboratory-based biofeedback program, separated by a two-week rest period, to compare the effectiveness of the two approaches.
4. 4.Complete two separate three-week training blocks (two sessions per week) performing squats, lunge patterns, and sidesteps.
5. 5.Attend testing sessions at the lab before and after each training block to evaluate balance, movement consistency, and joint position awareness.
6. 6.Wear smart shoe insoles and surface body sensors during testing and laboratory training to track force and joint angles.
7. 7.Keep a log of exercises and note any side effects when training independently at home.

Conditions

Knee Injury

Keywords

biofeedback training; knee proprioception

Outcome Measures

Primary Outcomes (2)

• Dispersion Index (DI) from the Action-Perception Coupling (APC) Task

  The Dispersion Index measures lower-limb joint coordination and movement consistency across the final 10 tapping repetitions of the APC task. Joint angle time-series data extracted from surface IMU sensors are used to construct a knee-hip angle-angle graph. Polar coordinate angles are calculated throughout the time series and normalized to 100% of the movement cycle. The spread of the polar coordinate angles is determined by calculating the difference between the maximum and minimum values at every 5% interval of the movement cycle. The average value of this spread is defined as the Dispersion Index (DI). A larger DI represents greater movement pattern dispersion (less consistency across repetitions), while a smaller DI indicates higher movement consistency and superior functional coordination.

  Change from Baseline (Pre-Training 1) to Post-Training 1 (Week 3), and change from Pre-Training 2 (Week 5, following a 2-week washout) to Post-Training 2 (Week 8)

• Absolute Error of Knee Joint Position Sense

  The absolute error (measured in degrees) represents the absolute difference between the target knee flexion angle (either 20° or 50°) and the angle actively replicated by the participant with their eyes closed. Lower values indicate better joint position sense and superior proprioceptive accuracy. Measurements were collected using both an isokinetic dynamometer and a manual hand-held goniometer across three trials per angle.

  Change from Baseline (Pre-Training 1) to Post-Training 1 (Week 3), and change from Pre-Training 2 (Week 5, following a 2-week washout) to Post-Training 2 (Week 8).

Secondary Outcomes (2)

• Tampa Scale of Kinesiophobia (TSK-17) Score

  Change from Baseline (Pre-Training 1) to Post-Training 1 (Week 3), and change from Pre-Training 2 (Week 5, following a 2-week washout) to Post-Training 2 (Week 8).

• Y-Balance Test Composite Score

  Change from Baseline (Pre-Training 1) to Post-Training 1 (Week 3), and change from Pre-Training 2 (Week 5, following a 2-week washout) to Post-Training 2 (Week 8).

Study Arms (2)

Laboratory Biofeedback Training

EXPERIMENTAL

Participants completed a 3-week localized knee proprioception training program performed twice weekly in a research laboratory. Surface Inertial Measurement Units (IMUs) tracked real-time knee kinematics during a standardized exercise circuit (squat holds, lateral monster walks, single-leg retro-squats, and double-leg squats). Instantaneous visual (red bar on a monitor) and auditory (beep sound) biofeedback warnings were triggered whenever a participant exceeded pre-set knee flexion thresholds of 30°, 60°, or 90°.

Behavioral: Localized Knee Proprioception Training Program

Independent Home-Based Training

ACTIVE COMPARATOR

Participants completed an identical 3-week localized knee proprioception training program performed twice weekly independently at their home or location of choice. Participants performed the exact same exercise circuit (squat holds, lateral monster walks, single-leg retro-squats, and double-leg squats) as the laboratory group but without any visual or auditory biofeedback equipment. Instead, they were instructed to target qualitative "shallow, medium, or deep" knee flexion depths and maintained a weekly paper compliance log.

Behavioral: Independent Home-Based Proprioception Training

Interventions

Localized Knee Proprioception Training Program BEHAVIORAL

A 3-week neuromuscular training program performed twice weekly. The protocol consists of a standardized lower-extremity exercise circuit including 30-second squat holds, 5-meter lateral monster walks, single-leg retro-squats, and double-leg squats performed at target knee flexion depths.

Laboratory Biofeedback Training

Independent Home-Based Proprioception Training BEHAVIORAL

A 3-week neuromuscular training program performed twice weekly independently at the participant's location of choice. Participants execute the identical lower-extremity exercise circuit (squat holds, lateral monster walks, single-leg retro-squats, and double-leg squats) but without any technological biofeedback equipment. Instead, they rely on qualitative instructions to perform the movements at shallow, medium, or deep knee flexion depths. Adherence is monitored via weekly paper compliance logs.

Independent Home-Based Training

Eligibility Criteria

• Age: 18 Years - 64 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Between the age of 18 to 64 years old.
• If the participants have a prior injury to the knee, the injury must have occurred no less than one year ago with any physical therapy concluding no less than 6 months ago.
• They are able to understand English and follow verbal instructions.

You may not qualify if:

• People who have a current neurological or musculoskeletal pathology.
• Pregnant women.
• People who had other injury/traumatic event to the lower extremity in the last year besides the knee.

Sponsors & Collaborators

• Marshall University: lead

Study Sites (1)

Marshall University

Huntington, West Virginia, 25702, United States

Location

MeSH Terms

Conditions

Knee Injuries

Condition Hierarchy (Ancestors)

Leg Injuries; Wounds and Injuries

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Model Details: This study utilized a 2x2 randomized crossover design to evaluate the effectiveness of a laboratory-based biofeedback training program versus an independent home-based training program. Following baseline testing, participants were randomly assigned to one of two sequences: starting with the laboratory biofeedback training or starting with the independent home training. Each training block lasted for 3 weeks. After the first post-training assessment, participants underwent at least 2-week washout period to eliminate any potential carryover effects before crossing over to receive the alternate training intervention.

Study Record Dates

• First Submitted: July 2, 2026
• First Posted: July 9, 2026
• Study Start: January 30, 2024
• Primary Completion: October 31, 2025
• Study Completion: October 31, 2025
• Last Updated: July 9, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)