Recruiting
Early Phase 1

Observational Study

Sponsor:

University of Central Florida

Code:

NCT06999057

Conditions

Muscle Inhibition

Knee Injury Simulation

Eligibility Criteria

Sex: All

Age: 18 - 30

Healthy Volunteers: Accepted

Interventions

Joint Effusion via 60 mL Sterile Saline

Intra-articular Lidocaine

Sham injection

Study Details

Brief summary:

This study investigates how simulated knee injury-via artificial joint effusion or deafferentation-affects quadriceps motor unit behavior in healthy young adults. Participants will complete neuromuscular testing during a single 2-hour lab session. This research seeks to improve understanding of muscle inhibition and inform interventions after real-world knee trauma.

Conditions

Muscle Inhibition

Knee Injury Simulation

Study ID

NCT06999057

Start date

Aug 1, 2026

Status verified date

May, 2025

Completion date

Aug 1, 2027

Anticipated

Primary completion date

Aug 1, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 30

Healthy Volunteers: Accepted

Inclusion Criteria:

1. Age 18-30 years
2. Physically active (Tegner ≥ 5)
3. No prior lower-limb surgery or major injury

Exclusion Criteria:

1. Lower limb surgery or significant injury in past 2 years
2. Cardiopulmonary, neurological, or psychiatric disorders
3. Needle/electrical stimulation anxiety
4. Medications affecting neuromuscular or psychological function
5. Pregnancy
6. Allergic to lidocaine
7. Inability to elicit Hoffmann reflex

Study Design

Enrollment

45 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Effusion Group

60 mL sterile saline injected into knee

active comparator: Deafferentation Group

Lidocaine (single intra-articular dose)

sham comparator: Control Group

Sham procedure with fake needle

Interventions

Joint Effusion via 60 mL Sterile Saline

Injection of sterile saline into the knee joint to simulate joint swelling and induce quadriceps inhibition.

Intra-articular Lidocaine

Injection of 7 mL lidocaine into the knee joint to simulate deafferentation by temporarily blocking sensory input.

Sham injection

Simulated knee injection using a stage needle without skin penetration, used to blind participants and serve as control.

Primary outcome measure

  • Motor Unit Recruitment (amplitude relative to recruitment threshold) [ Time Frame: Baseline, 0, 30, and 60 minutes post-intervention ]
  • Motor Unit Recruitment (firing rate relative to recruitment threshold) [ Time Frame: Baseline, 0, 30, and 60 minutes post-intervention ]

Central Contacts and Locations

Central contacts

Grant Norte, Ph.D.

407-823-3188Grant.Norte@ucf.edu

Meredith Chaput, Ph.D.

Meredith.Chaput@ucf.edu

Locations

University of Central Florida

Recruiting

Orlando, Florida, United States, 32816

Contacts

Grant E. Norte

407-823-3188Grant.Norte@ucf.edu

More Information

Sponsor

University of Central Florida

Last update posted

May 1, 2026

Last verified

May, 2025

Keywords

  • Quadriceps
  • Electromyography
  • Motor Unit
  • Knee Effusion
  • Lidocaine
  • Deafferentation
  • Neuromuscular Adaptation
  • Muscle Strength

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Central Florida on 2026-05-01.