ACL
Conditions
Keywords
ACLR, quadriceps, neuromuscular electrical stimulation, vibration
Brief summary
The investigators are interested in determining what treatments are effective in reducing inhibition after anterior cruciate ligament (ACL) surgery and helping people increase quadriceps strength. Two interventions that are often used clinically are neuromuscular electrical stimulation (NMES) and vibration. This is a study of how effective these treatments are, whether they work the same for everyone, and if one is better than the other. 22 participants will be enrolled and on study for 2 to 3 weeks.
Detailed description
After a screening visit, participants will be randomized to 2 intervention conditions over 2, 60-minute visits at least 1 week apart where they will complete: * a 5 minute low intensity warm-up on a stationary bike * a series of patient-reported outcomes surveys * a pre-intervention quadriceps performance assessment * the intervention condition, one each visit, either: * \ 20 minutes of NMES while completing rehabilitation exercises, OR * \ 20 minutes of hamstring muscle vibration * a post-intervention quadriceps performance assessment The primary objective of the study is to characterize the acute effects of interventions designed to mitigate the influence of inhibition (NMES and hamstrings muscle vibration) on quadriceps muscle performance in people post-anterior cruciate ligament reconstruction (ACLR) who have significant potential to benefit from these interventions (e.g. less than 4 months post-surgery). * Specific Aim 1: To determine the acute effects of quadriceps NMES and hamstrings muscle vibration on quadriceps muscle performance in people 2-4 months post-ACLR * Specific Aim 2: To determine if individuals with signs of more pronounced neural inhibition (quantified via assessment of knee extensor torque steadiness) have greater responses to NMES and hamstrings muscle vibration Hypothesis 1: Quadriceps muscle strength will increase in people 2-4 months post-ACLR after 20 minutes of quadriceps NMES or hamstrings muscle vibration. The magnitude of increase in strength will be similar for both interventions. Hypothesis 2: Surgical limb knee extensor torque steadiness will be strongly positively correlated with changes in quadriceps strength after NMES or hamstrings muscle vibration. People with greater steadiness impairments will demonstrate greater acute increases in quadriceps strength.
Interventions
DEVICENMES
The thigh of the surgical leg will be cleaned with isopropyl alcohol. 2.75" x 5" NMES electrodes (Dura-Stick Plus, Chattanooga, DJO Global, Dallas, TX) will be adhered to the proximal and distal aspects of the quadriceps muscles. An FDA-approved portable neuromuscular electrical stimulator (Empi Continuum, DJO Global, Dallas, TX) will be utilized to deliver a biphasic square wave pulse (frequency 75 Hz, pulse width 300 µs) to the quadriceps of the surgical limb. Participants will control both the amplitude of current delivered (0-100 mA) and the on/off timing of the stimulation via a wired control switch. Participants will complete common post-ACLR rehabilitation exercises while NMES is delivered (total time for exercises is approximately 20 minutes).
DEVICEVibration
Participants will sit in a comfortable position on a treatment plinth with knees flexed to \~30°, hips flexed between 30-60°, and the back supported. The back of the thighs will rest on the vibration pads of a commercial vibration device (Thumper Versa Pro Massager, (Thumper Massager Inc., Markham, Ontario, CA). Participants will sit at rest for 20 minutes while the vibration device provides a 30 Hz vibration with an amplitude of \~6 mm.
Sponsors
University of Wisconsin, Madison
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
No
Inclusion criteria
* Have undergone ACLR within the previous 4 months * Are at least 2 months post-ACLR
Exclusion criteria
* A history of ACLR on both legs * Since the most recent ACLR: * secondary lower extremity surgery * leg or foot fracture * Unable to walk without an assistive device * Pain of greater than 5/10 during quadriceps strengthening exercises with the surgical limb * Cannot achieve 90 degrees of knee flexion with the surgical limb * People with contraindications to NMES * Anyone who had a previous skin reaction to NMES or attempted but could not tolerate NMES * Peripheral neuropathy or other neurological conditions
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Change in knee extensor peak torque production | measured pre-intervention and post-intervention during each of 2, 1-hour study visits, data collection complete within 3 weeks |
Secondary
| Measure | Time frame |
|---|---|
| Change in knee extensor torque steadiness | measured pre-intervention and post-intervention during each of 2, 1-hour study visits, data collection complete within 3 weeks |
Countries
United States
Contacts
CONTACTDaniel Cobian, DPT, PhD
PRINCIPAL_INVESTIGATORDaniel Cobian, DPT, PhD
University of Wisconsin, Madison
Outcome results
None listed