ACL Injury, ACL Tear, Anterior Cruciate Ligament Injuries, Anterior Cruciate Ligament Tear, Biomechanical Phenomena
Conditions
Keywords
vibration, quadriceps, secondary injury, ACL reconstruction, Landing biomechanics
Brief summary
Individuals who undergo anterior cruciate ligament reconstruction (ACLR) are at heightened risk of secondary anterior cruciate ligament (ACL) injury (e.g. additional injury to the ACL in either knee). One of the primary physiological consequences of ACLR is the presence of quadriceps dysfunction (i.e. reduced activation and strength) which has been linked to altered gait and landing biomechanics. Aberrant landing biomechanics have been associated with an increased risk of both primary and secondary ACL injury, thus additional research is needed to evaluate the efficacy of treatments aimed to reduce quadriceps dysfunction and restore adequate landing biomechanics in attempts to reduce secondary ACL injury. Whole-body Vibration (WBV) has demonstrated success in improving quadriceps function and gait biomechanics in individuals with ACLR, however its effectiveness on landing biomechanics is unknown. To evaluate the acute effects of WBV on landing biomechanics in those with ACLR, a non-randomized crossover-controlled trial was conducted to determine if a single bout of WBV improved landing biomechanics greater than a control condition. Participants completed two separate testing sessions (separated by at least one week) in which measures of quadriceps function and landing biomechanics were assessed before and after either a control (no WBV) or WBV intervention. Separate linear mixed-effects models of post-test values for each dependent outcome were conducted with condition (control vs WBV) and limb (ACLR vs Uninvolved) as an interaction term, and each condition pre-test values and time post-ACLR as fixed effect covariates and a random effect of subject. The investigators expect to observe a significant improvement in landing biomechanics following WBV compared to the control condition.
Interventions
Participants will stand on a WBV platform in a mini-squat position while vibration is applied during six 60-second bouts with 2 minutes of rest between each bout. WBV will be delivered at an acceleration of 2g and a frequency of 30 Hz.
Participants will stand on a WBV platform in a mini-squat position during six 60-second bouts with 2 minutes of rest between each bout. No vibration will be applied.
Sponsors
University of North Carolina, Chapel Hill
Study design
Allocation
NON_RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
No
Inclusion criteria
* Between the ages of 18-35 * History of primary, unilateral ACLR * Medically cleared for unrestricted physical activity
Exclusion criteria
* More than 5 years removed from ACLR * Currently pregnant * History of other lower extremity surgery * History of lower extremity injury in previous 6 months * History of neurological disorder * Maximal isometric quadriceps torque \> 3.0 Nm/kg in the ACLR limb
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Internal Knee Adduction Moment (KAM) | Separate values prior to and immediately following the intervention (within 5 minutes). | Peak value during landing in both single-leg and double-leg tasks averaged over 3 trials and normalized to the product of body weight and height |
| Internal Knee Extension Moment (KEM) | Separate values prior to and immediately following the intervention (within 5 minutes). | Peak value during landing in both single-leg and double-leg tasks averaged over 3 trials and normalized to a product of body weight\*height |
| Knee Flexion Angle (KFA) | Separate values prior to and immediately following the intervention (within 5 minutes). | Peak value during landing in both single-leg and double-leg tasks averaged over 3 trials |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Dynamic Postural Control | Separate values prior to and immediately following the intervention (within 5 minutes). | Time-to-stabilization during single-leg landing |
| Vertical Ground Reaction Force | Separate values prior to and immediately following the intervention (within 5 minutes). | Peak value during landing in both single-leg and double-leg tasks |
| Frontal Plane Kinematics | Separate values prior to and immediately following the intervention (within 5 minutes). | Peak value during landing in both single-leg and double-leg tasks |
Countries
United States
Contacts
PRINCIPAL_INVESTIGATORDerek Dewig
University of North Carolina, Chapel Hill
Outcome results
None listed