Anterior Cruciate Ligament Reconstruction, Knee Injury, Neuromuscular Control
Conditions
Keywords
ACL reconstruction, Electromyography, Muscle activation, Neuromuscular training, Rehabilitation
Brief summary
The anterior cruciate ligament (ACL) plays a crucial role in maintaining knee stability and enabling dynamic movement. ACL injuries are common, especially among athletes, and reconstruction surgery is frequently performed to restore knee function. Despite rehabilitation, neuromuscular deficits-particularly in muscle activation timing-may persist. This study will aim to evaluate the activation timing of quadriceps and hamstring muscles during a functional task in individuals who have undergone ACL reconstruction.
Detailed description
This study will be conducted as a cross-sectional, quantitative investigation involving male participants who have undergone ACL reconstruction using semitendinosus and gracilis tendon grafts. Electromyographic (EMG) signals will be collected using the Noraxon Ultium EMG system and analyzed with Noraxon MyoResearch XP software. Muscle activation onset timing will be assessed for the vastus medialis oblique (VMO), vastus lateralis (VL), semimembranosus (SM), semitendinosus (ST), and biceps femoris (BF). Participants will perform a standardized single-leg squat task, during which EMG-based activation timing will be recorded. The findings are expected to provide insight into neuromuscular control strategies and inform rehabilitation approaches following ACL reconstruction.
Interventions
DIAGNOSTIC_TESTElectromyography
Electromyographic (EMG) data will be collected using the Noraxon Ultium EMG sensor system (Noraxon USA, Inc., Scottsdale, Arizona; sampling frequency: 4000 Hz per channel; gain: 1000 \[signal-to-noise ratio: 1 μV RMS\]; common mode rejection rate \[CMRR\]: -100 dB; input impedance: \>100 MΩ). Prior to electrode placement, any hair on the skin will be removed, and the skin will be cleansed with an alcohol swab to ensure optimal signal quality. Participants will be instructed to cross their arms over their chest and perform the squat slowly and in a controlled manner while maintaining balance. The knee flexion angle will be standardized at 60°, and this angle will be monitored and adjusted using an inclinometer integrated into the EMG system. A metronome will be used to control the squatting speed. Participants will be instructed to reach the squat position within 3 beats of the metronome, maintain the squat position for 3 beats, and return to the starting position within 3 beats.
Sponsors
KTO Karatay University
Study design
Observational model
OTHER
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
MALE
Age
18 Years to 45 Years
Healthy volunteers
No
Inclusion criteria
* participants must be males between 18 and 45 years old * must have undergone ACL repair surgery and be within 6 months to 2 years post-surgery * should have completed a standard rehabilitation program post-surgery * must provide written informed consent to participate in the study * should be in generally good health, without any other significant medical conditions that could affect the study outcomes; * must have returned to a moderate level of physical activity post-surgery
Exclusion criteria
* participants with any neurological disorders affecting lower limb function or any other musculoskeletal disorders or injuries that could affect the lower limb, apart from the ACL injury * those with cardiovascular conditions that contraindicate participation in physical activity * those with contraindications to kinesiological electromyography, such as skin conditions or allergies to electrodes * those who are unable or unwilling to comply with study procedures and follow-ups * those who have had multiple ACL surgeries on the same knee * participants involved in ongoing litigation related to their ACL injury
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Electromyography | Single session (approximately 15-20 minutes per participant) | Muscle Activation Timing (%MVIC) |
Countries
Turkey (Türkiye)
Outcome results
None listed