Anterior Cruciate Ligament ReconstructionNCT07532980
Quadriceps and Hamstring Activation Timing
An observational study of Anterior Cruciate Ligament Reconstruction and Knee Injury, run by KTO Karatay University at 1 site in Turkey (Türkiye).
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 45 years, men only
- Conditions the study is for
- Anterior Cruciate Ligament Reconstruction, Knee Injury, Neuromuscular Control
- What is being tested?
- Electromyography
- How many people
- 30 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 20 Apr 2026to 15 Jun 2026
- How long will I take part?
- 1 Day
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 45 years
- Men only
- No healthy volunteers
- Adult
Study population: The study population will consist of male individuals aged 18-45 years who have undergone anterior cruciate ligament (ACL) reconstruction using semitendinosus and gracilis tendon grafts.
Who may be able to join
- 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
Who cannot join
- 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
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Quadriceps and Hamstring Activation Timing During Functional Tasks Following ACL Reconstruction
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.
Read the 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.
- Being tested
- Electromyography
- Keywords
- ACL reconstruction, Electromyography, Muscle activation, Neuromuscular training, Rehabilitation
- Medical subject headings
- Knee Injuries
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ElectromyographyDiagnostic test
Also called Single-leg-squat protocol
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.
What is being measured
The primary outcome is the main question the study is designed to answer.
Electromyography
Muscle Activation Timing (%MVIC)
Measured: Single session (approximately 15-20 minutes per participant)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Apr 2026
- Study start20 Apr 2026
- Primary completion2 May 2026
- Study completion15 Jun 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Anterior Cruciate Ligament ReconstructionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Other
- Time perspective
- Prospective
- Enrolment
- 30 participants (actual)
- Target duration
- 1 Day
Sponsor and investigators
- Lead sponsor
- KTO Karatay University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07532980
- Sponsor's protocol ID
- 2025/029
- Status last verified
- Apr 2026
- First submitted
- 9 Apr 2026
- Last updated
- 14 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared to protect participant privacy and confidentiality.
Study at a glance
From the registry record, last updated by the sponsor on 14 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Quadriceps and Hamstring Activation Timing During Functional Tasks Following ACL Reconstruction
- ClinicalTrials.gov ID
- NCT07532980
- Acronym / sponsor ID
- 2025/029
- Keywords
- ACL reconstruction, Electromyography, Muscle activation, Neuromuscular training, Rehabilitation
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 30 participants (actual)
- Lead sponsor
- KTO Karatay UniversityUniversity, hospital or other
- Study start
- 20 Apr 2026 (actual)
- Primary completion
- 2 May 2026 (actual)
- Study completion
- 15 Jun 2026 (actual)
- First posted
- 16 Apr 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Observational model
- Other
- Time perspective
- Prospective
- Target follow-up
- 1 Day
Who may qualify
- Ages
- 18 to 45 years
- Sex
- Male only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
- Study population
- The study population will consist of male individuals aged 18-45 years who have undergone anterior cruciate ligament (ACL) reconstruction using semitendinosus and gracilis tendon grafts.
Key inclusion criteria (6 listed)
- 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;
Key exclusion criteria (6 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ElectromyographyAlso: Single-leg-squat protocolElectromyographic (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. | Diagnostic test | – |
Primary outcome
Electromyography
Time frame: Single session (approximately 15-20 minutes per participant)
Muscle Activation Timing (%MVIC)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Jul 2026.
- Individual participant dataSharing planned: No. Individual participant data will not be shared to protect participant privacy and confidentiality.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Anterior Cruciate Ligament Reconstruction and Knee Injury, run by KTO Karatay University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 14 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Electromyography (time frame: Single session (approximately 15-20 minutes per participant)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Jul 2026.