ACL InjuryNCT05738200
Nordic Hamstring Exercise After ACL Reconstruction Reconstruction
A study testing Nordic Hamstring Exercise in people with ACL Injury and Muscle Weakness, run by University of Toledo at 1 site in United States.
Trial summary
Anterior cruciate ligament (ACL) injuries constitute a significant portion of major knee joint injuries sustained by young, active individuals, and significantly increase risk for long-term disability. Read more about this study
- Who is it for?
- Ages 18 to 35 years
- Conditions the study is for
- ACL Injury, Muscle Weakness, Neuromuscular Manifestations
- What is being tested?
- Nordic Hamstring Exercise
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 23 participants
- Where
- 1 siteUnited States
- Study dates
- 7 Jul 2018to 13 Jul 2022
- Phase
- Interventional
- 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 35 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Age 18-35
- History of primary, unilateral ACL reconstruction (ACLR) with hamstrings tendon autograft
Who cannot join
- Lower extremity orthopedic surgery prior to ACLR
- Post-surgical complication (e.g. infection, delayed healing)
- Multiple ligament knee injury
- Treated articular cartilage lesion
- Known history of knee osteoarthritis
- Concussion within 6 months
- History of neurological disorder
- Currently taking prescription medication that may alter neural excitability (e.g. stimulants, depressants)
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Use of Nordic Hamstring Exercise to Improve Hamstrings Function in Patients After ACL Reconstruction
Anterior cruciate ligament (ACL) injuries constitute a significant portion of major knee joint injuries sustained by young, active individuals, and significantly increase risk for long-term disability. Yet the recommended solution to restore joint stability following injury--ACL reconstruction (ACLR)--does not prevent post-traumatic knee osteoarthritis (PTOA). Post-traumatic quadriceps (dys)function is a hallmark characteristic following ACLR, reported to accelerate the onset of PTOA after ACL injury, making the recovery of muscle function a primary concern to clinicians. However, hamstrings muscle function is drastically underrepresented relative to the quadriceps in the context of recovery from ACLR, which impedes the ability to develop targeted treatment approaches. Persistent hamstrings weakness is widely reported in patients who undergo ACLR with a hamstring tendon (HT) autograft, which increases ACL strain, and may contribute to higher graft failure rates in this population. To effectively treat muscular impairments, underlying neuromuscular adaptations known to occur in response to ACLR must be targeted. Eccentric exercise is uniquely suited to enhance neuromuscular function. The Nordic hamstring exercise (NHE) is a specific form of eccentric exercise that is clinically relevant and easy to implement, but has not been explored as an intervention for hamstrings neuromuscular dysfunction in patients who undergo ACLR with HT. To establish an evidence-based treatment model, the investigators will use a single-blind, randomized controlled clinical trial to establish the feasibility and efficacy of a 4-week NHE protocol in patients who undergo ACLR with HT. Separate factorial ANOVAs will be used to assess the effects of group (NHE, control) and time (baseline, 4 weeks) on selected outcomes. Effect sizes will be calculated for within- and between-group comparisons. The investigators expect to observe improvements in hamstrings neuromuscular function following the NHE protocol, and that those improvements will be greater than the control group. Additionally, the investigators expect the protocol to be feasible in terms of intervention adherence and patient retention. This study will identify specific barriers to the implementation of NHE in patients who undergo ACLR with HT, and will provide support for the application of an easy to implement clinical intervention able to address a complex neurophysiological problem.
- Conditions
- ACL Injury, Muscle Weakness, Neuromuscular Manifestations
- Being tested
- Nordic Hamstring Exercise
- Keywords
- Eccentric exercise, Hamstrings
- Medical subject headings
- Anterior Cruciate Ligament Injuries, Muscle Weakness, Neuromuscular Manifestations
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Nordic Hamstring ExerciseOther
A 4-week (10 session), progressive, NHE protocol will be used for this study. Immediately following the completion of study visit 1, patients will be informed about the nature of the NHE protocol. Those available and willing to participate will be randomized to an intervention group (NHE, control). Patients randomized to NHE will receive formal instruction about how to correctly perform the exercise, and will be asked to perform several repetitions to familiarize themselves with the exercise and verify proper technique. At this time, patients will be dismissed from study visit 1, and return visits 2-11 will be scheduled to complete the NHE protocol. Patients will return for a final study visit (12) to record post-intervention measurements within 7 days of completing the NHE protocol. A minimum of 48 hours will be used to separate study visits. To accurately assess patients' ability to perform the NHE, all exercise will be performed on a NordBord Hamstring Testing System.
| Study group | Role | What they receive |
|---|---|---|
| Nordic Hamstring Exercise | Experimental | A 4-week (10 session), progressive, Nordic Hamstring Exercise (NHE) protocol will be used for this study. Receives: Other: Nordic Hamstring Exercise |
| Control | No intervention | Patients randomized to the control group will be instructed to avoid any changes to their normal routine (e.g., physical activity level, strength training, etc.). An investigator not involved in data collection will communicate with patients in the control group on a weekly basis to ensure they have not changed their physical activity level and do not have any questions. Patients randomized to the control group will participate in a minimum of 2 study visits at baseline and 4 weeks. These individuals will have the option to open enroll in the intervention group at the completion of their original 4-week study period. Those who choose to enroll in the intervention group at this time will return for 11 additional visits to complete the NHE protocol (visits 3-12) and final assessment (visit 13) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in peak eccentric torque
Hamstrings
Measured: Baseline, 4 weeks
Change in peak isometric torque
Hamstrings
Measured: Baseline, 4 weeks
Change in peak isokinetic torque
Hamstrings
Measured: Baseline, 4 weeks
Secondary outcomes (8)
Change in rate of torque development
Hamstrings
Measured: Baseline, 4 weeks
Change in torque coefficient of variation
Hamstrings
Measured: Baseline, 4 weeks
Change in central activation ratio
Hamstrings
Measured: Baseline, 4 weeks
Change in single leg hop
Hop for distance
Measured: Baseline, 4 weeks
Change in active motor threshold
Transcranial magnetic stimulation (TMS) derived outcome in semitendinosus
Measured: Baseline, 4 weeks
Change in cortical silent period
Transcranial magnetic stimulation (TMS) derived outcome in semitendinosus
Measured: Baseline, 4 weeks
Change in short-interval cortical inhibition
Transcranial magnetic stimulation (TMS) derived outcome in semitendinosus
Measured: Baseline, 4 weeks
Change in intracortical facilitation
Transcranial magnetic stimulation (TMS) derived outcome in semitendinosus
Measured: Baseline, 4 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Feb 2023
- Study start7 Jul 2018
- Primary completion13 Jul 2022
- Study completion13 Jul 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for ACL InjuryStudies 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 23 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Toledo
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Grant Norte, PhD, ATC, Principal investigator, The University of Toledo
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05738200
- Sponsor's protocol ID
- 202737
- Status last verified
- Feb 2023
- First submitted
- 2 Nov 2022
- Last updated
- 21 Feb 2023
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Norte GE, Glaviano NR, Sherman DA, Rush JL, Murray AM. Four-week Nordic hamstring exercise intervention for individuals with ACL reconstruction via hamstrings tendon autograft: feasibility of a pilot randomized controlled trial. Pilot Feasibility Stud. 2025 Apr 3;11(1):37. doi: 10.1186/s40814-025-01624-6.
PubMed 40181441
Study at a glance
From the registry record, last updated by the sponsor on 21 Feb 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Use of Nordic Hamstring Exercise to Improve Hamstrings Function in Patients After ACL Reconstruction
- ClinicalTrials.gov ID
- NCT05738200
- Acronym / sponsor ID
- 202737
- Conditions
- ACL Injury, Muscle Weakness, Neuromuscular Manifestations
- Keywords
- Eccentric exercise, Hamstrings
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 23 participants (actual)
- Lead sponsor
- University of ToledoUniversity, hospital or other
- Study start
- 7 Jul 2018 (actual)
- Primary completion
- 13 Jul 2022 (actual)
- Study completion
- 13 Jul 2022 (actual)
- First posted
- 21 Feb 2023 (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.
Anterior cruciate ligament (ACL) injuries constitute a significant portion of major knee joint injuries sustained by young, active individuals, and significantly increase risk for long-term disability. Yet the recommended solution to restore joint stability following injury--ACL reconstruction (ACLR)--does not prevent post-traumatic knee osteoarthritis (PTOA). Post-traumatic quadriceps (dys)function is a hallmark characteristic following ACLR, reported to accelerate the onset of PTOA after ACL injury, making the recovery of muscle function a primary concern to clinicians. However, hamstrings muscle function is drastically underrepresented relative to the quadriceps in the context of recovery from ACLR, which impedes the ability to develop targeted treatment approaches. Persistent hamstrings weakness is widely reported in patients who undergo ACLR with a hamstring tendon (HT) autograft, which increases ACL strain, and may contribute to higher graft failure rates in this population. To effectively treat muscular impairments, underlying neuromuscular adaptations known to occur in response to ACLR must be targeted. Eccentric exercise is uniquely suited to enhance neuromuscular function. The Nordic hamstring exercise (NHE) is a specific form of eccentric exercise that is clinically relevant and easy to implement, but has not been explored as an intervention for hamstrings neuromuscular dysfunction in patients who undergo ACLR with HT. To establish an evidence-based treatment model, the investigators will use a single-blind, randomized controlled clinical trial to establish the feasibility and efficacy of a 4-week NHE protocol in patients who undergo ACLR with HT. Separate factorial ANOVAs will be used to assess the effects of group (NHE, control) and time (baseline, 4 weeks) on selected outcomes. Effect sizes will be calculated for within- and between-group comparisons. The investigators expect to observe improvements in hamstrings neuromuscular function following the NHE protocol, and that those improvements will be greater than the control group. Additionally, the investigators expect the protocol to be feasible in terms of intervention adherence and patient retention. This study will identify specific barriers to the implementation of NHE in patients who undergo ACLR with HT, and will provide support for the application of an easy to implement clinical intervention able to address a complex neurophysiological problem.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Nordic Hamstring Exercise | Experimental | Other: Nordic Hamstring ExerciseA 4-week (10 session), progressive, Nordic Hamstring Exercise (NHE) protocol will be used for this study. |
| Control | No intervention | –Patients randomized to the control group will be instructed to avoid any changes to their normal routine (e.g., physical activity level, strength training, etc.). An investigator not involved in data collection will communicate with patients in the control group on a weekly basis to ensure they have not changed their physical activity level and do not have any questions. Patients randomized to the control group will participate in a minimum of 2 study visits at baseline and 4 weeks. These individuals will have the option to open enroll in the intervention group at the completion of their original 4-week study period. Those who choose to enroll in the intervention group at this time will return for 11 additional visits to complete the NHE protocol (visits 3-12) and final assessment (visit 13) |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (2 listed)
- Age 18-35
- History of primary, unilateral ACL reconstruction (ACLR) with hamstrings tendon autograft
Key exclusion criteria (8 listed)
- Lower extremity orthopedic surgery prior to ACLR
- Post-surgical complication (e.g. infection, delayed healing)
- Multiple ligament knee injury
- Treated articular cartilage lesion
- Known history of knee osteoarthritis
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 |
|---|---|---|
| Nordic Hamstring ExerciseA 4-week (10 session), progressive, NHE protocol will be used for this study. Immediately following the completion of study visit 1, patients will be informed about the nature of the NHE protocol. Those available and willing to participate will be randomized to an intervention group (NHE, control). Patients randomized to NHE will receive formal instruction about how to correctly perform the exercise, and will be asked to perform several repetitions to familiarize themselves with the exercise and verify proper technique. At this time, patients will be dismissed from study visit 1, and return visits 2-11 will be scheduled to complete the NHE protocol. Patients will return for a final study visit (12) to record post-intervention measurements within 7 days of completing the NHE protocol. A minimum of 48 hours will be used to separate study visits. To accurately assess patients' ability to perform the NHE, all exercise will be performed on a NordBord Hamstring Testing System. | Other | Nordic Hamstring Exercise |
Primary outcome
Change in peak eccentric torque
Time frame: Baseline, 4 weeks
Hamstrings
Change in peak isometric torque
Time frame: Baseline, 4 weeks
Hamstrings
Change in peak isokinetic torque
Time frame: Baseline, 4 weeks
Hamstrings
8 secondary outcomes
Change in rate of torque development
Time frame: Baseline, 4 weeks
Change in torque coefficient of variation
Time frame: Baseline, 4 weeks
Change in central activation ratio
Time frame: Baseline, 4 weeks
Change in single leg hop
Time frame: Baseline, 4 weeks
Change in active motor threshold
Time frame: Baseline, 4 weeks
Change in cortical silent period
Time frame: Baseline, 4 weeks
Change in short-interval cortical inhibition
Time frame: Baseline, 4 weeks
Change in intracortical facilitation
Time frame: Baseline, 4 weeks
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 21 Feb 2023.
- Derived from this study: PubMed 40181441Norte GE, Glaviano NR, Sherman DA, Rush JL, Murray AM. Four-week Nordic hamstring exercise intervention for individuals with ACL reconstruction via hamstrings tendon autograft: feasibility of a pilot randomized controlled trial. Pilot Feasibility Stud. 2025 Apr 3;11(1):37. doi: 10.1186/s40814-025-01624-6.
- Individual participant dataSharing planned: No
Related trials for ACL Injury
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Evaluation of the Correlation Between Bone Tunnel Projection Placement and Clinical Outcomes in Anterior Cruciate Ligament Reconstruction Surgery
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Not yet recruiting
Supporting Athletes' Return to Sports After ACL Reconstruction: A Study of a Psychological Readiness Program
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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.
Grant Norte, PhD, ATC principal investigator
The University of Toledo
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Nordic Hamstring Exercise in people with ACL Injury and Muscle Weakness, run by University of Toledo at 1 site in United States.
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 2 inclusion and 8 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 21 Feb 2023. 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 United States. 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?
Change in peak eccentric torque (time frame: Baseline, 4 weeks). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05738200, which also lists 1 linked publication.
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 21 Feb 2023.