Nordic Hamstring Exercise After ACL Reconstruction Reconstruction

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.

Study Overview

• Status: Completed
• Conditions: Muscle Weakness; Neuromuscular Manifestations; ACL Injury
• Intervention / Treatment: Other: Nordic Hamstring Exercise

• Study Type: Interventional
• Enrollment (Actual): 23
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Ohio
    • Toledo, Ohio, United States, 43606
      • The University of Toledo

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age 18-35
• History of primary, unilateral ACL reconstruction (ACLR) with hamstrings tendon autograft

Exclusion Criteria:

• 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)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Nordic Hamstring Exercise; A 4-week (10 session), progressive, Nordic Hamstring Exercise (NHE) protocol will be used for this study.	Other: Nordic Hamstring Exercise; 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.
No Intervention: Control; 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 the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in peak eccentric torque	Hamstrings	Baseline, 4 weeks
Change in peak isometric torque	Hamstrings	Baseline, 4 weeks
Change in peak isokinetic torque	Hamstrings	Baseline, 4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in rate of torque development	Hamstrings	Baseline, 4 weeks
Change in torque coefficient of variation	Hamstrings	Baseline, 4 weeks
Change in central activation ratio	Hamstrings	Baseline, 4 weeks
Change in single leg hop	Hop for distance	Baseline, 4 weeks
Change in active motor threshold	Transcranial magnetic stimulation (TMS) derived outcome in semitendinosus	Baseline, 4 weeks
Change in cortical silent period	Transcranial magnetic stimulation (TMS) derived outcome in semitendinosus	Baseline, 4 weeks
Change in short-interval cortical inhibition	Transcranial magnetic stimulation (TMS) derived outcome in semitendinosus	Baseline, 4 weeks
Change in intracortical facilitation	Transcranial magnetic stimulation (TMS) derived outcome in semitendinosus	Baseline, 4 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in visual analog scale	Current knee pain questionnaire (range: 0 [no pain] to 10 [high pain])	Baseline, 4 weeks
Change in Tampa Scale of Kinesiophobia 11-item	Fear of pain-related movement and reinjury questionnaire (range: 11 [low fear] to 44 [high fear])	Baseline, 4 weeks
Change in ACL Return to Sport after Injury	Psychological readiness questionnaire (range: 0 [low readiness] to 100 [high readiness])	Baseline, 4 weeks
Change in International Knee Documentation Committee Subjective Knee Evaluation	Subjective knee function questionnaire (range: 0 [low function] to 100 [high function])	Baseline, 4 weeks
Change in Knee Injury and Osteoarthritis Outcome Score	Subjective knee function questionnaire (range: 0 [low function] to 100 [high function])	Baseline, 4 weeks
Veterans RAND 12-Item Health Survey	Global health questionnaire (range: 0 [low global health] to 100 [high global health])	Baseline, 4 weeks
Change in Tegner Activity Scale	Subjective activity level questionnaire (range: 0 [low activity] to 10 [high activity])	Baseline, 4 weeks
Change in International Physical Activity Questionnaire	Subjective activity level (higher values = higher activity level)	Baseline, 4 weeks
Time spent in moderate-to-vigorous physical activity	Objectively monitored physical activity	4 weeks
Global Rating of Change	Subjective perception of change in knee function following intervention (range: -7 [worse knee function] to 7 [better knee function])	4 weeks
Intrinsic Motivation Inventory	Interest/enjoyment and value/usefulness subscale questionnaires (range: 7 [no interest/enjoyment or value/usefulness] to 49 [high interest/enjoyment or value/usefulness])	4 weeks (intervention group only)
Average rating of perceived exertion	Subjective perception of effort/difficulty during exercise questionnaire (range: 6 [light effort] to 20 [high effort]), completed during each intervention session	4 weeks (intervention group only)
Average visual analog scale	Average pain or discomfort questionnaire (range: 0 [no pain/discomfort] to 10 [high pain/discomfort]), completed during each intervention session	4 weeks (intervention group only)

Collaborators and Investigators

• Sponsor: University of Toledo
• Investigators: Principal Investigator: Grant Norte, PhD, ATC, The University of Toledo

Study record dates

Study Major Dates

• Study Start (Actual): July 7, 2018
• Primary Completion (Actual): July 13, 2022
• Study Completion (Actual): July 13, 2022

Study Registration Dates

• First Submitted: November 2, 2022
• First Submitted That Met QC Criteria: February 20, 2023
• First Posted (Estimate): February 21, 2023

Study Record Updates

• Last Update Posted (Estimate): February 21, 2023
• Last Update Submitted That Met QC Criteria: February 20, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: Hamstrings; Eccentric exercise
• Additional Relevant MeSH Terms: Pathologic Processes; Nervous System Diseases; Neurologic Manifestations; Wounds and Injuries; Leg Injuries; Musculoskeletal Diseases; Muscular Diseases; Knee Injuries; Muscle Weakness; Anterior Cruciate Ligament Injuries; Neuromuscular Manifestations
• Other Study ID Numbers: 202737

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No