Nordic Hamstring Exercise After ACL Reconstruction Reconstruction

NCT05738200 | Completed

• 1 other identifier: 202737
• Study Type: interventional
• Target: 23
• Locations: 1 country
• Sites: 1

Brief 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. 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

Keywords

Eccentric exercise; Hamstrings

Outcome Measures

Primary Outcomes (3)

• 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 Outcomes (8)

• Change in rate of torque development

  Baseline, 4 weeks

• Change in torque coefficient of variation

  Baseline, 4 weeks

• Change in central activation ratio

  Baseline, 4 weeks

• Change in single leg hop

  Baseline, 4 weeks

• Change in active motor threshold

  Baseline, 4 weeks

Other Outcomes (13)

• Change in visual analog scale

  Baseline, 4 weeks

• Change in Tampa Scale of Kinesiophobia 11-item

  Baseline, 4 weeks

• Change in ACL Return to Sport after Injury

  Baseline, 4 weeks

Study Arms (2)

Nordic Hamstring Exercise

EXPERIMENTAL

A 4-week (10 session), progressive, Nordic Hamstring Exercise (NHE) protocol will be used for this study.

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)

Interventions

Nordic Hamstring Exercise OTHER

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.

Nordic Hamstring Exercise

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

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

You may not qualify if:

• 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)

Sponsors & Collaborators

• University of Toledo: lead

Study Sites (1)

The University of Toledo

Toledo, Ohio, 43606, United States

Location

Related Publications (1)

• 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.

  PMID: 40181441 DERIVED

MeSH Terms

Conditions

Anterior Cruciate Ligament Injuries; Muscle Weakness; Neuromuscular Manifestations

Condition Hierarchy (Ancestors)

Knee Injuries; Leg Injuries; Wounds and Injuries; Muscular Diseases; Musculoskeletal Diseases; Neurologic Manifestations; Nervous System Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms

Study Officials

• Grant Norte, PhD, ATC

  The University of Toledo

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 2, 2022
• First Posted: February 21, 2023
• Study Start: July 7, 2018
• Primary Completion: July 13, 2022
• Study Completion: July 13, 2022
• Last Updated: February 21, 2023

Record last verified: 2023-02

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)