Nordic Hamstring Exercise After ACL Reconstruction Reconstruction

Not Applicable

Completed

• Conditions: ACL Injury; Muscle Weakness; Neuromuscular Manifestations
• Interventions: Other: Nordic Hamstring Exercise

• Registration Number: NCT05738200
• Lead Sponsor: University of Toledo

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.

Detailed Description

Not available

Study Timeline

• Study Start: 2018-07-07
• Primary Completion: 2022-07-13
• Study Completion: 2022-07-13
• Study First Submitted: 2022-11-02
• Status Verified: 2023-02
• Study First Submitted QC: 2023-02-20
• Last Update Submitted: 2023-02-20
• Study First Posted: 2023-02-21
• Last Update Posted: 2023-02-21

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 23

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 & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

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

Primary Outcome Measures

Name	Time	Method
Change in peak isometric torque	Baseline, 4 weeks	Hamstrings
Change in peak isokinetic torque	Baseline, 4 weeks	Hamstrings
Change in peak eccentric torque	Baseline, 4 weeks	Hamstrings

Secondary Outcome Measures

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

Trial Locations

Locations (1)

The University of Toledo; 🇺🇸 Toledo, Ohio, United States