Electrical Stimulation and Eccentric Exercise for Anterior Cruciate Ligament (ACL) Injury
Condition: Anterior Cruciate Ligament Injury
MeSH terms: Wounds and Injuries; Anterior Cruciate Ligament Injuries
Study type: Interventional

Summary: 
      Quadriceps muscle weakness is a common consequence of ACL injury. This muscle weakness is
      considered to result from neural inhibition preventing full muscle contraction and is
      referred to as arthrogenic muscle inhibition (AMI). AMI hinders rehabilitation by preventing
      gains in strength, increasing the risk of re-injury, and potentially placing patients at risk
      for chronic degenerative joint conditions. Quadriceps weakness that occurs following ACL
      injury is also thought to be caused by muscle atrophy which is thought to manifest due to
      alterations in muscle architecture, selective fiber atrophy or even neural deficits such as
      AMI. Importantly, interventions that are designed to counter this muscle weakness are
      required in order to promote long-term knee joint health. Hence, the purpose of the current
      study is to determine the efficacy of interventions that target quadriceps weakness to
      improve quadriceps muscle function and biomechanics in patients prior to and following ACL
      reconstruction. Specifically, the efficacy of neuromuscular electrical stimulation aimed at
      improving quadriceps neural activity and eccentric exercise intended to minimize quadriceps
      muscle atrophy will be investigated. The investigators expect that patients who receive the
      electrical stimulation therapy will demonstrate improvements in quadriceps strength and
      activation. Furthermore, it is expected that patients who receive both the electrical
      stimulation and eccentric intervention will demonstrate markedly greater gains in quadriceps
      strength and activation than patients who receive only the electrical stimulation therapy or
      standard of care post-surgery. The investigators also hypothesize that the patients who
      receive the electrical stimulation therapy and/or eccentrics will display knee motion similar
      to uninjured control subjects.
    

Detailed description: 
      Neuromuscular electrical stimulation (NMES) has been shown to reduce quadriceps activation
      failure (QAF) and eccentric exercise has been shown to lessen muscle atrophy post-ACL
      reconstruction. Given thatthese are two critical components of quadriceps strength,
      intervention combining these therapies may be effective at reinstituting quadriceps function
      post-reconstruction. Therefore, the aim of this study is to evaluate the effectiveness of a
      combined NMES and eccentric exercise intervention to improve the recovery of quadriceps
      activation and strength post-reconstruction. Patients post ACL-injury will be placed into
      four treatment groups (NMES and eccentrics; eccentrics only; NMES only, and standard of care)
      Patients assigned to the NMES and eccentric and the NMES only groups will receive the NMES
      protocol 2× per week for the first 6 weeks post-reconstruction. MES and eccentric and the
      eccentrics only groups will receive the eccentric exercise protocol 2× perweek beginning 6
      weeks post-reconstruction. Quadriceps activation was assessed via the superimposed burst
      technique and quantified via the central activation ratio.Quadriceps strength was assessed
      via maximal voluntary isomeric contractions (Nm/kg). Data will be gathered on three
      occasions: pre-operative, 12-weeks-post-surgery and at return-to-play.
    

Intervention name(s): Electrical Stimulation; Eccentric Exercise
Intervention type(s): Device; Other
Intervention description(s): Electrical stimulation will be delivered 2 times per week; Eccentric Exercise will be delivered 2 times per week
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: ACL; muscle; quadriceps; strength