Non-invasive Brain Stimulation to Improve Quadriceps Muscle Function After Anterior Cruciate Ligament Reconstruction
Condition: Anterior Cruciate Ligament Reconstruction; Quadriceps Muscle Weakness; Transcranial Direct Current Stimulation
MeSH terms: Muscle Weakness
Study type: Interventional
Phase: Phase 1

Summary: 
      Quadriceps muscle dysfunction persists for years after anterior cruciate ligament
      reconstruction (ACLR) and is related to poor self-reported outcomes, altered movement
      patterns and joint loading associated with post-traumatic knee osteoarthritis (OA), and
      higher risk of reinjury. Emerging evidence indicates that central drive (pathway from the
      brain to the muscle of interest, i.e corticospinal excitability) to the quadriceps muscle is
      reduced as early as 2 weeks after surgery and can persist for years after ACLR, meaning that
      current rehabilitation strategies may not be addressing potential maladaptive changes in
      central drive. Anodal tDCS is a neurostimulation technology that increases brain excitability
      (i.e. central drive) and has the potential to address alterations in central drive and
      quadriceps muscle performance. The purpose of this study is twofold: 1) to determine the
      effects of anodal tDCS on central drive and quadriceps muscle performance in patients after
      ACLR, and 2) determine the relationship between central drive and quadriceps muscle
      performance in patients after ACLR. Central drive will be defined by two measures: 1) active
      motor thresholds, and 2) slope of a stimulus response curve. Quadriceps muscle performance
      will be defined by two measures: 1) isometric quadriceps strength, and 2) rate of torque
      development (RTD). For purpose 1 the investigators hypothesize that measures of central drive
      and quadriceps muscle performance will increase with administration of active anodal tDCS
      compared to no change with sham tDCS. For purpose 2 the investigators hypothesize that both
      measures of central drive will be associated with both measures of quadriceps performance,
      with a stronger association between central drive and RTD. Following a cross-over design
      patients 3-6 months from ACLR will receive active and sham anodal tDCS at different sessions
      separated by 7-10 days while they ride a stationary bike for 20 minutes. Bike position and
      intensity will be standardized for all patients to maximize quadriceps activity. Findings
      from this study will expand our basic science knowledge on how tDCS effects different aspects
      of corticospinal excitability and quadriceps strength, and lead to subsequent studies to
      determine the effects of multiple sessions of tDCS on corticospinal excitability and
      quadriceps muscle performance in patients recovering from ACLR.
    


Intervention name(s): Anodal transcranial direct current stimulation (tDCS) - Soterix Medical Inc, 1x1 tDCS (conventional)
Intervention type(s): Device
Intervention description(s): We will compare the effects of active versus sham tDCS on quadriceps strength and corticospinal excitability in patients recovering from ACLR.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: corticospinal excitability