Determining the Effects of Non-invasive Brain Stimulation to Improve Quadriceps Muscle Function After ACL Reconstruction

Official title

Determining the Effects of Non-invasive Brain Stimulation to Improve Quadriceps Muscle Function After ACL Reconstruction.

Overview

After knee surgery for a torn ACL, many women struggle with weak thigh muscles for years, partly due to reduced brain signals to these muscles. Our research tests a new approach to improve recovery by using low-level brain stimulation to boost these signals. The investigators will study 42 women, aged 18-35, who had ACL surgery. They'll be split into two groups: one receiving real brain stimulation and another getting a placebo, both during thigh-strengthening exercises. Over six sessions, the investigators measure thigh muscle strength, speed, and steadiness, plus two brain signal measures, using special equipment. The investigators will also check if stronger brain signals lead to better muscle performance, especially in women. Our goal is to show that this new method strengthens thigh muscles better than standard rehab, helping women recover better after surgery. If successful, this could improve physical therapy for women recovering from ACL surgery, making daily activities and return to sport easier.

Detailed description

Quadricep muscle impairments persist for years after anterior cruciate ligament reconstruction (ACLR). Recent evidence suggests that lower neural drive, (i.e., lower corticospinal excitably (CSE)), is associated with pronounced quadriceps muscle performance deficits, which are more severe in females recovering from ACLR than in males. Current postoperative rehabilitation protocols do not target lower neural drive, which can be achieved through non-invasive brain stimulation. Thus, the long-term goal of this research is to improve the effectiveness of ACLR rehabilitation. The objective of this project is to determine if neural drive is the critical missing link in ACLR rehabilitation. To meet this objective, the investigators will administer anodal transcranial direct current stimulation (tDCS), a type of non-invasive brain stimulation known to increase CSE. The investigators will then assess whether it improves three measures of quadriceps muscle performance (in Aim 1) and two measures of CSE (in Aim 2). In Aim 3, the investigators will determine the relationship between observed changes in quadriceps muscle performance and CSE in female participants recovering from ACLR. These aims will be achieved using a randomized, triple-blinded clinical trial with 42 female individuals after ACLR between the ages of 18 and 35 years. All participants will receive six sessions of active or sham anodal tDCS while they perform isolated quadriceps exercises on an isokinetic dynamometer. The two measures of CSE (i.e. active motor threshold and the slope of transcranial magnetic stimulation (TMS) induced recruitment curves) will be determined using surface electromyography on the vastus medialis and TMS. Three measures of quadriceps performance (i.e. peak torque normalized to body weight, rate of torque development (RTD) from 0-100ms and 100-200ms, and torque steadiness) will be determined following standard isometric muscle testing on an isokinetic dynamometer with the hips flexed to 90° and the knees flexed to 60°.

Interventions

• Device active transcranial direct current stimulation (tDCS)
  20 minutes of anodal tDCS over the primary motor cortex contralateral to the participants surgical limb during a quadriceps torque matching task
• Device sham transcranial direct current stimulation (tDCS)
  Participants receive sham tDCS in which the device only delivers current during the first and last 30 seconds while participants perform a quadriceps torque matching task

Primary outcome measures

• Peak quadriceps muscle torque [Time frame: Pre and post intervention]
• Corticospinal excitability (Slope) [Time frame: Pre and post intervention]

Secondary outcome measures (2)

• Rate of Torque Development (RTD) [Time frame: Pre and post intervention]
• Corticospinal excitability (Active Motor Threshold) [Time frame: Pre and post intervention]

Eligibility criteria

Inclusion criteria

\- females 2-6 months after ACL reconstruction

Exclusion criteria

• multiple ligament reconstruction
• osteochondral procedures
• any previous lower extremity surgery
• previous ACL injury
• Metal or implants in the head or neck
• history of neurological disease
• seizures
• severe migraines
• concussion within the last 6 months

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Triple blind

Primary purpose

Treatment

Study locations

United States · 1 center

• Ryan Zarzycki — Glenside

Publications

• Leung A, Kantak S, Hammoud S, Abraham R, Zarzycki R. Sex differences in corticospinal excitability and quadriceps performance after anterior cruciate ligament reconstruction. J Orthop Res. 2024 Apr;42(4):769-776. doi: 10.1002/jor.25725. Epub 2023 Nov 27. PMID 37938095
• Zarzycki R, Leung A, Abraham R, Hammoud S, Perrone M, Kantak S. Determining the safety, feasibility, and effects of anodal transcranial direct current stimulation on corticospinal excitability and quadriceps performance after anterior cruciate ligament reconstruction: a randomized crossover design. Ann Jt. 2025 Jan 21;10:3. doi: 10.21037/aoj-24-15. eCollection 2025. PMID 39981427

Identifiers

NCT: NCT07128602 · Arcadia University · 1R15HD118518-01

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗