Adam S Lepley1, Monica T Ly2, Dustin R Grooms3, Jeffery M Kinsella-Shaw4, Lindsey K Lepley5. 1. School of Kinesiology, University of Michigan, Ann Arbor, MI 48109, United States; Brain Imaging Research Center, University of Connecticut, Storrs, CT, United States. Electronic address: alepley@umich.edu. 2. Brain Imaging Research Center, University of Connecticut, Storrs, CT, United States; Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States. 3. Ohio Musculoskeletal and Neurological Institute & Division of Athletic Training, School of Applied Health Sciences and Wellness, College of Health Sciences and Professions, Ohio University, Athens, OH, United States. 4. Department of Kinesiology, University of Connecticut, Storrs, CT, United States. 5. School of Kinesiology, University of Michigan, Ann Arbor, MI 48109, United States.
Abstract
BACKGROUND: Underlying neural factors contribute to poor outcomes following anterior cruciate ligament reconstruction (ACLR). Neurophysiological adaptations have been identified in corticospinal tract excitability, however limited evidence exists on neurostructural changes that may influence motor recovery in ACLR patients. OBJECTIVE: To 1) quantify hemispheric differences in structural properties of the corticospinal tract in patients with a history of ACLR, and 2) assess the relationship between excitability and corticospinal tract structure. METHODS: Ten participants with ACLR (age: 22.6 ± 1.9 yrs; height: 166.3 ± 7.5 cm; mass: 65.4 ± 12.6 kg, months from surgery: 70.0 ± 23.6) volunteered for this cross-sectional study. Corticospinal tract structure (volume; fractional anisotropy [FA]; axial diffusivity [AD]; radial diffusivity [RD]; mean diffusivity [MD]) was assessed using diffusion tensor imaging, and excitability was assessed using transcranial magnetic stimulation (motor evoked potentials normalized to maximal muscle response [MEP]) for each hemisphere. Hemispheric differences were evaluated using paired samples t-tests. Correlational analyses were conducted on structural and excitability outcomes. RESULTS: The hemisphere of the ACLR injured limb (i.e. hemisphere contralateral to the ACLR injured limb) demonstrated lower volume, lower FA, higher MD, and smaller MEPs compared to the hemisphere of the non-injured limb, indicating disrupted white matter structure and a reduction in excitability of the corticospinal tract. Greater corticospinal tract excitability was associated with larger corticospinal tract volume. CONCLUSIONS: ACLR patients demonstrated asymmetry in structural properties of the corticospinal tract that may influence the recovery of motor function following surgical reconstruction. More research is warranted to establish the influence of neurostructural measures on patient outcomes and response to treatment in ACLR populations.
BACKGROUND: Underlying neural factors contribute to poor outcomes following anterior cruciate ligament reconstruction (ACLR). Neurophysiological adaptations have been identified in corticospinal tract excitability, however limited evidence exists on neurostructural changes that may influence motor recovery in ACLR patients. OBJECTIVE: To 1) quantify hemispheric differences in structural properties of the corticospinal tract in patients with a history of ACLR, and 2) assess the relationship between excitability and corticospinal tract structure. METHODS: Ten participants with ACLR (age: 22.6 ± 1.9 yrs; height: 166.3 ± 7.5 cm; mass: 65.4 ± 12.6 kg, months from surgery: 70.0 ± 23.6) volunteered for this cross-sectional study. Corticospinal tract structure (volume; fractional anisotropy [FA]; axial diffusivity [AD]; radial diffusivity [RD]; mean diffusivity [MD]) was assessed using diffusion tensor imaging, and excitability was assessed using transcranial magnetic stimulation (motor evoked potentials normalized to maximal muscle response [MEP]) for each hemisphere. Hemispheric differences were evaluated using paired samples t-tests. Correlational analyses were conducted on structural and excitability outcomes. RESULTS: The hemisphere of the ACLR injured limb (i.e. hemisphere contralateral to the ACLR injured limb) demonstrated lower volume, lower FA, higher MD, and smaller MEPs compared to the hemisphere of the non-injured limb, indicating disrupted white matter structure and a reduction in excitability of the corticospinal tract. Greater corticospinal tract excitability was associated with larger corticospinal tract volume. CONCLUSIONS: ACLR patients demonstrated asymmetry in structural properties of the corticospinal tract that may influence the recovery of motor function following surgical reconstruction. More research is warranted to establish the influence of neurostructural measures on patient outcomes and response to treatment in ACLR populations.
Authors: Manish Anand; Jed A Diekfuss; Scott Bonnette; Ian Short; Matthew Hurn; Dustin R Grooms; Gregory D Myer Journal: Int J Sports Phys Ther Date: 2020-12
Authors: Matthew D Civilette; William R Rate; Brett D Haislup; Andrew S Cohen; Lyn Camire; Blake M Bodendorfer; Heath P Gould Journal: SAGE Open Med Date: 2022-07-30
Authors: Alli Gokeler; Alberto Grassi; Roy Hoogeslag; Albert van Houten; Caroline Bolling; Matthew Buckthorpe; Grant Norte; Anne Benjaminse; Pieter Heuvelmans; Stefano Di Paolo; Igor Tak; Francesco Della Villa Journal: J Exp Orthop Date: 2022-07-30