Differences in fatigability of vastus medialis muscle between patients with limb symmetry index of <90% and ≥90% after chronic anterior cruciate ligament reconstruction

The Knee ◽  
2021 ◽  
Vol 31 ◽  
pp. 39-45
Author(s):  
Hideyuki Sato ◽  
Yukihide Nishimura ◽  
Hiroyuki Tsuboi ◽  
Yuta Minoshima ◽  
Takeshi Sakata ◽  
...  
Keyword(s):  
Anterior Cruciate Ligament ◽  
Anterior Cruciate Ligament Reconstruction ◽  
Ligament Reconstruction ◽  
Cruciate Ligament ◽  
Vastus Medialis ◽  
Cruciate Ligament Reconstruction ◽  
Symmetry Index ◽  
Limb Symmetry Index ◽  
Vastus Medialis Muscle ◽  
Anterior Cruciate

Alterations in Quadriceps Neurologic Complexity After Anterior Cruciate Ligament Reconstruction

2020 ◽  
pp. 1-6
Author(s):  
Steven M. Davi ◽  
Colleen K. Woxholdt ◽  
Justin L. Rush ◽  
Adam S. Lepley ◽  
Lindsey K. Lepley
Keyword(s):  
Anterior Cruciate Ligament ◽  
Anterior Cruciate Ligament Reconstruction ◽  
Ligament Reconstruction ◽  
Vastus Lateralis ◽  
Cruciate Ligament ◽  
Neuromuscular Control ◽  
Electromyographic Activity ◽  
Vastus Medialis ◽  
Cruciate Ligament Reconstruction ◽  
Anterior Cruciate

Context: Traditionally, quadriceps activation failure after anterior cruciate ligament reconstruction (ACLR) is estimated using discrete isometric torque values, providing only a snapshot of neuromuscular function. Sample entropy (SampEn) is a mathematical technique that can measure neurologic complexity during the entirety of contraction, elucidating qualities of neuromuscular control not previously captured. Objective: To apply SampEn analyses to quadriceps electromyographic activity in order to more comprehensively characterize neuromuscular deficits after ACLR. Design: Cross-sectional. Setting: Laboratory. Participants: ACLR: n = 18; controls: n = 24. Interventions: All participants underwent synchronized unilateral quadriceps isometric strength, activation, and electromyography testing during a superimposed electrical stimulus. Main Outcome Measures: Group differences in strength, activation, and SampEn were evaluated with t tests. Associations between SampEn and quadriceps function were evaluated with Pearson product–moment correlations and hierarchical linear regressions. Results: Vastus medialis SampEn was significantly reduced after ACLR compared with controls (P = .032). Vastus medialis and vastus lateralis SampEn predicted significant variance in activation after ACLR (r2 = .444; P = .003). Conclusions: Loss of neurologic complexity correlates with worse activation after ACLR, particularly in the vastus medialis. Electromyographic SampEn is capable of detecting underlying patterns of variability that are associated with the loss of complexity between key neurophysiologic events after ACLR.

The Immediate Effects of Transcranial Direct Current Stimulation on Quadriceps Muscle Function in Individuals With a History of Anterior Cruciate Ligament Reconstruction: A Preliminary Investigation

2020 ◽  
Vol 29 (8) ◽  
pp. 1121-1130
Author(s):  
Justin L. Rush ◽  
Lindsey K. Lepley ◽  
Steven Davi ◽  
Adam S. Lepley
Keyword(s):  
Anterior Cruciate Ligament ◽  
Anterior Cruciate Ligament Reconstruction ◽  
Ligament Reconstruction ◽  
Cruciate Ligament ◽  
Isometric Strength ◽  
Voluntary Activation ◽  
Vastus Medialis ◽  
Cruciate Ligament Reconstruction ◽  
History Of ◽  
Anterior Cruciate

Context: Altered quadriceps activation is common following anterior cruciate ligament reconstruction (ACLR), and can persist for years after surgery. These neural deficits are due, in part, to chronic central nervous system alterations. Transcranial direct current stimulation (tDCS) is a noninvasive modality, that is, believed to immediately increase motor neuron activity by stimulating the primary motor cortex, making it a promising modality to use improve outcomes in the ACLR population. Objective: To determine if a single treatment of tDCS would result in increased quadriceps activity and decreased levels of self-reported pain and dysfunction during exercise. Design: Randomized crossover design. Setting: Controlled laboratory. Patients: Ten participants with a history of ACLR (5 males/5 females, 22.9 [4.23] y, 176.57 [12.01] cm, 80.87 [16.86] kg, 68.1 [39.37] mo since ACLR). Interventions: Active tDCS and Sham tDCS. Main Outcome Measures: Percentage of maximum electromyographic data of vastus medialis and lateralis, voluntary isometric strength, percentage of voluntary activation, and self-reported pain and symptom scores were measured. The 2 × 2 repeated-measures analysis of variance by limb were performed to explain the differences between time points (pre and post) and condition (tDCS and sham). Results: There was a significant time main effect for quadriceps percentage of maximum electromyographic of vastus medialis (F9,1 = 11.931, P = .01) and vastus lateralis (F9,1 = 9.132, P = .01), isometric strength (F9,1 = 5.343, P = .046), and subjective scores for pain (F9,1 = 15.499, P = .04) and symptoms (F9,1 = 15.499, P = .04). Quadriceps percentage of maximum electromyographic, isometric strength, and voluntary activation showed an immediate decline from pre to post regardless of tDCS condition. Subjective scores improved slightly after each condition. Conclusions: One session of active tDCS did not have an immediate effect on quadriceps activity and subjective scores of pain and symptoms. To determine if tDCS is a valid modality for this patient population, a larger scale investigation with multiple treatments of active tDCS is warranted.

scholarly journals Muscle strength capacities in elite football players after anterior cruciate ligament reconstruction

2021 ◽  
Vol 23 (2) ◽  
Author(s):  
Andreja Milutinovic ◽  
Nemanja Copic ◽  
Adam Petrovic ◽  
Milinko Dabovic ◽  
Danica Janicijevic
Keyword(s):  
Anterior Cruciate Ligament ◽  
Anterior Cruciate Ligament Reconstruction ◽  
Ligament Reconstruction ◽  
Cruciate Ligament ◽  
Peak Torque ◽  
Cruciate Ligament Reconstruction ◽  
Symmetry Index ◽  
Hamstring Muscles ◽  
Muscle Groups ◽  
Anterior Cruciate

Purpose: The aim of this study was to explore the strength capacities of the injured and non-injured leg following a unilateral anterior cruciate ligament reconstruction. Methods: Eight elite soccer players (age = 25.5 ± 3.9 years; height = 1.83 ± 0.04 m; body mass = 78.9 ± 4.5 kg) volunteered to participate in this study. Nine months after the anterior cruciate ligament reconstruction and just before initiating the full training process, the maximal peak torque of the quadriceps and hamstring muscles were measured at 60 and 180 degrees/ second using isokinetic dynamometry. Obtained peak torques were used for calculating hamstring-to-quadriceps ratio, limb symmetry index, and to estimate maximal torque capacity using a two-velocity method (i.e., linear torque-velocity relationship modeled considering peak torque obtained at 60 and 180 degrees/second). Results: No differences were found between hamstring-to- -quadriceps ratios of the injured and non-injured leg (p = 0.165), nor between limb symmetry index of the quadriceps and hamstring muscles (p = 0.985), regardless of the angular velocity applied during tests. The two-point method revealed significant differences between quadriceps and hamstring muscle groups both in the injured and non-injured leg (p < 0.001; maximal estimated torque was higher for quadriceps compared to hamstring muscles), while the differences between same muscle groups of the different legs were not significant. Conclusions: Collectively, these findings indicate that 9 months were enough for reaching a certain strength level of the injured leg that permits a safe return to play.

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