scholarly journals The impact of anterior cruciate ligament deficiency and reconstruction on bilateral thigh muscle activity during stair descent

2001 ◽  
Vol 57 (2) ◽  
pp. 16-21 ◽  
Author(s):  
A. St Clair Gibson ◽  
M. I. Lambert ◽  
C. L. Vaughan ◽  
M. Lowery ◽  
M. J. O'Malley ◽  
...  

Aim: To assess electromyographic (EMG) gait pattern changes during stair descent in subjects with chronic anterior cruciate ligament (ACL) deficiency, and in subjects after ACL reconstruction.Methods: Thirteen ACL deficient subjects (ACLdef), 8 ACL reconstructed subjects (ACLrec), and 10 controls (CON) participated in the study. All subjects were assessed for functional and lean thigh volume (LTV) differences in the injured and uninjured limb. All subjects then stepped off a bench with EMG electrodes on the vastus medialis, vastus lateralis and hamstrings muscles of both limbs.Results: Step down activity caused similar EMG responses in the injured and supporting limb in the ACLdef group compared to that in the control group. In contrast, in the ACLrec group, the onset of EMG activity occurred earlier during the step down activity in the vastus medialis and vastus lateralis of the supporting limb. There was significantly greater EMG activity in the vastus lateralis and hamstring muscles of the supporting limb (p < 0.05) in the ACLrec group compared to ACLdef and control groups. The changes in EMG activity did not appear to be related to differences in LTV, since greater LTV deficits were present in the ACLdef compared to the ACLrec group (p < 0.01).Conclusions: In ACL reconstructed subjects, changes in muscle recruitment patterns in the supporting limb during step down activity have been identified. This altered activity pattern was not present in the supporting limb of ACL deficient subjects

2020 ◽  
pp. 1-6
Author(s):  
Steven M. Davi ◽  
Colleen K. Woxholdt ◽  
Justin L. Rush ◽  
Adam S. Lepley ◽  
Lindsey K. Lepley

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.


2019 ◽  
Vol 26 (4) ◽  
pp. 199-203
Author(s):  
Gustavo Leporace ◽  
Gabriel Gollner Zeitoune ◽  
Thiago Vivacqua ◽  
Leonardo Metsavaht ◽  
Liszt Palmeira de Oliveira ◽  
...  

Objective: The aim of this study was to compare vastus lateralis and vastus medialis oblique (VL/VMO) muscle co-contraction (MCC) and activation ratio during gait between healthy subjects- control group (CG), and those with anterior cruciate ligament reconstruction (ACLR). Methods: Twenty-three subjects participated in this study, 14 CG and 9 ACLR. The myoelectric activities of the VL and VMO were captured to calculate the MCC. The VL/VMO ratio was obtained by dividing the normalized signals of these two muscles at each point of the curve. The MCC values and the activation ratio in the initial double limb stance, single limb stance, terminal double limb stance and swing were obtained by calculating the arithmetic mean of the intensity values ​​of the common curve in each interval. Results: MCC was significantly lower in the ACLR group during the initial double limb stance phase (p=0.001), with a high effect size (1.72). No significant differences were found for the other comparisons. Conclusions: The results of this study showed that the VL and VMO muscles co-contraction in the initial double limb stance phase of gait was different between the healthy and ACLR individuals. This finding may be related to lower patellofemoral stability during the loading response, increasing the potential risk for the development of injuries in this joint.


2021 ◽  
pp. 155633162199200
Author(s):  
Ravi Gupta ◽  
Anil Kapoor ◽  
Sourabh Khatri ◽  
Dinesh Sandal ◽  
Gladson David Masih

Background: Osteoarthritis (OA) in the anterior cruciate ligament (ACL)–deficient knee is seen in approximately 50% of affected patients. Possible causes include biochemical or biomechanical changes. Purpose: We sought to study the correlation between inflammatory cytokines and chondral damage in ACL-deficient knees. Methods: Seventy-six male patients who underwent ACL reconstruction were enrolled in a cross-sectional study. Synovial fluid was aspirated before surgery and analyzed for levels of the inflammatory cytokines tumor necrosis factor-α, interleukin-1 (IL-1), and interleukin-6 (IL-6). At the time of ACL reconstruction, the severity of chondral damage was documented as described by the Outerbridge classification. Results: Patients with grade 2 or higher chondral damage were observed to have elevated IL-6 levels when compared to patients who had no chondral damage. Interleukin-6 levels had no correlation with the duration of injury. Conclusion: Elevated levels of IL-6 in synovial fluid were associated with chondral damage in ACL-deficient knees. Further study is warranted to determine whether inflammatory cytokines contribute to the development of OA of the knee after ACL injury.


2017 ◽  
Vol 52 (11) ◽  
pp. 1079-1083
Author(s):  
Courtney E. Gray ◽  
Chris Hummel ◽  
Todd Lazenby

Background:  A collegiate women's soccer player sustained an isolated anterior cruciate ligament (ACL) tear and expressed a desire to continue her season without surgical intervention. Design:  Case report. Intervention(s):  Using the results of a randomized controlled trial and published clinical guidelines, the clinicians classified the patient as an ACL-deficient coper. The patient completed her soccer season without incident, consistent with the findings of the established clinical guidelines. However, 6 months later, she sustained a meniscal tear, which was not unexpected given that 22% of ACL-deficient copers in the randomized controlled trial incurred a meniscal tear within 24 months of ACL injury. Conclusion:  The external evidence was helpful in making informed clinical decisions regarding patient care.


2006 ◽  
Vol 88 (1) ◽  
pp. 16-17 ◽  
Author(s):  
RK Kundra ◽  
JD Moorehead ◽  
N Barton-Hanson ◽  
SC Montgomery

INTRODUCTION The Lachman test is commonly performed as part of the routine assessment of patients with suspected anterior cruciate ligament (ACL) deficiency. A major drawback is its reliance on the clinician's subjective judgement of movement. The aim of this study was to quantify Lachman movement using a magnetic tracking device thereby providing a more accurate objective measure of movement. PATIENTS AND METHODS Ten patients aged 21–51 years were assessed as having unilateral ACL deficiency with conventional clinical tests. These patients were then re-assessed using a Polhemus Fastrak™ magnetic tracking device. RESULTS The mean anterior tibial displacement was 5.6 mm (SD = 2.5) for the normal knees and 10.2 mm (SD = 4.2) for the ACL-deficient knees. This gave an 82% increase in anterior tibial displacement for the ACL deficient knees. This was shown to be highly significant with P = 0.005. CONCLUSIONS The magnetic tracking system offers an objective quantification of displacements during the Lachman test. It is convenient, non-invasive and comfortable for the patient and is, therefore, ideally suited for use as an investigative tool.


2012 ◽  
Vol 6 (1) ◽  
pp. 295-300 ◽  
Author(s):  
James Min-Leong Wong ◽  
Tanvir Khan ◽  
Chethan S Jayadev ◽  
Wasim Khan ◽  
David Johnstone

Anterior Cruciate Ligament (ACL) rupture is a common sporting injury that frequently affects young, athletic patients. Apart from the functional problems of instability, patients with ACL deficient knees also develop osteoarthritis. Although this is frequently cited as an indication for ACL reconstruction, the relationship between ACL rupture, reconstruction and the instigation and progression of articular cartilage degenerative change is controversial. The purpose of this paper is to review the published literature with regards ACL rupture and the multifactorial causes for osteoarthritis progression, and whether or not this is slowed or stopped by ACL reconstruction. There is no evidence in the published literature to support the view that ACL reconstruction prevents osteoarthritis, although it may prevent further meniscal damage. It must be recognised that this conclusion is based on the current literature which has substantial methodological limitations.


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