Contrasting roles of inertial and muscle moments at knee and ankle during paw-shake response

1985 ◽  
Vol 54 (5) ◽  
pp. 1282-1294 ◽  
Author(s):  
M. G. Hoy ◽  
R. F. Zernicke ◽  
J. L. Smith
Keyword(s):  
Steady State ◽  
Knee Joint ◽  
Ankle Joint ◽  
Muscle Activity ◽  
Angular Acceleration ◽  
Average Maximum ◽  
Muscle Moments ◽  
Knee Muscle ◽  
State Cycles ◽  
Flexion And Extension

Intralimb kinetics of the paw-shake response (PSR) were studied in four spinal, adult cats. Using rigid body equations of motion to determine the dynamic interactions between limb segments, knee and ankle joint kinetics were calculated for the steady-state cycles as defined in the preceding paper. Hindlimb motion was filmed (200 frames/s) to obtain knee and ankle kinematics. Responses of flexors and extensors at both joints were recorded synchronously with cinefilm. Ankle and knee joint kinematics were determined from 51 steady-state cycles of 16 PSRs. Average maximum displacements, velocities, and accelerations were substantially greater for the ankle than for the knee joint. Knee and ankle motions were out of phase in the first part of the cycle; knee extension occurred simultaneously with ankle flexion. In the second part of the cycle, motions at the two joints were sequential; rapid knee flexion, accompanied by negligible ankle displacement, preceded rapid ankle extension with minimal knee displacement. At the ankle joint, peak net moments tending to cause flexion and extension were similar in magnitude and determined primarily by muscle moments. Moments due to leg angular acceleration contributed significantly to an extensor peak in the net moment near the end of the cycle. Other inertial and gravitational moments were small. At the knee joint, net moments tending to cause flexion and extension were also similar, but smaller than those at the ankle. The knee muscle moments, however, were large and counteracted large inertial moments due to paw angular acceleration. Also, moments due to leg angular acceleration and knee linear acceleration were substantial and opposite in effect. Other inertial and the gravitational moments were negligible. Muscle moments slowed and reversed joint motions, and active muscle force components of muscle moments were derived from lengthening of active musculotendinous units. Segmental interactions, in which proximal segment motion augmented distal segment velocity, increased the effectiveness of PSR steady-state cycles by facilitating the generation of extremely large paw linear accelerations. Limb oscillations during PSR steady-state result from interactions between muscle synergies and motion-dependent limb dynamics. At the ankle, muscle activity functioned to control paw acceleration, whereas at the knee, muscle activity functioned to control leg and paw inertial interactions.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals No difference in knee muscle activation and kinematics during treadmill walking between adolescent girls with and without asymptomatic Generalised Joint Hypermobility

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Helene Nikolajsen ◽  
Birgit Juul-Kristensen ◽  
Peter Fjeldstad Hendriksen ◽  
Bente Rona Jensen
Keyword(s):  
Knee Joint ◽  
Muscle Activity ◽  
Muscle Activation ◽  
Joint Hypermobility ◽  
Treadmill Walking ◽  
Group Differences ◽  
Control Group ◽  
Inclusion Criteria ◽  
Beighton Score ◽  
Knee Muscle

Abstract Background Altered knee muscle activity in children with asymptomatic Generalized Joint Hypermobility (GJH) is reported during isometric contraction, static and dynamic balance tasks and jumping, but has not been studied during gait. Therefore, the aim was to investigate group differences in knee muscle activity simultaneously with knee joint kinematics during treadmill walking between children with and without GJH. Methods Girls 14–15 years of age with GJH (inclusion criteria: Beighton score ≥6 of 9 and positive hyperextension ≥10° (one/both knees)) and a matched control group without GJH (inclusion criteria: Beighton score ≤5 and no knee hyperextension ≥10° ) were recruited. In total 16 participants with GJH and 10 non-GJH participants were included in the study. Surface electromyography (sEMG) was measured from the quadriceps, hamstrings and gastrocnemius muscles of the dominant leg during treadmill walking. Maximal voluntary isometric contractions while sitting were used for normalisation of sEMG to % of Maximum Voluntary EMG (%MVE). Knee joint angles during treadmill walking were measured by electrogoniometer. Furthermore, co-contraction index (CCI) was calculated, and presented for muscle groups of hamstrings-quadriceps (HQ) and gastrocnemius-quadriceps (GQ). CCI of medial and lateral sides of the knee, including ratio of the medial and lateral CCI for HQ and GQ were calculated. Results No group differences were found in demographics, muscle activation level, nor CCI and CCI ratios. However, participants with GJH displayed significantly decreased knee joint angle, mean (153º vs. 156º; p =0.03) and minimum (105º vs. 111º; p=0.01), during treadmill walking compared with controls. Conclusion Muscle activity during gait was not different between participants with GJH and non-GJH participants. However, participants with GJH displayed minor but statistically significant increased knee flexion during gait. Since the clinical consequences of increased knee joint flexion during gait are unknown, future studies should follow a larger cohort longitudinally during overground walking for development of clinical complications in this group.

Modeling the resistance mechanism of passive knee joint flexion and extension for use in rehabilitation equipment

2021 ◽  
pp. 095441192199013
Author(s):  
Mansoor Amiri ◽  
Farhad Tabatabai Ghomsheh ◽  
Farshad Ghazalian
Keyword(s):  
Knee Joint ◽  
Sagittal Plane ◽  
Resistance Mechanism ◽  
Time Dependent ◽  
Coefficient Of Determination ◽  
Joint Movement ◽  
Elastic Coefficient ◽  
Knee Movement ◽  
Joint Flexion ◽  
Flexion And Extension

The purpose of this study was to model the resistance mechanism of Passive Knee Joint Flexion and Extension to create a similar torque mechanism in rehabilitation equipment. In order to better model the behavior of passive knee tissues, it is necessary to exactly calculate the two coefficients of elasticity of time-independent and time-dependent parts. Ten healthy male volunteers (mean height 176.4+/−4.59 cm) participated in this study. Passive knee joint flexion and extension occurred at velocities of 15, 45, and 120 (degree/s), and in five consecutive cycles and within the range of 0 to 100° of knee movement on the sagittal plane on Cybex isokinetic dynamometer. To ensure that the muscles were relaxed, the electrical activity of knee muscles was recorded. The elastic coefficient, (KS) increased with elevating the passive velocity in flexion and extension. The elastic coefficient, (KP) was observed to grow with the passive velocity increase. While, the viscous coefficient (C) diminished with passive velocity rise in extension and flexion. The heightened passive velocity of the motion resulted in increased hysteresis (at a rate of 42%). The desired of passive velocity is lower so that there is less energy lost and the viscoelastic resistance of the tissue in the movement decreases. The Coefficient of Determination, R2 between the model-responses and experimental curves in the extension was 0.96 < R2 < 0.99 and in flexion was 0.95 < R2 < 0.99. This modeling is capable of predicting the true performance of the components of passive knee movement and we can create a resistance mechanism in the rehabilitation equipment to perform knee joint movement. Quantitative measurements of two elastic coefficients of Time-independent and Time-dependent parts passive knee joint coefficients should be used for better accurate simulation the behavior of passive tissues in the knee which is not seen in other studies.

scholarly journals Rotation Distortion Syndrome of Ankle Joint and Knee in Car Drivers and Passengers

2021 ◽  
Vol 4 (1) ◽  
Keyword(s):  
Czech Republic ◽  
Knee Joint ◽  
Hallux Valgus ◽  
Ankle Joint ◽  
Joint Pain ◽  
Pain Syndrome ◽  
Valgus Deformity ◽  
Brain Dysfunction ◽  
Front Part ◽  
Minimal Brain Dysfunction

The most common feet pathologies of children are valgus and valgus planus deformities, which are congenital or connected with neurological dysfunctions (Minimal Brain Dysfunction). In adults, and mostly in women, we observe: 1. Köhler’s disease among girls wearing improper shoes. 2. Insufficiency and pain of the front part of feet connected with limited toes flexion, 3. Valgus deformity of the big toes (hallux valgus), 4. “Ankle Joint Pain Syndrome” (AJPS)-sometimes also “Knee Joint Pain Syndrome” (KJPS)-described by us only in USA, India and Czech Republic. In presented article, we describe this special type of foot insufficiency- “instability of ankle or knee, or both joints”-on left leg in drivers and right leg in passengers in countries with right-hand traffic. More frequent it concerns the foot and article focus on this problem.

scholarly journals Neuromuscular Control of the Knee during a Resisted Single-Limb Squat Exercise

2005 ◽  
Vol 33 (10) ◽  
pp. 1520-1526 ◽  
Author(s):  
Richard K. Shields ◽  
Sangeetha Madhavan ◽  
Emy Gregg ◽  
Jennifer Leitch ◽  
Ben Petersen ◽  
...  
Keyword(s):  
Body Weight ◽  
Knee Joint ◽  
Knee Flexion ◽  
Neuromuscular Control ◽  
Biceps Femoris ◽  
Medial Gastrocnemius ◽  
Isometric Contractions ◽  
Low Resistance ◽  
Squat Exercise ◽  
Flexion And Extension

Background Closed kinetic chain exercises such as single-limb squats are preferred for knee rehabilitation. A complete understanding of the neuromuscular control of the knee during the single-limb squat is essential to increase the efficiency of rehabilitation programs. Hypothesis Performing a controlled single-limb squat with resistance to knee flexion and extension will increase the coactivation of the hamstring muscle group, thus reducing the quadriceps/hamstrings ratio. Study Design Descriptive laboratory study. Methods A total of 15 healthy human subjects (7 women, 8 men) performed controlled single-limb squats in a custom mechanical device that provided resistance to both flexion and extension. Subjects performed the task at 3 levels of resistance, set as a percentage of body weight. Surface electromyographic recordings from 7 muscles (gluteus medius, rectus femoris, vastus medialis oblique, vastus lateralis, biceps femoris, semitendinosus, and medial gastrocnemius) were collected during the task. Results Biceps femoris activity during knee flexion increased from approximately 12% maximum voluntary isometric contractions during low resistance (0% body weight) to approximately 27% maximum voluntary isometric contractions during high resistance (8% body weight). Although the quadriceps had greater activity than the hamstrings at all levels of resistance, the quadriceps/hamstrings ratio declined significantly with resistance (F2,27 = 29.05; P=. 012) from 3.0 at low resistance to 2.32 at the highest resistance. Conclusions Performing controlled resisted single-limb squats may help to simultaneously strengthen the quadriceps and facilitate coactivation of the hamstrings, thus reducing anterior tibial shear forces. The coactivation may also increase the dynamic control of the knee joint. Clinical Relevance The typical single-limb squat exercise performed in the clinic does not usually control for bidirectional resistance and knee joint excursion. As seen in this study, controlled single-limb squats at increased levels of resistance help to increase the coactivation of the hamstring muscles, which is essential to optimize neuromuscular control of the knee.

Effects of the Angular Velocity on Muscle Activity during the Knee Joint Isokinetic Contraction

2012 ◽  
Vol 48 ◽  
pp. 913-923
Author(s):  
Jong Woo Ryu ◽  
Nyeon Ju Kang ◽  
Soo Hyuk Kim ◽  
Young Ho Shin ◽  
Ho Youl Kang ◽  
...  
Keyword(s):  
Angular Velocity ◽  
Knee Joint ◽  
Muscle Activity ◽  
Isokinetic Contraction

scholarly journals Temporal Evolution of “Automatic Gain-Scaling”

2009 ◽  
Vol 102 (2) ◽  
pp. 992-1003 ◽  
Author(s):  
J. Andrew Pruszynski ◽  
Isaac Kurtzer ◽  
Timothy P. Lillicrap ◽  
Stephen H. Scott
Keyword(s):  
Steady State ◽  
Muscle Activity ◽  
Temporal Evolution ◽  
Rapid Decrease ◽  
Short Latency ◽  
State Activity ◽  
Long Latency ◽  
Short Latency Response ◽  
Latency Response ◽  
Steady State Activity

The earliest neural response to a mechanical perturbation, the short-latency stretch response (R1: 20–45 ms), is known to exhibit “automatic gain-scaling” whereby its magnitude is proportional to preperturbation muscle activity. Because gain-scaling likely reflects an intrinsic property of the motoneuron pool (via the size-recruitment principle), counteracting this property poses a fundamental challenge for the nervous system, which must ultimately counter the absolute change in load regardless of the initial muscle activity (i.e., show no gain-scaling). Here we explore the temporal evolution of gain-scaling in a simple behavioral task where subjects stabilize their arm against different background loads and randomly occurring torque perturbations. We quantified gain-scaling in four elbow muscles (brachioradialis, biceps long, triceps lateral, triceps long) over the entire sequence of muscle activity following perturbation onset—the short-latency response, long-latency response (R2: 50–75 ms; R3: 75–105 ms), early voluntary corrections (120–180 ms), and steady-state activity (750–1250 ms). In agreement with previous observations, we found that the short-latency response demonstrated substantial gain-scaling with a threefold increase in background load resulting in an approximately twofold increase in muscle activity for the same perturbation. Following the short-latency response, we found a rapid decrease in gain-scaling starting in the long-latency epoch (∼75-ms postperturbation) such that no significant gain-scaling was observed for the early voluntary corrections or steady-state activity. The rapid decrease in gain-scaling supports our recent suggestion that long-latency responses and voluntary control are inherently linked as part of an evolving sensorimotor control process through similar neural circuitry.

scholarly journals Extensor hallucis longus tendon is a new distal landmark for coronal tibial component alignment in total knee arthroplasty: A study of magnetic resonance imaging

2020 ◽  
Vol 28 (1) ◽  
pp. 230949902091234
Author(s):  
Manabu Hino ◽  
Shuji Nakagawa ◽  
Yuji Arai ◽  
Hiroaki Inoue ◽  
Hiroyuki Kan ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Total Knee Arthroplasty ◽  
Magnetic Resonance ◽  
Knee Joint ◽  
Ankle Joint ◽  
Resonance Imaging ◽  
Tibial Torsion ◽  
Valgus Angle ◽  
Extensor Hallucis Longus ◽  
Total Knee

Purpose: In total knee arthroplasty (TKA), various landmarks are generally used to ensure correct osteotomy. In this study, we examined whether the tibialis anterior tendon (TAT) or the extensor hallucis longus tendon (EHLT) could be used as a landmark of the center of the ankle joint in patients with knee osteoarthrosis (OA), using magnetic resonance imaging (MRI). Methods: The subjects were 61 patients with OA in 79 knees (males: 8 with 9 knees and females: 53 with 70 knees). With the ankle joint secured in the intermediate position, MRI from the knee joint to the ankle joint was performed in the same foot position. We prepared individual lines connecting the center of the ankle joint with the TAT or EHLT to measure the angle difference (ΔA) from Akagi’s line in the knee joint. We analyzed whether the ΔA might be affected by deformity of the knee joint or foot region, and tibial torsion. Results: At the ankle joint level, the ΔA of EHLT was the smallest, with an average of 1.6 ± 3.4°. The ΔA for the femorotibial angle, hallux valgus angle, and varus–valgus angle showed no correlations with deformity of the knee joint and foot region, or tibial torsion. Conclusions: MRI findings showed that EHLT would be useful as a landmark of the ankle joint center in extramedullary tibial osteotomy in TKA for medial knee OA. It was also clarified that the landmark would not be affected by severe deformity of the knee joint, deformity of the foot region, or external torsion of the tibia.

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