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Hamstring weakness at 90° flexion of involved knee as an indicator of the function deficit in males after anterior cruciate ligament reconstruction (ACLR)

Balki Selvin, Eldemir Sefa

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 3

147--153

EN

Purpose: The aim of this study was to elucidate predictors on knee function following anterior cruciate ligament reconstruction with hamstring tendon graft or allograft and to detect the differences between it and the healthy controls. Methods: This study comprised of 46 males, aged 18–45, being within 6–60 months following unilateral anterior cruciate ligament reconstruction and 50 healthy men. Measurements included the Tampa Scale for Kinesiophobia-17, the self-reported knee function with the Knee Injury and Osteoarthritis Outcome Score, Tegner activity scale and handheld dynamometry the hamstring/quadriceps femoris muscle testing at 90° of flexion. Regression analyses were performed to predict the knee function in the anterior cruciate ligament reconstruction group. Results: The anterior cruciate ligament reconstruction group showed significantly lower Tegner activity and hamstring/quadriceps femoris strength, higher kinesiophobia and worse Knee Injury and Osteoarthritis Outcome Score (p < 0.05). Their Knee Injury and Osteoarthritis Outcome Score-Sport/Recrection, Quality of Life and –Total values were modestly associated with the satisfaction with prior rehabilitation, activity level, graft type, kinesiophobia, time since the reconstruction and hamstring strength ( p < 0.05). The hamstring strength was the only important predictor of the Knee Injury and Osteoarthritis Outcome Score-Total (p < 0.01). The involved knee handheld dynamometrymass normalize-hamstring strength at 90° of flexion predicted 20.5% of the variance in the knee function. Conclusions: Presence of a decreased handheld dynamometry-mass normalized-hamstring strength result at hyper-flexion after anterior cruciate ligament reconstruction in men may indicate self-reported knee function disorder.

2

A cadaveric study on the rate of strain-dependent behaviour of human anterior cruciate ligament

Marieswaran M., Sikidar Arnab, Rana Abhishek, Singh Dilpreet, Mansoori Nasim, Lalwani Sanjeev, Kalyanasundaram Dinesh

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 1

45--57

EN

Purpose: Failure of anterior cruciate ligament often occurs in young sports personnel hampering their career. Such ACL ruptures are quite prevalent in sports such as soccer during dynamic loading which occurs at more than one rate of loading. In this work, a structural constitutive equation has been used to predict the forces acting on ACL for different rates of loading. Methods: Ligaments with distal femur and proximal tibia were subjected to tensile loading to avoid crushing of tissue ends and slipping at higher rates of strain. Custom designed cylindrical grippers were fabricated to clamp the distal femur and proximal tibial bony sections. To estimate parameters for the model, eighteen fresh cadaveric femur-ACL-tibia complex (FATC) samples were experimented on by pure tensile loading at three orders of rates of strain viz., 0.003, 0.03, and 0.3 s–1. The experimental force-elongation data was used to obtain parameters for De-Vita and Slaughter’s equation. The model was validated with additional tensile experiments. Results: Statistical analysis demonstrated failure stress, Young’s modulus and volumetric strain energy to vary significantly as a function of rate of strain. Midsection failure was observed only in samples tested at 0.03 s–1. Femoral or tibial insertion failure were observed in all other experiments irrespective of rate of strain. Conclusion: Human FATC samples were tensile tested to failure at three rates of strain using custom-designed cylindrical grippers. A structural model was used to model the data for the ACL behaviour in the linear region of loading to predict ligament behaviour during dynamic activities in live subjects.

3

A new method of diagnosing athlete's anterior cruciate ligament health status using surface electromyography and deep convolutional neural network

Hatamzadeh Mehran, Hassannejad Reza, Sharifnezhad Ali

Biocybernetics and Biomedical Engineering

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2020

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Vol. 40, no. 1

65--76

EN

Anterior cruciate ligament (ACL) injury is one of the most common injuries in high-demand sports. Due to long-term treatment of this injury, diagnosing recovery of ACL becomes important, particularly six months postoperatively. The purpose of this research is to provide a cost-effective and intelligent method to diagnose ACL's health status. For this purpose, 11 healthy and 27 ACL-injured subjects have been selected. In the proposed method, the athlete performs a single-leg landing protocol and surface electromyographic signals (EMG) are taken from eight lower limb muscles. Then, time–frequency distributions of EMG signals in each landing are calculated as an image, using pseudo Wigner–Ville distribution (PWVD), which are the inputs of a deep convolutional neural network (DCNN). By time–frequency analysis, it has been made clear that any change in ACL's health status causes changes in the extent of energy spread in PWVD, distribution volume, frequency content, damping rate and the peak value of EMG signals. In this research, a new relationship between ACL's health status and lower limb muscles activity is introduced through monitoring of PWVD images. The result indicates that the designed expert system is able to diagnose ACL's health status with 95.8% accuracy. In this non-invasive method, PWVD images of EMG signals are chosen as the inputs of DCNN, instead of MRI images, which, in addition to their high accuracy in diagnosing, are safer and much cheaper. The presented method can play an important role in assessing the recovery process, six months postoperatively and after that.

4

Effect of preservation methods on tensile properties of human femur-ACL-tibial complex (FATC) – a cadaveric study on male subjects

Marieswaran M., Mansoori N., Digge V. K., Jhahjhria S. K., Behera C., Lalwani S., Kalyanasundaram D.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 3

31--42

EN

Deep freezing and storing in formalin are some of the common techniques of human tissue preservation. However, the preservation modes affect the biomechanical properties of the tissues. In this work, the effects of the above-stated preservation techniques are compared with that of fresh cadaveric samples. Methods: FATC samples from male cadavers of age between 60 and 70 years were tested under tensile loading at a strain rate of 0.8 s–1. Fourteen FATC samples from soft embalmed cadavers were preserved for 3 weeks by two methods: (a) 10% formalin and (b) deep freezing at –20 C followed by thawing. Seven FATC samples from fresh cadavers were experimented as control samples. The results were evaluated by a two-stage statistical process of Kruskal–Wallis H test and Mann–Whitney U-test. Results: It was observed that the failure force of fresh cadavers was the highest while that of preserved samples were approximately half the value. Failure elongation of frozen samples exceeded fresh samples while formalin samples failed at lesser elongations. Higher incidence of tibial insertion point or mid-section failures were observed in fresh samples while the higher incidence of ruptures at femoral insertion point was observed in the two preservation methods. Conclusion: Tensile properties of fresh tissues vary significantly from that of formalin preserved or frozen preserved samples.

5

Torque of the shank rotating muscles in patients with knee joint injuries

Hrycyna M., Zieliński J.

Acta of Bioengineering and Biomechanics

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2011

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Vol. 13, no. 4

77-83

EN

The aim of the study was to evaluate the torque of the shank rotating muscles in patients with reconstructed anterior cruciate ligament (ACL) and rehabilitation accomplished in comparison with a control group. The study was carried out on the group of 187 males. For the purpose of the study a prototype testing device for the shank rotating muscles' torque under static conditions was used. The study was based on the measurement of maximal torque at selected angles (-30 degree, 0 degree, 45 degree) of the shank rotation as well as on the angle (30 degree, 60 degree, 90 degree) of flexion of the knee joint. The results obtained in the group with reconstructed anterior cruciate ligament (ACL) and rehabilitation accomplished were comparable to those the control group and mostly of no statistical significance. Lack of significant differences between the values of shank rotating muscles' torque achieved in an injured limb compared to an uninjured one may testify to an effective rehabilitation process. The results of the research can serve as a diagnostic tool for the rehabilitation process development.

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Peak ground reaction force and loading rate from kinematics in the ACL deficient patients

Winiarski S., Siemieński A.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

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z. 26

377-382

EN

In clinical gait analysis ground reaction force measurement is the gait parameter which can validate the state of disorder of the patient's movement. 3D kinematic gait analysis was conducted on normal and ACL-deficient subjects to test the usefulness of ground reaction force (GRF) measurement obtained from the kinematic data of the body center of gravity (COG) in clinical condition. The 3D displacement of the COG was calculated using the Clauser model and acceleration was calculated using double differential operation. Peak force and loading rate in gait was estimated from kinematics and directly from force plate measurement.