Search results for "KNEE"
showing 10 items of 527 documents
Non-invasive determination of cartilage thickness throughout joint surfaces using magnetic resonance imaging.
1997
Abstract Data on articular cartilage thickness in the living are important for the design of computer models, aimed at preoperatively assessing the effect of surgical procedures on joint contact and load transmission, and for the calculation of cartilage material properties from its deformational behavior as determined during arthroscopy. A non-invasive method for measuring cartilage thickness in living subjects is, however, not available. A technique based on magnetic resonance imaging has therefore been tested for assessing articular cartilage thickness throughout joint surfaces. The accuracy is determined by comparing cartilage thickness maps obtained from three patellar specimens with a…
A multi-joint lower-limb tracking-trajectory test for the assessment of motor coordination.
2005
This study aimed to determine whether a lower-limb trajectory-tracking task performed on a leg press machine, that is commonly adopted in both rehabilitation and resistance training settings, could yield reliable assessment of motor coordination in able-bodied individuals. Twenty-two female subjects allocated to two experimental groups were tested and retested after 48-72 h. Group A was fully familiarized with the experimental procedures before each test while group B received only verbal instructions. The unilateral coordination test consisted of target tracking during a simulated half squat including eccentric and concentric actions. In both groups, tracking error showed significant test-…
Caffeine Increases Strength and Power Performance in Resistance-trained Females During Early Follicular Phase
2020
The effects of 4 mg·kg−1caffeine ingestion on strength and power were investigated for the first time, in resistance-trained females during the early follicular phase utilizing a randomized, double-blind, placebo-controlled, crossover design. Fifteen females (29.8 ± 4.0 years, 63.8 ± 5.5 kg [mean ± SD]) ingested caffeine or placebo 60 minutes before completing a test battery separated by 72 hours. One-repetition maximum (1RM), repetitions to failure (RTF) at 60% of 1RM, was assessed in the squat and bench press. Maximal voluntary contraction torque (MVC) and rate of force development (RFD) were measured during isometric knee extensions, while utilizing interpolated twitch technique to measu…
Functional evaluation of patients with anterior cruciate ligament injury. A transversal analytical study.
2018
Abstract Objective To evaluate, by means of biomechanical analysis, functional alterations of gait and balance of patients with anterior cruciate ligament (ACL) injury. Material and methods Transversal analytical study on 64 people, 27 health subjects and 37 patients with ACL injury. Biomechanical analysis of gait in all individuals was performed by means of four tests: (1) kinematic test, to characterize gait pattern; (2) kinetic test, to characterize forces against the floor, duration of treads, symmetry of both legs, and the reproducibility of the gait; (3) pivot-shift test, to analyze the rotational stability of the knee on the sagittal axis; and (4) equilibrium test. Results Alteration…
The value of MRI in the evaluation of the ACL deficient knee and in the post-operative evaluation after ACL reconstruction
1993
To evaluate the usefulness of magnetic resonance imaging (MRI) in the exploration of the anterior cruciate ligament (ACL) deficient-knee, a total of twenty-five patients with chronic instability of the knee joint and who underwent both MRI and arthroscopy were studied prospectively. Twenty-three of these patients underwent an intra-articular reconstruction of the ACL with bone-patellar tendon-bone autografts. For the ACL lesions MRI had a sensitivity of 95.8%, a specificity of 100% and a diagnostic accuracy of 97.7%. Associated bowing of the PCL was seen in 20 cases of the study group. For the associated meniscal lesions MRI had a sensitivity of 77.7%, a specificity of 94.7% and a diagnosti…
Kinematic parameters after tibial nonunion treatment using the Ilizarov method
2021
Abstract Background Analysis of the outcomes of Ilizarov treatment of tibial nonunion shows functional deficits in the lower limbs of some patients. Biomechanical gait parameters are an important measure for assessing musculoskeletal disorder treatments that aim to restore normal gait. The purpose of our study was to compare the kinematic parameters in patients with tibial nonunion treated using the Ilizarov method and those in a control group of healthy volunteers. Methods The study population consisted of 23 patients (age 54.9 ± 16.4 years) who were treated for tibial nonunion using the Ilizarov method, as well as 22 healthy adult controls (age 52.7 ± 10.6 years). Kinematic parameters wer…
Symmetry function in gait pattern analysis in patients after unilateral transfemoral amputation using a mechanical or microprocessor prosthetic knee
2021
AbstractBackgroundAbove-knee amputations (AKAs) contribute to gait asymmetry. The level of asymmetry is affected by the type of knee prosthetic module. There is limited evidence suggesting that more technically advanced solutions (microprocessor modules; MicPK) are superior to less advanced ones (mechanical modules; MechPK). The study aimed to evaluate the variable range of hip and pelvic joint movements during gait and look for differentiating areas with an increased level of asymmetry of the gait cycle in individuals who underwent an AKA and are equipped with MicPK or MechPK.MethodsTwenty-eight individuals participated in the study; 14 were assigned to a study group of individuals who und…
Neuromuscular performance in voluntary bilateral and unilateral contraction and during electrical stimulation in men at different ages.
1995
A group of 33 men divided into three different age groups, M30 years (n = 11), M50 years (n = 12) and M70 years (n = 10) volunteered as subjects for examination of their maximal voluntary isometric bilateral and unilateral forces and force-time curves of the knee extensor muscle group as well as electromyogram activity of the vastus lateralis, vastus medialis and rectus femoris muscles of the right and/or left leg contractions. Electrical stimulation (ES) of 50 Hz was also given by two surface tin electrodes for each subject and each leg separately with the maximal tolerable intensity for recording the isometric force evoked. The maximal force produced by the voluntary isometric unilateral …
Basal concentrations and acute responses of serum hormones andstrength development during heavy resistance training in middle-aged andelderly men and…
2000
Effects of 6 months of heavy resistance training combined with explosive exercises on both basal concentrations and acute responses of total and free testosterone, growth hormone (GH), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), cortisol and sex hormone-binding globulin (SHBG), as well as voluntary neural activation and maximal strength of knee extensors were examined in 10 middle-aged men (M40; 42 +/- 2 years), 11 middle-aged women (W40; 39 +/- 3 years), 11 elderly men (M70; 72 +/- 3 years), and in 10 elderly women (W70; 67 +/- 3 years). The maximal integrated electromyographic (iEMG) and 1 repetition maximum (RM) knee-extension values remained unaltered in all g…
Physical activity at age of 20-64 years and mobility and muscle strength in old age: a community-based study.
2012
Background. Physical activity in midlife has been related to lower mortality and better health in old age. The present study evaluated whether physical activity at age of 20–64 years was associated with mobility and muscle strength in old age. Methods. A random sample of 1,000 persons was extracted from all the ≥75-year-old people living in Kuopio, Finland, and 679 community-dwelling participants were included in the present analyses. Data on health status, ability to walk outside or 400 m, and physical activity level were obtained through structured interviews. Participants’ walking speed, grip strength, and knee extension strength were measured by physiotherapists. Relationship between ph…