Search results for "knee"
showing 10 items of 527 documents
Leg and joint stiffness in human hopping
2010
The present study investigated the regulation of leg and joint stiffness in hopping at different intensity levels. Eight male subjects performed bilateral hopping at various intensity levels that were determined by peak vertical ground reaction force (GRF). In addition to the GRF, the measurements included hopping kinematics and electromyography (EMG) of selected leg muscles. While the leg and ankle joint stiffness remained invariant, the knee joint stiffness increased significantly (P<0.01) with the hopping intensity. EMG analysis revealed a significant increase in averaged EMG for all the measured muscles before and during the early phase of ground contact (P<0.05-0.001) with increasing h…
Effects of muscle activation on shear between human soleus and gastrocnemius muscles
2015
Lateral connections between muscles provide pathways for myofascial force transmission. To elucidate whether these pathways have functional roles in vivo, we examined whether activation could alter the shear between the soleus (SOL) and lateral gastrocnemius (LG) muscles. We hypothesized that selective activation of LG would decrease the stretch-induced shear between LG and SOL. Eleven volunteers underwent a series of knee joint manipulations where plantar flexion force, LG, and SOL muscle fascicle lengths and relative displacement of aponeuroses between the muscles were obtained. Data during a passive full range of motion were recorded, followed by 20° knee extension stretches in both pass…
MRI evaluation to predict tendon size for knee ligament reconstruction.
2017
Background The aim of this study is to evaluate a possible correlation between specific anthropometric parameters and sizes of knee tendons commonly used for ACL reconstruction. We hypothesized that specific clinical and radiological knee measurements could be better tendon sizes predictors than age, gender, height and weight. Materials and methods 100 consecutive patients were enrolled and 77 patients met the inclusion criteria of the study. All patients underwent a MRI of the knee with a 1.5 T super conducting MR System. For each patient, anthropometric data such as gender, height, weight, body mass index (BMI) and knee circumference were recorded. Specific MRI knee measurements were perf…
Posterior stability in posterior-stabilized vs medially congruent total knee replacement: A radiological comparison of two polyethylene designs in a …
2020
Objective:The purpose of this radiological study was to assess the posterior laxity of a single model of a total knee arthroplasty design (TKA) having a medially constrained (MC) or a Posterior-Stabilized (PS) polyethylene insert using a well-documented stress x-ray. To the authors knowledge, this is the first report evaluating MC TKA outcomes according to the “kneeling view.”Materials and Methods:Sixty patients with non-traumatic primary knee osteoarthritis undergoing TKA were first matched by age, sex, BMI and diagnosis and then divided in two groups: group A (37 knees) received a MC TKA and group B (23 knees) a PS implant made by the same manufacturer. In all cases the posterior cruciate…
Effect of neuroscience education on subjects with chronic knee pain related to osteoarthritis: a randomized controlled trial
2017
In this PhD study, the evidence for the role of central pain mechanisms in people with OA was investigated by means of a narrative and a systematic review of the existent literature. In addition, clinical criteria for recognizing central sensitization in subjects with knee OA are discussed as well as the rationale for a comprehensive integrative treatment program including pain neuroscience education and manual therapy for this population. Clinicians may find some practical problems when combining biomechanical approaches with more brain targeted approaches in a clinical setting, especially in a specific population like OA, where patients are often a bit older and tend to stick with pure bi…
Breaststroke swimmer's knee
1980
The cause of the breaststroke swimmer's knee with medial pain of the knee joint has not been clearly identified. Breaststroke swimmers with knee pain were, therefore, examined arthros copically. None showed any other disorders of their knees than medial synovitis in seven of nine swimmers. Since structural abnormalities could be ruled out, biomechanical analyses utiliz ing cinematographic techniques were used to study patients swimming in a special flume with the speed set at 90% of their best competitive performance. The results indicate that the extension and flexion and also in some cases the hip abduction and adduction movements of the whip kick were performed with high peak angular ve…
New Modalities in Knee Osteoarthritis Treatment Using Autologous Bone Marrow-Derived Mononuclear Cells
2018
Abstract The clinical effects on knee osteoarthritis (OA) symptoms and tissue structure were evaluated after bone marrow-derived mononuclear cell intraarticular injection. A group of 32 patients with 34 knee joints in stage II–III osteoarthritis were treated by intraarticular injection of mononuclear cell suspension. Clinical results were obtained by KOOS (Knee Osteoarthritis Outcome Score) and KSS (Knee Society Score) scores during a 12 months follow-up period. Radiological evaluation was performed using magnetic resonance imaging. A comparison with a control group of 28 patients treated with routinely used three hyaluronic acid intra-articular injections was made. No adverse effects were …
Use of accelerometers and gyros for hip and knee angle estimation
2013
In this paper a wearable sensor system, consisting of accelerometers and gyros, has been studied to estimate hip and knee angles. The proposed algorithm, developed in order to avoid the error accumulation due to gyroscopes drift, has been tested on angle measurement of the hip and knee of a commercial device for assisted gait. The results have shown a good accuracy of the angles estimation, also in high angle rate movement
Obesity and functional gait recovery after total hip and total knee arthroplasties : clinical and biomechanical analysis
2018
Introduction : Body Mass Index (BMI) impact on gait recovery after total hip and total knee arthroplasty (THA and TKA) remains misunderstood. Few studies have analyzed the influence of BMI on the recovery of hip and knee range of motion (ROM) during gait or walking speed after THA and TKA. Our objective was to assess this impact preoperatively and post-operatively using both 3D gait analysis and clinical assessment. Our hypothesis was that obesity (BMI> 30kg /m2) would be a negative factor in the recovery of gait parameters.Material and methods: After conducting a systematic review of the literature on functional recovery after total prostheses of the lower limb (THA and TKA) to ensure the …
Improving the cementation of the tibial component in knee arthroplasty : a study of four techniques in the cadaver.
2021
Aims The main objective of this study is to analyze the penetration of bone cement in four different full cementation techniques of the tibial tray. Methods In order to determine the best tibial tray cementation technique, we applied cement to 40 cryopreserved donor tibiae by four different techniques: 1) double-layer cementation of the tibial component and tibial bone with bone restrictor; 2) metallic cementation of the tibial component without bone restrictor; 3) bone cementation of the tibia with bone restrictor; and 4) superficial bone cementation of the tibia and metallic keel cementation of the tibial component without bone restrictor. We performed CT exams of all 40 subjects, and mea…