knee position
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2022 ◽  
Vol 12 (2) ◽  
pp. 830
Author(s):  
Pedro Harry-Leite ◽  
Manuel Paquete ◽  
José Teixeira ◽  
Miguel Santos ◽  
José Sousa ◽  
...  

This study aimed to compare the acute effect of a proprioceptive exercise session and a non-specific exercise session on knee position sense, and the static and dynamic balance of athletes. Sixty male athletes (19.4 ± 1.2 years) participated in a within-subjects repeated-measures study. Knee position sense in closed kinetic chain, and static (BESS test) and dynamic balance (Y-balance test) were measured before and after two exercise sessions, consisting of 10 min of non-specific exercise in a cycle-ergometer or proprioceptive exercise with an unstable platform. Overall, both exercise sessions significantly improved knee position sense, BESS score, and YBT composite score, and no differences were detected between proprioceptive and non-specific sessions (knee position sense, −6.9 ± 65.2% vs. −11.5 ± 75.0%, p = 0.680; BESS, −19.3 ± 47.7% vs. −29.03 ± 23.5%, p = 0.121; YBT, 2.6 ± 2.7% vs. 2.2 ± 2.2%, p = 0.305). Twenty athletes did not improve knee position sense after the exercise session (non-responders). When analyzing only the exercise responders, both sessions improved knee position sense, but the improvement was greater after the proprioceptive exercise session (56.4 ± 25.6% vs. 43.8 ± 18.9%, p = 0.023). In conclusion, a single proprioceptive, as well as non-specific, exercise session increased knee position sense and balance. The proprioceptive exercise seems to be more effective in improving joint position sense when considering only athletes who respond to the intervention.


2022 ◽  
Vol 22 (1) ◽  
Author(s):  
Chia-Ming Chang ◽  
Chon-Haw Tsai ◽  
Ming-Kuei Lu ◽  
Hsin-Chun Tseng ◽  
Grace Lu ◽  
...  

Abstract Background Whole-body vibration (WBV) training can provoke reactive muscle response and thus exert beneficial effects in various neurological patients. This study aimed to investigate the muscles activation and acceleration transmissibility of the lower extremity to try to understand the neuromuscular control in the Parkinson’s disease (PD) patients under different conditions of the WBV training, including position and frequency. Methods Sixteen PD patients and sixteen controls were enrolled. Each of them would receive two WBV training sessions with 3 and 20 Hz mechanical vibration in separated days. In each session, they were asked to stand on the WBV machine with straight and then bended knee joint positions, while the vibration stimulation was delivered or not. The electromyographic (EMG) signals and the segmental acceleration from the lower extremity were recorded and processed. The amplitude, co-contraction indexes (CCI), and normalized median frequency slope (NMFS) from the EMG signals, and the acceleration transmissibility were calculated. Results The results showed larger rectus femoris (RF) amplitudes under 3 Hz vibration than those in 20 Hz and no vibration conditions; larger tibialis anterior (TA) in 20 Hz than in no vibration; larger gastrocnemius (GAS) in 20 Hz than in 3 Hz and no vibration. These results indicated that different vibration frequencies mainly induced reactive responses in different muscles, by showing higher activation of the knee extensors in 3 Hz and of the lower leg muscles in 20 Hz condition, respectively. Comparing between groups, the PD patients reacted to the WBV stimulation by showing larger muscle activations in hamstring (HAM), TA and GAS, and smaller CCI in thigh than those in the controls. In bended knee, it demonstrated a higher RF amplitude and a steeper NMFS but smaller HAM activations than in straight knee position. The higher acceleration transmissibility was found in the control group, in the straight knee position and in the 3 Hz vibration conditions. Conclusion The PD patients demonstrated altered neuromuscular control compared with the controls in responding to the WBV stimulations, with generally higher EMG amplitude of lower extremity muscles. For designing WBV strengthening protocol in the PD population, the 3 Hz with straight or flexed knee protocol was recommended to recruit more thigh muscles; the bended knee position with 20 Hz vibration was for the shank muscles.


2021 ◽  
Author(s):  
Sarah Hood ◽  
Lukas Gabert ◽  
Tommaso Lenzi

Powered prostheses can enable individuals with above-knee amputations to ascend stairs step-over-step. To accomplish this task, available stair ascent controllers impose a pre-defined joint impedance behavior or follow a pre-programmed position trajectory. These control approaches have proved successful in the laboratory. However, they are not robust to changes in stair height or cadence, which is essential for real-world ambulation. Here we present an adaptive stair ascent controller that enables individuals with above-knee amputations to climb stairs of varying stair heights at their preferred cadence and with their preferred gait pattern. We found that modulating the prosthesis knee and ankle position as a function of the user’s thigh in swing provides toe clearance for varying stair heights. In stance, modulating the torque-angle relationship as a function of the prosthesis knee position at foot contact provides sufficient torque assistance for climbing stairs of different heights. Furthermore, the proposed controller enables individuals to climb stairs at their preferred cadence and gait pattern, such as step-by-step, step-over-step, and two-steps. The proposed adaptive stair controller may improve the robustness of powered prostheses to environmental and human variance, enabling powered prostheses to more easily move from the lab to the real-world.


Author(s):  
Fatemeh Ghasemi Dehcheshmeh ◽  
Ali Amiri ◽  
Nader Maroufi ◽  
Aliashraf Jamshidi ◽  
Shohreh Jalaei

Introduction: Knee joint injuries usually occur in a short time, so analyzing the mechanism and process of this short time can be helpful to prevent similar injuries. This study aimed to determine and compare the reaction time of knee muscles and investigate the effect of  knee position and perturbation direction on the reaction time of knee muscles in response to horizontal rotational perturbation applied to lower leg from support surface area. Materials and Methods: A total of 30 healthy women volunteers were received ±35 degrees of horizontal rotational perturbation and speed of 120 degrees per second from the sole while standing on the right leg in four conditions (external versus internal rotation of surface while the knee was in both extension and flexion position). Electromyography of knee muscles (vastus medialis and lateralis, medial and lateral hamstring and medial and lateral gastrocnemius) was measured to study the reaction time. Results: The reaction time of knee muscles during the perturbation was relatively long in this study (124 to 151 ms). It seems that muscles are recruited simultaneously in most conditions except in external rotation perturbation, with extension knee that the internal gastrocnemius muscle had significantly less delay time than the internal hamstring (P<0.05) and external quadriceps (P<0.05). The results show that most of these muscles do not react selectively and dependently on perturbation direction and knee position in response to horizontal rotational perturbation. Conclusion: In this study, little difference was seen in the reaction time of most knee muscles in all conditions. Thus in response to this type of perturbation, the knee muscles showed co-contraction.


2021 ◽  
Vol 29 (1) ◽  
Author(s):  
John C. Cho ◽  
Lauren Tollefson ◽  
Kenneth Reckelhoff

Abstract Objective The Thessaly test is a commonly used orthopedic test for meniscus tear evaluation. The study’s objective is to evaluate the degree of medial meniscal extrusion during different loading phases of the Thessaly test. Methods A convenience sample of 60 healthy knees (35 participants) was examined and the data sets were collected from October 8, 2018 through February 8, 2019. Sonographic measurement of the degree of physiologic extrusion of the medial meniscus deep to the medial collateral ligament was taken by two examiners at six different loading phases: supine, standing, 5° knee-flexion with internal (IR)/external (ER) rotation and 20° knee-flexion with IR/ER. The difference in meniscal extrusion by knee position was compared with ANOVA. Interexaminer reproducibility assessment was analyzed using limits of agreement. Results The mean meniscal extrusion for each position was—supine: 2.3 ± 0.5 mm, standing: 2.8 ± 0.8 mm, 5° IR: 2.3 ± 0.9 mm, 5° ER: 2.4 ± 0.7 mm, 20° IR: 1.9 ± 0.8 mm, and 20° ER: 2.3 ± 0.7 mm. Significant increase in extrusion was observed from supine to standing (p < 0.05) and from 20° IR to 20° ER (p = 0.015). Significant decreased measurement was observed from standing to 5° IR (p < 0.05), 5° ER (p < 0.05), 20° IR (p < 0.05) and 20° ER (p < 0.05). There is no significant change between 5° IR and 5° ER (p = 1.0). Agreement parameters revealed that the differences between examiner measurements were minimal; 75% of both examiners’ meniscal extrusion measurements were within 1.0 mm with 97% of measurements falling within 2.0 mm. Conclusion Our study’s novel findings showed various degrees of physiological extrusion of the medial meniscus in asymptomatic knees during the loading phases involved in the Thessaly test. Physiological MME does exist and should not be defaulted to pathologic meniscus as previously described. Agreement parameters suggest that measurement of meniscal extrusion during the Thessaly test is reproducible between different examiners.


2021 ◽  
Author(s):  
Sarah Hood ◽  
Lukas Gabert ◽  
Tommaso Lenzi

Powered prostheses can enable individuals with above-knee amputations to ascend stairs step-over-step. To accomplish this task, available stair ascent controllers impose a pre-defined joint impedance behavior or follow a pre-programmed position trajectory. These control approaches have proved successful in the laboratory. However, they are not robust to changes in stair height or cadence, which is essential for real-world ambulation. Here we present an adaptive stair ascent controller that enables individuals with above-knee amputations to climb stairs of varying stair heights at their preferred cadence and with their preferred gait pattern. We found that modulating the prosthesis knee and ankle position as a function of the user’s thigh in swing provides toe clearance for varying stair heights. In stance, modulating the torque-angle relationship as a function of the prosthesis knee position at foot contact provides sufficient torque assistance for climbing stairs of different heights. Furthermore, the proposed controller enables individuals to climb stairs at their preferred cadence and gait pattern, such as step-by-step, step-over-step, and two-steps. The proposed adaptive stair controller may improve the robustness of powered prostheses to environmental and human variance, enabling powered prostheses to more easily move from the lab to the real-world.


Author(s):  
Alberto Grassi ◽  
Piero Agostinone ◽  
Stefano Di Paolo ◽  
Gian Andrea Lucidi ◽  
Luca Macchiarola ◽  
...  

Abstract Purpose The aim of the present study was to trace knee position at the time of bone bruise (BB) and investigate how much this position departed from the knee biomechanics of an in vivo flexion–extension. Methods From an original cohort of 62 patients, seven (11%) presented bicompartmental edemas and were included in the study. 3D models of bones and BB were obtained from MRI. Matching bone edemas, a reconstruction of the knee at the moment of BB was obtained. For the same patients, knee kinematics of a squat was calculated using dynamic Roentgen sterephotogrammetric analysis (RSA). Data describing knee position at the moment of BB were compared to kinematics of the same knee extrapolated from RSA system. Results Knee positions at the moment of BB was significantly different from the kinematics of the squat. In particular, all the patients’ positions were out of squat range for both anterior and proximal tibial translation, varus–valgus rotation (five in valgus and two in varus), tibial internal–external rotation (all but one, five externally and one internally). A direct comparison at same flexion angle between knee at the moment of BB (average 46.1° ± 3.8°) and knee during squat confirmed that tibia in the former was significantly more anterior (p < 0.0001), more externally rotated (6.1 ± 3.7°, p = 0.04), and valgus (4.1 ± 2.4°, p = 0.03). Conclusion Knee position at the moment of Bone bruise position was out of physiological in-vivo knee range of motion and could reflect a locked anterior subluxation occurring in the late phase of ACL injury rather than the mechanism leading to ligament failure. Level of evidence Level IV


2021 ◽  
Author(s):  
Chin-Suk Cho ◽  
Lauren Tollefson ◽  
Kenneth Reckelhoff

Abstract ObjectiveThe Thessaly test is a commonly used orthopedic test for meniscus tear evaluation. The study’s objective is to evaluate the degree of medial meniscal extrusion during different loading phases of the Thessaly test. MethodsA convenience sample of 60 healthy knees (35 participants) was examined. Sonographic measurement of the degree of physiologic extrusion of the medial meniscus deep to the medial collateral ligament was taken by two examiners at six different loading phases: supine, standing, 5° knee-flexion with internal (IR)/external (ER) rotation and 20° knee-flexion with IR/ER. The difference in meniscal extrusion by knee position was compared with ANOVA. Interrater reliability assessment was analyzed using intraclass correlation coefficient. ResultsThe mean meniscal extrusion for each position was - supine: 2.3±0.5mm, standing: 2.8±0.8mm, 5° IR: 2.3±0.9mm, 5° ER: 2.4±0.7mm, 20° IR: 1.9±0.8mm, and 20° ER: 2.3±0.7mm. Significant increase in extrusion was observed from supine to standing (p<0.05) and from 20° IR to 20° ER (p=0.015). Significant decreased measurement was observed from standing to 5° IR (p<0.05), 5° ER (p<0.05), 20° IR (p<0.05) and 20° ER (p<0.05). There is no significant change between 5° IR and 5° ER (p=1.0). Interrater reliability of the measurements across the six positions was poor to moderate (0.35-0.57, p<0.05). ConclusionOur study’s novel findings showed clear dynamic changes during Thessaly test, which implies increase in compressive stress across the medial meniscus and a potential mechanism for pain generation during this test. Further testing is needed to address the poor-moderate reliability and confirm findings.


2021 ◽  
Vol 28 (1) ◽  
pp. 84-91
Author(s):  
Kwang Jun Lee ◽  
Kitaek Lim ◽  
Woochol Joseph Choi

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