共查询到20条相似文献，搜索用时 31 毫秒
1.
Salman Nazary-Moghadam Mahyar Salavati Ali Esteki Behnam Akhbari Sohrab Keyhani Afsaneh Zeinalzadeh 《The Knee》2019,26(1):88-96
Background
Several investigations have studied gait variability of individuals with anterior cruciate ligament (ACL) deficiency; however, the effect of dual-tasking on the gait variability of these individuals remained unclear. The aim of the present study was to determine the effect of gait speed and dual-tasking on knee flexion–extension variability in subjects with and without ACL deficiency.Methods
The knee flexion–extension Lyapunov exponent (LyE) was measured in 22 ACL-deficient (Mean±SD) (25.95?±?4.69?years) and 22 healthy subjects (24.18?±?3.32?years). They walked at three levels of gait speed in isolation or concurrently with a cognitive task.Results
Repeated-measure analyses of variance (ANOVAs) demonstrated that the interaction of group by gait speed was statistically significant. As the gait speed increased from low to high, the knee flexion–extension LyE significantly decreased for the subjects with ACL deficiency (effect size: 0.57, P?=?0.01). The interaction of group by cognitive load was not statistically significant (P?=?0.07). In addition, the ACL-deficient subjects had statistically slower reaction times than healthy subjects during the dual-task compared with the single-task condition.Conclusions
The ACL-deficient and healthy individuals had a tendency to maintain safe gait. It seems that the ACL-deficient subjects sacrificed the cognitive task more than the healthy individuals to pay more attention toward gait. Additionally, it seems that the gait speed was more challenging than cognitive load on the stride-to-stride variability in the individuals with ACL deficiency. 相似文献2.
Tiana Raoul Shahnaz Klouche Baptiste Guerrier Badr El-Hariri Serge Herman Antoine Gerometta Nicolas Lefevre Yoann Bohu 《The Knee》2019,26(1):155-164
Background
The decision to return to sport following anterior cruciate ligament (ACL) reconstruction should not only be based on time since surgery. This study aimed to assess, using isokinetic and neuromuscular (hops) testing in a large group, postoperative objective functional recovery of the knee. The secondary objective was to determine the relationship between psychological, functional scores, and these postoperative tests.Methods
This prospective study included athletes who underwent surgery between 2013 and 2016 for an isolated full-thickness ACL tear. They received a complete evaluation of functional performance of the knee by isokinetic tests performed on a dynamometer to measure quadriceps and hamstring strength, and neuromuscular assessment based on single-leg hop tests. The main judgment criterion was satisfactory functional recovery (yes/no) defined as a difference of ≤ 10% both in the quadriceps 60°/s and the single hop at a minimum of four months of follow-up.Results
A total of 234 athletes were analyzed. The mean age was 28.4?±?8.6?years. At 6.5?±?1.7?months mean follow-up, 44 (18.5%) patients had satisfactory functional recovery of the knee. The correlations between isokinetic/hop tests and the different scores were variable. During follow-up, two patients presented with a graft tear and two with a contralateral ACL tear, all in the group with unsatisfactory functional recovery.Conclusion
At a mean of six months after ACL reconstruction, objective functional recovery of the knee was generally unsatisfactory and this seemed to be a risk factor for recurrent tears.Level of evidence
IV; case series. 相似文献3.
David Latz Erik Schiffner Johannes Schneppendahl Konstantin Klein Lisa Oezel Lars Fabian Seiler Pascal Jungbluth Robert Alexander Kaufmann Joachim Windolf Sebastian Viktor Gehrmann 《The Knee》2019,26(1):33-39
Background
One of the most important activities of daily living is operating a motor vehicle. With increasing age the prevalence of musculoskeletal disorders such as knee osteoarthritis may interfere with an individual's ability to do so safely. Physicians are tasked with determining a patient's ability to drive and yet the necessary joint range of motion required for driving a car has not been characterized.Methods
The range of motion of the right and left knees was recorded using electrogoniometers in 20 healthy subjects while driving a car on three route types (a) city streets, b) country roads and c) highways). Special emphasis was placed on the left knee associated with changing a gear.Results
The range of motion while driving is 40–80° for the right and 20–85° flexion for the left knee. A significant difference was noted for each side (p?<?0.01) with a higher flexion occurring in the left knee (p?<?0.01). The average position of the knee while changing a gear (beginning, maximum, ending) was: right: 55°±10°, 62°±10°, 53°±10°; left: 67°±7°, 39°±8°, 66°±8° (mean flexion±standard deviation).Conclusion
This study characterized the knee range of motion that occurs while driving a car. Our data suggests that common driving activities such as accelerating a vehicle or braking can be achieved with the right knee through a limited range of motion. The greater range of motion and the higher flexion of the left knee are mainly attributed to the gear changing. The present data may benefit physicians in their evaluation of driving capability. 相似文献4.
Jae S. You Anne R. Wright Ian Hasegawa Brandon Kobayashi Matthew Kawahara Jordan Wang Cass K. Nakasone 《The Knee》2019,26(1):228-239
Background
Tibial osseous defects can present a serious challenge in primary total knee arthroplasty. We describe a technique of using porous tantalum cones along with primary arthroplasty implants to address large tibial osseous defects in primary total knee arthroplasty and present the short-term results.Methods
We present 17 cases (15 patients) in which primary total knee implants and porous tantalum cones were used to address large tibial bony defects. Clinical results were evaluated using Knee Society Scores, pre- and postoperative knee range of motion, and serial radiographs.Results
At an average of 3.5?years of follow-up, all 17 knees had functioning implants with stable metaphyseal cones demonstrating radiographic evidence of osteointegration. At a minimum follow-up of two years, no patient had signs of osteolysis, instability, infection, or systemic complications. All 15 patients had excellent results with an average post-operative Knee Society Score of 94.6. Knee flexion improved by an average of 12.0° and knee extension improved to neutral in all patients.Conclusion
Primary total knee arthroplasty with porous tantalum cone augmentation produced excellent short-term results and should be considered an effective method for addressing large tibial osseous defects in primary total knee arthroplasty. 相似文献5.
Background
While surgical reconstruction restores mechanical stability following anterior cruciate ligament (ACL) rupture, many experience early-onset osteoarthritis despite surgery. Neurophysiological changes are hypothesized to contribute to knee osteoarthritis progression. Proprioceptive deficits have been reported following ACL injury/reconstruction; however, vibration perception threshold (VPT) has been less studied. This study explored relationships between pain, VPT, proprioception, function, and strength following ACL-reconstruction.Methods
Twenty individuals (27?±?6 years; 10 males) (standard deviation) status-post ACL-reconstruction were compared with a control group. Measurements included VPT, proprioception (threshold to detect passive movement), pain, function (Knee Outcome Survey (KOS)) and isometric quadriceps strength. Group differences were assessed using Mann-Whitney U tests, side-to-side differences with Wilcoxon Signed Rank tests, and associations evaluated using Spearman correlations.Results
The ACL-reconstruction group had minor functional deficits (15?±?11%) and resting pain (1.8?±?1.7). Impaired VPT and proprioception (hypoesthesia) were demonstrated on surgical compared to contralateral and control limbs (p?≤?0.008). Proprioception was significantly different between contralateral and control knees, but not VPT. Surgical knee proprioceptive deficits and VPT deficits were positively correlated (ρ?=?0.462, p?=?0.047) but not in controls (ρ?=??0.042, p?=?0.862). Strength was negatively correlated to pain (ρ?=??0.589; p?=?0.006), but not to KOS scores, proprioception or VPT (p?≥?0.099).Conclusion
Proprioceptive deficits following ACL injury have been ascribed to loss of afferent input from the torn ligament. Alternatively, multi-modality as well as contralateral sensory deficits suggest a spinal/supraspinal source of neurophysiological findings which may predispose to early osteoarthritis.Level of evidence
III. 相似文献6.
Background
As assessment with inertial-measurement-units (IMUs) increases in research and in clinics, it is important to be aware of the repeatability of these sensors. The objectives of this experiment were to evaluate the measurement repeatability of IMU joint angles using a repeatable robot controller and an anthropomorphic leg phantom and to determine effects of joint speed and sensor positioning on the angles collected by these sensors. Comparisons to an electro-goniometer and three-dimensional (3D) motion capture cameras were also completed.Methods
Two dual-IMU setups (posterior and lateral) were tested concurrently with an electro-goniometer and 3D motion capture cameras using a repeatable robot controller and a leg phantom. All modalities were attached to the phantom, which was flexed 10 times using a pre-programmed motion pathway during each test. Mean angles were compared across tests. Effects of joint speed, sensor re-positioning, and anatomical placement of the sensors on repeatability were assessed.Results
Re-positioning caused greater deviation to the maximum and minimum angles than differences in speed. Overall, the means?±?standard deviations, and 95% confidence intervals of the maximum angles across all tests for the 3D camera markers, electro-goniometer, posterior IMUs, and lateral IMUs were 119.4?±?0.3° (119.4, 119.5), 112.4?±?0.5° (112.3, 112.5), 116.2?±?2.4° (115.7, 116.7), and 118.3?±?1.1° (118.1, 118.6).Conclusions
Both posterior and lateral IMU setups demonstrated acceptable repeatability in measurement of range of motion that was advantageous to manual goniometer methods. Posterior and lateral IMU setups demonstrated overlapping standard deviations about their means. 相似文献7.
Background
Total knee arthroplasty (TKA) remains the gold standard for end-stage knee osteoarthritis. The prevalence of stiffness after this procedure described in literature varies from 1.3% to 5.3%. The causes of arthrofibrosis after total knee arthroplasty are multifactorial. Revision TKA is a successful procedure when performed for loosening, instability, mechanical implant failure, or infection. The results of revision TKA for idiopathic arthrofibrosis and stiffening are however less favorable.Purpose
It has been the authors' impression that the poor results in arthrofibrosis could be in part related to the use of traditional PS or CCK-type revision implants. Our hypothesis is that better results can be achieved in case a rotating hinge design (RHK) is used. The reason could be that RHK designs allow for much more aggressive capsuloligament debridement and therefore more adequate fibrosis removal, while securing optimal implant stability, tibiofemoral rotational freedom, and flexion-extension space stability. The purpose of our study was to investigate in our database whether this hypothesis is correct.Methods
Retrospectively, 40 patients with the defined range of knee motion were identified. Patients with underlying mechanical malalignment, component malposition, soft-tissue imbalance or infections were excluded. Twenty-two patients received a hinged-type prosthetic device (18 Zimmer RHK, four Stryker RHK) and 18 patients received a less constrained condylar type prosthetic device (17 Legion CCK, one Vanguard CCK).Results
Preoperative data were similar for RHK as CCK-type implants except for knee pain score, which was significantly worse for the RHK group (36 vs 44, p?=?0.049). At two years of follow-up, compared to CCK, the RHK group demonstrated significantly better postoperative results for knee function scores (68.9 vs 54.2, p?=?0.0015), knee function improvement (22.8 vs 4.8, p?=?0.0015), knee pain improvement (26.4 vs 9.4, p?=?0.0050), greater maximal flexion (99.9° vs 81.4°, p?=?0.0005), better maximal extension (? 1.9° vs ? 6.2°, p?=?0.0447), greater flexion gain (35.8° vs 14.2°, p?=?0.0002), and greater extension gain (8.6° vs 2.0°, p?=?0.0083).Conclusion
Our data show that revision arthroplasty of the stiff knee using a rotating hinged device can provide excellent results in selected cases. To date, this is the first study to describe the difference in outcome between revision total knee arthroplasty for idiopathic arthrofibrosis using a hinged or a constrained condylar knee device. 相似文献8.
Cody Goessl Paul Estabrooks Wen You Denise Britigan Armando DeAlba Fabio Almeida 《Patient education and counseling》2019,102(5):968-975
Objective
This study evaluates the effectiveness of technology versus in-person, group-initiated diabetes prevention to enhance comprehension of learning objectives between patients with differing health literacy (HL).Methods
Evidence-based content through either a DVD (n?=?217) or in-person, group class (n?=?225) to initiate the intervention. A teach-back call was used to assess comprehension of, and reinforce, learning objectives. Chi-squared was used to determine differences between conditions (DVD vs Class) and HL levels (High n?=?361 vs. Low n?=?81) and regression analyses were used to examine relationships.Results
DVD participants performed significantly better across teach back questions (15.4?±?2.5 v. 14.8?±?2.6, p?<?0.01), demonstrated comprehension in fewer teach-back rounds (1.9?±?0.7 v. 2.1?±?0.7, p?<?0.01), and answered more questions correctly on the first try (4.2?±?1.6 v. 3.4?±?1.8, p?<?0.01). Models for HL levels and modality by HL level were statistically significant (p?<?0.01) favoring the DVD.Conclusion
Initiating a diabetes prevention program with the use of a DVD appears to be a superior option to in-person, class sessions. Teach-back and teach-to-goal strategies enables participants of both high and low health literacy levels to receive and confirm mastery of diabetes prevention objectives.Practice Implications
A teach-back call may improve information uptake increasing the likelihood of health behavior uptake. 相似文献9.
Background
The purpose of this study was to characterise the histopathological changes in the infrapatellar fat pad (IPFP) in the early stage of patellofemoral osteoarthritis (PFOA).Methods
Sixty-four New Zealand white rabbits were randomly divided into experimental (n?=?24), sham (n?=?16), and control groups (n?=?24). In the experimental group, denoted as the patellar ligament uneven shortening group (US group), the patellar ligament (PL) was folded eight millimetres and sutured. After eight weeks, all animals were euthanised, and magnetic resonance imaging (MRI) evaluation, wet IPFP weight measurement, and histopathological and immunohistochemistry analysis were performed to analyse the histopathological changes in the IPFPs.Results
The maximum cross-sectional area (CSA) of the IPFPs in the sagittal position of MRI in the control group, sham group, and US group were 45.50?±?7.19?mm2, 45.88?±?6.60?mm2 (vs. control group, P?=?0.907), and 53.83?±?8.24?mm2 (vs. control group, P?=?0.015; vs. sham group, P?=?0.035), respectively. The MRI intensity of the IPFPs in the control group, sham group, and US group were 115.53?±?28.85, 108.53?±?26.73 (vs. control group, P?=?0.589), and 154.52?±?18.48 (vs. control group, P?=?0.002; vs. sham group, P?=?0.002), respectively. The wet weight of the IPFPs in the control group, sham group, and US group were 0.32?±?0.05?g, 0.32?±?0.04?g (vs. control group, P?=?0.895), and 0.38?±?0.06?g (vs. control group, P?=?0.017; vs. sham group, P?=?0.033), respectively. The Osteoarthritis Research Society International (OARSI) scores of the IPFPs in the US group were 6.00?±?1.91, which was higher than the scores of 2.50?±?2.02 (P?<?0.001) in the control group and of 2.75?±?1.67 (P?=?0.001) in the sham group.Conclusions
The histopathological changes of the IPFPs as determined via MRI and microscopic structure appeared to occur much earlier than cartilage damage in PFOA. Furthermore, detecting and treating the IPFP changes may offer aid in the diagnosis and treatment of PFOA. 相似文献10.
Background
The purpose of this retrospective cohort study was to investigate the influence of parameters of malalignment on knee function 5?years post TKA and, additionally, to explore alterations in patellar height after TKA.Methods
All 661 patients undergoing TKA between 2010 and 2011 were considered for inclusion. Preoperative and 1-year postoperative short-leg radiographs were assessed for malalignment parameters: coronal tibial angle (cTA), sagittal tibial angle (sTA), femoral flexion angle (FFA) and mediolateral tibial mismatch. Patellar height was measured using the modified Insall-Salvati ratio. We determined improvements in knee function utilizing the Knee Society Score (Function score, KSS-F), Oxford Knee Score (OKS) and Algofunctional index (AI). Influences of malalignment parameters were analyzed univariate and selected (p?<?0.10) for multivariate linear regression analysis. Inter-observer reproducibility was assessed by test–retest analysis of 30 randomly selected radiographs and calculation of an intra-class correlation coefficient (ICC) for all radiographic parameters.Results
Three-hundred and four patients were included. Multivariate regression showed degrees of cTA malalignment to be significantly associated with only the KSS-F (β?=?? 3.52). Correction of coronal deformity was stronger associated with knee function (KSS-F β?=?2.81; AI β?=?? 0.36). Patellar height was significantly reduced after TKA (1.51 vs 1.44). Decrease of patellar height was weakly associated with the OKS (β?=?10.69). ICC scores were: cTA 0.81, sTA 0.57, IS 0.72, FFA 0.75.Conclusion
Postoperative coronal tibial plate alignment and correction of preoperative coronal deformity are associated with improved knee function 5?years post TKA. Decrease in patellar height was weakly associated with knee function. Short-leg radiography can be a sufficient screening tool for prosthesis alignment. 相似文献11.
Takashi Kitagawa Junsuke Nakase Yasushi Takata Kengo Shimozaki Kazuki Asai Hiroyuki Tsuchiya 《The Knee》2019,26(1):14-19
Background
Patellar tendinopathy is difficult to successfully treat. This study aimed to characterize the pathological changes of the infrapatellar fat pad (IPFP) in patellar tendinopathy (PT), and to investigate the influence of PT on the development of fibrotic changes in the IPFP.Methods
Forty male Wistar rats were randomly divided into PT (n?=?20) and control groups (n?=?20). Bacterial collagenase I (patellar tendinopathy group) or saline (control) was injected, intratendinous, into the patellar tendon. Rats were sacrificed at week 12. The whole knee joint was sagittally sectioned and stained with hematoxylin–eosin and Masson's trichrome. The IPFP samples were graded according to cellularity, fibrosis, and vascularity. The whole IPFP and blue-stained area was measured. Mann–Whitney U tests were used to compare the between-group differences of each score and quantitative value.Results
Scores for cellularity were three (2–3) and 0 (0–1) in the PT and control groups, respectively (P?<?0.01). Mean scores for fibrosis were two (1–3) and 0 (0–1) in the PT and control groups, respectively (P?<?0.01). Mean scores for vascularity were two (2–3) and one (1–1) in the PT and control groups, respectively (P?<?0.01). There was a significant difference in the total score between the PT and control groups (seven (5–8) and two (1–3), respectively) (P?<?0.01). Average percentages of the fibrous area of the IPFP were 38.2?±?26.5% and 11.2?±?3.9% in the patellar tendinopathy and control groups, respectively (P?<?0.01).Conclusion
The IPFP in the patellar tendinopathy group showed greater cellularity, fibrosis, and vascularity than the control group. 相似文献12.
Annemie Smeets Bart Malfait Bart Dingenen Mark A. Robinson Jos Vanrenterghem Koen Peers Stefaan Nijs Styn Vereecken Filip Staes Sabine Verschueren 《The Knee》2019,26(1):40-51
Background
There is limited evidence on neuromuscular risk factors for anterior cruciate ligament (ACL) injuries, with most work mainly focusing on hamstrings and quadriceps muscle strength. This prospective pilot study explored if neuromuscular activation patterns of the quadriceps and hamstrings during a drop vertical jump influence ACL injury risk.Methods
Forty-six female athletes performed a drop vertical jump at baseline. Injuries were monitored throughout a one-year follow-up. Neuromuscular activation patterns of the vastus medialis, vastus lateralis, hamstrings medialis and hamstrings lateralis, and selected landing kinematic and kinetic profiles (knee flexion, knee abduction and hip flexion angles, and knee abduction moments), were compared between athletes who sustained a non-contact ACL injury and those who remained injury free. Electromyogram vector fields were created to represent neuromuscular activation patterns of muscle pairs around the knee joint rather than only considering individual muscle activations, and compared using Statistical Parametric Mapping.Results
Four athletes sustained an ACL injury. Significantly greater {hamstrings medials, hamstrings lateralis}, {vastus lateralis, hamstrings lateralis} and {hamstrings lateralis, vastus medialis} activations, mainly due to greater hamstrings lateralis activation, were found in the injured group around peak loading and just before take-off (P?<?0.001). No group differences were found in knee flexion, knee abduction and hip flexion angles, or knee abduction moments.Conclusions
This pilot study revealed initial evidence that athletes already showed altered neuromuscular activation patterns prior to sustaining an ACL injury, namely increased lateral and posterior muscle activations. 相似文献13.
Objectives
To investigate the effects of various diets on structure and function of the bladder in both normal and obstructed bladders of male Wistar rats.Methods
Sham-operated rats and rats with experimentally-induced bladder outlet obstruction (BOO) were fed with standard rats’ feed (control), High-carbohydrate (HCD), High-fat (HFD) and High-protein (HPD) diets. Feeding was continued for 4 weeks after BOO surgery. Bladder weight, detrusor contractility, Rho-Kinase (ROK) and Myosin Light Chain Kinase (MLCK) expressions were determined using standard methods.Results
In comparison with control, bladder weight was increased in HFD (164?±?9?mg), BOO (437?±?21?mg), HFD-BOO (523?±?19?mg) and HPD-BOO (268?±?18?mg). Detrusor contractility was reduced in BOO and HFD-BOO. The ROK- I and II expressions were high in HCD-BOO and low in HPD-BOO but ROK-I was also elevated in BOO. However, MLCK increased only in HCD-BOO.Conclusion
The results of the study reveal that diets with varying macronutrient compositions have variable effects on the bladder with and without obstruction. High-fat diets especially, affect detrusor morphology and function in both obstructed and unobstructed bladders. 相似文献14.
Andrea Antonio Maria Bruno Alexander Kirienko Andrea Peccati Paolo Dupplicato Massimo De Donato Enrico Arnaldi Nicola Portinaro 《The Knee》2017,24(1):91-99
Background
Currently, the main indication for knee arthrodesis is septic failure of a total knee arthroplasty (TKA). The purpose of this study was to evaluate the results of knee arthrodesis by circular external fixation performed in the treatment of TKA failure in which revision arthroplasty was not indicated.Methods
The study involved 19 patients who underwent knee arthrodesis by the Ilizarov method. Clinical and functional assessments were performed, including Knee Society Score (KSS). A postoperative clinical and radiographic evaluation was conducted every three months until the end of the treatment. Postoperative complications and eventual leg shortening were recorded.Results
KSS results showed a significant improvement with respect to the preoperative condition. Of the 16 patients in the final follow-up, 15 patients (93.7%) achieved complete bone fusion. Major complications occurred in patients treated for septic failure of TKA and most occurred in patients over 75 years of age; the mean final leg shortening was four centimeters.Conclusion
In our experience, the Ilizarov method is effective for performing a knee arthrodesis in the case of extensive bone loss. At the same time, it is possible to correct the associated leg deformities or limb length difference. In addition, only the Ilizarov method provides a mechanical stimulus for bone formation and improves the quality of the bone and of the microcirculation, which enhances the host response against infection. Despite these attributes, knee arthrodesis by the Ilizarov method must be considered a ‘salvage procedure’ in cases of severe outcomes from knee surgery in which revision arthroplasty is not indicated. 相似文献15.
Background
The effect of the changes in the femoral posterior condylar offset (PCO) on anterior–posterior (AP) translation and internal–external (IE) rotation in cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) remains unknown. The purpose of this study was to compare the kinematics in CR and PS TKA with respect to the difference in prosthetic design and PCO change through a computational simulation.Methods
We developed three-dimensional finite element models with the different PCOs of ± 1, ± 2 and ± 3?mm in the posterior direction using CR and PS TKA. We performed the simulation with different PCOs under a deep knee bend condition and evaluated the kinematics for the AP and IE in CR and PS TKA.Results
The more tibiofemoral (TF) translation in the posterior direction was found as PCO translated in posterior direction for both CR and PS TKA compared to the neutral position. However, the change of the AP translation with respect to the PCO change in CR TKA was greater than PS TKA. The more TF external rotation was found as PCO translated in the anterior direction for both CR and PS TKA compared to the neutral position. However, unlike the TF translation, the TF rotation was not influenced by the PCO change in both CR and PS TKA.Conclusion
The PCO magnitude was influenced by a postoperative change in the kinematics in CR TKA although a relatively smaller effect was observed in PS TKA. Hence, surgeons should be aware of the PCO change, especially for CR TKA. 相似文献16.
Background
A large majority of anterior cruciate ligament (ACL) injuries are non-contact, most often occurring during a landing or change of direction. Recent research indicates that cognitive factors may be involved in non-contact ACL injuries. The aim of this study was to determine if a game-situation perceptual–cognitive load leads to altered landing kinematics in physically fatigued female athletes.Methods
Nineteen female recreational athletes were recruited to perform a series of jumping and landing trials. In a first phase, eight trials were performed in an isolated condition and eight were performed while participants performed a perceptual–cognitive task. Before a second identical phase, participants underwent a muscular fatigue protocol. Knee-joint kinematics were recorded and compared between conditions using paired t-tests.Results
Muscle fatigue led to statistically significant increases in peak knee abduction and peak internal knee rotation as well as a decrease in maximum knee flexion, when comparing conditions without the perceptual–cognitive task. The perceptual–cognitive task had no statistically significant effect on any knee rotations, either pre- or post-fatigue. However, a subgroup of 12 athletes showed a significant increase in knee abduction in the presence of the perceptual–cognitive task, only in the fatigued condition.Conclusion
A perceptual–cognitive task combined with muscle fatigue alters knee kinematics of landing for a subset of recreational athletes, potentially increasing the risk of ACL rupture. Further studies are necessary to confirm this finding and to identify characteristics of at-risk individuals to target them for injury prevention protocols. 相似文献17.
Ken Dewitte Marc Claeys Emeline Van Craenenbroeck Koen Monsieurs Hein Heidbuchel Vicky Hoymans Tibor Stoop 《Pathophysiology》2019,26(1):53-59
Aims
We explored the effect of remote ischaemic conditioning (RIC) on endothelial function and on circulating mediators.Methods and results
In 20 healthy male volunteers (mean age 31?±?10 years), flow-mediated dilation (FMD) was measured before and after 20?min of arm ischaemia, followed by reperfusion. Remote ischaemic conditioning (RIC) was performed by applying 3 cycles of 5?min of ischaemia of the leg at the onset of index arm ischaemia. Each volunteer underwent the IR-induced vascular injury protocol with and without RIC in a crossover study design.In the control group, IR significantly reduced FMD (5.9?±?2.9% before IR vs. 2.2?±?3.7% after IR; p?<?0.001). This effect was significantly attenuated by performing RIC (FMD of 5.5?±?3.1% before IR vs. 4.0?±?3.4% % after IR; p for interaction?=?0.01). Serum levels of SOD and ADMA increased significantly whereas MCP-1 and VEGF levels decreased significantly.Only changes in SOD levels were significantly related to the degree of RIC induced protection (r²?=?0.34; p?=?0.018).Conclusion
RIC has protective effects against endothelial IR injury. Our biomarker study suggests that anti-oxidative stress mediators, such as SOD, seem to be more involved in the pathogenesis of RIC-induced protection in humans than angiogenesis factors or chemo-attractant cytokines. 相似文献18.
Jesse C. Christensen Ryan L. Mizner K. Bo Foreman Paul C. LaStayo Christopher L. Peters Christopher E. Pelt 《The Knee》2019,26(1):79-87
Background
Nearly all patients with total knee arthroplasty show aberrant movement patterns during tasks requiring greater joint demand compared to matched peers. Greater movement compensation leads to increased loading onto other joints, decreased functional capacity and limited reserve for independence later in life. Understanding how preoperative predictors contribute to postoperative aberrant movement patterns is needed to make better decisions for patients considering total knee arthroplasty.Methods
Forty-seven patients were tested preoperatively and six months following primary total knee arthroplasty. Demographic (age, sex, body mass), self-reported (knee pain, perception of physical performance, physical activity level), physical performance (quadriceps strength, lower limb power and timed stair climbing) and surgical metrics were collected as predictor variables. Three-dimensional models based on joint mechanic asymmetry during a decline walking task were collected at six months postoperatively. Decline walking is a preferred means to assess the surgical knee's contribution to limb performance during high-demand tasks. Bootstrap inclusion fraction was employed to compare the stability of each predictor variable prior to the final regression model.Results
Preoperative quadriceps strength (β?=?0.33; p?=?0.04) showed a significant relationship with knee extensor angular impulse during loading phase. No other predictor variable had any meaningful relationship with aberrant movement patterns (p?>?0.05).Conclusion
Our findings highlight patients' preoperative quadriceps strength as a meaningful predictor of postoperative performance. Preoperative quadriceps strength should be addressed when considering the knee's ability to contribute to higher demanding mobility tasks following surgery. 相似文献19.
20.
Matthias Steinwachs Nicola Cavalcanti Santhosh Mauuva Venkatesh Reddy Clement Werner Daniel Tschopp Hema N. Choudur 《The Knee》2019,26(1):174-184