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IJERPH
10.3390/ijerph17218208
Wilczyński, B.
Zorena, K.
Ślęzak, D.
Dynamic Knee Valgus in Single-Leg Movement Tasks. Potentially Modifiable Factors and Exercise Training Options. A Literature Review
Bartosz Wilczyński
1,2,* ,
Katarzyna Zorena
Daniel Ślęzak
Centre of Rehabilitation and Training "Fizjo-world", 81-537 Gdynia, Poland
Department of Immunobiology and Environment Microbiology, Medical University of Gdańsk, Dębinki 7, 80-211 Gdańsk, Poland
Departament of Medical Rescue, Medical University of Gdańsk, Dębinki 7, 80-211 Gdańsk, Poland
Int. J. Environ. Res. Public Health 2020, 17(21), 8208; https://doi.org/10.3390/ijerph17218208
Received: 28 September 2020 / Revised: 29 October 2020 / Accepted: 4 November 2020 / Published: 6 November 2020
(This article belongs to the Special Issue Physical Rehabilitation and Sports Medicine of Human Movement)
Dynamic knee valgus (DKV) as an incorrect movement pattern is recognized as a risk factor for lower limb injuries. Therefore, it is important to find the reasons behind this movement to select effective preventive procedures. There is a limited number of publications focusing on specific tasks, separating the double-leg from the single-leg tasks. Test patterns commonly used for DKV assessment, such as single-leg squat (SLS) or single leg landings (SLL), may show different results. The current review presents the modifiable factors of knee valgus in squat and landing single-leg tests in healthy people, as well as exercise training options. The authors used the available literature from PubMed, Scopus, PEDro and clinicaltrials.gov databases, and reviewed physiotherapy journals and books. For the purpose of the review, studies were searched for using 2D or 3D motion analysis methods only in the SLL and SLS tasks among healthy active people. Strengthening and activating gluteal muscles, improving trunk lateral flexion strength, increasing ROM dorsiflexion ankle and midfoot mobility should be taken into account when planning training programs aimed at reducing DKV occurring in SLS. In addition, knee valgus during SLL may occur due to decreased hip abductors, extensors, external rotators strength and higher midfoot mobility. Evidence from several studies supports the addition of biofeedback training exercises to reduce the angles of DKV.
Keywords: knee kinetics; knee abduction; single-leg squat; injury prevention; anterior cruciate ligament; sport performance knee kinetics; knee abduction; single-leg squat; injury prevention; anterior cruciate ligament; sport performance
A key aspect of protecting people practicing both amateur and professional sport is injury prevention. For decades, researchers have been trying to identify modifiable risk factors and to create and implement interventions to minimize or eliminate these factors. An example of the work put into the research into the implementation of injury prevention is the model of Van Mechelen et al. 1992. Proposes four steps, the first concerns the determination of the order of magnitude of the problem in the population. The second step concerns the identification of the etiology and mechanisms of the injury. The next step is to introduce preventive measures to evaluate the effectiveness of the preventive measure in the final step [1,2]. Attempts to identify risk factors are due to the increase in the number of injuries such as the anterior cruciate ligament (ACL) rupture, and prevalent conditions such as patellofemoral pain (PFP) among athletes in recent years [3,4,5].
The complexity of the injury problem requires a multifactorial and multidirectional approach, bearing in mind injury exposure, which is often changing over time [6,7,8]. The coexistence of external risk factors such as training errors or the environment, and internal risk factors such as reduced muscle strength, and limited range of motion are also a challenge in this problem. To better control these factors, one must know the potential causes creating or predisposing their occurrence. It should be mentioned that one risk factor does not give complete certainty to the occurrence of an injury. However, interactions with other determinants allow the shaping of the profile of a person with the likelihood of injury [7].
Dynamic Knee Valgus
Dynamic knee valgus (DKV) is a movement pattern of the lower limb, potentially comprised of a combination of adduction and internal rotation of the femur, abduction of the knee, anterior tibial translation, external tibial rotation and ankle eversion [9]. During this pattern, medial knee displacement is observed, beyond the foot-thigh line, which indicates knee valgus movement [10]. DKV is one of the predisposing factors for acute and chronic injuries, such as non-contact ACL injury and the occurrence of PFP [11,12]. Both video analysis of athletes during injury games [13,14] as well as cadaveric studies [15,16] emphasize the mechanism of knee valgus as a mechanism of ACL injury. The differences in the above cases occur in the rotation of the tibia. Cadaveric studies show the mechanism of ACL strain during knee valgus with internal rotation [15,16]. The iliotibial band as an extension of the tensor fasciae latae and gluteus maximus muscles help to stabilize the knee joint in the frontal plane. However increased tension in tensor fascia latae can affect tibial abduction, resulting in knee valgus [17]. Moreover, in the Cadaveric study under non-weight-bearing conditions, it was proved that the greater the load on the iliotibial band, the greater the anterior tibial translation and the tibial valgus rotation increased, which may have an impact on dynamic knee valgus [18]. In addition, mechanoreceptors located in the tendons (Golgi tendon organ) and in the muscles (muscle spindles), which are responsible for the reflex function, assist in the positioning of the limbs [19]. Disturbances of these mechanisms, which are proprioceptive feedback system may contribute to ACL injuries [20]. Previous ACL trauma is a risk factor for recurrence in the same or the contralateral limb ranging from 6 to 32% [21]. Studies are suggesting that after the first ACL injury, an increased risk is associated with a change in movement control and an increase in joint load asymmetry, which may be one of the causes of the second ipsilateral or contralateral ACL injury [22]. Furthermore, dynamic valgus is responsible for patella maltracking, and in case of overload resulting from increased activity for example, it also increases stress on the patellofemoral joint and retinaculum causing PFP [23]. The example of the correct movement pattern and dynamic knee valgus is presented in Figure 1.
The authors, in their works on the knee valgus motion tasks, describe this inappropriate motor pattern as well as a knee medial foot position (KMFP), knee abduction or valgus knee excursion, differentiating in some cases peak or maximum valgus knee, and in landing tasks also detailing the assessment in the initial contact (IC) phase or the phase of maximum knee flexion [24]. The gold standard for the kinematic evaluation of the DKV pattern is the three-dimensional (3-D) method of analysis. Due to the lack of specialized equipment, a substitute, acceptable assessment method can be two-dimensional (2-D) analysis in the frontal plane motion [25,26]. Publications using these methods have been evaluated in the current review. The online databases from PubMed, Scopus, PEDro and clinicaltrials.gov, and physiotherapy journals and books were searched using keywords such as "dynamic knee valgus", "knee abduction", "knee kinetics", "frontal plane projection angle" and "knee biomechanics" in combination with "injury prevention", "exercise", "risk factors", "anterior cruciate ligament", "patellofemoral pain", "single leg squat" and "single leg landing". Studies were included in the review only when dynamic valgus was assessed by the 2D or 3D method in SLS or SLL tests.
Despite evidence of DKV among patients with PFP [23,27,28] and after ACL injury [29], these studies were not considered in the review to focus on predictive values of healthy people. It is important to know the causes for the occurrence of DKV to help design an effective intervention to reduce the medial displacement of the knee.
Therefore, the purpose of the work is to conduct a review of the new literature regarding the potentially modifiable factors responsible for the dynamic knee valgus pattern in single-leg tasks. Furthermore, exercise intervention options for DKV reduction have been described.
2. Relationship between Squat and Landing on a Single-Leg and Double-Leg in Terms of Knee Valgus
The most common test for DKV assessment is the drop vertical jump test (DVJ), which involves a double-leg landing (DLL) [30,31]. Landing and squat testing tasks on both feet have gained interest over recent years due to research into the causes of ACL injuries [9,32]. The single-leg landing (SLL) and squats (SLS) were used to assess the biomechanics of the lower limb associated with ACL loading and the risk of PFP injuries [33,34]. Both squat and landing tasks consist of descending and ascending phases. They use the same movement pattern (i.e., flexion and extension of the torso, hips, knees and ankles in the sagittal plane). On the other hand, the squat, compared to landing, is characterized by a lower external load and slower movement, which seems to be an easier motor task to perform. It is worth paying attention to this because differences between these movement patterns can cause significant differences in the results for the knee valgus angles [29,35].
Considering knee valgus in these movement tasks, results may vary. There is evidence from research that confirmed the positive correlation of moderate to strong knee valgus between SLL, SLS and DLL [31,36,37]. However, in the study of Munro et al. 2017, the valgus angle of the FPPA was statistically significantly larger in the SLS test than in SLL (p < 0.001), and in SLS than in DVJ (p < 0.001) in the studied group of young basketball players [31]. Quite the opposite, Donohue et al. 2015, showed knee valgus results in 17 male and 17 female recreational athletes, where double-leg squat had the highest maximum valgus angles, followed by DLL, SLL, and the smallest SLS (p < 0.00001) [35]. Additionally, in the study of Taylor et al., 2017, comparing lower limb biomechanics in the DLL vs. SLL test in 15 recreationally active females, there were no differences in knee valgus angles (p > 0.05). Despite statistically significant changes in kinetics, differences were not visible for hip flexion, hip adduction, hip internal rotation, knee flexion or knee external rotation [37]. Due to the above conclusions from the research on knee valgus in landing and squat movement tasks, the authors of this review believe that single-leg tests should be separated from double-leg tests to better understand the causes of DKV.
The current review focuses solely on publications on single-leg movement tasks, mainly single-leg squat and single-leg landing in the sagittal plane for several reasons. First, knee valgus in the standing position on one leg with loss of balance is the main observed pattern during lower limb injuries [14]. Second, the vast majority of ACL injury cases occur during single-leg landing tasks [38,39,40]. Besides, single-leg tasks are more demanding movements than double-leg, which makes it easier to identify people with a higher risk of injury [10]. Finally, DKV is considered for single-legged tasks for specification and better practical implication.
3. Selected Modifiable Factors of Dynamic Knee Valgus
3.1. Impact of the Neuromuscular Trunk Control on Knee Kinetics
The "trunk dominance" term proposed by Hewett et al., 2009, as one of the causes of ACL injuries, is associated with dynamic knee valgus [41]. A lack of adequate neuromuscular trunk control and excessive lateral flexion of the trunk in the frontal plane predisposes to a shift in the center of gravity of the body away from the knee during squatting or landing. Shifting the center of gravity laterally to the knee joint is also associated with shifting ground reaction forces (GRF) in the same direction, which consequently causes knee valgus movement [42]. It was confirmed by Nakagawa et al. 2015, who observed an excessive ipsilateral lateral torso lean that was significantly correlated (r = 0.49, p < 0.01) with greater knee valgus in a group of thirty healthy participants. Electromagnetic sensors located on the sternum, sacrum and in the center of the hip allow the trunk angle to be determined during the SLS test [43]. For the above reasons, the hypothesis relating to the torso is taken into account when considering the causes of knee valgus in single-leg tasks. Neuromuscular trunk control is inseparably linked to the muscles of the torso. Core muscles refer, among others, to the stabilizing forces generated by the muscles of the hip, pelvis, and torso. When the body is loaded on one leg, hip abductor muscles work with the quadratus lumborum muscle to keep the position of the pelvis horizontally and prevent excessive adduction of the femur [44]. There is evidence that in the case of greater trunk lateral flexion muscle strength in side-lying planks, participants of both sexes show lower dynamic knee valgus angles in SLS [43,45,46]. The characteristics of studies in causes of dynamic knee valgus are presented Table 1. However, the large complicity of muscles of the hip abductors supporting the isometric lateral trunk flexion should be emphasized [47]. There is a need for more research on the effect of torso muscle strength on DKV. However, current publications suggest that the weak lateral trunk flexor muscles appear to be one of many predisposing factors for DKV in SLS.
3.2. Hip Strength and Muscle Activation as Causes of the Incorrect Movement Pattern of the Knee
The hip works as a proximal mechanism playing a key role in the neuromuscular control and compensation of excessive movements of the lower limb kinematic system [48]. Movement of the hip joints depends mainly on the work of the gluteus muscles. When considering the functions of the gluteus, it should be noted that they work in contradiction to the dynamic knee valgus movement by hip abduction and external rotation [49]. In addition, weakened hip abductors may affect the compensatory movement of pelvic drop and lateral torso displacement [50]. To date, several studies have shown a link between the occurrence of dynamic valgus in single-leg tasks and weak hip strength, mainly among female participants for abductors [46,51,52,53,54,55], external rotators [45,46,52,53] and extensors [46,52], but also in males for abductors [51,52,53] external rotators [45,52,53] and extensors [52,53]. However, some studies are of the opposite position, confirming the belief that evidence of the relationship between hip strength and DKV is conflicting [56,57]. The relationship between hip muscle strength and dynamic knee valgus undoubtedly depends on movement tasks that are used to assess valgus, i.e., ballistics, running, walking, cutting, squats, single-leg, double-legged. Different methods of assessing muscle strength also affect different results. Among other reasons, a systematic review of Cashman et al., examining the effect of weak hip muscles on DKV was unable to determine definitive conclusions or clinical recommendations [58]. Cronstrom et al., showed no relationship between hip strength (hip abduction, extension, external rotation) in women during various functional motor tasks [47]. A significant association (r = −0.38, 95% CI - 0.53 to –0.21, n = 114) was revealed between the lower hip external rotator strength and greater peak knee valgus angle in a subgroup of SLS test.
This problem was noticed by the team of researchers Dix et al., in their systematic reviews and meta-analysis, specifying the subgroups and revealing the link between hip muscle strength and knee valgus in ballistic SLL tasks, and to minor size SLS and not in ballistic double-leg tasks. The decreased strength of hip abductors, extensors and external rotators was associated with DKV during single-leg drop landings among subgroups of healthy women (p < 0.05). The difference in the results of the kinematic evaluation of the lower limbs between the test tasks of single-leg and double-legs is also due to different demands and muscle recruitments, which, among others, require greater eccentric work to provide control in the frontal plane angles [57]. During single-leg motor tasks, more eccentric work is required of the standing leg hip abductors to resist the contralateral pelvic depression and femoral adduction.
This thesis is confirmed by the latest study, which showed a strong negative correlation between knee abduction angle and concentric strength (r = −0.55. p = 0.02, R2 = 0.3) and also eccentric (r = −0.56. p = 0.01, R2 = 0.31) hip abductors in SLL tests among active women. In SLS in the same group there was a negative correlation between the knee valgus angle and hip abduction concentric strength (r = −0.55, p = 0.02, R2 = 0.3) and hip extension eccentric strength (r = −0.5, p = 0.04, R2 = 0.23) [53].
Activation and Coactivation of the Gluteus Muscles for Knee Control
Considering in more detail the muscle activation and strength, two muscles should be specified: Gluteus Medius (abductor) and Gluteus Maximus (extensor and external rotator). The approach by Naematallah et al., to the problem of the activation and strength of the hip concerning knee valgus is a relevant exploration of the topic. EMG activation was performed for men and women in various single-leg movement tasks (SLS and SLL in three directions). In the female group during SLL (Forward Landings) there was a correlation (r = 0.56, p = 0.01, R2 = 0.31) between gluteus maximus EMG activity and knee abduction angle. In the male group during SLS, gluteus medius EMG activity was strongly correlated (r = 0.65, p = 0.004) with the knee abduction angle [53]. However, the results show a positive correlation that suggests increased EMG activity along with increased valgus angles. This may indicate a heightened neural drive mechanism to increase muscle fiber recruitment in motion control for participants with lower hip strength [53,59].
Coactivation of muscles is an important mechanism in the stabilization and motor control of the lower limb. The condition of this phenomenon is the simultaneous contraction of agonists and antagonists of a given joint [60]. Evidence from Mauntel et al., allows us to bend the effect of gluteal muscle coactivation with hip adductors. Muscle coactivation ratios calculated by multiplying the average muscle activation of gluteus medius and maximus and the average activation of hip adductor (designated as GMax: Hip Add and GMed: HipAdd) were used in the study. During the descent phase of SLS the mean EMG amplitude was normalized to maximal voluntary isometric contraction (MVIC). Participants in the valgus group showed significantly (p < 0.05) smaller GMax: HipADD (2.4 ± 1.1), and GMed: HipADD (1.1 ± 0.62) ratios than the control group (4.5 ± 3.9 and 2.4 ± 1.8) Thus, EMG hip adductor activation was greater than EMG activation of the gluteus maximus and minimus in the valgus group compared to the control group [10].
In summary, there is some evidence to support the thesis about the influence of the strength of hip abductors, extensors and rotators in SLL tasks in women. In the SLS test, the relationship is conflicting. Coactivation of the gluteus muscles with hip adductors also seems to be important. For men, the evidence is less numerous and requires future research. However, it is worth considering adding to the prevention of lower limb injuries, and to training to improve the DKV pattern, and exercises strengthening the gluteal muscles for both women and men.
3.3. The Role of Strength and Muscle Activation Quadriceps and Hamstring in Stabilizing the Knee
The role of quadriceps and hamstrings in stabilizing the knee seems to be extremely important from an anatomical point of view. Both muscles are knee stabilizers, pressing the joint surfaces during movement. The hamstring and quadriceps muscles, thanks to their distal tibial attachments, counteract excessive rotational movements and abduction of the knee [61,62]. Several studies have revealed the relationship between knee flexor and knee extensor in valgus knee positioning in the SLS test [45,51,61] Claiborne et al., found a weak to moderate negative correlation knee flexion (r = –0.43, p < 0.001) and knee extension (r = –0.37, p < 0.05) showing that participants with greater knee strength exhibited less valgus motion. There is also evidence of the impact of concentric hamstring strength from a study in girls aged 10–13 (pubertal onset). The reduced concentric hamstring strength affected (p < 0.05) the reduced ability to control the lower limb, which increased knee valgus values during a jump and SLL [61]. In contrast, a weak positive correlation (r = 0.33, p = 0.02) marked in the research of Wilson et al., showed that the greater strength of the knee flexors, the greater the knee valgus angles [45]. A meta-analysis of the three above-mentioned studies (96 healthy participants in total) by Cronstrom et al., showed no evidence for the association of hamstring strength with a greater peak valgus moment (r = −0.20; 95% CI −0.54 to 0.19) [39]. There are hypotheses regarding support for knee joint stabilization in Varus-Valgus moments by quadriceps-hamstring muscle co-contraction. Co-contraction is used to stiffen a joint to control the position of the limb [62,63]. Probably, the mechanoreceptors lying in the periarticular structures, including the collateral ligaments of the knee, are responsible for the reflex tension of the lateral and medial muscles of the knee, thus counteracting valgus movements [63].
Increased pre-activity of the vastus lateralis muscle and decreased pre-activity of the vastus medialis predicts increased knee valgus in the jump and SLL in a female. Twenty-eight volunteers participated in a 3-D motion capture kinematic study assessing knee valgus during a jump and landing on one leg. In addition, participants had bipolar surface EMG electrodes synchronized with a motion capture system in order to assess the activity of the lower limb muscles (rectus femoris, vastus lateralis, vastus medialis, medial hamstring and lateral hamstring). The partial regression coefficients used (b) revealed an association between muscle activity and valgus in women. A greater knee valgus angle was associated with greater muscle pre-activity of the vastus lateralis (b = 1.397, p = 0.013) and lateral hamstring (b = 1.760. p = 0.008). A smaller valgus angle was associated with increased pre-activity of the vastus medialis muscle (b = 2.197, p = 0.009). There was no association between variables for both sexes together and for men separately (p ≥ 0.05) [64].
These studies support the hypothesis that muscular imbalance in medial-to-lateral quadriceps-hamstring co-contraction may contribute to increased knee valgus among recreationally active women [64]. Contrary to the above results, there is a study assessing knee valgus during SLL in thirty-five female athletes. EMG assessment of muscle pre-activity of the vastus lateralis (VL), rectus femoris, lateral hamstring (LH) and VL: LH ratio was not a significant predictive (p > 0.05) factor for knee abduction [65]. Despite the hypotheses and recent studies regarding knee muscles and DKV, the evidence is conflicting.
3.4. The Possible Impact of the Ankle Range of Motion and Foot Aspect
Considering the lower segment in the kinematic system of the lower limbs, it is impossible not to mention the role of the ankle and foot in the context of DKV.
Movement tasks consisting of squat or landing require, inter alia, flexion movement in the sagittal plane in the hip and knee joints and dorsiflexion in the ankle joint. If there is a range of motion (ROM) deficit in one segment of the lower limb system, there is usually compensation in the transverse and frontal planes. This situation can occur when the ROM of the ankle dorsal flexion is limited, which can force compensated movement of excessive pronation of the ankle, internal tibial rotation, adduction and internal rotation of the thigh and pelvic drop, which in turn leads to DKV [66,67,68]. Seven studies included in the meta-analysis of the researchers, Lima et al., allowed the publication of the claims, saying that the DF ROM restriction is associated with DKV (SMD −0.65, 95% CI −0.88 to –0.41), regardless of whether DF ROM was measured in a situation of foot loading (weight-bearing) or not (non-weight bearing), also with knee flexion or extension [68]. However, three studies in the meta-analysis were based on the lateral and forward step-down tasks [61,62,63], and only one study focused on the SLS test [12]. Evidence supporting the impact of the DF ROM restriction in the SLS test showed studies by Wyndow et al., and Mauntel et al. In both cross-sectional studies, 70 healthy subjects of both sexes participated [12,67]. In the study of Mauntel et al., DF ROM was examined with a goniometer in the 90° knee flexion and knee extension in a supine body position. The valgus group showed 37.5% (extended) and 33.1% (flexed) smaller DF ROM than the control group [12].
In the second study, the authors examined DF ROM in a wall test. The maximum distance of the foot (longest toe) from the wall that allows the knee to touch the wall without lifting the heel. The mean of DF ROM was (10.7 cm ± 3.4 cm), where the mean peak FPPA valgus (4° ± 7°). DF ROM was associated with valgus (Odds Ratio (OR) 1.8, 95% CI 1.2 to 2.9). A greater indicator of OR for ankle joint dorsiflexion indicates that a lower range of ankle contributes to a greater FPPA [67]. Moreover, participants with greater midfoot mobility are 2.4 more likely to achieve a greater peak valgus knee angle during SLS. Where mobility was measured as the difference in midfoot height in an unladen weight and the difference in midfoot width in the same way [67]. Pronation occurring as compensation at the moment of limiting the knee forward movement relative to the foot during squatting tasks occurs especially in midfoot and the subtalar joint [69]. Rear-foot eversion and excessive pronation can cause tibial internal rotation. This may result in a change in the kinematics and kinetics of the lower extremities during motor tasks [54,70]. In one study, one hundred and thirty female basketball players were tested for knee valgus by the 2-D method. The valgus was assessed as Knee-in distance (KID). It was the distance measured in centimeters from the big toe to the point where the line connecting the center of the patella with the anterior superior iliac spine falls to the ground. The heel-floor test (HFT) assessing rear-foot kinetics was positive when the eversion rear-foot angle reached ≥5˚ in SLS and SLL tests. Participants with a positive HFT showed higher valgus values than participants with a negative HFT in SLS (12.2 ± 5.1 cm, vs. 8.7 ± 5.2 cm) and in SLL (14.7 ± 7.2 cm vs. 8.9 ± 5.5 cm) [54]. The characteristics of studies in causes of dynamic knee valgus is presented Table 1.
There is evidence from two studies confirming the effect of the DF ROM restriction on DKV in SLS. More research comes from studies evaluating kinematics in the double-leg squat and lateral or forward step-down tests.
3.5. Fatigue as a Factor in the Context of Dynamic Knee Valgus
The problem of fatigue as a factor influencing the change in knee biomechanics has been studied for years [38,71,72]. Simplifying the definition, fatigue can be described as a reduction in the underlying physiological and psychological function, causing a change in movement and manifesting itself in altering movement patterns [7]. Fatigue can be divided into two mechanisms, central and peripheral. Central fatigue refers to reduced muscular activity, while peripheral fatigue refers to the reduced ability to generate strength. Both are characterized by a decrease in neuromuscular control properties [73]. Various fatigue protocols were used by researchers. Some researchers used exercises such as running on the treadmill, squats or jumps to provoke the central mechanism of fatigue [72,74,75]. When triggering a peripheral mechanism, researchers used resistance exercises directed at the local joint, e.g., flexion-extension in the knee joint [72]. Studies on the effects of fatigue on knee valgus among athletes show conflicting results. Santamaria et al., in their review showed the effect of fatigue protocols on increasing knee angle in SLL only when it was an unanticipated task [38], a systematic review of Barber-Westin et al., showed no difference in research on the effect of fatigue on knee kinematics (knee abduction and internal rotation) in single-leg tasks, both in planned and unplanned tasks (p > 0.05) [76] and finally, results that are not statistically significant on the overall fatigue effect on knee valgus in SLL in the latest comprehensive review (p > 0.05) [6]. The explanation for such results may be a non-standardized fatigue protocol and the provision of too low a load protocol for athletes.
The mechanisms of proprioception mentioned in the previous sections are responsible for the stabilization of the joints. Mechanoreceptors with distinction Golgi tendon organs and muscle spindles play an important role [19,77]. Muscle fatigue can reduce proprioceptive abilities anywhere along the pathway associated with muscle contraction [77]. Thus, fatigue by impairing the neuromuscular control of the lower limb may lead to impaired ability to dynamically stabilize the knee, including positioning the knee in the axis [77,78].
Neuromuscular fatigue is often mentioned as a modifiable risk factor for ACL injury. The hypotheses are related to the effect of fatigue on the altered pattern of muscle activation, reduction in muscle strength or increased ground reaction forces, [6,71,76,79]. In addition, fatigue pathways run parallel to injury pathways, which lead to a decreased performance by athletes, [71,80]. In contrast, Bourne et al. 2019, presented reviews showing no relationship between workload and the occurrence of ACL injury, highlighting deficiencies in quantifying fatigue parameters in prospective studies [81].
4. Exercise Training to Reduce Dynamic Knee Valgus
Exercises with the addition of real-time visual biofeedback can have a positive effect on the immediate reduction of DKV. Twenty-four women with observed MKD participated in the Marshall et al. 2020 study were assigned to the feedback group and control group. Kinematic evaluation of the lower limbs in the SLL test was performed using a 3-D analysis system. The intervention consisted of 1 session in which four exercises (SLS, double-leg squat, single-leg, and lateral step down) were performed by both groups in a mode of 10 repetitions each. Visual biofeedback in the feedback group consisted of performing exercises with an observation of its movement pattern on the monitor. The software responsible for the analysis of movement showed colors following the axis of the knee. The participant had to keep the color green, which appeared when the knee abduction angle was <5°. The feedback group decreased the knee abduction angle from preintervention (7.95° ± 3.80°) to postintervention (4.93° ± 1.64°) (p = 0.008) and decreased the angle by 6.16° more than in the control group in the landing phase IC [82].
The importance of the impact of the hip abductor muscle strength for DKV has been described in previous sections of this review. Palmer et al., attempted to evaluate five weeks of isolated hip abductor (side-lying hip abduction exercise with ankle weights) training in one group and functional motor exercises (from double-leg to single-leg squatting) in the second group in 29 healthy participants with observed knee valgus. A DKV reduction of 10° occurred in the group performing functional exercises and by 5° in the group strengthening the hip abductor in the SLS test. Despite clinically significant changes (clinically significant defined as a 3° reduction [77] in knee kinematics), the results were not statistically significant (p > 0.05) [83].
Also, in the Hopper study, despite the reduction of knee abduction in SLL (training group reduced DKV by 7.74° ± 7.42° compared to control group by 3.21° ± 5.66° at maximum knee flexion angle), the results were not statistically significant (p > 0.05). Of the twenty-three netball women, thirteen performed extensive neuromuscular training, and 10 were allocated in the control group without intervention. The six-week training consisted of several exercises divided into three stages (warm-up, plyometrics, strength) [84].
Statistically significant results for the reduction of valgus (p = 0.001) measured as FPPA in the SLS test were obtained by Dawson and Herrington's study. For six weeks, three times a week, gluteus medius and maximus training (side-lying hip abduction, quadruped leg extension, clam exercise and front step-up) were performed for the strength group and biofeedback training (SLS exercise with observation and correction of the technique in front of the mirror) for skill group. In both groups, there was a significant improvement in FPPA and remained at a similar level after 12 weeks from the value before training. DKV was reduced in the strength group from (12.76° ± 4.44°) to (7.28° ± 5.10°) and skill group (13.34° ± 4.46°) to (8.81° ± 4.22°). The biggest change occurred in women in the skill group with feedback training with an average of 8.1°. However, only 17 recreationally active participants took part in the study (strength group (four men, five women) and skill group (four men and four women)), which is a very small sample [85].
In addition, core-muscle training lasting eight weeks compared to the control group without intervention significantly influenced the reduction of the angular value of knee valgus in the SLS test in female basketball players. The valgus decreased from 5° (IQR = 2.0°–6.1°) to 2.2° (IQR = 0.9°–3.2°) (p = 0.008). No changes were observed in the control group. Core-muscle training performed on average 4.7 times a week consisted of three exercises (Nordic Hamstring, Side Plank, Front Plank) with individual intensity progression. It is worth noting that the same program did not change knee valgus angles in the double-legged DVJ test. This study also had a small sample size (n = 17) [86].
The combination of many types of exercises with an emphasis on the quality of movement control and the alignment of the limbs and torso, thus avoiding knee valgus contributes to the reduction of the risk of injury in sports populations [87,88]. The research team of Attwood et al. 2018, by introducing an Injury Prevention Exercise Program, which consisted of exercises to improve balance, proprioception, landing and cutting skills, and strengthening exercises showed a reduction in injuries among rugby players. Exercise progression focused, among other things, on changes in time, intensity, change of direction of movement, and by removing a visual component. Plyometric exercises changed consistently from simple double-legged tasks to demanding single-legged tasks. Feedback was used for participants in the form of information about the quality of movement and body alignment. The proposed program lasted 42 weeks, three times a week. The set consisted of a warm-up (5–10 min) and the main part (15 min) and was performed by 41 male adult rugby union clubs. Compared to the control group, the results showed a 40% reduced incidence of lower limb injuries. Including injuries of the knee ligaments, where the injury incidence rate in the control group was 1.24 (0.77–2.01), and in the intervention group was 0.61 (0.31–1.19) (90% CI) [87].
Exercises focused on muscle strengthening, balance and plyometric training, with lower limb positioning feedback (e.g., avoiding valgus) may be beneficial in reducing the risk of lower limb injuries.
DKV is a leading movement pattern that can be responsible for knee injuries to recreational and professional athletes. The above review focused on modifiable factors, with a look at particular segments in the kinematic chain and the role of fatigue in single-leg tasks. Evidence suggest that decreased mainly hip abductors, but also extensors, external rotators strength and higher midfoot mobility are potential factors predisposing to knee valgus during SLL. Strengthening and activating gluteal muscles, improving trunk lateral flexion strength, increasing ROM dorsiflexion ankle and midfoot mobility should be taken into account when planning training programs aimed at reducing DKV occurring in SLS. Evidence from one study suggests excessive rear-foot eversion as a cause of knee valgus in both SLS and SLL tests among young basketball players. There is some evidence from studies showing exercise training consisting of gluteal strengthening, biofeedback training, and a core-stability workout can improve the dynamic knee valgus pattern in healthy adults. It is worth considering the above reports in the context of selecting exercises for injury prevention programs.
A lower ratio of gluteal muscle co-activation to hip adductors and reduced mobility of the ankle and foot have been observed in people with DKV. Considering this evidence, it can be concluded that by reducing the tension or stretching of the hip adductors and plantar flexors of the ankle, we can reduce knee valgus angles.
Exercise programs to strengthen the muscles (with an emphasis on gluteal muscles), improve balance, core-stability and plyometric, with biofeedback on lower limb position, thereby avoiding knee valgus, provided by physicians, physical therapists and trainers, can reduce the angle of knee valgus and thus reduce the risk of lower limb injuries.
The vast majority of research into the causes of DKV is assessed in the female population. It should be noted that women show greater values of DKV than men. Although the double-leg tasks are the most common DKV assessment tests, lower limb injuries most often occur when landing on one leg. There is a significant difference in the shift of the center of gravity towards the opposite side from the SLL, which forces one side to engage more strongly. In the case of double-leg landing, the involvement is distributed bilaterally.
Therefore, research must focus more on the tasks of a single-leg rather than the double-legs. Further work is needed to determine causes for the occurrence of and exercise training for reducing DKV in single-leg tasks, especially in SLL.
Concept and design of the manuscript B.W, collection of literature B.W., D.Ś., original draft preparation B.W., K.Z.; project administration D.Ś.; review and editing B.W., D.Ś, K.Z.; editing and final approval K.Z.; All authors read and approved the final manuscript.
This research received no external funding.
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Figure 1. Example of dynamic knee valgus—knee move inwards from foot position (A) and correct movement pattern—knee under foot (B) during Single Leg Squat. Valgus quantitative assessment—angle between anterior superior iliac spine (ASIS), patella and center of malleolus (A)—145˚, (B)—180˚.
Table 1. Characteristics of studies in causes of dynamic knee valgus (DKV).
Study Participants Outcome parameters Results
Wilson et al. 2006 F = 22 (19.4 ± 0.7y)
M = 24 (19.9 ± 2.3y)
Division 1A or 1AA basketball,
soccer, or volleyball players. Peak isometric torque: trunk flexion, lateral flexion and extension
Knee valgus: FPPA (2-D) during SLS BOTH: SLS
Greater trunk lateral flexion strength among participant with lower knee valgus angles (FPPA)
Stickler et al. 2015 F = 40 (22.88 ± 0.32y) Handheld dynamometer isometric: side lying plank test (trunk lateral flexion)
Knee valgus: FPPA (2-D) during SLS FEMALE: SLS
Greater trunk lateral flexion strength among female with lower knee valgus angles (FPPA)
Nakagawa et al. 2015 F = 20
(both: 22.3 ± 3.0y)
Control group (healthy without PFP) Handheld dynamometer isometric: trunk extension, flexion with rotation and side bridge
Knee valgus: Electromagnetic tracking system (3-D) during SLS BOTH: SLS
Greater strength of trunk lateral flexion (side bridge test) among healthy participant with lower knee valgus angles.
soccer, or volleyball players. Peak isometric torque:
Knee flexion and extension
Greater strength of knee flexor among participant with higher knee valgus angles (positive correlation)
Claiborne et al. 2006 F = 15 (23.5 ± 3.7y)
M = 15 (26.4 ± 5.2y) Isokinetic eccentric/concentric strength:
knee extension and flexion
Knee valgus: FPKM (Frontal plane knee motion) in 3-D during SLS Both: SLS
Participants with greater knee strength exhibited less valgus motion
Wild et al. 2013 F = 33 (10–13y, Tanner stage II) Isokinetic eccentric/concentric strength:
Knee valgus: 3-D motion analyses system during SLL Female: SLL
Females with lower flexor (hamstring) strength displayed significantly greater knee valgus angles.
Palmieri-Smith et al. 2008 F = 18 (24.0 ± 5.2y)
recreationally
active (Tegner score 5 or 6). EMG:
Dynamic and MVIC
rectus femoris, vastus lateralis, vastus medialis, medial hamstring, lateral hamstring
Knee valgus: 3-D motion capture kinematic during SLL Female: SLL
A greater muscle pre-activity of vastus lateralis and lateral hamstring was associated with greater peak knee valgus angle. A smaller peak valgus angle was associated with increased pre-activity of the vastus medialis muscle
Both or males: SLL
Muscle activation was not associated with the peak knee valgus angle
Brown et al. 2013 F = 35 (15.1 ± 1.2y)
basketball, field hockey, and soccer players EMG:
vastus lateralis (VL), rectus femoris, lateral hamstring (LH)
Muscle pre-activity of vastus lateralis, rectus femoris, lateral hamstring, and VL: LH ratio was not a significant predictive.
Neamatallah 2020 F = 17 (25.7 ± 4.5y)
physically active (participating in least 3 h of exercise per week) Isokinetic muscle strength concentric/eccentric:
hip abduction and hip extension
Knee valgus: 3D motion analysis during SLS/SLL (Forward Landing - FL, Single Medial Landing -SML, Single Lateral Landing - SLL) FEMALE: SLS
Female with greater hip abduction concentric and hip extension eccentric strength had lower knee valgus angles
SLL (FL, SML, SLL)
Female with greater hip abduction concentric strength (very strong negative correlation) and hip abduction eccentric strength (strong negative correlation) had lower knee valgus angles.
Hip (abduction/adduction, flexion/extension, and
internal/external rotation
Greater strength of concentric hip abduction among participant with lower knee valgus angles.
(Weak to moderate negative correlation)
Suzuki 2015 F = 23 (19.96 ± 0.77y)
M = 20 (20.20 ± 1.54y)
intercollegiate basketball
players Hand-held dynamometer – hip extensor, abductor and external rotator
Knee valgus 3-D analysis system during SLL (SML) FEMALE: SLL
Greater knee valgus angle at IC among participant with lower strength of hip extension, hip abduction and external rotation.
Stickler et al. 2015 F = 40 (22.88 ± 0.32y) Handheld dynamometer isometric: hip abduction, extension, external rotation
Female with greater hip abduction, hip extension and external rotation strength had lower knee peak valgus angles (FPPA)
Hip abduction and external rotation
Greater hip external rotation strength among participant with greater knee valgus angles (positive correlation)
Jacobs & Matacola 2005 F = 10 (22.1 ± 2.3y)
M = 8 (24.1 ± 2.2y)
Recreationally active adults. Isokinetic peak eccentric torque:
Hip abductor
Knee valgus: 3-D analysis system during SLL FEMALE: SLL
Female with larger eccentric peak torque had lower peak knee valgus angles
MALE: SLL
No significant correlations between eccentric peak torque and knee valgus
ACTIVATION/COACTIVATION
Mauntel et al. 2013 MKD group (20.2 ± 1.8y)
F = 10
Control group (20.2 ± 1.5y)
physically active, defined as participation in at least 30 min. of physical activity, 3 times per week for at least 6 months EMG
Dynamic (descent phase of SLS) and MVIC
Gluteus maximus and medius, hip adductors (hip coactivation ratios)
Knee valgus: 3-D motion analysis during SLS
BOTH: SLS Hip coactivation ratios shows smaller gluteus medius to hip adductor (GMed:Hip Add) and gluteus maximus to hip adductor (GMax:Hip Add) coactivation ratios in valgus group than in the control group
physically active
(participating in least 3 h of exercise per week) EMG
Gluteus maximus and medius
Knee valgus: 3D motion analysis during SLS/SLL (Forward Landing, Single Medial Landing, Single Lateral Landing) FEMALE:
SLL (FL) Higher G Max EMG activity was associated with higher knee valgus angles among female (positive correlation).
SLS: Higher G Med. EMG activity was associated with higher knee valgus angles among male (positive correlation).
Wyndow et al. 2016 Both = 30 (22 ± 3y) Ankle dorsiflexion
knee-to-wall lunge test
Foot mobility was quantified as the difference in dorsal midfoot
height or midfoot width, between non-weight bearing and bilateral weight bearing positions
Knee valgus: 2-D FPPA during SLS BOTH: SLS higher midfoot width mobility, or lower ankle joint dorsiflexion range and midfoot height
mobility, were associated with a greater knee valgus angles (FPPA)
Mauntel et al. 2013 Valgus group (20.2 ± 1.8y)
physically active, defined as participation in at least 30 min. of physical activity, 3 times per week for at least 6 months Ankle dorsiflexion range
(in extended position)
Supine Leg straight – goniometer measurement
(in flexed)
Supine Knee flexed – goniometer measurement
Knee valgus: 3-D motion analysis during SLS BOTH: SLS
Valgus group displayed significantly less passive ankle dorsiflexion with the knee extended and flexed
Kagaya et al. 2015 F = 130 (16.9 ± 0.6y)
high-school basketball players, basketball experience, 6.7 ± 2.0 y. Rear-foot eversion alignment – dynamic heel-floor test (HFT)
Knee valgus: 2D video images (Knee-in distance) during SLS and SLL FEMALE: SLS and SLL
The KID were greater in the HFT-positive (≥5˚ angle)
than in the HFT-negative group (<5˚ angle)
Abbreviations: ACL—Anterior Cruciate Ligament, PFP—patellofemoral pain, SLS—Single Leg Squat, SLL—Single Leg Landings, BOTH—both sex (female and male), FPKM—Frontal Plane Knee Motion, FPPA—Frontal Plane Projection Angle, MKD—Medial Knee Displacement, EMG—Electromyography, MVIC—Maximum Voluntary Isometric Contraction, HFT—Heel-fFlot Test, KID—Knee-In Distance.
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text:
At the Career Track Assessor Awards
A young apprentice who has demonstrated outstanding commitment to her personal career development and made a significant contribution to the work of Colchester Borough Council, has been honoured with a 2020 Career Track Assessor Award.
Rima Miah, who has completed her apprenticeship in August 2019 and secured a permanent job as a Benefits Assistant with Colchester Borough Council, picked up her award from Cllr Dan Land, Chairman of Tendring District Council. The assessment of apprentices undertaking work-based training with Colchester Borough Council is overseen by Career Track (alongside other providers), which is operated by Tendring District Council.
The Career Track Assessor Award recognises the hard work and commitment of apprentices whose efforts impress their assessors and was independently judged by Career Track. In addition, Rima also received a certificate of achievement confirming the successful completion of her apprenticeship at the event. Jack Binnington, who works in Customer Solutions, also received a certificate of merit.
The award presentation took place during the 14th annual National Apprenticeship Week, which ran from 3 to 7 February and had 'Looking Beyond" as its theme.
To celebrate National Apprentice week, Colchester Borough Council also held its own event on the 5 February, at Colchester Town Hall, to showcase and provide insight into the apprenticeship programme and its success.
Councillor Mark Cory, Leader of Colchester Borough Council, said: "Apprenticeships play a vital role in giving young people from all backgrounds an opportunity to learn and develop the valuable workplace skills they need in today's highly competitive employment market.
"Congratulations to Rima, who is an inspirational ambassador for our Apprenticeship Scheme and whose hard work and outstanding commitment has marked her out for this special award."
Councillor David King, Colchester Borough Council's Portfolio Holder for Business and Resources, added: "All our apprentices work incredibly hard and are an enormous credit both to themselves and the customers they serve so well.
"I would like to congratulate and thank Rima and Jack for leading the way with our Apprenticeship Scheme and for helping to reflect the council's ongoing commitment to delivering excellent customer service and the quality of the service we provide to our residents."
3cf3885d-4402-4d6d-b81b-f4c4db22398a

redpajama_set_name: RedPajamaCommonCrawl


text:
Q: How do I enable recipient verification in Exchange? My problem basically boils down to this:
Exchange (2016) is accepting mail for non-existent addresses and then later sending out DSNs (delivery status notification) to notify the sender of failure. I want it to instead immediately reject mail sent to non-existent addresses with a 550 response.
More background
My setup looks roughly like this:
                                                 +-----+
                  Datacenter          Office     |User1|
+----------+      +---------+      +----------+  +-----+  +-----+
| Internet | <--> | Postfix | <--> | Exchange |           |UserN|
+----------+      +---------+      +----------+  +-----+  +-----+
                                                 |User2|
                                                 +-----+

Incoming mail hits my postfix server first, which does virus scanning, spam filtering and quarantine. It then gets forwarded on to our office Exchange server.
Postfix is configured to do recipient verification against the exchange server. This involves connecting to the server and performing a partial SMTP transaction, up to the RCPT TO command. If the server responds with code 250 then the recipient is considered valid.
The problem is that Exchange is always responding with 250... it apparently does not even attempt to do any validation upon receiving the RCPT TO command.
I have followed the instructions on technet for enabling the anti-spam functionality and recipient validation in Exchange, but I have no idea what it did, because the behavior of Exchange's SMTP server is exactly the same as it was before I did anything.
Here are the commands I have run on the Exchange server trying to get this working.
& $env:ExchangeInstallPath\Scripts\Install-AntiSpamAgents.ps1
Restart-Service MSExchangeTransport

Set-RecipientFilterConfig -Enabled $true
Set-RecipientFilterConfig -RecipientValidationEnabled $true

Is Exchange's recipient validation supposed to make it perform immediate validation upon receiving RCPT TO? (And if not, what exactly does it do?)

A: This question is similar, and its accepted answer worked for me.
For recipient validation to be done right after the RCPT TO command, you have to be connected to a Hub Transport (as opposed to a Frontend Transport). I edited an existing Hub Transport bound to port 2525, checking the box to allow "Anonymous users" to connect to it (make sure to lock this down by some other means, so only known servers can access it).
Then I changed the settings on my gateway (postfix) server to use port 2525 when communicating with this exchange server. At this point the recipient validation started working as intended.

A: I would switch to LDAP lookups instead of trying to do failures on the SMTP communication. A lot more reliable.

redpajama_set_name: RedPajamaStackExchange


A Clear Message was the theme of the Learning Centre end of term concert.
It was the highlight of the school term for the students of the Learning Centre when they hosted their annual concert last weekend.
Teacher Kristal Hutson told Barbados TODAY that they would usually spend the school term preparing the children for the event, slotting times in so they could rehearse.
"They would rehearse all term for the different talents and then we would allot them time to practise their pieces and as we got closer and closer to the concert they would practise more often and such," she said.
Regardless of their abilities, Hutson said the entire student body of about 84 children and young adults took part in the concert, in drama, dance, song, sign language, puppetry or any other skills they had.
Am looking to find a school for an 8 year old boy who probably has ADHD but is very intelligent, decidedly creative, actively inquisitive, and most affectionate. Parents do not have a lot of money so must find something affordable. Please advise if you (or anyone you know) offers this type of educational facility/programme.


Lihat profil Chong Jia Hui di LinkedIn, komuniti profesional yang terbesar di dunia. Chong telah menyenaraikan 5 pekerjaan pada profilnya. Lihat profil lengkap di LinkedIn dan terokai kenalan dan pekerjaan Chong di syarikat yang serupa.
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The UN's new focus on LGBT rights should be used to offer support to local activists and governments, not to perpetuate economic and social inequalities.
Two cargo ships collided south of Tokyo early Friday, and the coast guard was searching for six crew missing from the smaller vessel.
Kim Chong-hui ( b Yesan, Ch'ungch'ong Province, 1786; d Kwach'on, Kyonggi Province, 1856). Korean calligrapher, painter, scholar and poet.
View Chong Jia Hui's profile on LinkedIn, the world's largest professional community. Chong has 5 jobs listed on their profile. See the complete profile on LinkedIn and discover Chong's connections and jobs at similar companies.
Vessel details: JIA HUI SHAN. Discover the vessel's basic Details, including the vessel IMO / vessel MMSI and vessel Call Sign. Type: Bulk Carrier Vessel, Registered in Hong Kong. Find dead-weight-tonnage, Gross Tonnage and the Year of Build vessel details.
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Chew Kai He Dillon, SP. Chia Pei Qin, NYP. Chia Yi Qi, Nehemiah, NYP. Chloe Clarice Tan Jun Hui, NYP. Chong Jia Hui Desiree, NP. Chou Qi Ling Felicia, NP. Christopher Liew Wen Long, TP. Chua Jia Na, Sharra, NP. Chua Jun Kiat Alex, SP. Chua Ming Lim, RP. Chua Suen Lynn Mindez, NP. Chua Wee Sing Eric, NYP.
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What is the ship's current position? Where is the ship located? JIA HUI SHAN current position is N W on Apr 01, at 19:14 UTC. Vessel JIA HUI SHAN (IMO: , MMSI: ) is a bulk carrier built in and currently sailing under the flag of Hong Kong.


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Dez Bryant: Did you "Catch" his Rant on Twitter?
Dez Bryant and the Dallas Cowboys tumultuous football marriage ended after eight years of ups and downs. Bryant finished his tenure as a Cowboy with 531 catches, 7,459 yards, and 73 touchdowns. Despite never having a catch percentage over 70 percent, he was widely considered as one of the best receivers in the league from 2012-2014.
The problem for Bryant was that his last productive season was in 2014. That is why he finds himself on the outside looking in as a free agent.
dez just stating straight facts !
Most predictable offense in the league last year. What Dez is saying is straight facts, no creativity whatsoever!
But wait there is even a shot, from Bryant, at the Cowboys' owner Jerry Jones.
Bryant even felt slighted by teammate Sean Lee as well. He referred to him as a snake.
Don't worry though because Bryant wants us to know that he is not bitter, salty, or upset. Honestly.
Although Bryant might be keeping it real, it might be tough to overcome such an ordeal. He is on the outskirts of the NFL and was even linked to a potential signing with the Cleveland Browns. It will be hard to add him to a locker room that is already fragile to begin with. Bryant might have played his last down of football whether he likes it or not.
If he is done, keep it classy and "Throw up the X" Dez.


text:
Joaquin Andujar, former Cardinals ace, dies at 62
SportsMLB
Former St. Louis Cardinals ace Joaquin Andujar has died in his native Dominican Republic. He was 62. (The Associated Press)
PUBLISHED: September 8, 2015 at 5:26 pm | UPDATED: August 28, 2017 at 3:14 am
ST. LOUIS — Joaquin Andujar, a star pitcher with the St. Louis Cardinals in the 1980s, has died in his native Dominican Republic. He was 62.
The team said he died Tuesday. Leonardo Matos Berrido, president of the Dominican Baseball League, said the cause was diabetes complications.
The Cardinals planned a tribute to the fiery right-hander before playing the Cubs.
Andujar was a two-time All-Star during five seasons with the Cardinals from 1981-85. He had 20-win seasons in 1984 and '85 and led the National League in victories in '84 and was a member of the Cardinals World Series title team in 1982 and NL championship team in '85. Andjujar was ejected from Game 7 of the 1985 World Series.
Andujar also played for Houston and Oakland.


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Your trip... Your choice of destination! One lucky winner will receive $3500 in travel vouchers to the destination of their choice.
Tickets will also be for sale at the Iowa Dental Foundation Booth (booth 90) until 3:00 PM on Friday, May 3, 2019. The drawing will be made during the IDF and President's Cocktail Reception and Dinner, which begins at 6:30 PM on Friday, May 3, 2019. Need not be present to win.
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Detach the latch cable fastener (A) from the latch cable (B).
Disconnect the latch cable (A) from the lock knob (B).
Detach the inner handle cable fastener (A) from the inner handle cable (B).
Disconnect the inner handle cable (A) from the lock knob (B).
Pull the glass run channel (A) away as needed, and remove the bolt, then remove the center lower channel (B) by pulling it downward.
Remove the screws (A, B) securing the latch (C), then remove the latch through the hole in the door. Take care not to bend the outer handle rod (D), the cylinder cable (E) (driver's door), the latch cable (F), and the inner handle cable (G).
Driver's door: While pressing a middle flange portion (A) of the outer casing cover (B) against the latch, pull both outside flanges (C) of the retainer (D) upward.
Driver's door: Pull the middle flange portion (A) of the outer casing cover (B) up, then disconnect the cylinder cable (C) from the latch.
NOTE: As soon as the cable comes off the latch, the shutter (D) goes down into the connector (E).
Driver's door: If the retainer (A) of the lock cylinder cable (B) is damaged, release the hooks (C), then replace it.
Make sure the actuator connector is plugged in properly and each rod is connected securely.
Cylinder cable installation: Before installing the cylinder cable (A) to the latch, hang the elbow of the shutter (B) on the boss (C) as shown. Next install the cylinder cable fully into the connector (D), then push the retainer (E) until it snaps to engage the latch and the door cylinder securely. Make sure the elbow of the shutter is on the boss.
Remove the screw, then remove the latch protector (A) by releasing the hook (B).
Detach the latch cable (A) and the inner handle cable (B) from the latch (C).
Install the cable in the reverse order of removal.
Make sure the latch cable and inner handle cable are connected securely.


text:
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text:
Q: Polyline custom clickable markers centered I have this Google example code here, http://jsbin.com/EpujIcU/2/edit?js,output which is a polyline "route" with two normal markers along the route:

What I really would like is if I can tweak the marker, so it looks a lot nicer (small circle) - fx. like this picture:

The custom markers should still be clickable so I can put an info window to it.
I do know of the possibility of custom markers, but it doesn't place the marker in the middle of the line but instead in top (yes, my icon is badly draw):

Is it possible to get as I want in the middle picture?

A: Yes. You need to configure the anchor custom icon correctly.
icon: {url: "http://url/icon/png", anchor: new google.maps.Point(12,12)}


text:
Bulls Abroad: Cristian Casseres plays full 90 in Venezuela U-20 win over Bolivia
Cristian Casseres and the Venezuela men's U-20 team had a nice start to their November schedule.
Share All sharing options for: Bulls Abroad: Cristian Casseres plays full 90 in Venezuela U-20 win over Bolivia
Vincent Carchietta-USA TODAY Sports
New York Red Bulls fans likely won't see the best of Cristian Casseres until 2019 at least. The 18-year-old Venezuelan midfielder is assumed to be the answer to the question "what will the Red Bulls do when Tyler Adams leaves?". But his first team opportunities have been limited in 2018 - three appearances, one start, 97 minutes played for RBNY in MLS to date - and can reasonably be expected to remain limited until next season (or perhaps the season after that: he need not mimic Adams' rate of development; he's allowed to advance in his career at his own pace).
Until first team opportunities open up for him, Casseres' focus has been NYRB II. And he has a shot at appearing in next year's U-20 World Cup, but two things have to happen first: Venezuela has qualify for the tournament, and he has to be sure he's in the squad.
He is making progress toward the latter goal.
The Venezuela men's U-20 national team is using the November international break to test a squad of players against the caliber of opponent they will need to beat in order to qualify for the 2019 U-20 World Cup. Bolivia, Peru, and Ecuador have sent U-20 squads to Venezuela to play each other and La Vinotinto in a mini-tournament.
Este es el calendario de la #Vinotintosub20 para el Cuadrangular Internacional sub-20 a disputarse desde el próximo miércoles en el estadio Metropolitano de Cabudare, te esperamos!!!! #SomosDeTallaMundial #RumboAPolonia2019 #VamosVinotinto pic.twitter.com/4MniB5OtW8
— La Vinotinto (@SeleVinotinto) November 8, 2018
All four teams plus the rest of CONMEBOL (i.e. Argentina, Brazil, Colombia, Chile, Paraguay, and Uruguay) will meet at the 2019 South American U-20 Championship in January - and the top four teams at that tournament will qualify for the 2019 U-20 World Cup.
There isn't a lot of time left for a squad to be selected for January; final decisions will have to be made soon about the roster chosen to try to win World Cup qualification. So it is encouraging news for Casseres that he was selected to the Venezuela U-20 squad for this November tournament.
And it is perhaps more encouraging that he started La Vinotinto's opening game of the competition against Bolivia. Per the VinotintoSub20 Facebook page, Casseres played the full 90 minutes, picking up a yellow card in a game Venezuela won, 1-0.
Reports suggest La Vinotinto perhaps ought to have won more convincingly, so the style of the performance was maybe more satisfying than the scoreline.
Venezuela is back in action on Friday, November 16, against Ecuador.


text:
Q: Postgresql 9.4 clusters not auto starting on Debian I have Debian 8.2 x64 and Postgresql 9.4 (from repo). I've recreated default cluster in different location like this:
# service postgresql stop
# pg_dropcluster 9.4 main
# pg_createcluster -d /srv/postgresql/data/9.4/main 9.4 main -- -W -A md5
# service postgresql start

and then I can connect to the database with:
# psql -WU postgres

then I've created another cluster with:
# pg_createcluster -d /srv/postgresql/data/9.4/apps -p 5433 9.4 apps -- -W -A md5

I can start it with:
# pg_ctlcluster 9.4 apps start

and connect:
# psql -WU postgres -p 5433

but the init script starts only the main cluster ignoring apps and acording to the man pages if /etc/postgresql/9.4/apps/start.conf doesn't exists it is assumed to auto start cluster. But this is my /etc/postgresql/9.4/apps/start.conf
# Automatic startup configuration
# auto: automatically start/stop the cluster in the init script
# manual: do not start/stop in init scripts, but allow manual startup with
#         pg_ctlcluster
# disabled: do not allow manual startup with pg_ctlcluster (this can be easily
#           circumvented and is only meant to be a small protection for
#           accidents).

auto

so it should also start apps cluster or did I misunderstand something or there should be some other options set ?
UPDATE
Well I think I've fixed my problem with:
# apt-get install --reinstall postgresql-common

and after this all clusters are controlled by the init script, and:
# service postgresql start|stop|restart

or
systemctl start postgresql.service

affect all clusters. It's weird cause first installation and reinstallation didn't report any errors.


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Like the works that run a pool or spa, there is a basic set of equipment for safety and water rescue. At a minimum, you should keep a life (or toss) ring, shepherd's hook, and rescue tube in good repair and within a few steps of the water. For longer and larger pools, double the set and keep each one at opposite ends of the pool.
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