Level Of Postural Stability Research Articles

Quadriceps Strength, Postural Stability, and Pain Mediation in Bilateral Knee Osteoarthritis: A Comparative Analysis with Healthy Controls.

Bilateral knee osteoarthritis (OA) poses significant challenges to individuals' functional abilities, including quadriceps strength, postural stability, and pain perception. Understanding the complex relationships among these factors is crucial for enhancing knee OA management strategies. The primary objective of this research is to evaluate and draw comparisons between the strength of the quadriceps and the level of postural stability in two distinct groups: individuals afflicted with bilateral knee OA and those who are healthy. Furthermore, the study seeks to examine the potential correlation between the strength of the quadriceps and the level of postural stability in individuals with knee OA. In addition to this, an investigation into the potential mediating effect of pain on the relationship between these physiological factors will also be conducted. A total of 95 participants with bilateral knee OA and 95 healthy controls were recruited. Quadriceps strength was assessed using dynamometry and postural stability was evaluated through anterior-posterior and medial-lateral sway measurements along with the ellipse area using a force plate. Pain levels were measured using the Visual Analog Scale (VAS). Mediation analysis was employed to explore the role of pain in mediating the relationship between quadriceps strength and postural stability. Statistical analyses included t-tests, Pearson correlation coefficients, and mediation analysis. Knee OA participants exhibited significantly lower quadriceps strength (1.08 Nm/kg ± 0.54) compared to controls (1.54 Nm/kg ± 0.57, p < 0.001). They also demonstrated compromised postural stability with increased anterior-posterior sway (9.86 mm ± 3.017 vs. 2.98 mm ± 1.12, p < 0.001), medial-lateral sway (7.87 mm ± 2.23 vs. 3.12 mm ± 1.34, p < 0.001), and larger ellipse area (935.75 mm2 ± 172.56 vs. 436.19 mm2 ± 135.48, p < 0.001). Negative correlations were observed between quadriceps strength and postural stability variables (r = from -0.43 to -0.51, p < 0.001). Pain significantly mediated the relationship between quadriceps strength and postural stability variables (p < 0.05). This study highlights the associations between quadriceps strength, postural stability, and pain mediation in individuals with bilateral knee OA. Our findings emphasize the need for targeted interventions addressing quadriceps weakness and compromised postural stability. Additionally, the mediation effect of pain underscores the complexity of these relationships, offering insights for more effective management strategies.

Assessment of postural stability using the Zebris Platform in women above the age of 60

Introduction. Balance control and body posture stability disorders progressing with age are caused by the involutionary changes in the function of the motor and nervous systems. However, it is indicated that regular physical activity, also in older adulthood, may have a positive effect on maintaining the functions of individual systems at an optimal level. Study aim: The aim of the study was to assess the postural stability of women above the age of 60 who declare active lifestyles. Material and Methods. The research involved 24 women, who were arbitrarily divided into 3 groups according to their calendar age. The younger group consisted of 14 women below the age of 70 years ( x _ = 65.08; SD = 2.82), whereas the older group comprised 10 older adults, above the age of 70 ( x _ = 73.62; SD = 2.74). The scope of the study included evaluation of selected postural stability parameters: 95% of the ellipse area covered by the moving COP, statokinesiogram path length, mean speed regarding displacement of the centre of foot pressure, total left and total right foot pressure. The examinations were performed in June 2018 using the Zerbis FDM-S dynamographic platform. The research material collected in this way was subjected to statistical analysis. Basic descriptive statistics were calculated and normality of the distribution of variables was verified using the Shapiro- Wilk test. The Student’s t-test for independent variables or Mann-Whitney’s U-test (depending on the distribution) were used to determine the significance of differences concerning the analysed parameters of postural stability between the groups studied. Furthermore, for 95% of the ellipse area covered by the moving COP, statokinesiogram path and mean speed of the displacement of the centre of foot pressure and standardised profiles were calculated for both chronological age groups. Standardisation of the results was performed using means and standard deviations of the entire material (T scale). Results. The results of the study indicate a higher level of postural stability among women from the younger group. However, comparative analysis did not reveal any statistically significant intergroup differences. Mean point scores on the T scale in the group of younger women for the 3 variables ranged from 50.98 to 51.60 points, whereas for older women, this was from 48.90 to 48.98 points. The differences between characteristics in the group of younger women totalled ca. 0.62 points, while in the older group, this value was 0.08 points. Conclusions. comparative analysis allowed to show that postural stability indices in women above 70 decreased compared to the results obtained for the younger group. Regular physical activity may be one of the significant factors in the prevention of postural stability regression.

Gender differences in postural stability in elderly people under institutional care.

The aim of the research was to assess the postural stability indicators of older women and men receiving i nstitutional care. The study involved 123 people aged 65-85, living in residential care homes in Rzeszów district. The main research tool was the CQ-Stab 2P 2-platform posturograph. There were statistically significant differences between women and men in the total statokinesiogram path length, the statokinesiogram path length in the anteroposterior direction, the mean COP displacement in the anteroposterior direction as well as the mean velocity of the COP point in the anteroposterior direction under eye control (p = 0.04). In the case of absence of visual control, men were characterized by significantly worse parameters in the area of mean COP displacement in the anteroposterior and lateral directions as well as the maximal COP displacement in the anteroposterior and lateral directions. It indicated that without visual control, body balance parameters in men significantly worsened along with increasing age. A statistically significant difference was found between both genders in terms of the statokinesiogram path length, the mean COP displacement and the mean COP velocity (p < 0.05). Gender differences in postural stability of older people under institutional care were noticed. Men were characterized by a lower level of postural stability compared to women. Elimination of visual control significantly worsened the balance of the body. The results obtained indicate the necessity of introducing therapeutic programs in nursing homes, taking proprioceptive exercises and exercises without visual input into account.

The Relationship between Postural Stability and Lower-Limb Muscle Activity Using an Entropy-Based Similarity Index.

The aim of this study is to see if the centre of pressure (COP) measurements on the postural stability can be used to represent the electromyography (EMG) measurement on the activity data of lower limb muscles. If so, the cost-effective COP data measurements can be used to indicate the level of postural stability and lower limb muscle activity. The Hilbert–Huang Transform method was used to analyse the data from the experimental designed to examine the correlation between lower-limb muscles and postural stability. We randomly selected 24 university students to participate in eight scenarios and simultaneously measured their COP and EMG signals during the experiments. The Empirical Mode Decomposition was used to identify the intrinsic-mode functions (IMF) that can distinguish between the COP and EMG at different states. Subsequently, similarity indices and synchronization analyses were used to calculate the correlation between the lower-limb muscle strength and the postural stability. The IMF5 of the COP signals and the IMF6 of the EMG signals were not significantly different and the average frequency was 0.8 Hz, with a range of 0–2 Hz. When the postural stability was poor, the COP and EMG had a high synchronization with index values within the range of 0.010–0.015. With good postural stability, the synchronization indices were between 0.006 and 0.080 and both exhibited low synchronization. The COP signals and the low frequency EMG signals were highly correlated. In conclusion, we demonstrated that the COP may provide enough information on postural stability without the EMG data.

Influence of a nine-day alpine ski training programme on the postural stability of people with different levels of skills

Summary Study aim: In alpine skiing, balance is one of the key elements that determine the effectiveness of the ride. Because of ski boots, the foot and ankle joint complex is excluded from the process of maintaining the stability of the body. The aim of the study was to determine to what extent a few days of skiing activities and the level of technical skills affect the skiers’ level of postural stability. Material and methods: The study involved 10 beginner (20.7 ± 1.1 years, 76.4 ± 8.7 kg, 184.4 ± 6.1 cm) and 10 advanced (20.5 ± 0.5 years, 80.5 ± 13.7 kg, 184.5 ± 9.5 cm) skiers, who participated in a nine-day ski training camp. Measurements of the postural stability were taken on the first and last days of the camp, on an AccuSway (AMTI, USA) stabilometric platform. Results: In both groups, a significant (p &lt; 0.05) improvement in stability was observed after the training camp only while standing in ski boots. While standing on two feet, the participants were more stable barefoot (p &lt; 0.05), and when standing on one foot they were more stable in the ski boot trial (p &lt; 0.05). Conclusions: Skiing had a positive effect on the postural stability only in measurement conditions that were similar to those in which this stability was practiced, i.e. in measurements involving ski boots. The restriction of mobility within the ankle joint significantly influenced the training-induced changes in the postural stability of both beginner and advanced alpine skiers.

The Effect of Sensorimotor Training on the Postural Stability of Visually Impaired Women Over 50 Years of Age

Previous studies indicated that blind and visually impaired people are a group with greater risk of falls. Postmenopausal changes significantly decrease physical efficiency and impair the body’s mechanisms for maintaining postural stability. In addition, the frequency of falls among women is much higher than in men. The aim of this study was to analyze the effect of sensorimotor exercise on changes in postural stability of visually impaired women over 50 years of age. Visually impaired women from group E showed a lower level of postural stability measured with EO compared to the healthy women. After completing the exercise, a more pronounced improvement in the level of postural stability was observed in group E.

Body Posture Stability in Ski Boots Under Conditions of Unstable Supporting Surface

The authors attempted to determine whether: (1) there are differences in stability between the conditions of standing in ski boots and barefoot, (2) the type of surface affects stability, and, (3) the level of stability differs between the frontal and sagittal planes. The study included 35 young male recreational skiers aged 20.71 ±0.63 years. Measurements of stability were taken by means of a Libra seesaw balance board. The conditions of soft surface were created by attaching an inflated cushion to the board. The experiment was carried out on both rigid and soft surface for both movement planes and two different conditions: maintaining the seesaw balance board in the horizontal position and performance of a particular balancing task. All the tests were performed with visual feedback. Restricted ankle joint mobility that results from wearing ski boots caused a reduction of stability in studied subjects, particularly in the sagittal plane. The differences found in the study were likely to be caused by the difficulty the beginners experienced in re-organizing muscular coordination in hip joint strategy and effectively using mechanical support of ski boots that reduces lower limb muscle tone. The use of the soft surface improved stability exhibited by the subjects in the frontal plane without compromising the stability in the sagittal plane. The soft surface might have contributed to a reduction in excessive corrective movements, thus improving stability in studied subjects. The aim of this study was to determine the effect of limitation of foot mobility and disturbances in afferent information from the plantar mechanoreceptors due to wearing ski boots on the level of postural stability in beginner skiers under conditions of the unstable support surface.

O efeito do esforço na estabilidade postural em jovens jogadores de futebol

OBJECTIVE: Analyze the effects of physical exertion during a soccer match on the functional capacity and stability of the lower limbs of young soccer players. METHODS: We analyzed 10 soccer players who underwent functional capacity assessment of the lower limbs by a Hop Test protocol and evaluation of the level of postural stability in the Biodex Stability System (Biodex, Inc., Shirley, NY) before and immediately after a friendly game lasting 45 minutes. RESULTS: After the match, there was a decrease in overall stability index (F(1,23) = 7.29 P = .024) and anterior posterior index (APSI) (F(1,23) = 5.53 P = .043). Fatigue in the dominant limb was responsible for the significant deficit in OSI (F(1,23) = 3.16, P = .047) and APSI (F(1,23) = 3:49, P = .029), while the non-dominant limb did not cause any change in the pre and post-game. CONCLUSION: A football match can cause decreased stability and functional capacity of the lower limbs in young players. Level of Evidence III, Pre-test and Post-test Study (Case-control).

Postural stability during static strain before and after a submaximal aerobic bicycle test in athletes

The aim of study was to investigate static balance control in wrestlers (n = 31) and effects of fatigue on postural regulation in two position: bipedal stance and squat position with open eyes prior to and 2 min after bicycle PWC(170) test. A force platform ("Ritm". Russia) was used to determine static balance control. We found a minimum difference in postural control between wrestlers and controls prior to exercise in bipedal stance. In squat position linear and angular (all p < 0.001) sway velocity of centre of pressure were lower in wrestlers and were negatively correlated to PWC(170) index (r = 0.454 and r = 455, p < 0.001 with linear and angular sway velocities respectively) indicating that 20% dispersion of sway velocities in static strain position may be determined to physical working capacity. After PWC(170) test all parameters of sway were increased in both groups both in bipedal stance (p < 0.01) and squat position (p < 0.001) indicating an important role of muscular fatigue in the decrease of postural stability in both groups. Linear velocity after PWC(170) in bipedal stance increased to an equal extent in both groups but the increases of velocities of sway of centre of pressure in squat position were lower in athletes (ANOVA, p = 0.037 for linear and p = 0.008 for angular sway velocities respectively) and were negatively correlated to an extent of recovery of heart rate after PWC(170) indicating some contribution (6.5-14.2% of dispersion of linear and angular sway velocities) of an recovery rate to maintenance of a high level of postural stability in an static strain position in wrestlers during physical fatigue.

The effects of one-half of a soccer match on the postural stability and functional capacity of the lower limbs in young soccer players

OBJECTIVE:Most injuries occur during the final 15 minutes of each half of a soccer match, suggesting that physical exertion may influence changes in neuromuscular control and the body's ability to stabilize the joints of the lower extremities. The aim of this study was to analyze the effects of one-half of a soccer match on the functional capacity and stability of the lower limbs in young soccer players.METHODS:We analyzed 27 soccer players by evaluating the functional capacity of their lower limbs using the hop test protocol and their level of postural stability using the Biodex Stability System. The evaluations were performed before and after 45 minutes of game time.RESULTS:After the match, there was a decrease in the overall stability index (OSI) (F(1,23) = 5.64, p = 0.026) and the anterior-posterior stability index (APSI) (F(1,23) = 5.24,p = 0.032). In the single and triple hop tests, there was a higher functional capacity in the dominant limb compared to the non-dominant limb in the pre- and post-game comparisons.CONCLUSION:The results of this study show that there is a decrease in the stability of the lower limbs in young soccer players after a 45 minutes soccer match, but the same result was not found for the functional capacity.