The Feasibility of Using the Virtual Time-to-Contact Measure of Postural Stability to Examine Postural Recovery in People With Diabetes Mellitus

This study aimed to examine the feasibility of using time-to-contact measures during the perturbation protocol in people with diabetes mellitus. Three-dimension motion capture and force data were collected during 0.5-s perturbations in four directions (forward, backward, right, and left) and at two accelerations (20 and 40 cm/s2) to compute the time-to-contact. Time-to-contact analysis was divided into three phases: perturbation, initial recovery, and final recovery. The statistical analysis showed the main effects of Direction and Phase (p < .01) as well as a Direction by Phase interaction (p < .01). Backward perturbation with lower acceleration and backward/forward perturbation with higher acceleration had deleterious effects on postural stability in people with diabetes mellitus.

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Residual deficits from concussion as revealed by virtual time-to-contact measures of postural stability

Clinical Neurophysiology ◽

10.1016/j.clinph.2007.10.006 ◽

2008 ◽

Vol 119 (2) ◽

pp. 281-289 ◽

Cited By ~ 66

Author(s):

Semyon Slobounov ◽

Cheng Cao ◽

Wayne Sebastianelli ◽

Elena Slobounov ◽

Karl Newell

Keyword(s):

Postural Stability ◽

Time To Contact ◽

Virtual Time

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Virtual time-to-contact of postural stability boundaries as a function of support surface compliance

Experimental Brain Research ◽

10.1007/s00221-006-0703-4 ◽

2006 ◽

Vol 177 (4) ◽

pp. 471-482 ◽

Cited By ~ 30

Author(s):

Pamela S. Haibach ◽

Semyon M. Slobounov ◽

Elena S. Slobounova ◽

Karl M. Newell

Keyword(s):

Postural Stability ◽

Support Surface ◽

Stability Boundaries ◽

Time To Contact ◽

Virtual Time

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Compromised Dynamic Postural Stability Under Increased Load Carriage Magnitudes

Journal of Applied Biomechanics ◽

10.1123/jab.2018-0473 ◽

2020 ◽

Vol 36 (1) ◽

pp. 27-32

Author(s):

Alice D. LaGoy ◽

Caleb Johnson ◽

Katelyn F. Allison ◽

Shawn D. Flanagan ◽

Mita T. Lovalekar ◽

...

Keyword(s):

Body Weight ◽

Postural Stability ◽

Reaction Force ◽

Stability Index ◽

Load Carriage ◽

Men And Women ◽

Similar Performance ◽

The Impact ◽

Dynamic Postural Stability ◽

Force Data

Warfighter performance may be compromised through the impact of load carriage on dynamic postural stability. Men and women may experience this impact to differing extents due to postural stability differences. Therefore, the authors investigated the effect of load magnitude on dynamic postural stability in men and women during a landing and stabilization task. Dynamic postural stability of 32 subjects (16 women) was assessed during the unilateral landing of submaximal jumps under 3 load conditions: +0%, +20%, and +30% body weight. Dynamic postural stability was measured using the dynamic postural stability index, which is calculated from ground reaction force data sampled at 1200 Hz. Two-way mixed-measures analysis of variance compared dynamic postural stability index scores between sexes and loads. Dynamic postural stability index scores were significantly affected by load (P = .001) but not by sex or by the sex by load interaction (P > .05). Dynamic postural stability index scores increased between the 0% (0.359 ± 0.041), 20% (0.396 ± 0.034), and 30% (0.420 ± 0.028) body weight conditions. Increased load negatively affects dynamic postural stability with similar performance decrements displayed by men and women. Men and women warfighters may experience similar performance decrements under load carriage conditions of similar relative magnitudes.

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The effects of isometric exercises and stretching on postural stability in Non–Insulin Dependent Diabetes Mellitus patients with diffuse symmetrical sensory motor neuropathy

South African Journal of Physiotherapy ◽

10.4102/sajp.v65i2.84 ◽

2009 ◽

Vol 65 (2) ◽

Author(s):

S. Nenkova ◽

A. Stewart ◽

J. Potterton ◽

P. Becker

Keyword(s):

Diabetes Mellitus ◽

Postural Stability ◽

Insulin Dependent Diabetes Mellitus ◽

Dependent Diabetes Mellitus ◽

Control Group ◽

Motor Neuropathy ◽

Sensory Motor ◽

Insulin Dependent ◽

Experimental Group ◽

Niddm Patients

The purpose of this study was to explore the effects of isometric exercises and stretching on postural stability in Non – Insulin Dependent Diabetes Mellitus (NIDDM) patients with diffuse symmetrical sensory motor neuropathy. Patients were assigned to an experimental group and amatched control group. The experimental group received isometric exer-cises and stretching three times weekly for 12 weeks in addition to routine medication and dietary advice. A t the end of this period, this group wascompared with the control group, which received routine medication anddietary advice only. Measurements of muscle strength of quadriceps, ham-strings, ankle plantar and dorsiﬂexors, and Romberg’s test for postural sta-bility were carried out before and after the 12 weeks intervention. The study showed that isometric exercises and stretching for the lower extremities improved postural stability (p = 0.00)and strength of the quadriceps (p = 0.001) hamstrings (p = 0.001) dorsiﬂexors (p = 0.001) plantarﬂexors (p = 0.001)in NIDDM patients with diffuse symmetrical sensory motor neuropathy. This exercise regimen also had a loweringeffect on blood glucose level (p = 0.00). In conclusion it seems that the simple exercise intervention described in thisstudy may be of beneﬁt to these patients if incorporated into their management programmes.

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Effectiveness of various materials in reducing plantar shear forces. A pilot study

Journal of the American Podiatric Medical Association ◽

10.7547/87507315-90-7-346 ◽

2000 ◽

Vol 90 (7) ◽

pp. 346-353 ◽

Cited By ~ 13

Author(s):

M Curryer ◽

ED Lemaire

Keyword(s):

Diabetes Mellitus ◽

Pilot Study ◽

Diabetic Foot ◽

Shear Force ◽

Foot Ulcers ◽

Shear Forces ◽

Patients With Diabetes ◽

Force Data ◽

Precipitating Factor ◽

Better Than

Vertical plantar forces are known to be a major precipitating factor in the development of foot pathology. It is also postulated that shear forces are important in the pathogenesis of foot ulcers in patients with diabetes mellitus. Various materials are used in insoles designed to reduce forces on the foot. While many foam materials have been tested for their ability to dissipate vertical forces, few studies have tested the effect of these materials on shear forces. This study assessed the effectiveness of five different materials in reducing plantar shear forces and compared two new gel materials with three of the more conventional foam materials. Four subjects were tested while walking over a force platform with one of the five materials taped to the surface. Peak force, impulse, and resultant shear force data were analyzed. The gel materials were significantly better than the foam materials at reducing shear forces. Thus the use of gel materials in insoles may be indicated for the reduction of plantar shear forces on the diabetic foot.

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Virtual time-to-contact identifies balance deficits better than traditional metrics in people with multiple sclerosis

Experimental Brain Research ◽

10.1007/s00221-019-05698-6 ◽

2019 ◽

Vol 238 (1) ◽

pp. 93-99 ◽

Cited By ~ 1

Author(s):

Tyler T. Whittier ◽

Sutton B. Richmond ◽

Andrew S. Monaghan ◽

Brett W. Fling

Keyword(s):

Multiple Sclerosis ◽

Time To Contact ◽

Balance Deficits ◽

Virtual Time ◽

Better Than

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The Influence of Peripheral Neuropathy, Gender, and Obesity on the Postural Stability of Patients with Type 2 Diabetes Mellitus

Journal of Diabetes Research ◽

10.1155/2014/787202 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Aline Herrera-Rangel ◽

Catalina Aranda-Moreno ◽

Teresa Mantilla-Ochoa ◽

Lylia Zainos-Saucedo ◽

Kathrine Jáuregui-Renaud

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Peripheral Neuropathy ◽

Postural Stability ◽

Static Posturography ◽

Gender And Age ◽

Soft Surface ◽

History Of

Aim.To assess the influence of peripheral neuropathy, gender, and obesity on the postural stability of patients with type 2 diabetes mellitus.Methods.151 patients with no history of otology, neurology, or orthopaedic or balance disorders accepted to participate in the study. After a clinical interview and neuropathy assessment, postural stability was evaluated by static posturography (eyes open/closed on hard/soft surface) and the “Up & Go” test.Results.During static posturography, on hard surface, the length of sway was related to peripheral neuropathy, gender, age, and obesity; on soft surface, the length of sway was related to peripheral neuropathy, gender, and age, the influence of neuropathy was larger in males than in females, and closing the eyes increased further the difference between genders. The mean time to perform the “Up & Go” test was 11.6 ± 2.2 sec, with influence of peripheral neuropathy, gender, and age.Conclusion.In order to preserve the control of static upright posture during conditions with deficient sensory input, male patients with type 2 diabetes mellitus with no history of balance disorders may be more vulnerable than females, and obesity may decrease the static postural control in both males and females.

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Evaluation of Time-to-Contact Measures for Assessing Postural Stability

Journal of Applied Biomechanics ◽

10.1123/jab.22.2.155 ◽

2006 ◽

Vol 22 (2) ◽

pp. 155-161 ◽

Cited By ~ 45

Author(s):

Jeffrey M. Haddad ◽

Jeff L. Gagnon ◽

Christopher J. Hasson ◽

Richard E.A. Van Emmerik ◽

Joseph Hamill

Keyword(s):

Control System ◽

Postural Stability ◽

Center Of Pressure ◽

Center Of Mass ◽

Stability Boundary ◽

Quiet Stance ◽

Postural Control System ◽

Time To Contact ◽

Additional Information ◽

Spatial Measures

Postural stability has traditionally been examined through spatial measures of the center of mass (CoM) or center of pressure (CoP), where larger amounts of CoM or CoP movements are considered signs of postural instability. However, for stabilization, the postural control system may utilize additional information about the CoM or CoP such as velocity, acceleration, and the temporal margin to a stability boundary. Postural time-to-contact (TtC) is a variable that can take into account this additional information about the CoM or CoP. Postural TtC is the time it would take the CoM or CoP, given its instantaneous trajectory, to contact a stability boundary. This is essentially the time the system has to reverse any perturbation before stance is threatened. Although this measure shows promise in assessing postural stability, the TtC values derived between studies are highly ambiguous due to major differences in how they are calculated. In this study, various methodologies used to assess postural TtC were compared during quiet stance and induced-sway conditions. The effects of the different methodologies on TtC values will be assessed, and issues regarding the interpretation of TtC data will also be discussed.

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