Stair Walking Research Articles

靴型足圧計測装置を用いた階段昇降と坂道歩行時の足底荷重解析

靴型足圧計測装置を用いた階段昇降と坂道歩行時の足底荷重解析

Effects of low light on the stability of the head and pelvis of the healthy elderly.

[Purpose] The purpose of this study was to evaluate the changes in body stability of the elderly while walking on even surface ground under low light. [Subjects] Ten young males and ten elderly males participated in this experiment. [Methods] Each subject walked along a 7 m walkway five times at their preferred walking speed under normal (>300 lux, NORM) and low light conditions (<5 lux, LOW). To compare the changes in body stability, the root mean square of acceleration (RMSacc) at the head and pelvis was used. [Results] The results show that the body stability of young adults showed a similar RMSacc in all directions at the head and pelvis between the normal and low light walking conditions. In contrast, the RMSacc in all directions at the head and pelvis during low light walking by elderly adults was significantly greater than that of normal light walking. [Conclusion] It was confirmed that, despite walking on even ground, low light condition affects the body stability of the elderly. To clearly evaluate the effect of low light with aging on gait pattern, further study will be necessary to perform additional experiments under various environmental conditions to investigate walking speed, multi-tasking, stairs, and uneven walkway performance.

On the relationship between tibia torsional deformation and regional muscle contractions in habitual human exercises in vivo

The mechanical relationship between bone and muscle has been long recognized. However, it still remains unclear how muscles exactly load on bone. In this study, utilizing an optical segment tracking technique, the in vivo tibia loading regimes in terms of tibia segment deformation in humans were investigated during walking, forefoot and rear foot stair ascent and running and isometric plantar flexion. Results suggested that the proximal tibia primarily bends to the posterior aspect and twists to the external aspect with respect to the distal tibia. During walking, peak posterior bending and peak torsion occurred in the first half (22%) and second half (76%) of the stance phase, respectively. During stair ascent, two noticeable peaks of torsion were found with forefoot strike (38% and 82% of stance phase), but only one peak of torsion was found with rear foot strike (78% of stance phase). The torsional deformation angle during both stair ascent and running was larger with forefoot strike than rear foot strike. During isometric plantar flexion, the tibia deformation regimes were characterized more by torsion (maximum 1.35°) than bending (maximum 0.52°). To conclude, bending and torsion predominated the tibia loading regimes during the investigated activities. Tibia torsional deformation is closely related to calf muscle contractions, which further confirm the notion of the muscle–bone mechanical link and shift the focus from loading magnitude to loading regimes in bone mechanobiology. It thus is speculated that torsion is another, yet under-rated factor, besides the compression and tension, to drive long bone mechano-adaptation.

Effect of early supervised progressive resistance training compared to unsupervised home-based exercise after fast-track total hip replacement applied to patients with preoperative functional limitations. A single-blinded randomised controlled trial

To examine if 2 weekly sessions of supervised progressive resistance training (PRT) in combination with 5 weekly sessions of unsupervised home-based exercise is more effective than 7 weekly sessions of unsupervised home-based exercise in improving leg-extension power of the operated leg 10 weeks after total hip replacement (THR) in patients with lower pre-operative function. A total of 73 patients scheduled for THR were randomised (1:1) to intervention group (IG, home based exercise 5 days/week and PRT 2 days/week) or control group (CG, home based exercise 7 days/week). The primary endpoint was change in leg extension power at 10 week follow up. Secondary outcomes were isometric hip muscle strength, sit-to-stand test, stair climb test, 20 m walking speed and patient-reported outcome (HOOS). Sixty-two completed the trial (85%). Leg extension power increased from baseline to the 10 week follow up in both groups; mean [95% CI] IG: 0.29 [0.13; 0.45] and CG: 0.26 [0.10; 0.42] W/kg, with no between-group difference (primary outcome) (P = 0.79). Maximal walking speed (P = 0.008) and stair climb performance (P = 0.04) improved more in the IG compared to CG, no other between-group differences existed. In this trial, supervised PRT twice a week in addition to 5 weekly sessions of unsupervised exercise for 10 weeks was not superior to 7 weekly sessions of unsupervised home-based exercise for 10 weeks in improving the primary outcome, leg-extension power of the operated leg, at the primary endpoint 10 weeks after surgery in THR patients with lower pre-operative function. NCT01214954.

Knee Extensor and Flexor Muscle Power Explains Stair Ascension Time in Patients With Unilateral Late-Stage Knee Osteoarthritis: A Cross-Sectional Study

ObjectivesTo determine the extent of asymmetrical deficits in knee extensor and flexor muscles, and to examine whether asymmetrical muscle deficits are associated with mobility limitations in persons with late-stage knee osteoarthritis (OA). DesignCross-sectional. SettingResearch laboratory. ParticipantsA clinical sample (N=56; age range, 50–75y) of eligible persons with late-stage knee OA awaiting knee replacement. InterventionsNot applicable. Main Outcome MeasuresKnee extensor and flexor power and torque assessed isokinetically; thigh muscle cross-sectional area (CSA) assessed by computed tomography; mobility limitation assessed by walking speed and stair ascension time; and pain assessed with the Western Ontario and McMaster Universities Osteoarthritis Index questionnaire. ResultsThe asymmetrical deficits in knee extensor and flexor power and torque were between 18% and 29% (P<.001). Regarding the thigh muscle CSA, the asymmetrical deficit was 4% (P<.001). Larger asymmetrical knee extensor power deficits and weaker knee extensor and flexor power on the contralateral side were associated with slower stair ascension times. Moreover, weaker knee extensor and flexor power on the ipsilateral side were associated with slower stair ascension times. Greater knee pain in the OA joint was independently associated with slower stair ascending time in both models. ConclusionsThe knee extensor and flexor muscle power of both the ipsilateral and contralateral sides and the pain in the OA knee were independently associated with stair ascension times. These results highlight the importance of assessing muscle power on both sides and knee pain in the prevention of mobility limitations in patients with knee OA.

Use of the Barthel index, activities of daily living, in dermatologic surgery in patients aged 80years and older.

Dermatologists often attend elderly patients with non-melanoma skin cancer (NMSC). There is a lack of information regarding the optimum treatment for elderly patients with NMSC. The objective of this study was to describe changes in the Barthel Index (BI) after dermatologic surgery for NMSC in patients aged 80 years and older. A prospective observational study was carried out in patients aged 80 years and older diagnosed with NMSC and treated with conventional dermatologic surgery. BI was performed by direct interview with the patients and/or their caregiver before the surgery, seven and 30 days after the surgery. A total of 180 dermatologic surgeries were performed in 144 patients. The average age of the patients was 84.2 years. There were 84 men (58.3%) and 60 women (41.7%). Mean BI score was 85.9 at baseline, 85.3 on day 7 after surgery, and 85.6 on day 30, showing minimal changes after dermatologic surgery. Changes in the BI occurred mainly in dressing, toilet use, transfers, mobility (on level surfaces) and walking stairs. Activities of daily living were not significantly affected in patients aged 80 years and older, after dermatologic surgery for NMSC.

G.P.3: Development of a disease severity scale for Becker muscular dystrophy

Becker muscular dystrophy (BMD) is characterized by progressive muscle weakness, with a large variation of disease progression. To investigate possible causes for this diversity it is necessary to compare the disease course between different BMD patients. Due to the rarity of the disease, it is difficult to compose and study large groups of patients of the same age. Therefore we have developed a model to enable comparison of disease severity in BMD patients of different ages. For this purpose, Dutch and Flemish DNA-confirmed BMD patients were interviewed using a standardized questionnaire focusing on the age at reaching five disease milestones: first motor symptoms, difficulty walking stairs, use of a walking aid, wheelchair dependence and mechanical home ventilation. Each patient received 10 points for the age at which a specific milestone was reached and an individual composite score was calculated for each age. Combining the results of all participants, a population mean score was calculated at each age individually. Information was gathered from 113 BMD patients, ranging in age from 6 to 66 (median 39) years. Estimated mean survival for reaching the individual disease milestones was: first motor symptoms 11years (SE 0.92; <i>n</i>=109), difficulties walking stairs 25years (SE 1.5; <i>n</i>=90), use of a walking aid 37years (SE 1.8; <i>n</i>=71), wheelchair dependence 50years (SE 2.0; <i>n</i>=35) and mechanical home ventilation 63years (SE 1.2; <i>n</i>=5). Out of all individual data a model for disease severity was calculated. The maximum score in this model was 50 points. Mean population scores at age 10, 20, 30, 40, 50 and 60years respectively were 8.4, 16.7, 20.2, 23.7, 26.8 and 30. When combining these mean scores with their SD, individual <i>Z</i>-scores can be calculated, enabling comparison of disease severity in BMD patients of different ages. As long as no prospectively collected long-term follow-up data are available, this scale could form a useful tool for clinical research in BMD.

QUADRICEPS STRENGTH, KNEE PAIN AND FUNCTIONAL PERFORMANCE WITH PATELLAR TAPING IN KNEE OSTEOARTHRITIS

Background: Patellar taping has long been reported to be effective in relieving pain in patients with patello-femoral pain syndrome (PFPS). Yet, there is lack of knowledge that supports its use in knee osteoarthritis (OA) management. Purpose: This study examined the effect of therapeutic patellar taping on concentric and eccentric quadriceps muscle peak torques, VAS pain scores, 6-minute walking distance and stair climbing time in patients with knee OA. Methods: A total of 30 female patients with symptomatic knee OA with mean age 51.8 ± 6.3 years and BMI 32.56 ± 3.26 m2/kg participated in the study. They were tested under three taping conditions that were tested randomly; therapeutic, placebo and no-tape. Results: Repeated measure MANOVA revealed that the quadriceps muscle peak torques and 6-minute walking distance increased significantly (p &lt; 0.05) and the VAS scores and stair climbing time decreased significantly with therapeutic tape use compared with the other two tapes. Moreover, the quadriceps muscle peak torques increased significantly and the VAS scores decreased significantly with placebo tape use compared with no-tape use, with no significant difference (p &gt; 0.05) in between for the 6-minute walking distance and stair climbing time. Conclusion: The findings indicate that therapeutic patellar taping is effective in improving quadriceps strength and functional performance and reducing pain in patients with knee OA.

Effects of an Anterior Ankle-Foot Orthosis on Walking Mobility in Stroke Patients: Get Up and Go and Stair Walking

ObjectiveTo examine the effects of an anterior ankle-foot orthosis (AAFO) on walking mobility in stroke patients. DesignCross-sectional and repeated-measures study design. SettingA university's neurologic rehabilitation department. ParticipantsAmbulant stroke patients (N=21). InterventionsNot applicable. Main Outcome MeasuresWalking mobility was measured by the Timed Up and Go (TUG) test and the Timed Up and Down Stairs (TUDS) test. The paired t test was used to determine the difference between the mobility performances measured with and without the AAFO. ResultsThere were significant differences between mobility performances with and without an AAFO in the TUG test (P=.038) and the TUDS test (P=.000). ConclusionsThis study supports the effect of an AAFO on walking mobility in stroke patients. The findings demonstrate that stroke patients wearing an AAFO may ambulate with greater speed and safety on level surfaces and stairs.

Whole-body angular momentum during stair walking using passive and powered lower-limb prostheses*

Individuals with a unilateral transtibial amputation have a greater risk of falling compared to able-bodied individuals, and falling on stairs can lead to serious injuries. Individuals with transtibial amputations have lost ankle plantarflexor muscle function, which is critical for regulating whole-body angular momentum to maintain dynamic balance. Recently, powered prostheses have been designed to provide active ankle power generation with the goal of restoring biological ankle function. However, the effects of using a powered prosthesis on the regulation of whole-body angular momentum are unknown. The purpose of this study was to use angular momentum to evaluate dynamic balance in individuals with a transtibial amputation using powered and passive prostheses relative to able-bodied individuals during stair ascent and descent. Ground reaction forces, external moment arms, and joint powers were also investigated to interpret the angular momentum results. A key result was that individuals with an amputation had a larger range of sagittal-plane angular momentum during prosthetic limb stance compared to able-bodied individuals during stair ascent. There were no significant differences in the frontal, transverse, or sagittal-plane ranges of angular momentum or maximum magnitude of the angular momentum vector between the passive and powered prostheses during stair ascent or descent. These results indicate that individuals with an amputation have altered angular momentum trajectories during stair walking compared to able-bodied individuals, which may contribute to an increased fall risk. The results also suggest that a powered prosthesis provides no distinct advantage over a passive prosthesis in maintaining dynamic balance during stair walking.

Kinetic comparison of older men and women during walk-to-stair descent transition

Stair walking is one of the most challenging tasks for older adults, with women reporting higher incidence of falls. The purpose of this study was to investigate the gender differences in kinetics during stair descent transition. Twenty-eight participants (12 male and 16 female; 68.5 and 69.0 years of mean age, respectively) performed stair descent from level walking in a step-over-step manner at a self-selected speed over a custom-made three-step staircase with embedded force plates. Kinematic and force data were combined using inverse dynamics to generate kinetic data for gender comparison. The top and the first step on the staircase were chosen for analysis. Women showed a higher trail leg peak hip abductor moment (−1.0Nm/kg), lower trail leg peak knee extensor moment and eccentric power (0.74Nm/kg and 3.15W/kg), and lower peak concentric power at trail leg ankle joint (1.29W/kg) as compared to men (p<0.05; −0.82Nm/kg, 0.89Nm/kg, 3.83W/kg, and 1.78W/kg, respectively). The lead leg knee eccentric power was also lower in women (p<0.05). This decreased ability to exert knee control during stair descent transition may predispose women to a higher risk of fall.

A study of the inter-rater reliability of a test battery for use in patients after total hip replacement

Objective: To assess the within-day inter-rater reliability of a test battery of functional performance, muscle strength and leg extension power on total hip replacement patients. Design: A test–retest design was used. Setting: Orthopaedic department at a Regional Hospital in Denmark. Subjects: Two convenience samples of 20 total hip replacement patients were included. Intervention: The tests were performed three months after total hip replacement. Two raters performed test and re-test, with two hours rest in-between. Main measures: The test battery included: sit-to-stand performance, 20-metre maximum walking speed, stair climb performance, isometric muscle strength (hip abduction/flexion), and leg extension power. Absolute reliability was assessed with Bland Altman plots, standard error of measurement (SEM), and minimal detectable change. Relative reliability was assessed with intra-class correlation coefficient. Results: Systematic differences between testers were seen in tests of walking speed (0.32 seconds p = 0.03) and stair climb performance (0.18 seconds p = 0.003). In per cent of the grand mean, the standard error of measurement was 3%–10%, indicating the measurement error on a group level, and the minimal detectable change was 10%–27%, indicating the measurement error on an individual level. The intra-class correlation coefficients were above 0.80 in all tests (range 0.83–0.95). Conclusions: The tests showed acceptable relative and absolute inter-rater reliability on a group level, but not on an individual level (except from test of walking speed and stair climb performance). Systematic differences between testers were considered clinically irrelevant (0.3 and 0.2 seconds).

Fast-Track Versus Standard Care in Laparoscopic High Anterior Resection

The value of fast-track (FT) multimodal recovery programs in improving hospitalization of surgical patients has been widely proved. The application of FT protocols to laparoscopic colorectal surgery seems to maximize the effects of the minimally invasive approach. The objectives of this randomized-controlled trial are to compare the short-term outcomes (bowel function, return to oral nutrition, day of discharge, fatigue, time to resume normal activities, functional capabilities, and readmission rate) of patients undergoing elective laparoscopic high anterior resection (HAR) following either a FT or a standard program. The prospective randomized-controlled trial included 52 consecutive patients undergoing elective laparoscopic HAR. Group 1 was treated with a FT rehabilitation program, and group 2 was treated with a standard care (SC) program. Patients were interviewed 14 and 30 days postoperatively. One patient in each group was excluded from the study. Mean hospital stay, time of first bowel movement, and bowel function resumption were significantly shorter in the FT group (P<0.05). Patients in the FT group referred more pain in day 0 versus patients in the SC group (P<0.05) even though the difference disappeared from day 1. Fatigue was significantly reduced at day 14 in the FT group compared with the SC group (P<0.01). Similarly, ability to resume the normal preoperative attitude (walking stairs, cooking, housekeeping, shopping, and walking outdoors) was significantly better at day 14 in the FT group (P<0.005). There was no significant difference between the 2 groups at day 30 for the same parameters. There were no readmissions in both the groups and no need for consultations from general practitioners. FT multimodal program is a safe approach effective on postoperative short-term outcome significantly reducing hospital stay. Early postoperative pain control needs to be optimized.

Serum biochemical markers of joint metabolism and inflammation in relation to clinical symptoms and physical function in adults with symptomatic knee osteoarthritis

Purpose: To date, the majority of osteoarthritis (OA) biomarker research has examined associations between biomarker levels and radiographic parameters. While radiography provides information on the structural burden of disease, it is insensitive to small changes in cartilage metabolism and does not always correlate with the most significant clinical expression in OA, pain. The purpose of this study was to investigate the associations between joint metabolism and inflammation with pain and physical function in adults with painful knee OA. This is in support of qualifying burden of disease biomarkers with clinical variables to support the study, management, and understanding of disease pathology in OA. Methods: The study used baseline data from 54 adults with knee OA participating in a nutrition intervention study. The 100 mm visual analogue scale version of theWestern Ontario andMcMaster University Osteoarthritis Index (WOMAC) was used to assess pain, stiffness, and physical disability. A minimumWOMAC pain score of 125 was used as a cutoff for participant inclusion. Physical functionwas assessed with a 6minute walk test (:6MWT) and stair climb task (SCT). Serum concentrations of biomarkers included measures of cartilage degradation (cartilage oligomeric matrix protein [COMP]), cartilage synthesis (typeIIA collagen N-propeptide [PIIANP]), synovial metabolism (hyaluronic acid [HA]), cartilage degrading enzyme levels (matrix metalloproteinase 3 [MMP-3]), and inflammation (C-reactive protein [CRP]). COMP, PIIANP, HA, and MMP-3 were measured by enzyme-linked immunosorbent assay and CRP was measured by an immunoturbidimetric assay. Correlations between biomarkers and clinical variables were assessed using Spearman correlation coefficients. Results: Participants (38 females and 16 males) had a mean age of 60 11.9 years, BMI of 32.6 7.5 kg/m2, disease duration of 86.6 112.2 months, and WOMAC pain score of 193.4 94.04 mm. Higher serum MMP-3 levels were significantly associated with higher WOMAC pain scores (R 1⁄4 0.27, p 1⁄4 0.05), controlling for age and body mass index (BMI). Higher levels of serum HA were significantly associated with decreased walking distance in the :6MWT (R 1⁄4 -0.35, p 1⁄4 0.01) and longer time taken in the SCT (R 1⁄4 0.31, p 1⁄4 0.02), when controlling for age and BMI. Higher CRP levels were significantly associated with higher WOMAC physical disability score (R 1⁄4 0.34, p 1⁄4 0.01) and worse performance in the :6MWT (R1⁄4 -0.38, p1⁄4 0.005) and SCT (R1⁄4 0.44, p1⁄4 0.001) when age was controlled for, but these associations were not significant when BMI was controlled for. COMP and PIIANP were not significantly associated with any clinical variables analyzed. Conclusion: SerumMMP-3 levels were associated with pain and serum HA levels were associated with physical functioning in adults who suffer from mild to moderate pain and impaired physical functioning from knee OA. Previous studies have shown that HA and MMP-3 are related to structural knee parameters in OA. Therefore, results from this study demonstrate that serum HA and MMP-3 also have potential as qualified burden of disease biomarkers that are clinically meaningful. (Research supported by the Ontario Ministry of Agriculture, Food and Rural Affairs, project #200121).

Gait event detection during stair walking using a rate gyroscope.

Gyroscopes have been proposed as sensors for ambulatory gait analysis and functional electrical stimulation systems. These applications often require detection of the initial contact (IC) of the foot with the floor and/or final contact or foot off (FO) from the floor during outdoor walking. Previous investigations have reported the use of a single gyroscope placed on the shank for detection of IC and FO on level ground and incline walking. This paper describes the evaluation of a gyroscope placed on the shank for determination of IC and FO in subjects ascending and descending a set of stairs. Performance was compared with a reference pressure measurement system. The absolute mean difference between the gyroscope and the reference was less than 45 ms for IC and better than 135 ms for FO for both activities. Detection success was over 93%. These results provide preliminary evidence supporting the use of a gyroscope for gait event detection when walking up and down stairs.

Validation and Comparison of Two Methods to Assess Human Energy Expenditure during Free-Living Activities

BackgroundThe measurement of activity energy expenditure (AEE) via accelerometry is the most commonly used objective method for assessing human daily physical activity and has gained increasing importance in the medical, sports and psychological science research in recent years.ObjectiveThe purpose of this study was to determine which of the following procedures is more accurate to determine the energy cost during the most common everyday life activities; a single regression or an activity based approach. For this we used a device that utilizes single regression models (GT3X, ActiGraph Manufacturing Technology Inc., FL., USA) and a device using activity-dependent calculation models (move II, movisens GmbH, Karlsruhe, Germany).Material and MethodsNineteen adults (11 male, 8 female; 30.4±9.0 years) wore the activity monitors attached to the waist and a portable indirect calorimeter (IC) as reference measure for AEE while performing several typical daily activities. The accuracy of the two devices for estimating AEE was assessed as the mean differences between their output and the reference and evaluated using Bland-Altman analysis.ResultsThe GT3X overestimated the AEE of walking (GT3X minus reference, 1.26 kcal/min), walking fast (1.72 kcal/min), walking up−/downhill (1.45 kcal/min) and walking upstairs (1.92 kcal/min) and underestimated the AEE of jogging (−1.30 kcal/min) and walking upstairs (−2.46 kcal/min). The errors for move II were smaller than those for GT3X for all activities. The move II overestimated AEE of walking (move II minus reference, 0.21 kcal/min), walking up−/downhill (0.06 kcal/min) and stair walking (upstairs: 0.13 kcal/min; downstairs: 0.29 kcal/min) and underestimated AEE of walking fast (−0.11 kcal/min) and jogging (−0.93 kcal/min).ConclusionsOur data suggest that the activity monitor using activity-dependent calculation models is more appropriate for predicting AEE in daily life than the activity monitor using a single regression model.

Whole-body angular momentum during stair ascent and descent

The generation of whole-body angular momentum is essential in many locomotor tasks and must be regulated in order to maintain dynamic balance. However, angular momentum has not been investigated during stair walking, which is an activity that presents a biomechanical challenge for balance-impaired populations. We investigated three-dimensional whole-body angular momentum during stair ascent and descent and compared it to level walking. Three-dimensional body-segment kinematic and ground reaction force (GRF) data were collected from 30 healthy subjects. Angular momentum was calculated using a 13-segment whole-body model. GRFs, external moment arms and net joint moments were used to interpret the angular momentum results. The range of frontal plane angular momentum was greater for stair ascent relative to level walking. In the transverse and sagittal planes, the range of angular momentum was smaller in stair ascent and descent relative to level walking. Significant differences were also found in the ground reaction forces, external moment arms and net joint moments. The sagittal plane angular momentum results suggest that individuals alter angular momentum to effectively counteract potential trips during stair ascent, and reduce the range of angular momentum to avoid falling forward during stair descent. Further, significant differences in joint moments suggest potential neuromuscular mechanisms that account for the differences in angular momentum between walking conditions. These results provide a baseline for comparison to impaired populations that have difficulty maintaining dynamic balance, particularly during stair ascent and descent.

Active control of a powered ankle‐foot prosthesis

Amputees suffer a higher metabolic demand on their bodies. Passive prostheses seek to reduce this deficit through elastic distribution of the energy inherently dissipated in walking. Yet with no capacity to generate torque they lack truly biomimetic function. The active prosthesis is a solution to this and opens up a world of active control in the timing and magnitude of energy return. Being able to also modulate the dynamic character of the replaced joint, in impedance and position, brings us closer to a true model of the ankle-foot complex. And so the ankle-foot complex can be seen to be modelled as a visco-elastic system with loading and unloading phases and active power output. It was identified that the concept of the active automobile suspension system designed by Bose has the capacity to satisfy these functional demands and so was investigated as a viable model for a prosthetic device. In using this model, the ankle joint was modelled as a motor, driven in drive and dynamo modes to convert an elastic system into an electromagnetic system based around a battery. Low power drain derived from significant power recovery makes this concept particularly interesting. The versatility of this concept is regarded as approaching that of the human beyond those devices that rely on passive or fixed elastic systems. This is active elasticity. A CAD model was generated along with a corresponding control scheme. The control system is proposed as a viable and innovative concept for future prosthetics with great potential for development. This proposal makes use of underfoot sensors to determine the displacement of the fore and aft sections of the foot above ground, and is proposed as an effective sensory concept to facilitate handling of various terrain including slopes and stairs. The concept is seen as highly versatile in this respect. Models for both slope and stair walking have been implemented. An exponential function was proposed as a model for the action of impedance at the ankle. This is a highly versatile function that can be matched, using discrete tuning parameters, to each phase of stance against a majority of samples during level walking. This function also facilitates the smooth and controlled contact between the foot and the ground when combined with the underfoot sensors. The concept is not fully developed but has been initiated. Much further work is possible. Thesis Supervisor: Professor Andrzej Ordys November 2013 Figure 1 Torque-angle, or stiffness profile derived from exponential function. (Figure ​(Figure11 inspired largely by [1] as a means of comparison to a typical torque-angle profile.)

The effects of stair walking training on the balance ability of chronic stroke patients.

[Purpose] The purpose of this study was to evaluate the effects of stair walking training on balance ability of chronic stroke patients. [Subjects and Methods] Forty stroke patients were allocated equally and randomly to an experimental group and a control group. The experimental group undertook 30 minutes of training therapy and 30 minutes of walking exercise on stairs with flat surfaces. The control group undertook 30 minutes went of training therapy and 30 minutes of walking exercise on a flat surface. All the participants had five training sessions each week for four weeks. A Biorescue system was used to measure the weight-bearing footprint, anterior length in the limit of stability, posterior length in the limit of stability, surface area ellipse of Romberg, and length of Romberg before and after the training. [Results] With regard to changes in the weight-bearing footprint, the anterior length in the limit of stability, and the posterior length in the limit of stability, there were significant differences on both the paretic and nonparetic sides, and there were also significant differences in the surface area ellipse of Romberg and length of Romberg after the intervention. [Conclusion] The experiment results showed that walking exercise on stairs is effective in enhancing balance performance. The same exercise can be applied to patients with other types of neurological disorders to improve their balance.

Comparison of effect of Two Group of Proprioceptive Exercises in Osteoarthritis Patients on Knee Muscle Strengh and Functional Activity

Osteoarthritis also known as degenerative arthritis or degenerative joint disease is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone. OA commonly affects the hands, feet, spine, and the large weight bearing joints, such as the hips and knees. Research have demonstrated that knee proprioception is effected in knee OA patients. Functional consequences of impaired proprioception may include lower gait velocity, shorter stride length, and slower stair walking time. Improved knee function is possible with changes in proprioception.