The use of a lateral wedge insole to reduce knee loading when ascending and descending stairs in medial knee osteoarthritis patients

Background

Stair climbing is a challenging task to the elderly being the task with the first complaint in patients with mild to moderate knee osteoarthritis. Stair climbing results in around six times more compressive load transmitted through the knee joint than walking on level ground. The purpose of this study was to assess whether lateral wedge insoles would reduce medial compartment knee loading when ascending and descending stairs in patients with medial knee osteoarthritis.

Methods

Eight patients with medial knee osteoarthritis were tested in random order with and without a pair of 5° off-the-shelf lateral wedge insoles for two separate activities (stair ascent and stair descent). Kinematic and kinetic data were collected for the lower extremity using a sixteen camera motion capture system and two force plates. Primary outcome measures were the external knee adduction moment and the knee adduction angular impulse.

Findings

During stair ascent and descent, lateral wedge insoles significantly (P < 0.05) reduced the 1st peak external knee adduction moment in early stance (ascent 6.8%, descent 8.4%), the trough in mid stance (ascent 13%, descent 10.7%), 2nd peak in the late stance (ascent 15%, descent 8.3%) and the knee adduction angular impulse compared to the control (standard shoe) with large effect sizes (0.75–0.95).

Interpretation

In this first study on stairs, lateral wedge insoles consistently reduced the overall magnitude of medial compartment loading during stair ascent and descent. Further research is needed to determine the relationship of this with clinical results when ascending and descending stairs with lateral wedge insoles.     

Comparison of gluteus medius muscle activity during functional tasks in individuals with and without osteoarthritis of the hip joint

Background

Neuromuscular alterations have been reported for patients with osteoarthritis of the hip joint; however, the underlying cause associated with altered gluteus medius muscle function has not been examined. This study assessed electromyographic amplitudes of the gluteus medius muscles during function in patients with unilateral end-stage osteoarthritis of the hip joint compared to controls.

Methods

Patients with unilateral end-stage hip joint osteoarthritis (n = 13) and asymptomatic control participants (n = 17) participated. Average root-mean squared muscle amplitudes represented as a percent of maximum voluntary isometric contraction for both the involved and uninvolved limb gluteus medius muscles were analyzed during step up, step down, and gait. The association between muscle activation and impact forces during stepping tasks was assessed.

Findings

Patients with hip osteoarthritis exhibited increased gluteus medius muscle electromyographic amplitudes bilaterally during stair ascent, stair descent, and gait compared to controls, regardless of which limb they led. Involved limb muscle activity was inversely related to impact force during step down onto the ipsilateral limb.

Interpretation

Patients with hip osteoarthritis demonstrated increased gluteus medius muscle activation levels during stepping tasks and gait when compared to controls. The increased activation is most likely a compensatory response to muscle weakness. Therefore, application of strengthening exercises which target the gluteal muscles should assist in neuromuscular control and result in improved strength for patients with hip joint osteoarthritis.     

Effects of Age and Gender on Dynamic Stability During Stair Descent

Objective

To determine the effects of age and sex and their interaction effects on dynamic postural stability during stair descent.

Design

Cross sectional.

Setting

Laboratory.

Participants

Healthy younger adults (N=28) and healthy older adults (N=21).

Interventions

Not applicable.

Main Outcome Measures

Spatiotemporal gait parameters, displacement of center of mass (COM), instantaneous velocity of the COM, divergence between vertical projection of the COM, and center of pressure (COP).

Results

Interaction effects of age and sex were found in stride duration, COM displacement, and instantaneous velocity of the COM in the mediolateral direction. Older adults demonstrated longer stride duration with shorter double-limb stance and longer single-limb stance during stair descent. Women have significantly longer stride duration than men. The effects of sex and age were significant in the data normalized by height. Older adults and women demonstrated larger peak-to-peak COM displacement, peak instantaneous velocity of the COM, and COM-COP divergence than the younger individuals and men, respectively. Peak instantaneous velocity of the COM was significant different in most pairwise comparisons, but the COM-COP divergence was significantly different in several comparisons.

Conclusions

This study examined the COM and COP parameters to quantify dynamic stability during stair descent across sex and age. Although older women descended stairs successfully, they demonstrated differences in control of instantaneous velocity of the COM compared with the other participants. Dynamic instability could be detected by examining the control of instantaneous velocity of the COM. In developing a better understanding of the balance control of stair descent in healthy older adults, aging patients with various pathologies can be better assessed, appropriately treated, and provided with proper assistive devices.     

Stair negotiation time in community-dwelling older adults: normative values and association with functional decline

Oh-Park M, Wang C, Verghese J. Stair negotiation time in community-dwelling older adults: normative values and association with functional decline.

Objectives

To establish reference values for stair ascent and descent times in community-dwelling, ambulatory older adults, and to examine their predictive validity for functional decline.

Design

Longitudinal cohort study. Mean follow-up time was 1.8 years (maximum, 3.2y; total, 857.9 person-years).

Setting

Community sample.

Participants

Adults 70 years and older (N=513; mean age, 80.8±5.1y) without disability or dementia.

Interventions

Not applicable.

Main Outcome Measures

Time to ascend and descend 3 steps measured at baseline. A 14-point disability scale assessed functional status at baseline and at follow-up interviews every 2 to 3 months. Functional decline was defined as an increase in the disability score by 1 point during the follow-up period.

Results

The mean±SD stair ascent and descent times for 3 steps were 2.78±1.49 and 2.83±1.61 seconds, respectively. The proportion of self-reported and objective difficulty was higher with longer stair ascent and descent times (P<.001 for trend for both stair ascent and descent). Of the 472 participants with at least 1 follow-up interview, 315 developed functional decline, with a 12-month cumulative incidence of 56.6% (95% confidence interval [CI], 52.1%–61.3%). The stair negotiation time was a significant predictor of functional decline after adjusting for covariates including gait velocity (adjusted hazard ratio [aHR] per 1-s increase: aHR=1.12 [95% CI, 1.04–1.21] for stair ascent time; aHR=1.15 [95% CI, 1.07–1.24] for stair descent time). Stair descent time was a significant predictor of functional decline among relatively high functioning older adults reporting no difficulty in stair negotiation (P=.001).

Conclusions

The stair ascent and descent times are simple, quick, and valid clinical measures for assessing the risk of functional decline in community-dwelling older adults including high-functioning individuals.     

A Preliminary Study to Identify Locomotor-Cognitive Dual Tasks That Reveal Persistent Executive Dysfunction After Mild Traumatic Brain Injury

Objective

To identify different combinations of physical (level, obstacle avoidance, stepping down) and cognitive (visual, mental) demands within a locomotor navigational context that best discriminates between persons with mild traumatic brain injury (MTBI) and control subjects for an eventual clinical tool to assess residual executive dysfunction.

Design

Group comparison study.

Setting

Rehabilitation facility.

Participants

Volunteer sample (N=14) of persons with MTBI (n=7) (6 women; age, 20±1.6y) and a comparison group (n=7) of subjects without neurologic problems (6 women; age, 22.4±1.4y).

Interventions

Not applicable.

Main Outcome Measures

Gait speed (m/s) and dual-task cost calculated as the relative change in gait speed from single (no cognitive task) to dual tasks for the same gait condition.

Results

There were significant interactions between groups and cognitive tasks and between groups and cognitive and physical tasks for gait speed. Specifically, the MTBI group walked slower than control subjects in the dual-task conditions when stepping over an obstacle combined with each cognitive task. When gait speed was measured as dual-task costs, group differences were more evident, except for stepping down.

Conclusions

These preliminary results suggest that both absolute gait speed and calculated dual-task costs during the combination of stepping over an obstacle with a simultaneous cognitive task are sensitive to revealing executive dysfunction in persons with MTBI. Gait speed can be easily measured in the clinic to provide important information to make diagnoses and decide about return to play or function. Continued work building on these preliminary results is needed toward the development of a clinical tool.     

Gait and gait-related activities of daily living after total hip arthroplasty: A systematic review

Background

Differences in the performance of gait and gait-related activities of daily living are known to persist after total hip arthroplasty compared to healthy controls, but the specific underlying deficits (spatiotemporal, kinematics and kinetics) are not completely understood. This review aimed to map the differences between patients and controls, and between the operated and non-operated limbs during various activities of daily living.

Methods

A computerized search with broad search terms was performed in the MEDLINE database. Primary inclusion criteria were: primary osteoarthritis as indication, comparison with healthy controls or comparison between the operated and the non-operated limbs, and follow-up period at least six months after surgery.

Findings

The literature search yielded 2177 citations, of which 35 articles were included. Compared to controls, reductions were identified in the operated hip in sagittal range of motion, peak extension, sagittal power generation, abduction moment and external rotation moment. During stair ascent, these reductions did not become more apparent, although deficits in hip kinetics in all three planes were found. Walking speed and step length were reduced compared to controls at longer-term follow-up, but not at short-term follow-up.

Interpretation

The hip abduction moment deficit was present both in level walking and in stair ascent in total hip arthroplasty patients compared to controls. Reduced sagittal hip power generation and external rotation moment were also found, of which the clinical relevance remains to be established. Due to a low number of studies, many of the longer-term effects of THA on gait and gait-related ADL are not yet accurately known.     

Kinematic analyses during stair descent in young women with patellofemoral pain

Background

Compensatory movement strategies may develop in response to pain to avoid stress on the affected area. Patellofemoral pain is characterised by intermittent periods of pain and the present study addresses whether long-term pain leads to compensatory movement strategies that remain even when the pain is absent.

Method

Lower extremity kinematics in three dimensions was studied in stair descent in 17 women with patellofemoral and in 17 matched controls. A two-dimensional geometric model was constructed to normalise kinematic data for subjects with varying anthropometrics when negotiating stairs of fixed proportions.

Results

There were minor differences in movement patterns between groups. Knee joint angular velocity in the stance leg at foot contact was lower and the movement trajectory tended to be jerkier in the patellofemoral group. The two-dimensional model showed greater plantar flexion in the swing leg in preparation for foot placement in the patellofemoral group.

Interpretation

The results indicate that an altered stair descent strategy in the patellofemoral group may remain also in the absence of pain. The biomechanical interpretation presumes that the strategy is aimed to reduce knee joint loading by less knee joint moment and lower impact force.     

The influence of an auditory-memory attention-demanding task on postural control in blind persons

Background

In order to evaluate the effect of an auditory–memory attention-demanding task on balance control, nine blind adults were compared to nine age–gender-matched sighted controls. This issue is particularly relevant for the blind population in which functional assessment of postural control has to be revealed through “real life” motor and cognitive function. The study aimed to explore whether an auditory–memory attention-demanding cognitive task would influence postural control in blind persons and compare this with blindfolded sighted persons.

Methods

Subjects were instructed to minimize body sway during narrow base upright standing on a single force platform under two conditions: 1) standing still (single task); 2) as in 1) while performing an auditory–memory attention-demanding cognitive task (dual task). Subjects in both groups were required to stand blindfolded with their eyes closed. Center of Pressure displacement data were collected and analyzed using summary statistics and stabilogram-diffusion analysis.

Findings

Blind and sighted subjects had similar postural sway in eyes closed condition. However, for dual compared to single task, sighted subjects show significant decrease in postural sway while blind subjects did not.

Interpretation

The auditory–memory attention-demanding cognitive task had no interference effect on balance control on blind subjects. It seems that sighted individuals used auditory cues to compensate for momentary loss of vision, whereas blind subjects did not. This may suggest that blind and sighted people use different sensorimotor strategies to achieve stability.     

Pressure characteristics at the stump/socket interface in transtibial amputees using an adaptive prosthetic foot

Background

The technological advances that have been made in developing highly functional prostheses are promising for very active patients but we do not yet know whether they cause an increase in biomechanical load along with possibly negative consequences for pressure conditions in the socket. Therefore, this study monitored the socket pressure at specific locations of the stump when using a microprocessor-controlled adaptive prosthetic ankle under different walking conditions.

Methods

Twelve unilateral transtibial amputees between 43 and 59 years of age were provided with the Proprio-Foot™ (Össur) and underwent an instrumented 3D gait analysis in level, stair, and incline walking, including synchronous data capturing of socket pressure. Peak pressures and pressure time integrals (PTI) at three different locations were compared for five walking conditions with and without using the device’s ankle adaptation mode.

Findings

Highest peak pressures of 2.4 kPa/kg were found for incline ascent at the calf muscle as compared to 2.1 kPa/kg in level walking with large inter-individual variance. In stair ascent a strong correlation was found between maximum knee moment and socket pressure. The most significant pressure changes relative to level walking were seen in ramp descent anteriorly towards the stump end, with PTI values being almost twice as high as those in level walking. Adapting the angle of the prosthesis on stairs and ramps modified the pressure data such that they were closer to those in level walking.

Interpretation

Pressure at the stump depends on the knee moments involved in each walking condition. Adapting the prosthetic ankle angle is a valuable means of modifying joint kinetics and thereby the pressure distribution at the stump. However, large inter-individual differences in local pressures underline the importance of individual socket fitting.     

Use of a geared wheelchair wheel to reduce propulsive muscular demand during ramp ascent: Analysis of muscle activation and kinematics

Background

Shoulder muscle overuse has been linked to the high prevalence of shoulder injuries in manual wheelchair users. Ramp ascent is a barrier that is often faced by manual wheelchair users that requires higher muscle activations than level wheelchair propulsion. Additionally, reported subjective measures of shoulder pain are reduced amongst manual wheelchair users when using a wheelchair wheel outfitted with a gear mechanism. The purpose of the current investigation was to investigate shoulder muscle activation levels and upper limb kinematics during ramp ascent with and without the use of a geared wheel.

Methods

Thirteen healthy participants (6 male and 7 female) performed ramp ascent on four ramp grades (1:12, 1:10, 1:8, 1:6) using three wheel conditions (gear, no gear, standard). Electromyographic (EMG) activity of select shoulder muscles as well as kinematics of the right upper limb were collected during ramp ascent. Peak and integrated EMG as well as peak wrist, elbow, and shoulder kinematics were obtained from all ramp ascent trials.

Findings

Peak EMG of the shoulder flexors decreased by an average of 17% (P ? 0.0229) during ramp ascent with the geared wheel. Integrated EMG increased by 67% (P ? 0.0034) as a consequence of an 86% increase (P = 0.0009) in ramp ascent duration during the geared wheel condition. There were no significant differences between the non-geared and standard wheel conditions.

Interpretation

Caution must be used if using the gear ratio for prolonged periods due to potential for muscle fatigue since the overall muscle effort to move a fixed distance is higher with the gear ratio. Reducing peak demands may benefit wheelchair users with performing more strenuous tasks of daily living.     

Functional performance of a total ankle replacement: thorough assessment by combining gait and fluoroscopic analyses

Background

A thorough assessment of patients after total ankle replacement during activity of daily living can provide complete evidence of restored function in the overall lower limbs and replaced ankle. This study analyzes how far a possible restoration of physiological mobility in the replaced ankle can also improve the function of the whole locomotor apparatus.

Methods

Twenty patients implanted with an original three-part ankle prosthesis were analyzed 12 months after surgery during stair climbing and descending. Standard gait analysis and motion tracking of the components by three-dimensional fluoroscopic analysis were performed on the same day using an established protocol and technique, respectively.

Findings

Nearly physiological ankle kinematic, kinetic and electromyography patterns were observed in the contralateral side in both motor activities, whereas these patterns were observed only during stair climbing in the operated side. Particularly, the mean ranges of flexion at the replaced ankle were 13° and 17° during stair climbing and descending, respectively. Corresponding 2.1 and 3.1 mm antero/posterior meniscal-to-tibial translations were correlated with flexion between the two metal components (p < 0.05). In addition, a larger tibiotalar flexion revealed by fluoroscopic analysis resulted in a physiological hip and knee moment.

Interpretation

The local and global functional performances of these patients were satisfactory, especially during stair climbing. These might be associated to the recovery of physiological kinematics at the replaced ankle, as also shown by the consistent antero/posterior motion of the meniscal bearing, according to the original concepts of this ankle replacement design.     

Postural control strategies during single limb stance following acute lateral ankle sprain

Background

Single-limb stance is maintained via the integration of visual, vestibular and somatosensory afferents. Musculoskeletal injury challenges the somatosensory system to reweight distorted sensory afferents. This investigation supplements kinetic analysis of eyes-open and eyes-closed single-limb stance tasks with a kinematic profile of lower limb postural orientation in an acute lateral ankle sprain group to assess the adaptive capacity of the sensorimotor system to injury.

Methods

Sixty-six participants with first-time acute lateral ankle sprain completed a 20 second eyes-open single-limb stance task on their injured and non-injured limbs (task 1). Twenty-three of these participants successfully completed the same 20 second single-limb stance task with their eyes closed (task 2). A non-injured control group of 19 participants completed task 1, with 16 completing task 2. 3-dimensional kinematics of the hip, knee and ankle joints, as well as associated fractal dimension of the center-of-pressure path were determined for each limb during these tasks.

Findings

Between trial analyses revealed significant differences in stance limb kinematics and fractal dimension of the center-of-pressure path for task 2 only. The control group bilaterally assumed a position of greater hip flexion compared to injured participants on their side-matched “involved”(7.41 [6.1°] vs 1.44 [4.8]°; η² = .34) and “uninvolved” (9.59 [8.5°] vs 2.16 [5.6°]; η² = .31) limbs, with a greater fractal dimension of the center-of-pressure path (involved limb = 1.39 [0.16°] vs 1.25 [0.14°]; uninvolved limb = 1.37 [0.21°] vs 1.23 [0.14°]).

Interpretation

Bilateral impairment in postural control strategies present following a first time acute lateral ankle sprain.     

Femoral shaft strains during daily activities: Implications for atypical femoral fractures

Background

Atypical femoral fractures are low-energy fractures initiating in the lateral femoral shaft. We hypothesized that atypical femoral fracture onset is associated with daily femoral strain patterns. We examined femoral shaft strains during daily activities.

Methods

We analyzed earlier calculations of femoral strain during walking, sitting and rising from a chair, stair ascent, stair descent, stepping up, and squatting based on anatomically consistent musculoskeletal and finite-element models from a single donor and motion recordings from a body-matched volunteer. Femoral strains in the femoral shaft were extracted for the different activities and compared. The dependency between femoral strains in the lateral shaft and kinetic parameters was studied using multi-parametric linear regression analysis.

Findings

Tensile strain in the lateral femoral shaft varied from 327 με (squatting) to 2004 με (walking). Walking and stair descent imposed tensile loading on the lateral shaft, whereas the other activities mainly imposed tensile loads on the anterior shaft. The multi-parametric linear regression showed a moderately strong correlation between tensile strains in the lateral shaft and the motion kinetic (joint moments and ground reaction force) in the proximal (R² = 0.60) and the distal shaft (R² = 0.46).

Interpretation

Bone regions subjected to tensile strains are associated with atypical femoral fractures. Walking is the daily activity that induces the highest tensile strain in the lateral femoral shaft. The kinetics of motion explains 46%–50% of the tensile strain variation in the lateral shaft, whereas the unexplained part is likely to be attributed to the way joint moments are decomposed into muscle forces.     

Postural stability and ankle sprain history in athletes compared to uninjured controls

Background

Diminished postural stability is a risk factor for ankle sprain occurrence and ankle sprains result in impaired postural stability. To date, ankle sprain history has not been taken into account as a determinant of postural stability, while it could possibly specify subgroups of interest.

Methods

Postural stability was compared between 18 field hockey athletes who had recovered from an ankle sprain (mean (SD); 3.6 (1.5) months post-injury), and 16 uninjured controls. Force plate and kinematics parameters were calculated during single-leg standing: mean center of pressure speed, mean absolute horizontal ground reaction force, mean absolute ankle angular velocity, and mean absolute hip angular velocity. Additionally, cluster analysis was applied to the ‘injured’ participants, and the cluster with diminished postural stability was compared to the other participants with respect to ankle sprain history.

Findings

MANCOVA showed no significant difference between groups in postural stability (P = 0.68). A self-reported history of an (partial) ankle ligament rupture was typically present in the cluster with diminished postural stability. Subsequently, a ‘preceding rupture’ was added as a factor in the MANCOVA, which showed a significant association between diminished postural stability and a ‘preceding rupture’ (P = 0.01), for all four individual parameters (P: 0.001–0.029; Cohen's d: 0.96–2.23).

Interpretation

Diminished postural stability is not apparent in all previously injured athletes. However, our analysis suggests that an (mild) ankle sprain with a preceding severe ankle sprain is associated with impaired balance ability. Therefore, sensorimotor training may be emphasized in this particular group and caution is warranted in return to play decisions.     

A three-dimensional kinematic and kinetic comparison of overground and treadmill walking in healthy elderly subjects

Background

Instrumented treadmills offer a number of advantages for the biomechanical analysis of elderly gait, yet it is unclear how closely treadmill gait approximates overground gait. Although studies have indicated that the kinematics and kinetics of overground and treadmill gait are very similar in young adults, it still needs to be determined whether data collected in elderly adults during treadmill walking can be generalized to overground gait. The purpose of this study, therefore, was to compare the three-dimensional kinematics and kinetics of treadmill gait to overground gait in a group of healthy elderly subjects.

Methods

Three-dimensional kinematic and kinetic data for 18 healthy, nondisabled elderly subjects, age 65–81 years, were collected for speed-matched overground and treadmill walking conditions.

Findings

Overall, the kinematics and kinetics of gait during treadmill and overground walking in the elderly had very similar patterns. However, during treadmill walking elderly subjects showed greater cadence, smaller stride length and stride time as well as reductions in the majority of joint angles, moments and powers when compared to overground walking.

Interpretation

The large increase in cadence suggests that an effective method of acclimation to treadmill walking still needs to be determined. Because of the differences, we believe that in order for instrumented treadmills to become a suitable tool for research and training purposes in healthy elderly, subjects must be adequately acclimated to the treadmill.     

The effect of isolated gastrocnemius contracture and gastrocnemius recession on lower extremity kinematics and kinetics during stance

Background

Isolated gastrocnemius contracture limits ankle dorsiflexion with full knee extension and is potentially problematic during mid-stance of gait when 10° of dorsiflexion and full knee extension are needed. It is during this time that patients with isolated gastrocnemius contracture may demonstrate altered kinematics and/or kinetics. When conservative management fails to resolve painful foot pathologies associated with non-spastic isolated gastrocnemius contracture, gastrocnemius recession surgery has been suggested to resolve contracture and improve function and strength. However, there are no published reports on lower extremity kinematics/kinetics in the non-spastic isolated gastrocnemius contracture population. Assessment of alterations in gait mechanics is necessary to examine the effects of this potential surgical intervention.

Methods

Lower extremity kinematics and kinetics were assessed in 6 patients clinically diagnosed with isolated gastrocnemius contracture pre- and post-surgical recession compared with 33 healthy control participants.

Findings

Pre-operatively, patients with isolated gastrocnemius contracture demonstrated significantly increased peak knee flexion angles and knee flexion moments during mid-stance. There were no differences in peak ankle dorsiflexion angle or peak plantar flexion moment. Gastrocnemius recession did not alter gait kinematics/kinetics following surgery. Joint kinematic strategies utilized to compensate for isolated gastrocnemius contracture varied minimally between participants with IGC; most employed a flexed knee strategy, while one participant utilized a reduced ankle dorsiflexion strategy.

Interpretation

Select post-surgical gait mechanics were unaltered; however, gait mechanics were not similar between non-spastic isolated gastrocnemius contracture patients and healthy control participants. Surgical intervention for patients with isolated gastrocnemius contracture does not appear to create any negative gait adaptations; however, patients may benefit from gait retraining post-recession as maladaptive gait patterns persist post operatively.     

Gender differences in lower extremity gait biomechanics during walking using an unstable shoe

Background

In recent years several unstable shoe designs that cause increased instability at the ankle joint have been developed with the aims of training static and dynamic posture and postural control. However, earlier research found significant gender differences in the generation of ankle torque and in the reaction times after a perturbation. Therefore it is possible that men and women are affected differently by the instability that unstable shoes create. The purpose of this study was to investigate if gender differences exist a) during bilateral quiet stance or b) in lower extremity gait kinematics and kinetics when using unstable shoes.

Methods

Seventeen females and seventeen males were included in this study. Masai Barefoot Technology® shoes were used as test shoes. Center of pressure excursion was recorded during 30 s bilateral quiet stance trials using a force plate. Joint angles, resultant joint moments and joint moment impulses during walking were determined using standard gait analysis methods.

Findings

In bipedal stance, female subjects had significantly greater anterior–posterior center of pressure excursion than male subjects. In the stance phase of the gait cycle gender differences were found in the ankle joint moments which had not been reported in earlier studies using barefoot or normal shoe conditions.

Interpretation

The results suggest that women and men use different strategies to control the ankle joint when standing or walking in unstable shoes. Gender effects should therefore be taken into consideration if functional or therapeutic effects of unstable shoes are assessed.     

Impact of age and obstacle negotiation on timing measures of gait initiation

Introduction

The separate and combined impacts of age and walkway obstruction on reaction time, anticipatory postural adjustment phases of gait initiation and cognitive dual task performance are not well understood. This study aimed to a) examine the impact of age and task complexity on reaction and anticipatory postural adjustment phases separately b) examine the impact of age and walkway obstruction on cognitive task performance while walking.

Ankle range of motion is key to gait efficiency in adolescents with cerebral palsy

Background

Gait in young people with cerebral palsy is inefficient and there is a lack of relevant indicators for monitoring the problem. In particular, the impact of gait kinematics on gait efficiency is not well documented. The aim of this study is to examine the relationship between gait efficiency, gait kinematics, lower limb muscle strength, and muscular spasticity in adolescents with cerebral palsy.

Methods

Ten ambulatory adolescents with spastic cerebral palsy were recruited. The energy expenditure index during gait, gait kinematics, flexion and extension knee isometric muscle strength, and quadriceps spasticity were assessed.

Findings

Energy expenditure index (1.5 (0.7) beats/m) was strongly correlated with the ankle and knee flexion/extension ranges of motion (r = −0.82, P < 0.01 and r = −0.70, P < 0.02, respectively) and also with maximal plantar flexion (r = 0.74, P < 0.05) during gait. Knee flexion strength was the only strength measurement correlated with energy expenditure index (r = −0.85; P < 0.01).

Interpretation

This study suggests that ankle and knee flexion/extension ranges of motion during gait are key kinematics factors in gait efficiency in adolescents with cerebral palsy.