Percentage Of Stance Phase Research Articles

Robot-assisted gait training improves the walking ability of hemiplegic patients

Objective To evaluate the effect of robot-assisted gait training on the walking ability of hemiplegic patients. Methods Sixty hemiplegic patients were randomly divided into a control group and a treatment group, each of 30. Both groups were given traditional rehabilitation and drug therapy. The control group was additionally provided with the traditional gait training, while the treatment group additionally received robot-assisted gait training. The gait training lasted 30 minutes a day, 5 days per week. Before and after 8 weeks of training, the time parameters, phase parameters, the joint angles of the lower limbs, and the peak ground reaction forces of both groups were evaluated using a three-dimensional gait analysis system. Results After the intervention, the walking velocity, stride frequency and stride length had increased in the treatment group, while stride width had decreased. Significant improvement was observed in the treatment group in terms of the percentage of swing phase on the paretic side, the percentage of stance phase on the paretic side, the single support time ratio, the percentage of double support phase, the range of motion of the hip and knee joints, and the peak vertical and forward ground reaction force as a percentage of body weight. The improvements were significantly greater than those observed in the control group. Conclusions Compared with traditional walking training, robot-assisted gait training can be more effective in improving the walking ability of hemiplegic patients. Key words: Robots; Gait training; Walking ability; Gait analysis

WalkAide Efficacy on Gait and Energy Expenditure in Children with Hemiplegic Cerebral Palsy

The aim of this study was to investigate the effects of WalkAide functional electrical stimulation on gait pattern and energy expenditure in children with hemiplegic cerebral palsy. Seventeen children were assigned to the study group, whose members received functional electrical stimulation (pulse width, 300 μs; frequency, 33 Hz, 2 hours/d, 3 days/week for 3 consecutive months). Seventeen other children were assigned to the control group, whose members participated in a conventional physical therapy exercise program for 3 successive months. Baseline and posttreatment assessments were performed using the GAITRite system to evaluate gait parameters and using an open-circuit indirect calorimeter to evaluate energy expenditure. Children in the study group showed a significant improvement when compared with those in the control group (P < 0.005). The gait parameters (stride length, cadence, speed, cycle time, and stance phase percentage) after treatment were (0.74 m,119 steps/min, 0.75 m/s, 0.65 s, 55.9%) and (0.5 m,125 steps/min, 0.6 m/s, 0.49 s, 50.4%) for the study group and control group, respectively. The mean energy expenditures after treatment were 8.18 ± 0.88 and 9.16 ± 0.65 mL/kg per minute for the study and control groups, respectively. WalkAide functional electrical stimulation may be a useful tool for improving gait pattern and energy expenditure in children with hemiplegic cerebral palsy. Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES:: Upon completion of this article, the reader should be able to: (1) Identify gait abnormalities in children with hemiplegic CP; (2) Describe the impact of utilizing the WalkAide on energy expenditure during gait training in children with hemiplegic CP; and (3) Describe the benefits of including the WalkAide in the treatment of gait abnormalities in children with hemiplegic CP. Advanced : The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The Association of Academic Physiatrists designates this activity for a maximum of 1.5 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

A Surgical Model of Posttraumatic Osteoarthritis With Histological and Gait Validation.

Background:Posttraumatic osteoarthritis (PTOA) is secondary to an array of joint injuries. Animal models are useful tools for addressing the uniqueness of PTOA progression in each type of joint injury and developing strategies for PTOA prevention and treatment.Hypothesis:Intra-articular fracture induces PTOA pathology.Study Design:Descriptive laboratory study.Methods:Through a parapatellar incision, the medial tibial plateau was exposed in the left knees of 8 Sprague-Dawley rats. Osteotomy at the midpoint between the tibial crest and the outermost portion of the medial tibial plateau, including the covering articular cartilage, was performed using a surgical blade. The fractured medial tibial plateau was fixed with 2 needles transversely. The fractured knees were not immobilized. Before and after surgery, rat gait was recorded. Rats were sacrificed at week 8, and their knees were harvested for histology.Results:After intra-articular fracture, the affected limbs altered gait from baseline (week 0). In the first 2 weeks, the gait of the operated limbs featured a reduced paw print intensity and stride length but increased maximal contact and stance time. Reduction of maximal and mean print area and duty cycle (the percentage of stance phase in a step) was present from week 1 to week 5. Only print length was reduced in weeks 7 and 8. At week 8, histology of the operated knees demonstrated osteoarthritic pathology. The severity of the PTOA pathology did not correlate with the changes of print length at week 8.Conclusion:Intra-articular fracture of the medial tibial plateau effectively induced PTOA in rat knees. During PTOA development, the injured limbs demonstrated characteristic gait.Clinical Relevance:Intra-articular fracture represents severe joint injury and associates with a high rate of PTOA. This animal model, with histologic and gait validations, can be useful for future studies of PTOA prevention and early diagnosis.

Blindfolded Balance Training in Patients with Parkinson's Disease: A Sensory-Motor Strategy to Improve the Gait.

Aim. Recent evidence suggested that the use of treadmill training may improve gait parameters. Visual deprivation could engage alternative sensory strategies to control dynamic equilibrium and stabilize gait based on vestibulospinal reflexes (VSR). We aimed to investigate the efficacy of a blindfolded balance training (BBT) in the improvement of stride phase percentage reliable gait parameters in patients with Parkinson's Disease (PD) compared to patients treated with standard physical therapy (PT). Methods. Thirty PD patients were randomized in two groups of 15 patients, one group treated with BBT during two weeks and another group treated with standard PT during eight weeks. We evaluated gait parameters before and after BBT and PT interventions, in terms of double stance, swing, and stance phase percentage. Results. BBT induced an improvement of double stance phase as revealed (decreased percentage of double stance phase during the gait cycle) in comparison to PT. The other gait parameters swing and stance phase did not differ between the two groups. Discussion. These results support the introduction of complementary rehabilitative strategies based on sensory-motor stimulation in the traditional PD patient's rehabilitation. Further studies are needed to investigate the neurophysiological circuits and mechanism underlying clinical and motor modifications.

A comparison of variability in spatiotemporal gait parameters between treadmill and overground walking conditions

Motorized treadmills are commonly used in biomechanical and clinical studies of human walking. Whether treadmill walking induces identical motor responses to overground walking, however, is equivocal. The purpose of this study was to examine differences in the spatiotemporal gait parameters of the lower extremities and trunk during treadmill and overground walking using comparison of mean and variability values. Twenty healthy participants (age 23.8±1.2 years) walked for 6min on a treadmill and overground while wearing APDM 6 Opal inertial monitors. Stride length, stride time, stride velocity, cadence, stance phase percentage, and peak sagittal and frontal plane trunk velocities were measured. Mean values were calculated for each parameter as well as estimates of short- (SD1) and long-term variability (SD2) using Poincaré analyses. The mean, SD1, and SD2 values were compared between overground and treadmill walking conditions with paired t-tests (α=0.05) and with effect size estimates using Cohen's d statistic. Mean values for each of the gait parameters were statistically equivalent between treadmill and overground walking (p>0.05). The SD1 and SD2 values representing short- and long-term variability were considerably reduced (p<0.05) on the treadmill as compared to overground walking. This demonstrates the importance of consideration of gait variability when using treadmills for research or clinical purposes. Treadmill training may induce invariant gait patterns, posing difficulty in translating locomotor skills gained on a treadmill to overground walking conditions.

The influence of a powered knee-ankle-foot orthosis on walking in poliomyelitis subjects: A pilot study.

Traditionally, the anatomical knee joint is locked in extension when walking with a conventional knee-ankle-foot orthosis. A powered knee-ankle-foot orthosis was developed to provide restriction of knee flexion during stance phase and active flexion and extension of the knee during swing phase of gait. The purpose of this study was to determine differences of the powered knee-ankle-foot orthosis compared to a locked knee-ankle-foot orthosis in kinematic data and temporospatial parameters during ambulation. Quasi-experimental design. Subjects with poliomyelitis (n = 7) volunteered for this study and undertook gait analysis with both the powered and the conventional knee-ankle-foot orthoses. Three trials per orthosis were collected while each subject walked along a 6-m walkway using a calibrated six-camera three-dimensional video-based motion analysis system. Walking with the powered knee-ankle-foot orthosis resulted in a significant reduction in both walking speed and step length (both 18%), but a significant increase in stance phase percentage compared to walking with the conventional knee-ankle-foot orthosis. Cadence was not significantly different between the two test conditions (p = 0.751). There was significantly higher knee flexion during swing phase and increased hip hiking when using the powered orthosis. The new powered orthosis permitted improved knee joint kinematic for knee-ankle-foot orthosis users while providing knee support in stance and active knee motion in swing in the gait cycle. Therefore, the new powered orthosis provided more natural knee flexion during swing for orthosis users compared to the locked knee-ankle-foot orthosis. This orthosis has the potential to improve knee joint kinematics and gait pattern in poliomyelitis subjects during walking activities.

Effect of extracorporeal shock wave therapy on gait pattern in hemiplegic cerebral palsy: a randomized controlled trial.

The aim of this study was to investigate the effects of shock wave therapy on gait pattern in children with hemiplegic cerebral palsy. Fifteen children were assigned to the study group, whose members received shock wave therapy (1500 shots/muscle, frequency of 5Hz, energy of 0.030 mJ/mm, one session/wk). Another 15 were assigned to the control group, whose members participated in a conventional physical therapy exercise program for 3 successive months. Baseline and posttreatment assessments were performed using the Modified Ashworth Scale to evaluate spasticity degrees and using a three-dimensional gait analysis to evaluate gait parameters. Children in the study group showed a significant improvement when compared with those in the control group (P < 0.005). The Modified Ashworth scores after treatment were 1.86 (0.22) and 1.63 (0.23) for the control and study groups, respectively. The gait parameters (stride length, cadence, speed, cycle time, and stance phase percentage) after treatment were 0.5 m, 125 steps/min, 0.6 m/sec, 0.48 sec, and 50.4% and 0.74 m, 119 steps/min, 0.75 m/sec, 0.65 sec, and 55.9% for the control group and the study group, respectively. Shock wave therapy may be a useful tool for improving spasticity and gait pattern in children with hemiplegic cerebral palsy.

Comparison of the International Committee of the Red Cross Foot With the Solid Ankle Cushion Heel Foot During Gait: A Randomized Double-Blind Study

ObjectiveTo compare the well-recognized solid ankle cushion heel (SACH) foot with the prosthetic foot developed by the International Committee of the Red Cross (CR Equipements SACH) during gait. DesignDouble-blind study was conducted to compare the influence on the biomechanics of gait of the CR Equipements SACH foot and the SACH foot. SettingUniversity hospital research center. ParticipantsParticipants with unilateral transtibial amputation (N=15) were included. InterventionsThree-dimensional motion analysis system and 2 forceplates were used to capture body motion and ground reaction forces during gait at a self-selected speed and at 1.2m/s. Main Outcome MeasuresNonparametric Wilcoxon matched-pairs tests were used to compare the 2 prosthetic feet with respect to their spatiotemporal (gait velocity, stride length, and percentage of stance phase), kinematic (range and peak angles of the pelvis, hip, knee, and ankle), and kinetic (peak moment and power of the hip, knee, and ankle) parameters. ResultsCompared with the SACH foot, the CR Equipements SACH foot demonstrated a significantly greater stance phase symmetry ratio (SACH: 94% vs CR Equipements SACH: 97%), a more extensive ankle range of motion in the sagittal plane (SACH: 7° vs CR Equipements SACH: 12°), a greater maximal dorsiflexion angle during the terminal stance phase (SACH: 10° vs CR Equipements SACH: 13°), and a higher ankle power (SACH: .31W/kg vs CR Equipements SACH: .40W/kg). No significant difference was found for the examined knee, hip, and pelvis parameters. ConclusionsThe CR Equipements SACH foot provides more symmetry and improves ankle kinematics and kinetics in the sagittal plane compared with the SACH foot. This study suggests that individuals using the CR Equipements SACH foot improve their gait biomechanics compared when using the SACH foot.

Kinetic and Kinematic Evaluation of the Ankle Joint After Achilles Tendon Reconstruction With Free Semitendinosus Tendon Graft: Preliminary Results

Chronic rupture of the Achilles tendon (AT) is a surgical challenge and has effects on the gait. The purpose of this study was to evaluate the kinetic and kinematic parameters of the ankle joint in patients with AT rupture operated using a free semitendinosus tendon graft. Thirteen patients were analyzed 6 and 12 months after surgery in a force platform, while the movements were recorded by six infrared cameras. The kinematic variables analyzed included speed, cadence, step length, percentage of stance phase, and range of movement (ROM) of the ankle joint in the sagittal and frontal planes. Kinetic data were obtained by joint movement in different phases of the gait cycle. Functional assessment was performed using the American Orthopaedic Foot and Ankle Society (AOFAS) score. The patients showed a significant increase (P = 0.0215) in AOFAS from 68.5 (±18.7) to 85.2 (±18.0). Speed, cadence, and length of step of the four groups (1A, 1B, 2A, 2B) were lower than the control group (group 3), and the percentage in stance phase was higher for the nonoperated foot 6-month group (1B) compared to the control group (group 3). For the kinematic data, the ROM of the ankle in stance phase increased from 6 to 12 months showing an effect of time between four groups (1A, 1B, 2A, 2B). During swing phase, the ankle ROM was lower in the operated side (effect of side, P = 0.0255) and groups 1A and 2A demonstrated statistical differences when compared with the control group (group 3) (P = 0.0240 and P = 0.0414, respectively). ROM of inversion and eversion presented effect of time among the same groups (P = 0.0059) cited before. There were no differences in kinetic data between groups. This study showed close proximity between the control group and the operated group. Furthermore, improvement was shown when comparing the 6 and 12 months postsurgery periods. The surgical procedure is therefore helpful for the patient and few changes were present in gait and ankle biomechanics.

Comparison of different methods to extract the required coefficient of friction for level walking

The required coefficient of friction (RCOF) is an important predictor for slip incidents. Despite the wide use of the RCOF there is no standardised method for identifying the RCOF from ground reaction forces. This article presents a comparison of the outcomes from seven different methods, derived from those reported in the literature, for identifying the RCOF from the same data. While commonly used methods are based on a normal force threshold, percentage of stance phase or time from heel contact, a newly introduced hybrid method is based on a combination of normal force, time and direction of increase in coefficient of friction. Although no major differences were found with these methods in more than half the strikes, significant differences were found in a significant portion of strikes. Potential problems with some of these methods were identified and discussed and they appear to be overcome by the hybrid method. Practitioner Summary: No standard method exists for determining the required coefficient of friction (RCOF), an important predictor for slipping. In this study, RCOF values from a single data set, using various methods fromthe literature, differed considerably for a significant portion of strikes. A hybrid method may yield improved results.

Walking with Concurrent Cognitive Tasks in People with Traumatic Brain Injury

PURPOSE: To investigate the influence of concurrent cognitive tasks on gait performance in people with TBI. METHODS: A total of 9 people with TBI (age: 41.9 ± 10.6) and 9 healthy controls (42.8 ± 11.1) participated in this study. All were asked to complete 20-meter walking course while performing various types of concurrent cognitive tasks. Each participant was asked to walk at their maximum speed in 4 test conditions: a) simple walking (W), b) walking with word generation (WWG-walking and citing words starting with a randomly assigned alphabet letter), c) walking with answering questions (WQA - walking and answering questions based on personal information gathered in advance), and d) walking with performing visual tasks (WVT - walking and performing 3 visual tasks involving directional sign, shape and spatial recognition). All walking trials were captured by 3D motion analysis system (Vicon Nexus) for gait analysis. A Bluetooth headset was used for walking trials which involved any verbal communication. Repeated measures mix model ANOVA was used to examine any alterations in gait variables. RESULTS: Non-TBI group showed significant decreases in walking speed (10.84% and 10.24% decreases respectively) and stride length (6.96% and 6.33% decreases respectively) while performing WWG and WQA as compared to W (all ps <.05). TBI group demonstrated significant decreases in walking speed (30.77% decrease), stride length (18.12% decrease) and hip ROM (14.12% decrease) during WWG performance as compared to W while it showed an increase in stance phase percentage (7.91% increase) with WWG (all ps <.05). Only the affected limb changed kinematics of the hip joint significantly decreasing its excursion from 38.32 ± 13.28 degrees to 32.91±12.11 degrees (p<.031). Significant group interactions were found in walking speed, stride length and stance phase percentage, where TBI group showed greater changes in those gait variables CONCLUSIONS: People with TBI have more difficulty in performing multiple tasks involving cognitive functions while walking as compared to those without TBI. The findings suggest that the use of various configurations of walking and talking or other cognitive tasks can be more effective for improving functional gait of people with TBI rather than simple practice of walking.

The Influence of Applying Additional Weight to the Affected Leg on Gait Patterns During Aquatic Treadmill Walking in People Poststroke

Jung T, Lee D, Charalambous C, Vrongistinos K. The influence of applying additional weight to the affected leg on gait patterns during aquatic treadmill walking in people poststroke. Objective To investigate how the application of additional weights to the affected leg influences gait patterns of people poststroke during aquatic treadmill walking. Design Comparative gait analysis. Setting University-based aquatic therapy center. Participants Community-dwelling volunteers (n=22) with chronic hemiparesis caused by stroke. Interventions Not applicable. Main Outcome Measures Spatiotemporal and kinematic gait parameters. Results The use of an ankle weight showed an increase in the stance phase percentage of gait cycle (3%, P=.015) when compared with no weight. However, the difference was not significant after a Bonferroni adjustment was applied for a more stringent statistical analysis. No significant differences were found in cadence and stride length. The use of an ankle weight showed a significant decrease of the peak hip flexion (7.9%, P=.001) of the affected limb as compared with no weight condition. This decrease was marked as the reduction of unwanted limb flotation because people poststroke typically show excessive hip flexion of the paretic leg in the late swing phase followed by fluctuating hip movements during aquatic treadmill walking. The frontal and transverse plane hip motions did not show any significant differences but displayed a trend of a decrease in the peak hip abduction during the swing phase with additional weights. The use of additional weight did not alter sagittal plane kinematics of the knee and ankle joints. Conclusions The use of applied weight on the affected limb can reduce unwanted limb flotation on the paretic side during aquatic treadmill walking. It can also assist the stance stability by increasing the stance phase percentage closer to 60% of gait cycle. Both findings can contribute to the development of more efficient motor patterns in gait training for people poststroke. The use of a cuff weight does not seem to reduce the limb circumduction during aquatic treadmill walking.

PR_235: Effect of Nonarticulated Ankle-Foot Orthosis on Gait Pattern in Hemiplegic Subjects: A Randomized Crossover Study

Objective: To evaluate whether ankle-foot orthoses (AFOs) have a beneficial effect on gait pattern in subjects with stroke. Design: Randomized crossover study. Setting: Stroke orthotic clinic of a freestanding rehabilitation hospital. Participants: 40 subjects with stroke able to ambulate safely without orthosis. Interventions: Subjects were randomly selected to either first walk without and then with an AFO, or first walk with and then without an AFO. A 5.1×0.9m (17×3ft) mat recorded subjects’ movements and transmitted the information to a computer. Each subject performed three 10-m walks, with rest periods between each trial. Main Outcome Measures: Velocity, cadence, step-length, and time in stance phase. Results: The mean velocities without and with an AFO were 49.1 and 57.3 respectively (P<.001); the mean cadence without and with an AFO was 67.9 and 74.4, respectively (P<.001); the mean step-length difference without and with an AFO was 11.3 and 9.0, respectively (P<.05). Stance phase percentage of the gait cycle was significantly shorter on the orthotic side than the sound side (F=39.8, P<.001). Conclusions: Results indicate that AFO use significantly improves velocity, cadence, and step length in subjects with stroke.

The influence of walking speed on plantar pressure measurements using the two-step gait initiation protocol

Background: Plantar pressure measurement is being increasingly used in both research and clinical practice to measure the effects of various footwear and physical therapy interventions. However, the influence of walking speed on plantar pressure parameters has not been evaluated in detail, and may have an effect on study design and interpretation of results. Objective: To determine the effect of changes in walking speed on plantar pressure measurements obtained using the two-step gait initiation protocol. Methods: Plantar pressure parameters were measured with the EMED-SF system using the two-step gait initiation protocol in 20 healthy participants (10 males, 10 females) aged 20–37 (mean 27.5, S.D. 5.2 years) when walking at self-selected slow, normal and fast speeds. Results: With increased walking speeds, contact time increased at all regions under the foot. When expressed as a percentage of stance phase, contact time at the forefoot was not affected by walking speed; however, a smaller proportion of stance phase was spent loading the medial and lateral heel and lateral midfoot regions. Maximum force and peak pressure consistently increased at all regions at faster walking speeds, with the exception of the lateral midfoot, first MPJ and third–fifth MPJ regions. Force–time and pressure–time integrals were reduced at faster walking speeds, with the exception of loading under the toes, which remained relatively constant. Conclusions: Variations in walking speed from slow to fast significantly influence the timing and magnitude of plantar pressure values using the two-step gait initiation protocol. However, no significant differences are evident between self-selected slow and normal speeds for maximum force and peak pressure values. These findings suggest that when assessing the effects of various interventions on plantar pressure patterns, correcting for small changes in walking speed at slower speeds may not be critical for maximum force and peak pressure measurements, but is necessary for appropriate interpretation of force–time and pressure–time integrals at most regions of the plantar foot.

Effects of changes in cadence, prosthetic componentry, and time on interface pressures and shear stresses of three trans-tibial amputees

Objective. To evaluate the effects of changes in cadence, prosthetic componentry, and time on interface pressures and resultant shear stresses in trans-tibial amputee case studies. Design. Interface stresses were monitored using custom-designed instrumentation at 13 sites on three subjects with unilateral trans-tibial amputation walking with patellar-tendon-bearing prosthetic limbs. Background. Previous studies suggested that week-to-week residual limb changes altered interface stresses more than did alterations in prosthetic alignment. No studies investigating effects of changes in cadence or componentry on interface stress distributions nor comparing their influence with week-to-week changes have been conducted previously. Methods. Five different prosthetic componentry configurations were tested at each of three cadences in four sessions. Data were analysed for the magnitudes and timings of peak pressures and resultant shear stresses as well as corresponding resultant shear angles. Results. None of the three cadences or five componentry configurations consistently induced significantly ( P<0.05) higher or lower interface stress magnitudes for all subjects. However, an Aluminium Pylon/SACH Foot combination compared with an AirStance (pneumatic shank)/Seattle LightFoot unit induced later peak interface stress timings as a percentage of stance phase. Higher and more frequent interface stress changes were seen between the weekly sessions than between different cadences or between different componentry configurations. Conclusion. The amputees' capabilities to compensate for week-to-week residual limb changes were less than those for intra-session cadence or componentry alterations. Relevance Results suggest that effective techniques to accommodate week-to-week residual limb fluctuations could have a greater impact on maintaining consistent interface stress distributions than do adjustments in cadence or componentry.

Effects of high doses of oxytetracycline on metacarpophalangeal joint kinematics in neonatal foals

Summary Thirteen clinically normal Belgian-type foals were used to study the effects of high doses of Oxytetracycline on metacarpophalangeal joint kinematics. Seven foals (treatment group) received 2 doses of oxytetracycline (3 g, iv). The first dose was given when foals were 4 days old; the second dose was given 24 hours later. Six foals (control group) received 2 doses of saline (0.9% NaCl) solution (15 ml, iv) at equivalent time periods. All foals were videotaped at a walk twice: immediately prior to the first treatment and 24 hours after the second treatment. The tapes were digitized, and metacarpophalangeal joint angle was measured along the palmar surface of the limb during 3 strides. The angular data were normalized for time, and data from the 3 strides were averaged to describe a representative stride. Repeated measures anova was used to test for differences between groups and within groups over time. Values for stride duration, stance phase percentage, and minimum metacarpophalangeal joint angle obtained before treatment were not significantly different from values obtained after treatment. Maximum metacarpophalangeal joint angle, which occurred during the stance phase of the stride, and range of joint motion were significantly increased for foals in the treatment group, compared with foals in the control group.

The pattern of forefoot pressure distribution in hallux valgus

The pressure characteristics under the forefoot in a healthy asymptomatic population have been compared to those presenting with hallux valgus deformity. 90 dynamic footprints from 30 subjects have been recorded using the Musgrave Footprint System. The peak pressures, contact times (as a percentage of stance phase) and times to peak pressure have been analysed for each metatarsal head. The patterns of pressure distribution across the forefeet of the whole group have been classed into four groups subjectively and confirmed using cluster analysis. The medial pressure pattern occurred more frequently in the hallux valgus group. The mean hallux valgus forefoot had increased pressure medially with increased contact time and time to peak pressure.

Temporal, kinematic, and kinetic variables related to gait speed in subjects with hemiplegia: a regression approach.

The gait speed that a patient selects is a well-known indicator of overall gait performance. The purpose of this study was to use multiple linear regression to assess the strength of association of temporal, kinematic, and kinetic gait variables with high walking speeds in patients with hemiplegia. Thirty-two subjects (20 male, 12 female) with an average age of 61 years took part in a sagittal-plane gait study of both sides of the body. Data from cinematographic film and a force plate obtained during multiple walking trials were used in a seven-segment link-segment kinetic model of the walking subject to yield temporal, kinematic, and kinetic variables. Variables correlating significantly with self-selected speed included the maximum hip extension angle and the maximum hip flexion moment on the affected side, and the maximum ankle and hip powers on both sides. A stepwise regression identified variables most useful in predicting stride speed. For the affected side, these variables were the hip flexion moment, the ankle moment range, the knee moment range, and the proportion of double support. Together these variables explained 94% of the variation in gait speed. On the unaffected side, the variables were the percentage of stance phase, the maximum ankle power (push-off), and the maximum hip power (pull-off). They explained 92% of the variation in gait speed. These results suggest that experimental studies are needed to assess the effects of treatment aimed at increasing ankle power and hip power and at decreasing the stance time on the affected side, and that these studies should be directed at obtaining a larger hip flexion moment and a larger ankle moment range on the unaffected side.