脑卒中患者步行能力与下肢三维运动学及动力学相关性分析

目的:通过对脑卒中偏瘫患者下肢三维运动学和动力学的分析,寻找偏瘫患者步态特点,比较分析步行能力与运动学和动力学之间的关系,从运动力学角度探讨偏瘫患者异常步行的原因,寻找康复治疗中需解决的关键问题。方法:选择首次脑卒中后可以独立步行10m以上的右侧偏瘫患者20例为实验组,正常健康中老年人16例为对照组。采用Vicon和AMTOR6-7进行三维步态运动学和动力学检测和分析。结果:实验组与正常对照组比较,脑卒中患者与健康中老年人在步频、跨步时间、双腿支撑时间、步时、离地比率、步长、跨步长和步速同侧比较差异有显著性意义(P<0.05),患侧离地占步态周期百分比和健侧单腿支撑时间实验组与对照组比较差异有显著性意义(P<0.05)。矢状面上同侧髋关节伸展角度、膝关节屈曲角度和踝关节背伸及跖屈角度比较差异都有显著性意义(P<0.05)。同侧髋关节屈伸力矩、同侧膝关节伸直力矩和患侧踝关节背伸力矩实验组和对照组相比差异有显著性意义(P<0.05),步行能力(步速)与患侧髋关节伸展、健侧膝关节屈曲、双侧膝关节伸展、双侧踝关节背伸和跖屈角度相关,均有显著性意义(P<0.05);同时也和双侧髋关节屈伸、膝关节伸展和踝关节背伸力矩相关(P<0.01)。结论:①步长是脑卒中偏瘫患者步态异常的重要参考指数;②髋关节和膝关节伸展,踝关节背伸和跖屈是步态异常的重要表现;③下肢髋关节和膝关节屈伸肌群和踝关节背伸肌群的力量是影响步行能力的重要因素。     

Compensatory advantages of toe walking

OBJECTIVES: The study's hypothesis is that toe walking requires less peak muscle strength distally about the ankle and knee compared with normal heel-toe walking and thus may have compensatory advantages for patients with upper motor neuron injury and distal muscle weakness. DESIGN: Motion analysis and force platform data were collected in able-bodied subjects during toe walking and normal walking. Sagittal plane joint torques reflecting muscle force requirements and joint powers reflecting nonisometric muscle contraction were compared between the two conditions using paired t tests, applying a Bonferroni correction for multiple comparisons. SETTING: A gait laboratory. SUBJECTS: Seventeen able-bodied adults, 9 of whom were ballet dancers. MAIN OUTCOME MEASURES: Peak hip, knee, and ankle joint torque and power variables during walking. RESULTS: Peak ankle plantarflexor torque and ankle power generation during terminal stance and preswing were reduced (p<.001), as compared with normal heel-toe walking. The normal ankle dorsiflexor torque at initial contact-and the knee extensor torque and knee power generation during loading response were all essentially absent during toe walking. Hip extensor torque and hip power generation during the loading response phase were greater for toe walking (p<.001). CONCLUSION: Toe walking may require less ankle plantarflexor, ankle dorsiflexor, and knee extensor strength than normal heel-toe walking and thus may have compensatory advantages for patients with upper motor neuron injury and distal lower extremity weakness.     

Hip hiking and circumduction: quantitative definitions

OBJECTIVE: To define and propose clinically useful quantitative measurements of hip hiking and circumduction using standard three-dimensional motion analysis techniques. DESIGN: We studied pelvic, hip, and thigh motions in 23 subjects with hemiparetic, stiff-legged gait as a result of stroke and compared these motions with those obtained from 23 able-bodied controls. RESULTS: We observed significantly increased hip abduction on the unaffected limb during stance, with simultaneous elevation of the affected side of the pelvis during swing. We define these differences as hip hiking and, thus, can quantify the degree to which hip hiking occurs by measuring the unaffected coronal hip angle and/or the coronal pelvic angle when the affected limb is in midswing. We also observed a greater than normal coronal thigh angle during midswing of the affected limb that we can use to quantitatively define circumduction. Of note, hip abduction during swing was not increased on the affected swing limb, compared with the control. CONCLUSIONS: Hip hiking can be defined precisely as unaffected coronal hip and/or pelvic angle when the affected limb is in midswing and circumduction can be defined as greater than normal coronal thigh angle during midswing of the affected limb. These precise definitions should allow us to better communicate and understand the implications of these gait patterns, and can serve as the basis for clinically meaningful quantitative assessment and outcome measurement tools.     

The impact of hearing loss on three-dimensional lower limb joint torques during walking in prepubertal boys

IntroductionIn children, the impact of hearing loss on biomechanical gait parameters is not well understood. Thus, the objectives of this study were to examine three-dimensional lower limb joint torques in deaf compared to age-matched healthy (hearing) children while walking at preferred gait speed.MethodsThirty prepubertal boys aged 8–14 were enrolled in this study and divided into a group with hearing loss (deaf group) and an age-matched healthy control. Three-dimensional joint torques were analyzed during barefoot walking at preferred speed using Kistler force plates and a Vicon motion capture system.ResultsFindings revealed that boys with hearing loss showed lower joint torques in ankle evertors, knee flexors, abductors and internal rotators as well as in hip internal rotators in both, the dominant and non-dominant lower limbs (all p < 0.05; d = 1.23–7.00; 14–79%). Further, in the dominant limb, larger peak ankle dorsiflexor (p < 0.001; d = 1.83; 129%), knee adductor (p < 0.001; d = 3.20; 800%), and hip adductor torques (p < 0.001; d = 2.62; 350%) were found in deaf participants compared with controls.ConclusionThe observed altered lower limb torques during walking are indicative of unstable gait in children with hearing loss. More research is needed to elucidate whether physical training (e.g., balance and/or gait training) has the potential to improve walking performance in this patient group.     

Can toe-walking contribute to stiff-legged gait?

OBJECTIVE: Spastic paretic stiff-legged gait, defined as reduced knee flexion in swing, has previously been attributed solely to spastic quadriceps activity. In earlier work, the authors suggested that reduced knee flexion in swing can be attributed to other indirect factors, such as poor hip flexion and abnormal foot-ankle function during gait. The present study was undertaken to determine whether toe-walking, which often occurs in conjunction with stiff-legged gait, in and of itself, might explain some of the reduced knee flexion in swing. DESIGN: An analysis was performed of three-dimensional kinematic data collected from able-bodied subjects while walking on their toes vs. normal heel-toe walking. RESULTS: Peak knee flexion was reduced significantly compared with normal heel-toe walking (42.2+/-8.9 degrees toe-walking vs. 59.2+/-5.7 degrees heel-toe walking; P < 0.00001). CONCLUSIONS: This finding, which occurred when controlling for walking speed, may be clinically relevant for patients who have both a toe-walking and a stiff-legged gait pattern. Some of the reduced knee flexion in swing may be merely a consequence of toe-walking, rather than a result of other causes, such as intrinsic spasticity or abnormal muscle firing about the knee.     

Spastic paretic stiff-legged gait: joint kinetics

OBJECTIVE: The authors previously suggested that spastic paretic stiff-legged gait, defined as reduced knee flexion in swing associated with upper-motor neuron injury, can be attributed to multiple impairments besides spastic quadriceps activity. This study hypothesizes that subjects with spastic paretic stiff-legged gait have altered kinetics not only about the knee but also about the hip and ankle. DESIGN: Joint kinetic data of 20 subjects with spastic paretic stiff-legged gait caused by stroke were compared with data obtained from 20 able-bodied subjects. RESULTS: Significant reductions in the subject group were found in both peak knee-joint power absorption (0.42+/-0.34 vs. 0.99+/-0.27 W/(kg x m x m/sec)) and peak ankle-joint power generation (0.74+/-0.42 vs. 1.51+/-0.17 W/(kg x m x m/sec); both P < 0.0001). The authors observed increases in peak external-hip flexion torque in stance, hip-power generation in loading response, knee-extension torque in midstance, ankle-dorsiflexion torque, and ankle-power absorption in stance. There was substantial variability in most torque and power values among subjects, which was significantly greater than that observed in the control subjects. CONCLUSIONS: These findings, in conjunction with previous studies, support the likelihood of multiple mechanisms for reduced knee flexion in swing. Alternatively, some of the joint kinetic differences could be compensations for or associated with reduced knee flexion in swing. The substantial variability among subjects implies that despite a similar visual appearance of reduced knee flexion among subjects with a spastic paretic stiff-legged gait pattern, each individual has unique mechanisms associated with this observed gait pattern.     

Walking characteristics of runners with a transfemoral or knee-disarticulation prosthesis

BackgroundRunning with prostheses has become a common activity for amputees participating in sports and recreation. However, very few studies have characterized the kinematic and kinetic parameters of walking in individuals with amputation who are runners. Thus, this study attempts to elucidate the kinematics and kinetics of walking in runners with a unilateral transfemoral amputation or knee-disarticulation.MethodsThis study experimentally compares the prosthetic and intact limbs of runners with prostheses as well as compares the findings against the limbs of age-matched able-bodied individuals while walking. Fourteen runners with a unilateral transfemoral amputation or knee-disarticulation were recruited and 14 age-matched able-bodied individuals were prepared using gait database. Spatiotemporal, kinematic, and kinetic parameters of walking were analyzed using a 3-demensional motion capture system.ResultsThe results showed that the peak ankle positive power at pre-swing and peak hip positive power from loading response to mid stance in the intact limb were significantly larger than that in the prosthetic limb. Moreover, to compensate for missing anatomical functions on the prosthetic limb, it appeared that the intact limb of the runners generated larger peak joint power by producing more ankle plantarflexor and hip extensor moments while walking.InterpretationThis study demonstrated that the runners rely on their intact limb while walking. Training of hip extensor muscles of the intact limb may be beneficial for these individuals.     

Increased power generation in impaired lower extremities correlated with changes in walking speeds in sub-acute stroke patients

Background

Establishing changes in net joint power in the lower extremity of patients during recovery of walking might direct gait training in early stroke rehabilitation. It is hypothesized that (1) net joint power in the lower extremity joints would increase in sub-acute stroke patients following gait rehabilitation, and (2) the improvements in net joint power would be significantly correlated with changes in walking speed.

Methods

Thirteen sub-acute patients (<3 months from stroke onset) participated in the study. All patients completed 6 weeks of gait training (3 weeks of robotic gait training and 3 weeks of physiotherapy). The gait patterns were analyzed using 3D motion analysis before and after training. The assessed variables were; gait speed and the net peak joint power of the ankle plantar flexors, hip extensors, hip flexors, hip abductors, and knee extensors.

Findings

Ankle plantar flexor power in the impaired limb and hip extensor power in the unimpaired limb increased significantly following training (133% and 77%, respectively; P < 0.002). Improvements (from 20% to 133%) in net joint power of the ankle plantar flexors, hip extensors, hip flexors, and hip abductors of the impaired limb and ankle plantar flexors and hip abductors of the unimpaired limb significantly correlated with the recovery of walking speed following training (0.24 m/s to 0.51 m/s) (r = 0.71–0.86).

Interpretation

The findings suggested investigations for strengthening the plantar flexors, hip flexors, hip extensors, and hip abductors concentrically, and knee extensors eccentrically in the impaired limb to determine the effectiveness in improving gait performance.     

Gait evaluation of an automatic stance-control knee orthosis in a patient with postpoliomyelitis

OBJECTIVE: To determine gait differences in a subject ambulating with a knee-ankle-foot orthosis (KAFO) with a locked knee joint versus an automatic stance-control knee joint. DESIGN: Single-subject crossover design. SETTING: Tertiary rehabilitation facility with a motion analysis laboratory. PARTICIPANT: A 61-year-old ambulatory male volunteer with postpoliomyelitis walking with a stance-control KAFO. INTERVENTIONS: Instrumented gait analysis and Physiological Cost Index in the locked knee and stance-control modes. MAIN OUTCOME MEASURE: Differences in gait parameters. RESULTS: On the braced limb, stance-control mode showed a near-normal knee flexion wave in swing, reduced pelvic retraction and rotational excursion, and improved hip power generation. On the nonbraced limb, the stance-control mode allowed elimination of vaulting, reduction in abnormal ankle and hip power generation, increased knee power absorption, and more typical quadriceps activation. There was a trend toward improved energy efficiency in the stance-control mode. CONCLUSIONS: Use of a stance-control knee joint in a KAFO appears to improve gait biomechanics and improve energy efficiency compared with a locked knee.     

Effects of walking with loads above the ankle on gait parameters of persons with hemiparesis after stroke

Background

Walking with a load at the ankle during gait training is a simple way to resist lower limb movements to induce functional muscle strengthening. This study investigated the effects of walking with different loads attached above the paretic ankle on biomechanical gait parameters during over ground walking in post-stroke participants.

Methods

Ten participants with moderate chronic hemiparesis were evaluated while walking over ground with three different loads (0.5, 1.0, and 1.5 kg) attached above the paretic ankle. Gait speed, cadence, step lengths as well as hip and knee angular displacements, joint moments and power of the paretic limb were compared while walking with and without loads.

Findings

Walking with a load led to an increased in gait speed (+ 0.03–0.05 m/s), and in step length of the paretic leg (+ 5.6 to 9.4% step length, effect size = 0.49–0.63), but not of the non-paretic leg. The proportion of the stance and swing phases did not change. Maximal joint moments (+ 20 to 48%, effect size = 0.26–0.55) and power (+ 20 to 114%, effect size = 0.30–0.57) increases varied across participants but were mostly affected in early stance at the hip and during the late swing phase at the knee. Mean angular displacement changes were less than 4°.

Interpretation

Post-stroke participants are able to increase hip and knee power bursts to meet the increased mechanical demand of added loads attached to the paretic ankle, while preserving the basic pattern of walking. Further study is needed before using loading to functionally strengthen paretic muscles.     

Examining outcomes from total knee arthroplasty and the relationship between quadriceps strength and knee function over time

BACKGROUND: Temporal-spatial gait parameters improve following total knee arthroplasty (TKA) but lower limb kinematics and moments fail to match those of age-matched healthy individuals. The aim of this study was to determine whether quadriceps strength, clinical measures of knee function, lower limb kinematics, and joint moments improve following arthroplasty and normalize over time. METHODS: Twelve patients underwent total knee arthroplasty were tested at 3 and 12 months following surgery. Twelve matched controls were also tested. All underwent quadriceps strength testing and gait analysis to calculate knee joint kinematics and kinetics. Function was assessed using clinical tests and self-report. FINDINGS: All clinical measures except for quadriceps strength significantly improved from 3 to 12 months. Gait asymmetry was observed at 3 months (lower stance times, peak knee flexion angle, range of motion and vertical ground reaction force), but ankle, knee and hip moments contributing to the total limb support moment were equivalent between legs. At 12 months, gait speed remained significantly slower than controls. Inter-limb differences in peak knee flexion angle and range of motion persisted. Greater hip and lower knee moments were evident in the operated limb, compared to the non-operated limb and controls. Quadriceps strength was positively correlated with faster times on the Time Up and Go and Stair Climbing Test and greater distances during the 6 Minute Walk test. INTERPRETATION: Patients who have undergone TKA demonstrate improvements in function as measured by self-report and functional performance measures. Gait becomes more symmetric and quadriceps strength becomes stronger. Some approached the values of healthy control subjects. Important differences still remain however. The larger hip extensor contribution to the total support moment may be to compensate for the diminished knee extensor contribution during level walking. Since instrumented gait analysis and functional performance measures appear to reflect different aspects of recovery following total knee replacement, both should be considered when evaluating gait and function.     

Differences in hip–knee joint coupling during gait after anterior cruciate ligament reconstruction

BackgroundAfter anterior cruciate ligament injury, patients have increased risk for developing degenerative osteoarthritis, potentially due to the kinematic changes that persist after surgical reconstruction. Current research only describes single joint kinematic differences rather than the way in which two joints behave concurrently, termed joint coupling. The purpose of this study was to compare knee motion relative to hip motion in anterior cruciate ligament reconstructed and healthy limbs during walking and jogging.MethodsThirty-seven recreationally active volunteers (22 reconstructed, 15 healthy) walked and jogged at 4.83 km/h and 9.66 km/h respectively. Vector coding methods were used to calculate stride-to-stride variability, magnitude, and vector angle of 6 joint couples during walking and jogging: hip frontal–knee frontal planes, hip frontal–knee sagittal, hip frontal–knee transverse, hip sagittal–knee frontal, hip sagittal–knee transverse, and hip transverse–knee frontal planes.FindingsThe hip sagittal–knee frontal and hip sagittal–knee transverse joint couples had decreased variability during mid-stance, and all other couples had increased variability during the stance phase in the reconstructed group. The reconstructed group had decreased magnitude of joint excursion in the hip frontal–knee sagittal couple during all phases of gait during walking. Vector angles of the hip frontal–knee transverse couple increased in the reconstructed group during the loading, middle, and terminal stance phases, and swing phase of gait during walking.InterpretationThe increased variability and decreased magnitude of joint excursion indicate that movement patterns were less consistent during walking gait despite employing a more constrained system during movement in the reconstructed limb compared to healthy controls.     

Gait performance with compensatory adaptations in stroke patients with different degrees of motor recovery

OBJECTIVE: Gait patterns vary among stroke patients. This study attempted to discover gait performance with compensatory adaptations in stroke patients with different degrees of motor recovery. DESIGN: Data were gathered from 35 stroke patients and 15 healthy subjects. Gait performance and motor recovery were assessed 6 mos after stroke. Stroke patients further were divided into poor and good groups. The walking velocity was correlated with Brunnstr?m's stages, and the temporal stride and motion variables of the two groups were compared. RESULTS: Walking velocity was positively correlated with the Brunnstr?m's stages of the proximal lower limb. The poor group displayed slower walking velocity and shorter single-support time compared with the good group. Both groups displayed low maximum excursion of hip extension and ankle plantarflexion during the stance phase and low maximum excursion of hip and knee flexion and ankle dorsiflexion during the swing phase. Moreover, both groups displayed excessive pelvic tilts during the stance and swing phases. However, the poor group displayed different pelvic motion and timing sequences to each peak joint angle from normal subjects and the good group. Peak hip and knee angles of the affected limb during the stance phase occurred almost simultaneously in this group. CONCLUSIONS: Selective control of the proximal lower limb may be the main determinant of walking velocity. The compensatory adaptations were similar, except for pelvic motion, in stroke patients with different levels of motor recovery, whereas the poor group walked with synergistic mass patterns and reduced stability.     

A study of the gait characteristics of patients with chronic osteoarthritis of the knee

Purpose : There is scant information at present on the effects of severe osteoarthritis (OA) of the knee joint on gait. In the present study the kinematic and kinetic parameters of gait and the pattern of activation of four lower limb muscles were examined during walking at a self-selected pace on level ground. The spatiotemporal parameters of gait were also computed. Methods : Measurements were made using a three-dimensional optico-electronic motion analysis system integrated with a force plate and telemetered electromyography. Results : Fifty-eight patients with severe OA of the knee and 25 age-matched healthy control subjects were examined. Patients demonstrated a significantly reduced walking speed, shorter stride length and a more prolonged stance phase of the gait cycle compared with the control subjects. They also had less range of motion at the hip, knee and ankle, joints and generated less moments and powers at the ankle and more moments at the knee than the control group. The differences were statistically significant for all parameters except the degree of ankle plantar flexion in stance. Activation of the rectus femoris muscle was prolonged in the patients group. Conclusions : It is concluded that the observed gait abnormalities were due to instability of the knee joint in stance. This may have important clinical implications for the rehabilitation of patients with severe OA of the knee.     

Hemiplegic gait of stroke patients: the effect of using a cane.

OBJECTIVE: To assess the effects of cane use on the hemiplegic gait of stroke patients, focusing on the temporal, spatial, and kinematic variables. DESIGN: Case-control study comparing the effect of walking with and without a cane using a six-camera computerized motion analysis system. SETTING: Stroke clinic of a tertiary care hospital. PARTICIPANTS: Fifteen ambulatory stroke patients were analyzed, including 10 men and 5 women (mean age, 56.9 years; mean time since stroke, 9.8 weeks). Nine age-matched healthy elderly subjects were recruited as a control group. RESULTS: Stroke patients walking with a cane showed significantly increased stride period, stride length, and affected side step length, as well as decreased cadence and step width (p < .05) in comparison with those who walked without a cane. There were no significant differences in the gait phases and the five gait events of hemiplegic gait walking with or without a cane. Cane use thus may have more effect on spatial variables than on temporal variables. The affected-side kinematics of hemiplegic gait with a cane showed increased pelvic obliquity, hip abduction, and ankle eversion during terminal stance phase; increased hip extension, knee extension, and ankle plantar-flexion during preswing phase; and increased hip adduction, knee flexion, and ankle dorsiflexion during swing phase as compared with hemiplegic gait without a cane. A cane thus improved the hemiplegic gait by assisting the affected limb to smoothly shift the center of body mass toward the sound limb and to enhance push off during preswing phase. It also improved circumduction gait during swing phase. CONCLUSION: Stroke patients walking with a cane demonstrated more normal spatial variables and joint motion than did those without a cane.     

脑卒中偏瘫患者膝过伸步态与下肢肌肉激活功能的相关性

目的 观察脑卒中膝过伸患者步行时膝关节过伸角度与下肢各关节运动学参数及下肢主要肌肉激活情况的相关性。方法 2020年8月至2021年9月,在同济大学附属养志康复医院选择伴膝过伸的脑卒中患者24例,以及性别、年龄、身高及体质量匹配并伴膝过伸的健康人24例,采用三维运动捕捉系统和无线表面肌电采集系统进行分析,记录骨盆、髋、膝、踝关节在矢状面上的角度,以及双侧臀大肌、股二头肌、股内侧肌、腓肠肌内侧头肌电数据。结果 脑卒中患者单腿支撑相的最大膝过伸角度时,各关节角度和各肌肉激活度均与健康人有非常显著性差异(|t|> 3.080, P <0.01)。脑卒中患者单腿支撑相的最大膝过伸角度与臀大肌激活度明显负相关(r=-0.532,P <0.01);两组膝过伸最大角度与踝跖屈角度呈显著正相关(r> 0.686, P <0.001)。结论 脑卒中患者膝过伸步态的矫正不仅需要关注膝关节控制,还需要关注踝关节控制和臀肌功能。     

The effect of functional knee brace design and hinge misalignment on lower limb joint mechanics

BACKGROUND: Knee bracing has been shown to alter lower limb joint mechanics, which may protect the anterior cruciate ligament. The effect of brace alignment and brace type, however, remains largely unknown. This study was conducted to determine whether the use of a functional knee brace, the type of brace used or its alignment relative to the knee causes biomechanical alterations to gait. METHODS: Ten healthy participants took part in two walking conditions (aligned brace and misaligned brace) for two different types of brace (sleeve brace with bilateral hinges and hinge-post-shell). A non-braced condition was included as a baseline measure. Three-dimensional kinematics and force platform data were used to calculate the joint intersegmental forces and net joint moments of the ankle, knee and hip. FINDINGS: In comparison to non-braced walking, the shell brace in its aligned position significantly reduced the peak ankle plantarflexor moment. There was a decreased peak knee flexion angle with both the aligned shell and sleeve braces. The shell brace in its aligned position significantly increased peak knee adduction and reduced peak knee internal rotation. INTERPRETATION: In this sample of healthy participants, functional knee bracing failed to alter lower limb mechanics in such a way that would reduce the force transmitted to the anterior cruciate ligament. In addition, although there were brace induced changes in lower limb kinematics with 2cm of distal hinge misalignment, it is unlikely that hinge misalignment of this magnitude is detrimental to an uninjured knee joint during walking.     

A study of the gait characteristics of patients with chronic osteoarthritis of the knee

Purpose : There is scant information at present on the effects of severe osteoarthritis (OA) of the knee joint on gait. In the present study the kinematic and kinetic parameters of gait and the pattern of activation of four lower limb muscles were examined during walking at a self-selected pace on level ground. The spatiotemporal parameters of gait were also computed.

Methods : Measurements were made using a three-dimensional optico-electronic motion analysis system integrated with a force plate and telemetered electromyography.

Results : Fifty-eight patients with severe OA of the knee and 25 age-matched healthy control subjects were examined. Patients demonstrated a significantly reduced walking speed, shorter stride length and a more prolonged stance phase of the gait cycle compared with the control subjects. They also had less range of motion at the hip, knee and ankle, joints and generated less moments and powers at the ankle and more moments at the knee than the control group. The differences were statistically significant for all parameters except the degree of ankle plantar flexion in stance. Activation of the rectus femoris muscle was prolonged in the patients group.

Conclusions : It is concluded that the observed gait abnormalities were due to instability of the knee joint in stance. This may have important clinical implications for the rehabilitation of patients with severe OA of the knee.     

单侧小腿截肢患者穿假肢后的步态运动学参数研究

目的 采用计算机辅助康复环境(CAREN)步态评估系统分析单侧小腿截肢患者穿假肢后的步态运动学参数,并分析其产生差异的原因。 方法 选取单侧小腿中段截肢但均装配假肢的受试者9例设为假肢组,同期选择健全受试者11例设为标准组,通过CAREN步态评估系统对2组受试者的步态运动学参数进行收集、处理、分析,并根据分析报告阐明产生差异原因。 结果 假肢组步态时相性指数为(0.88±0.04),其假肢侧的步长、支撑期百分比、髋关节支撑期最大伸展角度、膝关节支撑期最大屈曲角度、踝关节足跟着地背屈角度、踝关节支撑期最大背屈角度、踝关节支撑期最大跖屈角度与健侧比较,差异均有统计学意义(P<0.05）。假肢组假肢侧的步行速度、步态周期、跨步长、支撑期百分比、髋关节足跟落地屈髋角度、髋关节支撑期最大伸展角度、髋关节支撑期最大屈曲角度、膝关节足跟着地屈膝角度、踝关节足跟着地背屈角度、踝关节支撑期最大跖屈角度、踝关节支撑期最大背屈角度与标准组双侧均值比较,差异均有统计学意义(P<0.05）。 结论 单侧小腿截肢者穿戴假肢后步态时相对称性为（0.88±0.04）,假肢侧踝关节运动学参数显著弱于自身健侧,其时空与运动学参数也显著弱于健全人。     

The effect of total knee replacement on dynamic support of the body during walking and stair ascent

BACKGROUND: Little is known about the effects of total knee replacement surgery on the contributions of individual joint moments to the total support moment. A better understanding of these effects may enhance rehabilitation protocols and determine factors related to long-term surgical outcome. METHOD: Twenty-one subjects with total knee replacement and 21 controls performed level walking and stair ascent at two testing periods, pre- and 6 months post-surgery. Variables studied included gait velocity, stride length, knee flexion angle, net joint moments of the hip, knee and ankle, and total support moment. Data were analyzed at the first peak vertical ground reaction force. FINDINGS: For level walking, the total support moment, knee extensor moment, and knee flexion angle of total knee replacement patients were less than controls at post-surgery. For stair ascent, the patient group total support moment, ankle plantarflexor moment, and knee flexion angle were less than controls at both testing periods, while knee extensor moment was less than controls at post-surgery. Extensor synergies of the total knee replacement patients revealed less knee and more hip contributions during level walking and larger hip contributions during stair ascent to the total support moment than controls at both testing periods. INTERPRETATION: A feature of total knee replacement gait, pre- and post-surgery, is a stiff knee attitude which may serve to protect the quadriceps. The larger hip extensor contribution to the total support moment observed in the patients may compensate for the diminished knee extensor contribution during level walking and stair ascent.