Effect of compensation procedures for velocity on repeatability and variability of gait parameters in normal subjects

Reliability of three-dimensional kinematic gait data in adults with spinal cord injury

Objectives

Three-dimensional gait analysis has been recommended as part of standardized gait assessment in people with spinal cord injury. The aim was to investigate inter- and intra-session reliabilities of gait kinematics in people with spinal cord injury.

Methods

Fifteen adults with spinal cord injury performed two test sessions on separate days. Six infrared cameras, 16 reflective markers and the Plug-in gait model were used. For each subject, five gait trials from both sessions were included. The Gait Profile Score and the Gait Variable Score were used as kinematic outcome measures. Reliability was assessed with intraclass correlation coefficient, standard error of measurement, minimal detectable change, and Bland-Altman plots.

Results

Inter-session intraclass correlation coefficient for all variables was >0.82 and standard error of measurement <1.8°, except for hip rotation. Intra-session reliability was found to be high (≥0.78) and slightly better than that for inter-session. Minimal detectable change for all variables was <4.7°, except for hip rotation.

Conclusions

The high inter- and intra-session reliabilities indicate small intrinsic variation of gait. Thus, three-dimensional gait analysis seems to be a reliable tool to evaluate kinematic gait in adults with spinal cord injury, but caution is warranted especially for hip rotation evaluation.

Variability of kinetic variables during gait in unilateral transtibial amputees

BACKGROUND

Prosthetic gait increases demands on stability. Some variability measures can be used to investigate the stability of movement for prosthetic feet.

OBJECTIVES

The purpose of this study was to determine the influence of the prosthetic foot on ground reaction force variability for transtibial amputee gait.

STUDY DESIGN

Comparative analysis.

METHODS

Eleven male unilateral transtibial amputees participated in this study. Each subject walked at self-selected speed with both conventional (SACH) and energy storing (Sureflex) feet. Time and ground reaction force variables and their coefficients of variation were calculated for each foot type and limb.

RESULTS

Mediolateral force variables had high variability for all conditions. The Sureflex had a larger variability than the SACH foot for the braking peak (p < 0.05), which may have been caused by gait instability after the heel strike. There were significant differences between intact and prosthetic limbs in total loading (force impulses) with the SACH foot (p < 0.05).

CONCLUSIONS

The prosthetic foot and alignment issues related to the foot influence GRF variability. During the braking phase the SACH foot is characterized by higher variability in mediolateral direction and Sureflex by higher variability in anterior-posterior direction.

CLINICAL RELEVANCE

Differences in variability in ground reaction force variables can represent a person's stability. Observing variability can contribute to better understanding of critical events in gait cycle with the use of various prosthetic feet.

Subjects with hip osteoarthritis show distinctive patterns of trunk movements during gait-a body-fixed-sensor based analysis

Background

Compensatory trunk movements during gait, such as a Duchenne limp, are observed frequently in subjects with osteoarthritis of the hip, yet angular trunk movements are seldom included in clinical gait assessments. Hence, the objective of this study was to quantify compensatory trunk movements during gait in subjects with hip osteoarthritis, outside a gait laboratory, using a body-fixed-sensor based gait analysis. Frontal plane angular movements of the pelvis and thorax and spatiotemporal parameters of persons who showed a Duchenne limp during gait were compared to healthy subjects and persons without a Duchenne limp.

Methods

A Body-fixed-sensor based gait analysis approach was used. Two body-fixed sensors were positioned at the dorsal side of the pelvis and on the upper thorax. Peak-to-peak frontal plane range of motion (ROM) and spatiotemporal parameters (walking speed, step length and cadence) of persons with a Duchenne limp during gait were compared to healthy subjects and persons without a Duchenne limp. Participants were instructed to walk at a self-selected low, preferred and high speed along a hospital corridor. Generalized estimating equations (GEE) analyses were used to assess group differences between persons with a Duchenne limp, without a Duchenne limp and healthy subjects.

Results

Persons with a Duchenne limp showed a significantly larger thoracic ROM during walking compared to healthy subjects and to persons without a Duchenne limp. In both groups of persons with hip osteoarthritis, pelvic ROM was lower than in healthy subjects. This difference however only reached significance in persons without a Duchenne limp. The ratio of thoracic ROM relative to pelvic ROM revealed distinct differences in trunk movement patterns. Persons with hip osteoarthritis walked at a significantly lower speed compared to healthy subjects. No differences in step length and cadence were found between patients and healthy subjects, after correction for differences in walking speed.

Conclusions

Distinctive patterns of frontal plane angular trunk movements during gait could be objectively quantified in healthy subjects and in persons with hip osteoarthritis using a body-fixed-sensor based gait analysis approach. Therefore, frontal plane angular trunk movements should be included in clinical gait assessments of persons with hip osteoarthritis.

Gait variability in older adults: a structured review of testing protocol and clinimetric properties

Gait variability (stride-to-stride fluctuations) is used increasingly as a marker for gait performance and future mobility status, cognitive status, and falls. This structured review explicitly examined literature that reported on the reliability, validity and responsiveness of gait variability in older adults. We searched Medline, Embase, Web of Science, Scopus, CINAHL, PEDRO, Biomechanics, SportDiscus and PsycInfo databases. Two independent reviewers undertook data extraction, with adjudication by a third reviewer in cases of disagreement. Twenty-two full papers were screened and 10 met the predefined inclusion criteria, involving 1036 participants who were mainly community dwelling older adults in their 8th decade. A wide range of gait variability parameters, testing protocols and calculations of gait variability were reported. Reliability estimates varied, but were mostly fair to moderate. Concurrent validity was established for stance time variability and change estimates were reported for stance time and swing time. Standard of reporting was generally poor, with insufficient detail provided for aspects of measurement and testing protocols. Further research is required to standardise testing procedures and establish reliability, responsiveness and validity for confident use of gait variability as a robust measure.

Assessment of the kinematic variability among 12 motion analysis laboratories

Variability of kinematic measurements among sites participating in a collaborative research investigation is a primary factor in determining number of subjects, level of detectable difference and statistical power of a multi-site research study. In this study, one subject was evaluated by 24 examiners at 12 motion analysis laboratories and the observed variability of nine kinematic parameters are reported. Following implementation of a standardized gait analysis protocol the same subject returned for another evaluation at each of the 12 laboratories. Additionally, system accuracy and variability of the subject within and between test days are included as factors that may affect between site variability. Marker placement among examiners is identified as the largest source of variability. A 20% decrease in variability was noted following implementation of the standardized protocol.

Quantitative gait analysis of patients with bilateral hip osteoarthritis excluding the influence of walking speed

BACKGROUND

The purpose of this study was to investigate gait characteristics of patients with bilateral hip osteoarthritis (BHO) independent of walking speed.

METHODS

We measured gait parameters in 12 BHO patients during free walking activities and in 12 normal adults during both free walking and slow walking activities using a three-dimensional computerized gait analysis system.

RESULTS

Patients with BHO had a lower walking speed, step length, and cadence than normal subjects during free walking. When compared with normal subjects walking at a slow speed, the walking speed difference among BHO patients disappeared, although BHO patients retained a relatively high cadence. Kinematic and kinetic factor analysis of BHO patients at free speed compared to normal subjects walking at a slow speed showed a forward-tilted pelvic angle in the BHO patients that dropped to that of the ipsilateral side during the stance phase. The peak extension and abduction angle of the hip and the peak abduction moment of the hip were all low, whereas the peak generation power of the ankle was high in BHO patients.

CONCLUSIONS

Gait characteristics of patients with BHO, independent of walking speed, were as follows: (1) increased cadence and ankle generation power; (2) reduced step width, hip extension, and abduction angle as well as a lower hip abduction moment; (3) maintained forward tilting of the pelvis during gait cycle; and (4) appearance of a dropped pelvis during the stance phase.

Effects of disease severity on response to lateral wedged shoe insole for medial compartment knee osteoarthritis

OBJECTIVE

To determine the effects of lateral wedged insoles on knee kinetics and kinematics during walking, according to radiographic severity of medial compartment knee osteoarthritis (OA).

DESIGN

A prospective case control study of patients with medial compartment OA of the knee.

SETTING

Gait analysis laboratory in a university hospital.

PARTICIPANTS

Forty-six medial compartment knees with OA of 23 patients with bilateral disease and 38 knees of 19 age-matched healthy subjects as controls.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

We measured the peak external adduction moment at the knee during the stance phase of gait and the first acceleration peak after heel strike at the lateral side of the femoral condyles. Kellgren and Lawrence grading system was used for radiographic assessment of OA severity.

RESULTS

The mean value of peak external adduction moment of the knee was higher in OA knees than the control. Application of lateral wedged insoles significantly reduced the peak external adduction moment in Kellgren-Lawrence grades I and II knee OA patients. The first acceleration peak value after heel strike in these patients was relatively high compared with the control. Application of lateral wedged insoles significantly reduced the first acceleration peak in Kellgren-Lawrence grades I and II knee OA patients.

CONCLUSIONS

The kinetic and kinematic effects of wearing of lateral wedged insoles were significant in Kellgren-Lawrence grades I and II knee OA. The results support the recommendation of use of lateral wedged insoles for patients with early and mild knee OA.