Can transverse plane rotations be estimated from video tape gait analysis?

Usability and Reliability of the Edinburgh Visual Gait Score in Children with Spastic Cerebral Palsy Using Smartphone Slow-Motion Video Technology and a Motion Analysis Application: A Pilot Study

BACKGROUND

The Edinburgh Visual Gait Score (EVGS) is a comprehensive measure of gait abnormalities in children with cerebral palsy (CP) and has good psychometric properties. However, it is cumbersome to administer and requires multiple devices to record and measure its various components. We conducted this study to determine if a smartphone video protocol could be used to improve the usability and reliability of the EVGS for daily use in a clinic setting.

METHODS

We used a handheld smartphone camera with slow-motion video technology and a motion analysis application to record and measure the EVGS of 30 ambulatory children with spastic CP. We tested the inter- and intra-rater reliability of various components of the EVGS between two observers.

RESULTS

Average age was 7 years 3 months (range 4-14 years). The mean (range) EVGS scores for the trunk, pelvis, hip, knee, ankle, and foot were 1.18 (0-3), 0.68 (0-3), 1.1 (0-4), 3.95 (1.5-7.5), 1.87 (0-4) and 4.13 (2-6.5) respectively. Total score was 12.92 (7-21.5). The mean (SD) scores for Gross Motor Function Classification System (GMFCS) levels II and III were 10.73 (3.86) and 14.96 (4.2) (p < 0.001). The intra-observer and inter-observer reliability using percentage of complete agreement was 65-98.3% and 61.7-92.5% respectively, with kappa values ranging from 0.15 to 0.87. Reliability was more for distal limb segments as compared to proximal segments.

CONCLUSION

We have described a simple and reliable method for quantitative OGA of children with CP, using smartphone video technology and motion analysis application, which can be performed by every clinician in an office setting.

LEVEL OF EVIDENCE

Level III.

Quantitative Assessment of Knee Progression Angle During Gait in Children With Cerebral Palsy

BACKGROUND

Abnormal hip rotation is a common deviation in children with cerebral palsy (CP). Clinicians typically assess hip rotation during gait by observing the direction that the patella points relative to the path of walking, which is referred to as the knee progression angle (KPA). Two kinematic methods for calculating the KPA are compared with each other. Video-based qualitative assessment of KPA is compared with the quantitative methods to determine reliability and validity.

METHODS

The KPA was calculated by both direct and indirect methods for 32 typically developing (TD) children and a convenience cohort of 43 children with hemiplegic type CP. An additional convenience cohort of 26 children with hemiplegic type CP was selected for qualitative assessment of KPA, performed by 3 experienced clinicians, using 3 categories (internal, >10 degrees; neutral, -10 to 10 degrees; and external, >-10 degrees).

RESULTS

Root mean square (RMS) analysis comparing the direct and indirect KPAs was 1.14+0.43 degrees for TD children, and 1.75+1.54 degrees for the affected side of children with CP. The difference in RMS among the 2 groups was statistically, but not clinically, significant (P=0.019). Intraclass correlation coefficient revealed excellent agreement between the direct and indirect methods of KPA for TD and CP children (0.996 and 0.992, respectively; P<0.001).For the qualitative assessment of KPA there was complete agreement among all examiners for 17 of 26 cases (65%). Direct KPA matched for 49 of 78 observations (63%) and indirect KPA matched for 52 of 78 observations (67%).

CONCLUSIONS

The RMS analysis of direct and indirect methods for KPA was statistically but not clinically significant, which supports the use of either method based upon availability. Video-based qualitative assessment of KPA showed moderate reliability and validity. The differences between observed and calculated KPA indicate the need for caution when relying on visual assessments for clinical interpretation, and demonstrate the value of adding KPA calculation to standard kinematic analysis.

LEVEL OF EVIDENCE

Level II-diagnostic test.

CORRELATION BETWEEN VISUAL GAIT ANALYSIS AND FUNCTIONAL ASPECTS IN CEREBRAL PALSY

Objective:

To verify the correlation between visual gait analysis (VGA) by the Edinburgh visual gait score (EVGS) and functional aspects using the Timed Up and Go Test (TUG) and Gross Motor Function Classification System (GMFCS) in individuals with cerebral palsy (CP).

Methods:

Retrospective cross sectional study of 35 patients with CP. The mean age 12.61 years old, 94.3% were spastic; 34.4% hemiplegic, 54.3% diplegic, 11.4% triplegic; 45.7% were level II GMFCS, 42.9% level I, 5.7% level III and 5.7% level IV. VGA was analyzed by the Edinburgh visual gait score (EVGS), functional mobility was assessed by TUG and functionality through GMFCS. The Spearman correlation was used for statistical analysis.

Results:

The mean EVGS score was 18.97. The mean TUG was 13.71sec. EVGS showed moderate correlation with TUG (r=0.46, p=0.03) and GMFCS (r=0.45, p=0.00).

Conclusion:

Worse VGA scores correlate to worse functionality and mobility performance. Due to the observed correlation, it is possible to assert that VGA is a useful tool on evaluation of CP patients. Level of Evidence III, Retrospective Comparative Study.

Use of videographic examination for analysis of efficacy of botulinum toxin in the lower limbs in children with cerebral palsy

The objective of this study was to test the interobserver and intraobserver reproducibility of videographic gait analysis in paediatric cerebral palsy patients following botulinum toxin type-A injections. Standardized videos according to gait-specific functional criteria were assessed for 1 h. For intraobserver reproducibility, 13 of 17 items showed good/moderate correlation, one mediocre and three poor correlation. For interobserver reproducibility, 12 of 17 items showed excellent, good or moderate agreement, five items showed poor agreement. Overall, 9 of 17 items showed good intraobserver or interobserver reproducibility. Mean interobserver scores for sagittal plane items were slightly lower than mean intraobserver scores (kappa=0.509 and 0.536, respectively). In conclusion, video analysis of children with cerebral palsy based on functional criteria is useful.

The status of gait assessment among physiotherapists in the United Kingdom11No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors(s) or upon any organization with which the author(s) is/are associated

OBJECTIVES

To evaluate how physiotherapists are trained in and use clinically orientated gait assessment tools and instrumented gait analysis, and to identify if a need exists for a standardized methodology.

DESIGN

Survey.

SETTING

UK National Health Service.

PARTICIPANTS

Physiotherapists working with a variety of patient groups in 210 randomly selected Health Care Trusts.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Amount of gait assessment training, frequency of gait laboratory use, types and frequency of standardized gait assessment tools used, and expressed need for a gait assessment tool in clinical practice.

RESULTS

A total of 1826 (43.5%) physiotherapists responded. Management of abnormal gait constituted a major aspect of physiotherapy practice; yet, there was no systematic use of standardized gait assessment tools. Gait video images were typically collected and analyzed without the use of standardized protocols. Only 23.1% of all respondents had a patient assessed in a gait laboratory. Clinicians indicated that they need training in gait assessment (66.4%) and desire guidance at a national level. Exactly 91.8% of physiotherapists requested a new gait assessment tool that can be used easily and quickly within a busy schedule without compromising reliability and validity.

CONCLUSIONS

Gait assessment plays a pivotal role for physiotherapists managing gait problems. The challenge for developers of gait assessment tools is to find a balance between the practicalities of use and scientific merit.

Edinburgh visual gait score for use in cerebral palsy

Complex gait analysis systems are not generally available worldwide, and no simple system of assessing gait by observation has been validated specifically for use in patients with cerebral palsy. The authors have developed a visual gait analysis score for use in cerebral palsy. Videotaped sequences of patients were recorded before and after surgery as part of a three-dimensional gait study using a Vicon (Oxford, U.K.) gait analysis system. The score demonstrated good intraobserver and interobserver reliability. The numeric values of the score elements correlated well with the measurements obtained from instrumented gait analysis for the same patients, and the score was able to detect postoperative change.