Dynamic Longitudinal Evaluation of the Utility of the Berg Balance Scale in Individuals With Motor Incomplete Spinal Cord Injury

Clinical Static Balance Assessment: A Narrative Review of Traditional and IMU-Based Posturography in Older Adults and Individuals with Incomplete Spinal Cord Injury

Maintaining a stable upright posture is essential for performing activities of daily living, and impaired standing balance may impact an individual's quality of life. Therefore, accurate and sensitive methods for assessing static balance are crucial for identifying balance impairments, understanding the underlying mechanisms of the balance deficiencies, and developing targeted interventions to improve standing balance and prevent falls. This review paper first explores the methods to quantify standing balance. Then, it reviews traditional posturography and recent advancements in using wearable inertial measurement units (IMUs) to assess static balance in two populations: older adults and those with incomplete spinal cord injury (iSCI). The inclusion of these two groups is supported by their large representation among individuals with balance impairments. Also, each group exhibits distinct aspects in balance assessment due to diverse underlying causes associated with aging and neurological impairment. Given the high vulnerability of both demographics to balance impairments and falls, the significance of targeted interventions to improve standing balance and mitigate fall risk becomes apparent. Overall, this review highlights the importance of static balance assessment and the potential of emerging methods and technologies to improve our understanding of postural control in different populations.

Quantifying balance control after spinal cord injury: Reliability and validity of the mini-BESTest

Context/Objective: Incomplete spinal cord injury (iSCI) causes deficits in balance control. The Mini-Balance Evaluation Systems Test (mini-BESTest) is a comprehensive measure; however, further testing of its psychometric properties among the iSCI population is needed. We evaluated the mini-BESTest's test-retest reliability, and concurrent and convergent validity among individuals living with iSCI for more than one year. Design: Cross-sectional study. Setting: Rehabilitation hospital. Participants: Twenty-one individuals with chronic motor iSCI (14 females, mean age 56.8 ± 14.0 years). Interventions: None. Outcome Measures: Participants completed the mini-BESTest at two sessions spaced two weeks apart. At the second session, participants performed tests of lower extremity muscle strength and quiet standing on a force platform with eyes opened (EO) and eyes closed (EC). Intraclass correlation coefficients (ICC) evaluated test-retest reliability. To evaluate concurrent and convergent validity, Pearson's correlation coefficient (r) quantified relationships between mini-BESTest scores and measures of center of pressure (COP) velocity during EO and EC standing, and lower extremity muscle strength, respectively. Results: Test-retest reliability of the mini-BESTest total score and sub-scale scores were high (ICC = 0.94-0.98). Mini-BESTest scores were inversely correlated with COP velocity when standing with EO (r = 0.54-0.71, P < 0.05), but not with EC. Lower extremity strength correlated strongly with mini-BESTest total scores (r = 0.73, P < 0.001). Conclusion: The mini-BESTest has high test-retest reliability, and concurrent and convergent validity in individuals with chronic iSCI.

Reliability and minimal detectable change of the mini-BESTest in adults with spinal cord injury in a rehabilitation setting

Background: The mini-Balance Evaluation Systems Test (mini-BESTest) is a valid tool for assessing standing balance in people with spinal cord injury (SCI). Its reliability has not yet been investigated with this population. Objective: To assess the test-retest and inter-rater reliability of the mini-BESTest in adults with SCI in a rehabilitation setting. Methods: Twenty-three participants admitted in a rehabilitation center following an SCI (mean age = 52.2 years, SD = 14.5; 13/23 tetraplegia; 14/23 traumatic injury) and able to stand 30 seconds without help were recruited. They were evaluated twice with the mini-BESTest to establish the test-retest reliability (interval of 1 to 2 days). One of the two sessions was video-recorded to establish the inter-rater reliability (3 physiotherapists). Intraclass correlation coefficients (ICC_2,1), weighted kappa (K_w) and Kendall's W were used to determine reliability of total score and individual items. Minimal detectable changes (MDC) were computed. Results. The mini-BESTest total scores showed excellent test-retest (ICC = 0.94) and inter-rater (ICC = 0.96) reliability. Reliability of 50% of the individual items was acceptable to excellent (Κ_w and W = 0.35-1.00). The MDC of the mini-BESTest total score was 4 points. Conclusion: The mini-BESTest is a reliable tool to assess standing balance in adults with an SCI. A minimal change of 4 points on the total scale is needed to be confident that the change is not a measurement error between two sessions or two raters.

Current state of balance assessment during transferring, sitting, standing and walking activities for the spinal cord injured population: A systematic review

CONTEXT

Comprehensive balance measures with high clinical utility and sound psychometric properties are needed to inform the rehabilitation of individuals with spinal cord injury (SCI).

OBJECTIVE

To identify the balance measures used in the SCI population, and to evaluate their clinical utility, psychometric properties and comprehensiveness.

METHODS

Medline, PubMed, Embase, Scopus, Web of Science, and the Allied and Complementary Medicine Database were searched from the earliest record to October 19/16. Two researchers independently screened abstracts for articles including a balance measure and adults with SCI. Extracted data included participant characteristics and descriptions of balance measures. Quality was evaluated by considering study design, sampling method and adequacy of description of research participants. Clinical utility of all balance measures was evaluated. Comprehensiveness was evaluated using the modified Systems Framework for Postural Control.

RESULTS

2820 abstracts were returned and 127 articles included. Thirty-one balance measures were identified; 11 evaluated a biomechanical construct and 20 were balance scales. All balance scales had high clinical utility. The Berg Balance Scale and Functional Reach Test were valid and reliable, while the mini-BESTest was the most comprehensive.

CONCLUSION

No single measure had high clinical utility, strong psychometric properties and comprehensiveness. The mini-BESTest and/or Activity-based Balance Level Evaluation may fill this gap with further testing of their psychometric properties.

Using data from the Microsoft Kinect 2 to determine postural stability in healthy subjects: A feasibility trial

The objective of this study was to determine whether kinematic data collected by the Microsoft Kinect 2 (MK2) could be used to quantify postural stability in healthy subjects. Twelve subjects were recruited for the project, and were instructed to perform a sequence of simple postural stability tasks. The movement sequence was performed as subjects were seated on top of a force platform, and the MK2 was positioned in front of them. This sequence of tasks was performed by each subject under three different postural conditions: "both feet on the ground" (1), "One foot off the ground" (2), and "both feet off the ground" (3). We compared force platform and MK2 data to quantify the degree to which the MK2 was returning reliable data across subjects. We then applied a novel machine-learning paradigm to the MK2 data in order to determine the extent to which data from the MK2 could be used to reliably classify different postural conditions. Our initial comparison of force plate and MK2 data showed a strong agreement between the two devices, with strong Pearson correlations between the trunk centroids "Spine_Mid" (0.85 ± 0.06), "Neck" (0.86 ± 0.07) and "Head" (0.87 ± 0.07), and the center of pressure centroid inferred by the force platform. Mean accuracy for the machine learning classifier from MK2 was 97.0%, with a specific classification accuracy breakdown of 90.9%, 100%, and 100% for conditions 1 through 3, respectively. Mean accuracy for the machine learning classifier derived from the force platform data was lower at 84.4%. We conclude that data from the MK2 has sufficient information content to allow us to classify sequences of tasks being performed under different levels of postural stability. Future studies will focus on validating this protocol on large populations of individuals with actual balance impairments in order to create a toolkit that is clinically validated and available to the medical community.

Assessment of Functional Improvement without Compensation for Human Spinal Cord Injury: Extending the Neuromuscular Recovery Scale to the Upper Extremities

The Neuromuscular Recovery Scale (NRS) is a tool for measuring functional recovery in spinal cord injured (SCI) persons based on tasks that test pre-injury functional capability. The NRS has been shown to be a valid, reliable, and responsive instrument for measuring functional recovery. The NRS has been updated to include three items measuring upper extremity function, and a new scoring mechanism has been defined. The purpose of this prospective, observational study was to explore the properties of the expanded NRS, introduce and evaluate the new scoring method, and to examine the score's relationship with other SCI outcome measures. The NRS and seven other SCI outcome measures were assessed at enrollment and after every 20 locomotor training sessions in 64 participants of the NeuroRecovery Network (NRN) of the Christopher and Dana Reeve Foundation (CDRF). The NRS exhibited a dominant first principal component that correlated strongly with the new NRS score, as well as a potential secondary component discriminating upper extremity function. The new NRS score and its empirical subscales were generally well-correlated with International Standards for the Neurological Classification of Spinal Cord Injury (ISNCSCI) motor scores and other established SCI functional measures, but exhibited substantial variability at their boundary values. The NRS score was more strongly correlated with other SCI functional measures than ISNCSCI motor scores were. The new NRS score was most responsive to change brought on by locomotor training. The expanded NRS appears to be a valuable tool in measuring functional recovery from SCI; further evaluation of its psychometric properties is warranted.

Retrospective assessment of the validity and use of the community balance and mobility scale among individuals with subacute spinal cord injury

STUDY DESIGN

This is a retrospective chart review.

OBJECTIVES

The objective of this study was to evaluate the convergent validity, internal consistency and use of the Community Balance & Mobility Scale (CB&M) in individuals with incomplete spinal cord injury (iSCI) during inpatient rehabilitation.

SETTING

This study was conducted in an SCI rehabilitation center in Canada.

METHODS

Inpatient charts from January 2009 to October 2015 were screened. A chart was excluded if the inpatient was aged >65 years, did not complete a CB&M and/or had a comorbid condition. Demographics, CB&M score and injury-related characteristics were extracted. Berg Balance Scale (BBS), Six-Minute Walk Test (6 MWT) and Ten-Meter Walk Test (10 mWT) scores were obtained if completed within 1 week of the CB&M. χ²-Tests were used to identify CB&M items that were uniformly distributed, implying good discrimination between individuals. Convergent validity was assessed by correlating (Pearson's r) CB&M scores with BBS, 6 MWT and 10 mWT scores. Internal consistency (Cronbach's α) was evaluated.

RESULTS

Thirty inpatients were included (23 male, 38.3±15.3 years old, three AIS C, 26 AIS D, C1-L4, 16 traumatic). BBS scores were ⩾51/56; however, CB&M scores showed a wider range (27-82/96). Unilateral Stance, Tandem Walking, Lateral Foot Scooting, Forward to Backward Walking and Descending Stairs showed uniform distributions. Scores on the CB&M correlated strongly with scores on the 6 MWT (r=0.72, P<0.001) and moderately strongly with 10 mWT and BBS scores (r=0.47-0.59, P=0.004-0.013). Cronbach's α=0.87.

CONCLUSIONS

The CB&M is a valid measure in high-functioning individuals with iSCI. Prospective studies are required to further evaluate the psychometric properties of the CB&M as a measure of high-level balance for SCI.

Locomotor training: as a treatment of spinal cord injury and in the progression of neurologic rehabilitation

Scientists, clinicians, administrators, individuals with spinal cord injury (SCI), and caregivers seek a common goal: to improve the outlook and general expectations of the adults and children living with neurologic injury. Important strides have already been accomplished; in fact, some have labeled the changes in neurologic rehabilitation a "paradigm shift." Not only do we recognize the potential of the damaged nervous system, but we also see that "recovery" can and should be valued and defined broadly. Quality-of-life measures and the individual's sense of accomplishment and well-being are now considered important factors. The ongoing challenge from research to clinical translation is the fine line between scientific uncertainty (ie, the tenet that nothing is ever proven) and the necessary burden of proof required by the clinical community. We review the current state of a specific SCI rehabilitation intervention (locomotor training), which has been shown to be efficacious although thoroughly debated, and summarize the findings from a multicenter collaboration, the Christopher and Dana Reeve Foundation's NeuroRecovery Network.