Machine learning for automating subjective clinical assessment of gait impairment in people with acquired brain injury - a comparison of an image extraction and classification system to expert scoring.

BACKGROUND: Walking impairment is a common disability post acquired brain injury (ABI), with visually evident arm movement abnormality identified as negatively impacting a multitude of psychological factors. The International Classification of Functioning, Disability and Health (ICF) qualifiers scale has been used to subjectively assess arm movement abnormality, showing strong intra-rater and test-retest reliability, however, only moderate inter-rater reliability. This impacts clinical utility, limiting its use as a measurement tool. To both automate the analysis and overcome these errors, the primary aim of this study was to evaluate the ability of a novel two-level machine learning model to assess arm movement abnormality during walking in people with ABI. METHODS: Frontal plane gait videos were used to train four networks with 50%, 75%, 90%, and 100% of participants (ABI: n = 42, healthy controls: n = 34) to automatically identify anatomical landmarks using DeepLabCut™ and calculate two-dimensional kinematic joint angles. Assessment scores from three experienced neurorehabilitation clinicians were used with these joint angles to train random forest networks with nested cross-validation to predict assessor scores for all videos. Agreement between unseen participant (i.e. test group participants that were not used to train the model) predictions and each individual assessor's scores were compared using quadratic weighted kappa. One sample t-tests (to determine over/underprediction against clinician ratings) and one-way ANOVA (to determine differences between networks) were applied to the four networks. RESULTS: The machine learning predictions have similar agreement to experienced human assessors, with no statistically significant (p < 0.05) difference for any match contingency. There was no statistically significant difference between the predictions from the four networks (F = 0.119; p = 0.949). The four networks did however under-predict scores with small effect sizes (p range = 0.007 to 0.040; Cohen's d range = 0.156 to 0.217). CONCLUSIONS: This study demonstrated that machine learning can perform similarly to experienced clinicians when subjectively assessing arm movement abnormality in people with ABI. The relatively small sample size may have resulted in under-prediction of some scores, albeit with small effect sizes. Studies with larger sample sizes that objectively and automatically assess dynamic movement in both local and telerehabilitation assessments, for example using smartphones and edge-based machine learning, to reduce measurement error and healthcare access inequality are needed.

Neuromuscular Control and Resistance Training for People With Chronic Low Back Pain: A Randomized Controlled Trial.

OBJECTIVE: To determine if adding lumbar neuromuscular control retraining exercises to a 12-week program of strengthening exercises had greater effect for improving disability than 12 weeks of strengthening exercises alone in people with chronic low back pain (LBP). DESIGN: Single-center, participant- and assessor-blinded, comparative effectiveness randomized controlled trial. METHODS: Sixty-nine participants (31 females; 29 males; mean age: 46.5 years) with nonspecific chronic LBP were recruited for a 12-week program involving lumbar extension neuromuscular retraining in addition to resistance exercises (intervention) or 12 weeks of resistance exercises alone (control). The primary outcome measure was the Oswestry Disability Index. Secondary outcome measures included the Numeric Rating Scale, Tampa Scale for Kinesiophobia, Pain Self-Efficacy Questionnaire, and the International Physical Activity Questionnaire. Outcomes were measured at baseline, 6 weeks, and 12 weeks. RESULTS: Forty-three participants (22 control, 21 intervention) completed all outcome measures at 6 and 12 weeks. Fourteen participants were lost to follow-up, and 12 participants discontinued due to COVID-19 restrictions. Both groups demonstrated clinically important changes in disability, pain intensity, and kinesiophobia. The difference between groups with respect to disability was imprecise and not clinically meaningful (mean difference, -4.4; 95% CI: -10.2, 1.4) at 12 weeks. Differences in secondary outcomes at 6 or 12 weeks were also small with wide confidence intervals. CONCLUSIONS: Adding lumbar neuromuscular control retraining to a series of resistance exercises offered no additional benefit over resistance exercises alone over a 12-week period. J Orthop Sports Phys Ther 2024;54(5):1-10. Epub 18 March 2024. doi:10.2519/jospt.2024.12349.

Associations between physical activity and development in preschool-aged children born <30 weeks' gestation: a cohort study.

OBJECTIVE: To investigate the effect of physical activity (PA) on development (motor, cognitive, social-emotional) in children 4-5 years old born <30 weeks' gestation, and to describe subgroups of children at risk of low PA in this cohort. DESIGN: Longitudinal cohort study. PATIENTS: 123 children born <30 weeks were recruited at birth and assessed between 4 and 5 years' corrected age. MAIN OUTCOME MEASURES: Development was assessed using the Movement Assessment Battery for Children, Second Edition (MABC-2), Little Developmental Coordination Disorder Questionnaire (L-DCDQ), Wechsler Preschool and Primary Scale of Intelligence (Fourth Edition; WPPSI-IV), and Strengths and Difficulties Questionnaire (SDQ). To measure PA, children wore an accelerometer and parents completed a diary for 7 days. Effects of PA on developmental outcomes, and associations between perinatal risk factors and PA, were estimated using linear regression. RESULTS: More accelerometer-measured PA was associated with better MABC-2 aiming and catching scores (average standard score increase per hour increase in PA: 0.54, 95% CI 0.11, 0.96; p=0.013), and lower WPPSI-IV processing speed index scores (average composite score decrease per hour increase in PA: -2.36, 95% CI -4.19 to -0.53; p=0.012). Higher accelerometer-measured PA was associated with better SDQ prosocial scores. Major brain injury in the neonatal period was associated with less moderate-vigorous and less unstructured PA at 4-5 years. CONCLUSIONS: Higher levels of PA are associated with aspects of motor, cognitive and social-emotional skill development in children 4-5 years old born <30 weeks. Those with major brain injury in the neonatal period may be more vulnerable to low PA at preschool age.

Hamstring spasticity assessment: does the hip flexion angle impact outcomes?

PURPOSE: Hamstring spasticity is prevalent following neurological injury. The standardized assessment involves passive knee extension, in a position of 90° hip flexion. This creates passive insufficiency of the muscle and lacks ecological validity for walking, whereby the hip typically flexes to a maximum of 40° during swing phase, while the knee extends. This study compared assessment outcomes when completed in 40° and 90° hip flexion. METHODS: The Modified Ashworth Scale and Modified Tardieu Scale, were performed on 35 adults with a neurological condition. Each participant was assessed by three assessors, resulting in 105 trials at 40° and 90°. RESULTS: There was a significant increase in the proportion of trials rated as spastic using the Modified Ashworth Scale (p=.012, phi=.27), and Modified Tardieu Scale (p<.001, phi=.36), and the severity of spasticity using the Modified Ashworth Scale (p<.001, effect size (ES)=.50), and Modified Tardieu Scale (p<.001 ES=.47), at 90° hip flexion. The angle of reaction occurred 32° earlier at 90° hip flexion (p<.001, ES = 1.61). CONCLUSIONS: Completing hamstring assessments in 40° hip flexion may reduce the passive insufficiency and improve the ecological validity of assessment, for walking. This may assist in the selection of patients requiring intervention, when their goal relates to walking.

The position of the hip joint impacts hamstring spasticity assessment outcomes, regardless of the clinical outcome measure chosenThe application of bedside assessment methods in a manner reflective of functional tasks may assist in selecting individuals who require active spasticity interventionAs per international guidelines, the use of validated outcome measures in a goal directed and patient centered manner is required to maximize patient care.

Controlling modified Tardieu scale assessment speeds to match joint angular velocities during walking impacts spasticity assessment outcomes.

OBJECTIVE: To investigate whether tailoring the speed of the Modified Tardieu Scale to reflect an individual's joint angular velocity during walking influences spasticity assessment outcomes. DESIGN: Observational trial. SETTING: Inpatient and outpatient neurological hospital department. SUBJECTS: Ninety adults with lower-limb spasticity. INTERVENTIONS: N/A. MAIN MEASURES: The Modified Tardieu Scale was used to assess the gastrocnemius, soleus, hamstrings and quadriceps. The V1 (slow) and V3 (fast) movements were completed as per standardised testing. Two additional assessments were completed, reflecting joint angular velocities during walking based on (i) a healthy control database (controlled velocity) and (ii) the individual's real-time joint angular velocities during walking (matched velocity). The agreement was compared using Cohen's and Weighted Kappa statistics, sensitivity and specificity. RESULTS: There was poor agreement when rating trials as spastic or not spastic at the ankle joint (Cohen's Kappa = 0.01-0.17). Trials were classified as spastic during V3 and not spastic during the controlled conditions in 81.6-85.1% of trials when compared to stance phase dorsiflexion angular velocities and 48.0-56.4% when compared to swing phase dorsiflexion angular velocities. The severity of muscle reaction demonstrated poor agreement at the ankle (Weighted Kappa = 0.01-0.28). At the knee, there was a moderate-excellent agreement between the V3 and controlled conditions when rating a trial as spastic or not spastic (Cohen's Kappa = 0.66-0.84) and excellent agreement when comparing severity (Weighted Kappa = 0.73-0.94). CONCLUSION: The speed of assessment impacted spasticity outcomes. It is possible that the standardised protocol may overestimate the impact spasticity has on walking, especially at the ankle.

Discordance Between Self-Reported and Performance-Based Physical Function in Patients Who Have Knee Osteoarthritis: Associations With Pain Intensity and Negative Affect.

BACKGROUND: Although self-reported measures of physical disability are strong indication criterion for total knee arthroplasty (TKA) in painful knee osteoarthritis (OA), some patients may report greater-than-observed disability. Contributing factors to this discordance are relatively unexplored. We aimed to examine whether pain and negative affect, including anxiety and depression, were associated with the discordance of self-reported measures with performance-based measures (PPM) of physical function. METHODS: We used cross-sectional data (n = 212) from two randomized rehabilitation trials in knee OA. All patients were assessed for knee pain intensity and symptoms of anxiety and depression. Self-reported function was assessed by the Western Ontario and McMaster Universities Arthritis Index (WOMAC) physical-function subscale. Objective performance-based measures (PPMs) of physical function were assessed by timed gait and stair tests. Continuous discordance scores were quantified by the difference in percentiles between WOMAC and PPMs (WOMAC-PPM), where a positive discordance, WOMAC-PPM >0, implied greater perceived than observed disability. RESULTS: Around 1 in 4 patients had >20 percentile units in WOMAC-PPM discordance. In Bayesian regression analyses, knee pain intensity had >99% posterior probability of positive associations with WOMAC-PPM discordance. Among patients awaiting TKA, anxiety intensity had approximately 99% probability of positive associations with discordance, and these associations had >65% probability of exceeding 10 percentile units. In contrast, depression had low (79% to 88%) probability of any association with discordance. CONCLUSION: In patients who have knee OA, a sizable proportion reported substantially greater physical disability than actually observed. Pain and anxiety intensity, but not depression, were meaningful predictors of this discordance. If validated, our findings may help in refining patient selection criteria for TKA.

Grpr expression defines a population of superficial dorsal horn vertical cells that have a role in both itch and pain.

ABSTRACT: Neurons in the superficial dorsal horn that express the gastrin-releasing peptide receptor (GRPR) are strongly implicated in spinal itch pathways. However, a recent study reported that many of these correspond to vertical cells, a population of interneurons that are believed to transmit nociceptive information. In this study, we have used a GRPR CreERT2 mouse line to identify and target cells that possess Grpr mRNA. We find that the GRPR cells are highly concentrated in lamina I and the outer part of lamina II, that they are all glutamatergic, and that they account for ∼15% of the excitatory neurons in the superficial dorsal horn. We had previously identified 6 neurochemically distinct excitatory interneuron populations in this region based on neuropeptide expression and the GRPR cells are largely separate from these, although they show some overlap with cells that express substance P. Anatomical analysis revealed that the GRPR neurons are indeed vertical cells, and that their axons target each other, as well as arborising in regions that contain projection neurons: lamina I, the lateral spinal nucleus, and the lateral part of lamina V. Surprisingly, given the proposed role of GRPR cells in itch, we found that most of the cells received monosynaptic input from Trpv1-expressing (nociceptive) afferents, that the majority responded to noxious and pruritic stimuli, and that chemogenetically activating them resulted in pain-related and itch-related behaviours. Together, these findings suggest that the GRPR cells are involved in spinal cord circuits that underlie both pain and itch.

Quiet standing postural control variables in subacute stroke: associations with gait and balance, falls prediction and responsiveness.

PURPOSE: To examine the construct validity, predictive validity and responsiveness of standing centre of pressure variables in subacute stroke. MATERIALS AND METHODS: Seventy-nine ambulatory individuals were assessed before inpatient rehabilitation discharge and three months later. Measures were: gait speed (6-metre walk), dynamic balance (step test), and quiet standing (Wii Balance Board). Centre of pressure speed, amplitude, standard deviation, root mean square, wavelet decomposition, and detrended fluctuation analysis were examined. Falls data were collected over a 12-month period post-discharge. RESULTS: Moderate strength correlations (r = -0.505 to -0.548) with gait speed and step test scores were shown for 3/26 centre of pressure variables (mediolateral speed, low and moderate frequency wavelet). Twenty-two participants fell and the prediction was significant for gait speed and step test (IQR-odds ratio (OR) = 4.00 & 3.21) and 3/26 centre of pressure variables (mediolateral low-frequency wavelet: IQR-OR = 2.71; mediolateral detrended fluctuation analysis: IQR-OR = 3.06; anteroposterior detrended fluctuation analysis: IQR-OR = 2.71). Significant changes over time occurred for gait speed and step test scores and 20/26 centre of pressure variables. CONCLUSIONS: Standing centre of pressure variables have limited validity to reflect dynamic balance and falls risk after stroke. Frequency and complexity measures warrant further exploration.Implications for rehabilitationOur findings indicate that quiet standing centre of pressure variables have limited validity to reflect dynamic balance tasks and predict falls after stroke.The mediolateral and higher frequency variables may be more strongly recommended than the commonly used total centre of pressure speed measure.Measures of signal frequency and complexity may provide insight into postural control mechanisms and how these change over time following stroke.

Potential contributing factors to upper limb associated reactions in people with acquired brain injury: an exploratory study.

PURPOSE: To determine which potential contributing factors are associated with upper limb associated reaction (AR) expression in individuals with acquired brain injury (ABI). METHODS: Forty-two participants underwent three-dimensional motion analysis at self-selected walking speed to generate the AR outcome measure, quantifying their upper limb kinematic deviation compared to healthy controls. Clinical assessment included: upper and lower limb hypertonicity, spasticity and strength, balance, dynamic walking stability, arm and leg function, anxiety, arm pain/discomfort, and fear of falling. RESULTS: Significant, moderate-to-strong correlations (r = 0.42-0.74, p < 0.05) existed between upper limb ARs and both hypertonicity and spasticity of the upper limb muscles and the knee extensors. Significant, moderate correlations to ARs (r = 0.42-0.59, p < 0.05) existed for balance, dynamic stability, upper limb strength, and arm function. The severity of AR was significantly different between those with and without hypertonicity of the four tested upper limb muscles, elbow and long finger flexor spasticity, knee extensor spasticity, and reduced dynamic stability (p < 0.05; effect sizes ≥0.80). However, these contributing factors were not present in all participants. CONCLUSIONS: Associated reactions are complex and multi-factorial. There were several significant correlations indicating that factors may influence AR severity. While positive upper motor neuron syndrome features should be prioritised for clinical assessment, these factors are not prerequisites for ARs.IMPLICATIONS FOR REHABILITATIONUpper limb associated reactions are a complex and multi-factorial phenomenon.Upper limb muscle hypertonicity and spasticity should be prioritised for assessment; however, they are not prerequisites for associated reactions.Hypertonicity and spasticity should be differentiated as they may have differing relationships to associated reactions.Knee extensor hypertonicity and spasticity, postural stability, upper limb strength, and arm function may also be contributing factors to consider.

Strength training to improve walking after stroke: how physiotherapist, patient and workplace factors influence exercise prescription.

Background:Muscle weakness is well established as the primary impairment that affects walking after stroke and strength training is an effective intervention to improve this muscle weakness. Observation of clinical practice however has highlighted an evidence-practice gap in the implementation of evidence-based strength training guidelines. Objective: To explore perceived barriers and facilitators that influence Australian physiotherapy practices when prescribing strength training with stroke survivors undergoing gait rehabilitation. Methods: Semi-structured interviews were conducted with a convenience sample of physiotherapists currently providing rehabilitation services to patients following stroke in Australia. Interviews were transcribed verbatim and line-by-line thematic analysis was undertaken to create themes and sub-themes. Results: Participants were 16 physiotherapists (12 females) with 3 months - 42 years experience working with people after stroke. Major themes identified were1) patient factors influence the approach to strength training; 2) interpretation and implementation of strength training principles is diverse; and 3) workplace context affects the treatment delivered. Physiotherapists displayed wide variation in their knowledge, interpretation and implementation of strength training principles and strength training exercise prescription was seldom evidence or guideline based. Workplace factors included the clinical preference of colleagues, and the need to modify practice to align with workforce resources. Conclusions: Implementation of strength training to improve walking after stroke was diverse. Therapist-related barriers to the implementation of effective strength training programs highlight the need for improved knowledge, training and research engagement. Limited resourcing demonstrates the need for organizational prioritization of stroke education and skill development. Narrowing the evidence-practice gap remains a challenge.

The Effectiveness of Aquatic Plyometric Training in Improving Strength, Jumping, and Sprinting: A Systematic Review.

CONTEXT: Aquatic plyometric training may provide benefits due to reduced joint loading compared with land plyometric training; however, the reduced loading may also limit performance gains. OBJECTIVE: To systematically review the effect of aquatic plyometric training on strength, performance outcomes, soreness, and adverse events in healthy individuals. EVIDENCE ACQUISITION: Five databases were searched from inception to June 2020. Quality assessment and data extraction were independently completed by 2 investigators. When similar outcome measures were used, standardized mean differences were calculated. EVIDENCE SYNTHESIS: A total of 19 randomized controlled trials with 633 participants (mean age, range 14-30 y) were included. Aquatic plyometric training was most commonly performed in waist to chest deep water (12/19 studies), 2 to 3 times per week for 6 to 12 weeks (18/19 studies), with final program foot contacts ranging from 120 to 550. Meta-analyses were not completed due to the clinical and statistical heterogeneity between studies. Compared with land plyometric training, aquatic plyometric training exercises and dosage were replicated (15/16 studies) and showed typically similar performance gains (3/4 knee extensor strength measures, 2/4 leg extensor strength measures, 3/4 knee flexor strength measures, 7/10 vertical jump measures, 3/3 sprint measures). In total, 2 of 3 studies monitoring muscle soreness reported significantly less soreness following training in water compared with on land. Compared with no active training (no exercise control group or passive stretching), most effect sizes demonstrated a mean improvement favoring aquatic plyometric training (23/32 measures). However, these were not significant for the majority of studies measuring isokinetic knee strength, vertical jump, and sprinting. The effect sizes for both studies assessing leg press strength indicated that aquatic plyometric training is significantly more effective than no training. CONCLUSION: Aquatic plyometric training appears similarly effective to land plyometric exercise for improving strength, jumping, and sprinting and may be indicated when joint impact loading needs to be minimized. However, the low quality of studies limits the strength of the conclusions.

Lower limb muscle performance during a closed chain single leg squat and a squat jump in people with leg weakness after stroke: A comparative study.

OBJECTIVE: To determine if the intention to perform an exercise at speed leads to beneficial alterations in kinematic and kinetic components of the movement in people with post-stroke hemiplegia. DESIGN: Comparative study. SETTING: Subacute metropolitan rehabilitation hospital. PARTICIPANTS: Convenience sample of patients admitted as an inpatient or outpatient with a diagnosis of stroke with lower limb weakness, functional ambulation category score ≥3, and ability to walk ≥14metres. METHODS: Participants performed a single leg squat exercise on their paretic and nonparetic legs on a leg sled under three conditions: 1) self-selected speed (SS), 2) fast speed (FS), 3) jump squat (JS). Measures of displacement, flight time, peak concentric velocity, and muscle excitation (via electromyography) were compared between legs and conditions. RESULTS: Eleven participants (age: 56 ± 17 years; median time since stroke onset: 3.3 [IQR 3,41] months) were tested. All participants achieved a jump during the JS, as measured by displacement and flight time respectively, on both their paretic (0.25 ± 0.16 m and 0.42 ± 0.18 s) and nonparetic (0.49 ± 0.36 m and 0.73 ± 0.28 s) legs; however it was significantly lower on the non-paretic leg (p p Conclusions: Speed affects the kinematic and kinetic components of the movement. Performing exercises ballistically may improve training outcomes for people post-stroke.

Assessment of upper limb abnormalities using the Kinect: Reliability, validity and detection accuracy in people living with acquired brain injury.

Upper limb kinematic abnormalities are prevalent in people with acquired brain injury (ABI). We examined if the Microsoft Kinect for Xbox One (Kinect) reliably (test-retest) and validly (concurrent) quantifies upper limb kinematics, and accurately classifies abnormalities (sensitivity/specificity), in an ABI cohort when compared to three-dimensional motion analysis (3DMA) and a subjective rating scale. We compared 42 adults with ABI to 36 healthy control (HC) participants. Walking trials were recorded by 3DMA and Kinect at self-selected (SSWS) and fast (FWS) walking speeds. When classifying abnormalities for 3DMA and Kinect, a 95% reference range (based on HC data) was calculated using the Kinematic Deviation Score worst axis (KDSw); values outside of this range were classified abnormal. Scores ≥ 2 in the subjective rating scale, based on International Classification of Functioning, Disability and Health Framework's Qualifiers Scale, were considered abnormal. Test-retest reliability and concurrent validity were determined using intra-class correlation coefficient (Absolute ICC2,1) and Pearson's or Spearman's correlation respectively. Fisher's Exact Test was conducted to determine sensitivity and specificity between each combination of the two methods. Strong test-retest reliability was observed for 3DMA (median(IQR) ICC:0.86(0.85-0.90)). Kinect showed overall strong SSWS test-retest reliability (ICC:0.87(0.84-0.91)) and moderate FWS test-retest reliability (ICC:0.61(0.56-0.65)). Concurrent validity between 3DMA and Kinect was overall moderate. Sensitivity and specificity between 3DMA, Kinect and subjective scores were overall modest. Our results suggest caution should be used if implementing Kinect as its validity is modest against criterion-reference 3DMA; however, given its reliability and similar sensitivity/specificity to 3DMA further responsiveness research is warranted.

What Factors Influence Clinicians' Use of Technology in Neurorehabilitation? A Multisite Qualitative Study.

OBJECTIVE: Technology is being increasingly used for physical assessment and interventions in health care settings. However, clinical adoption is relatively slow, and the factors affecting use remain underexplored. This study aimed to investigate factors influencing technology use by clinicians working in neurorehabilitation. METHODS: In this qualitative study, 9 physical therapists and 9 occupational therapists (N = 18) were recruited from urban and regional locations in Australia and in Singapore. Three 60-minute focus groups were conducted via video conferencing. Each group comprised 3 physical therapists and 3 occupational therapists working across different neurorehabilitation settings. Participants were asked to discuss which technologies they used in their workplace for physical assessment and treatment and barriers, motivators, and future desires for technology use. Transcripts were analyzed independently using an inductive approach to generate codes and themes. RESULTS: Our results comprised 3 themes and 7 categories. These were encompassed by a single overarching theme, namely "Technology use is influenced by the benefits and challenges of the technology itself, users, and organizational context." Themes showed that technology should promote effective interventions, is preferred if easy to use, and should be dependable. Furthermore, clinical reasoning is important, and users have varying levels of receptivity and confidence in technology use. Also, organizational resources are required, along with supportive cultures and processes, to facilitate technology use. CONCLUSIONS: The themes identified multiple and interlinking factors influencing clinicians' use of technology in neurorehabilitation settings. Clinicians often consider context-specific benefits and challenges when deciding whether to use technology. Although our study found that clinicians generally perceived technology as having a beneficial role in improving health outcomes, there were several challenges raised. Therefore, the characteristics of the technology itself, individual users, and organizational context should be considered. IMPACT: These findings will guide successful technology implementation and future developments.

Paretic and Nonparetic Step Tests Are Noninterchangeable in Stroke: A Prospective Cohort Study.

OBJECTIVE: The step test (ST) is a common clinical assessment of dynamic balance among survivors of stroke. The ST assesses a person's ability to place their paretic (paretic ST) or nonparetic (nonparetic ST) foot rapidly and repeatedly on and off a standardized block while standing. No study has formally explored if the 2 tests are interchangeable. Our study aimed to: (1) differentiate the correlates of paretic and nonparetic ST, and (2) compare their associations with physical function and falls. METHODS: Eighty-one survivors of stroke were consecutively recruited from inpatient rehabilitation units (n = 4) and were assessed within 1 week prior to discharge. In addition to the ST, a handheld dynamometer and computerized posturography were used to measure lower limb muscle strength and standing balance, respectively. Self-selected gait speed and Timed Up and Go test were also assessed as measures of physical function. Falls data were monitored for 12 months post discharge using monthly calendars. Multivariable regression analyses were used to differentiate (1) the correlates of paretic and nonparetic STs, and (2) their associations with physical function and falls. RESULTS: The median score for the paretic and nonparetic STs were 8 and 9 steps, respectively. Paretic ankle plantar-flexor and dorsiflexor strength were the strongest correlates of nonparetic ST, whereas both paretic ankle and knee extensor strength were the strongest correlates of paretic ST. In multivariable analyses adjusting for each other, both STs were independently associated with gait speed and Timed Up and Go scores. Paretic ST (odds ratio = 0.37; 95% CI = 0.22 to 0.62) was a stronger predictor than nonparetic ST (odds ratio = 0.51; 95% CI = 0.34 to 0.78) in predicting future falls. CONCLUSION: This study confirmed that the paretic and nonparetic STs are noninterchangeable. ST scores should be assessed separately to achieve a more complete interpretation. IMPACT: To our knowledge, this study is the first to objectively evaluate the similarities and differences between paretic and nonparetic STs. This information may refine the use and interpretation of the 2 STs for survivors of stroke.

Upper Limb Associated Reactions: The Relationship Between Movement Kinematics and Muscle Activity in Seated Versus Walking Testing.

OBJECTIVE: The aims of this study were to (1) evaluate the relationships between stationary and dynamic associated reaction (AR) tests in people with acquired brain injury using surface electromyography (sEMG) muscle activity and three-dimensional motion analysis kinematic measures and (2) assess the test-retest reliability of sEMG and seated tests of ARs. DESIGN: Forty-two adults with acquired brain injury underwent AR testing with seated contralateral maximal voluntary isometric contraction tests and walking (self-selected and fast speeds). Associated reaction measurements included biceps brachii sEMG, elbow goniometry, and three-dimensional motion analysis kinematics during walking. Pearson correlations evaluated the relationships between seated and dynamic walking AR tests and between muscle activity and kinematic measures. Chronic participants were reassessed 1 wk later for reliability. RESULTS: A strong (r = 0.65) and moderate (r = 0.53) relationship existed for biceps brachii sEMG during seated and walking tests at self-selected and fast walk, respectively. A weak to moderate relationship existed between biceps brachii sEMG and kinematics during walking and between seated and walking measures of ARs (r = 0.23-0.53). All tests had strong to very strong test-retest reliability (intraclass correlation coefficients, >0.78). CONCLUSION: Seated contralateral maximal voluntary isometric contraction tests correlate only weakly to moderately with AR walking kinematics and moderately to strongly with biceps brachii activation during walking. Moderate relationships exist between sEMG and kinematics, indicating that they may provide different information for ARs.

Strength, Motor Skills, and Physical Activity in Preschool-Aged Children Born Either at Less Than 30 Weeks of Gestation or at Term.

OBJECTIVE: Children born <30 weeks of gestation have more motor impairment than do children born at term (37-42 weeks gestation), but reported outcomes have largely focused on cerebral palsy and developmental coordination disorder. The aim of this study was to compare muscle strength, motor skills, and physical activity (PA) of preschool-aged children born <30 weeks with those born at term. METHODS: In this cohort study, 123 children born <30 weeks and 128 born at term were assessed. Children were aged ≥4 years, 0 months and <6 years, 0 months' corrected age at the time of the assessment. Outcomes included grip strength (kg), Movement Assessment Battery for Children 2nd edition (MABC-2), Little Developmental Coordination Disorder Questionnaire, accelerometer-measured PA, and a parent-completed PA diary. Linear regression and mixed effects models were used to examine differences between children born <30 weeks and those born at term. RESULTS: Children born <30 weeks had poorer grip strength (preferred hand; mean difference [95% CI] -0.60 kg [-1.04 to -0.15]) and poorer motor competence (Movement Assessment Battery for Children 2nd edition standard score mean difference -2.17 [-3.07 to -1.27]; Little Developmental Coordination Disorder Questionnaire total score mean difference -5.5 [-9.2 to -2.8]) than term-born children. Children born <30 weeks also completed fewer minutes of accelerometer-measured PA (mean difference -41 minutes [-62 to -20]), more minutes of accelerometer-measured stationary behavior (mean difference 33 minutes [12 to 54]), and more minutes of parent-reported screen time (mean difference 21 minutes [10 to 32]) per day. CONCLUSION: Preschool-aged children born <30 weeks had poorer muscle strength, motor skills, and PA levels than term-born children. These findings suggest that preschool-aged children born <30 weeks may benefit from enhanced surveillance and PA promotion to improve life-long health outcomes. IMPACT: In our study, children born <30 weeks had reduced muscle strength and poorer motor skills, participated in less PA, and had more stationary and screen behavior than term-born children. These findings emphasize that awareness of multidomain motor deficits in children born <30 weeks' gestation is needed in clinical practice. Given the associations between higher PA and health benefits and the recognition that PA levels can track from early childhood into adulthood, our study highlights the need for assessment and promotion of PA in preschool-aged children born <30 weeks' gestation. Lay Summary. Preschool-aged children born <30 weeks' gestation have poorer strength, motor skills, and physical activity behaviors than their term-born peers. Clinicians and early childhood educators should recognize that the preschool period is a critical time for the assessment and promotion of PA in children born <30 weeks.

Clinical spasticity assessment using the Modified Tardieu Scale does not reflect joint angular velocity or range of motion during walking: Assessment tool implications.

OBJECTIVE: Spasticity assessment is often used to guide treatment decision-making. Assessment tool limitations may influence the conflicting evidence surrounding the relationship between spasticity and walking. This study investigated whether testing speeds and joint angles during a Modified Tardieu assessment matched lower-limb angular velocity and range of motion during walking. DESIGN: Observational study. SUBJECTS: Thirty-five adults with a neurological condition and 34 assessors. METHODS: The Modified Tardieu Scale was completed. Joint angles and peak testing speed during V3 (fast) trials were compared with these variables during walking in healthy people, at 0.400.59, 0.600.79 and 1.401.60 m/s. The proportion of trials in which the testing speed, start angle, and angle of muscle reaction matched the relevant joint angles and angular velocity during walking were analysed. RESULTS: The Modified Tardieu Scale was completed faster than the angular velocities seen during walking in 88.7% (0.400.59 m/s), 78.9% (0.600.79 m/s) and 56.2% (1.401.60 m/s) of trials. When compared with the normative dataset, 4.2%, 9.5% and 13.7% of the trials met all criteria for each respective walking speed. CONCLUSION: When applied according to the standardized procedure and compared with joint angular velocity during walking, clinicians performed the Modified Tardieu Scale too quickly.

Digital bathroom scales with open source software provide valid dynamic ground reaction force data for assessment and biofeedback.

BACKGROUND: Measuring dynamic vertical ground reaction force allows for assessment of important clinical and physical capacity factors such as weight bearing asymmetry, force distribution, and rate of force development. However, current technologies for accurately assessing ground reaction force are typically expensive. RESEARCH QUESTION: The aim of this study was to examine the validity and reliability of obtaining static and dynamic ground reaction force data from low-cost modified digital bathroom scales. METHODS: Four modified bathroom scales, two units each of two different brands, were examined. Repeated mechanical loading trials were performed with known loads ranging from 0.01 to 65 kg, with acquired data compared against the known loading to calculate accuracy, hysteresis, and non-linearity. Dynamic trials consisting of 5 times sit-to-stand and weight-shifting were performed by 32 adults. Absolute and relative agreement intraclass correlation coefficient, and Pearson's and Spearman's correlations were performed to determine validity and reliability for the mechanical tests. Bland-Altmann plots were created for each comparison. Mean absolute error (MAE) and unbiased cross-correlation were performed on the dynamic data, comparing the calibrated data to the known values from a Bertec force platform. RESULTS: Hysteresis and non-linearity were excellent (<0.2 % full-scale), and mechanical test results showed excellent reliability and validity. Cross-correlation results for the dynamic data were excellent, however MAE for the more rapid sit-to-stand task was higher than the slower weight-shifting test. This may have been due to the low default sampling rate for the lowest noise setting of the HX711 amplifier (10 Hz). SIGNIFICANCE: In summary, our results suggest that digital bathroom scales can be easily and inexpensively modified to obtain accurate vertical ground reaction force data, with sensitivity to detect changes of as little as 0.01 kg.