Evidence For Clinical and Research Walking Activity Measurement in Cerebral Palsy with the StepWatch (SW) Kristie F. Bjornson, PT, PhD, MS Associate Professor Pediatrics Seattle Children s Research Institute University of Washington Kristie.bjornson@seattlechildrens.org AACPDM 218 FINANCIAL DISCLOSURE AACPDM 72 nd Annual Meeting October 9-13, 218 Speaker Name: Kristie Bjornson, PT, PhD, MS 1. Disclosure of Relevant Financial Relationships Grant/Research support from: F31NS4874-NINDS SCH Dept of Orthopedic Surgery SCRI Academic Enrichment Fund K23HD6764 -NICHD R21 HD77186- NICHD/NCMRR 2. Disclosure of Off-Label and/or investigative uses: I will not discuss off label use and/or investigational use in my presentation. Objectives: Understand validity & accuracy of the SW strides taken in typically developing children/youth (TDCY) &with CP. Understand the walking activity levels and intensity of TDCY &with CP. Examine evidence for SW monitoring duration by Gross Motor Function Level (GMFCS) in children/youth with CP. Exemplars- clinical & research SW application in children with CP. 1
Physical Activity Walking Activity When we are not looking3 how and how much are they walking? Terminology: Walking Activity (WA) step or stride taken for mobility, depending on device may be step or stride Step-counts both left and right steps Stride step of one leg/side-3dg lab 2
ICF model: WHO 21 Health Condition Body Functions & Structures Activities Participation Environmental Factors Personal Factors International Classification of Functioning, Disability & Health. 21; WHO Walking Activity Measurement Level of Ability versus Level of Activity Capacity Performance Relationship of Stride Activity to Mobilitybased Life Habits in Children with Cerebral Palsy (Bjornson, 213) Average total strides/day was positively associated with the Personal Care, Housing, Mobility, and Recreation Life-H categories. Moderate/High walking stride rates (Ave > 3 stride/min/day) was associated with all categories Walking activity performance is significantly associated with levels of participation in mobility-based life habitsfor ambulatory children with CP. 3
Why the StepWatch? Left hip ActiGraph: child with Spastic Diplegia Right hip Stott, MacKey, 211 4
Pediatric StepWatch Accuracy/Precision & comparison to Pedometers: Mitre et al (29)-treadmill trial Lean and obese children Omron and Digiwalkerpedometers undercounting compared to manual counts (worse at slower speeds) StepWatch had negligible error to manual counts of steps taken StepWatchAccuracy to Observed Strides: TDY 2 normally developing children Age groups 5-7 years & 9-11 years 3-Two week intervals: 2 months apart Comparison manual counts Walking 96-97% Running 99% Song K. J Peds Ortho, 26: 245-249;26 5
StepWatch Two dimensional accelerometer Detects foot leaving the surface Completely sealed Worn with strap or ankle cuff Continuously records steps/time interval Up to two months duration AKA SAM, StepWatch3 and GAM www.modushealth.com NEW UPDATE 218 StepWatch 4 (SW4) - Activity Monito $4 eawith ipad app App $13 1x Additional $ monthly cloud-based rechargeable SW4 available 218 support@modushealth.com Seattle Clinical/Research SW Monitoring Guidelines Individually Set: Sensitivity Cadence Pre/Post intervention Wearing 7 to 14 days Analyze 5 to 14 days Depends on clinical question 6
StepWatch: How many days monitored TDY (n= 428, ages 2-13 yrs) (Kang 214) Need to monitor ave 4.14 days (range 3 to 6 by days 2 year age bands) Children with CP: (n=29) (Ishikawa, 213) GMFCS: Level I 6 days Level II 5 days Level III 4 days Kang et al Phys Meas. 214 Ishikawa et al APRM. 213 What do we know about walking with SW in TDY? Measurement of Walking Activity throughout Childhood: Influence of Leg Length Bjornson et al, Ped Ex Sci 21 7
Sample: 428 TDY children ages 2 to 15 years 3 boys / 3 girls per age group 7 groups of 2 year increments Calibration Accuracy: ave 1% (range 9-112, sd 4.) Age Group Average 6-min (yrs) Gender (n) Stride/Day peak 2-min peak 1-min peak 2-3 Boys (3) 8,159 (2,677) 28 (8) 4 (8) 7 (7) Girls (3) 7,837 (1,771) 28 (5) 39 (7) 73 (1) Total (6) 7,998 (2,257) 28 (7) 39 (8) 72 (7) 4-5 Boys (31) 9,411 (3,214) 3 (8) 44 (1) 71 (6) Girls (31) 8,726 (1,992) 29 (6) 41 (8) 71 (7) Total (62) 9,69 (2,674) 29 (7) 42 (9) 71 (7) 6-7 Boys (32) 9,88 (3,67) 31 (7) 43 (7) 68 (7) Girls (3) 9,83 (2,492) 29 (5) 42 (6) 7 (6) Total (62) 9,794 (2,81) 3 (6) 43 (6) 69 (7) 129 Average stride/day 2 15 1 73 19 15 151 222 27 287 384 391 5 2-3 yr 4-5 yr 6-7 yr 8-9 yr 1-11 yr 12-13 yr 14-15 yr Age 8
Adjusted for leg length average stride/day 2 15 1 5 73 82 129 15 151 222 277 27 384 2-3 yr 4-5 yr 6-7 yr 8-9 yr 1-11 yr Age group 12-13 yr 14-15 yr Basis for Pediatric Walking Intensity Cut-points for StepWatch (SW) Intense walking adult US population documented peak step/min rate of 11 (Tudor-Locke, 212) Intense walking bursts for children (< 18 years of age) are documented at 18 to 146 peak steps/min rates (1-12). (Barreira, 212, Bjornson 21, Tudorlocke, 22) moderate to vigorous physical activity (MVPA) = 12 step/min -1 to 14 y/o boys and girls with another pedometer (Graser, 211) High intensity walking for StepWatch > 6 stride/min-as it counts only one leg. 1 7 13 178 Maximal 1 minute strides 8 6 4 29 213 268 275 272 353 371 41 2 2-3 yr 4-5 yr 6-7 yr 8-9 yr 1-11 yr Age group 12-13 yr 14-15 yr 9
Walking activity with StepWatch in children with CP? Neuromuscular Scoliosis (VEPTR) TDY 1
Ambulatory Physical Activity Performance in Youth with Cerebral Palsy & Youth Developing Typically Bjornson Physical Therapy 87(3), 27 Average step/day % All Time Active Ratio Medium to low Activity % Time High Activity CP (n=81) TDY (n=3) 4,222 6,739. 4.2 49.6..33.47. 5.6 9.7. p 12 42 Average Daily Total Step count/stepwatch 1 8 6 4 2 GMFCS level III GMFCS level II GMFCS level I Activity Capacity Functional Categories TDY to levels I, II & III p <.1, TDY to level I p=.o4,level I to II p=.9, Level I to III p<.1, level III to II p <.1. TDY Compared walking with StepWatch 5 days of monitoring 29 youth with CP 368 TDY Ages 2-13 years Intensity: Low 1-3 stride/min Moderate 31-6 stride/min High > 6 stride/min 11
45 4 35 3 25 2 15 1 5 3992 3856 TDY GMFCS level I GMFCS level II GMFCS III 533 Low (1-3) Mod (31-6) High > 6 45 4 35 3 25 2 15 1 5 3992 3856 TDY 3436 GMFCS level I 2599 GMFCS level II GMFCS III 533 262 Low (1-3) Mod (31-6) High > 6 45 4 35 3 25 2 15 1 5 3992 3856 TDY 3436 2977 GMFCS level I 2599 GMFCS level II 24 GMFCS III 533 262 213 Low (1-3) Mod (31-6) High > 6 12
45 4 35 3 25 2 15 1 5 3992 3856 TDY 3436 2977 GMFCS level I 2599 GMFCS level II 24 GMFCS III 1347 433 533 262 213 36 Low (1-3) Mod (31-6) High > 6 Clinical/Research Exemplars: StepWatch Measurement: Longitudinal monitoring- Scoliosis Diplegia (multiple interventions) Treadmill training Orthotics SW combined with GPScommunity mobility Neuromuscular Scoliosis (VEPTR): Average Steps/Day 6 5 4 3 2 1 Pre APR 3 Post Dec 3 Post Apr 5 Post Feb 7 13
Average steps/day: CP Spastic diplegia 8 y/o -GMFCS II 7 6 5 4 3 2 1 Nov-99 Btx 3/ Bac Btx streng 8/ 3/1 Without AFO's Pre Sx 8/1 post sx 4/2 F/U 1/4 Walking intensity: CP-GMFCS II 1 9 8 7 6 5 4 3 2 1 Low Med High Baseline 11/99 Botox 3/ BAC BTX Streng 8/ Without AFO's 3/1 Pre cardiac/ortho Sx Postsx 4/2 F/U 1/4 Short-burst interval treadmill training walking capacity & performance in cerebral palsy: a pilot study Bjornson, et al Dev Neurorehab 218 Funding: R21 HD77186- NICHD/NCMRR 14
Average Strides/day at baseline, post SBLTT and 6 weeks post SBLTT (n=12). Walking Performance (n= 12, PRE/POST SBLTT) Average Total Steps/day BL Mean (SD) 2677 (16) Post 1 Mean chang e p value Post 2 Mean Chang e p value +1712 <.1 +948 <. 1 Percent Time 37.1 (9.5) +7.68.6 +4.89.55 walking Percent Time > 3 8.37 (4.) +4.4.4 +3.8.4 steps/min(mod/hig h) # Step >3 8245 (442) +991 <.1 +627 <. steps/min 1 Peak Activity Index 33.9 (5.4) +9.4 <.1 +6.1 <. (avetop 3 one 1 min) Max # steps 6 mins 13.2 (4.2) +5.8.6 +4.2 <. 1 Max # steps 2 22.9 (4.3) +7.3 <.1 +7.1 <. Percent of total strides/day in low, moderate& high stride rates: 368 TDY, 29 youth with CP,12 youth with CP, Pre/ Post short-burst LTT. 15
Orthotic Intervention: Walking Activity with StepWatch SW Orthotics: n= 8 diplegia 4 y/o, spastic diplegia CP: Average # of Strides/day- low, mod & high 45 4 429 3862 Average Strides/day 35 3 25 2 15 1 5 TDY (n=62, 4-5 y/o) 742 Low (1-3) Mod (31-6) High > 6 16
4 y/o, spastic diplegia CP: Average # of Strides/day- low, mod & high Average Strides/day 45 4 35 3 25 2 15 1 5 429 287 3862 2175 TDY (n=62, 4-5 y/o) 4 y/o, AFO- OFF 742 114 Low (1-3) Mod (31-6) High > 6 4 y/o, spastic diplegia CP: Average # of Strides/day- low, mod & high Average Strides/day 45 4 35 3 25 2 15 1 5 429 287 3755 3862 2175 3359 TDY (n=62, 4-5 y/o) 4 y/o, AFO- OFF 4 y/o, AFO- ON 742 114492 Low (1-3) Mod (31-6) High > 6 What are they really doing? Community Walking Activity in Cerebral Palsy: StepWatch & Global Positioning System (GPS) Bjornson KF, Hurvitz P, Kerfeld C. (215) Funding: SCRI CHBD Stimulus Fund 213 NIH R21 HD77186 17
Stride count intensity home/community (low, med, high), pre/post Interval Treadmill training (n=1) Percent walking time-home/community, pre/post Interval Treadmill Training (n=12). 18
StepWatch -Take Home Highest accuracy to strides taken of current devices Published normative data for TDCY Emerging data for children with CP Evidence- Monitoring duration GMFCS level I = 6 days; II = 5 days; III = 4 days Pediatric cut points for intensity analysis Potential SW Clinical/Research Applications PRE/POST New assistive device/orthotics Botox L/E/serial casting Ortho surgery- SEML and Spinal SDR Oral medication movement disorders Dose change of ITB pump Burst of therapy (OT/PT) QUESTIONS? 19
References: Bjornson KF, Zhou C, Stevenson RD, Christakis D. Relation of stride activity and participation in mobility-based life habits among children with cerebral palsy.arch Phys Med Rehabil. 214 Feb;95(2):36-8. Bjornson KF, Zhou C, Stevenson R, Christakis D, Song K. Walking activity patterns in youth with cerebral palsy and youth developing typically. Disabil Rehabil. 214;36(15):1279-84. Bjornson KF, Belza B, Kartin D, Logsdon R, McLaughlin J, Thompson EA. The relationship of physical activity to health status and quality of life in cerebral palsy.pediatr Phys Ther. 28 Fall;2(3):247-53 Bjornson K, Song K, Lisle J, Robinson S, KillienE, Barrett T, et al. Measurement of walking activity throughout childhood: influence of leg length. Pediatric exercise science. 21;22(4):581-95. Bjornson, Lennon Walking and Physical Activity Monitoring in Children with Cerebral Palsy; Springer International Publishing AG 217B. Müller, S.I. Wolf (eds.), Handbook of Human Motion, Bjornson KF, Moreau N, Bodkin A. (218) Short-burst interval treadmill training walking capacity and performance in cerebral palsy: a pilot study. Dev Neurorehabil. 218 Apr 16:1-8 Ishikawa S, Kang M, Bjornson KF, Song K. Reliably Measuring Ambulatory Activity Levels of Children and Adolescents With Cerebral Palsy. Archives of Physical Medicine and Rehabilitation. 213;94(1):132-7. Kang M. Bjornson KF BT, Ragan BG, Song K. The minimum number of days required to establish reliable physical activity estimates in children aged 2 15 years. Physiological Measurement. 214;35(11):2229 TreacyD. et al. Validity of Different Activity Monitors to Count Steps in an Inpatient Rehabilitation SettingPhys Ther.217 May 1;97(5):581-588. Toth, LP et al.. Med Sci Sports Exerc 218StepWatch was the Most Accurate in Real World Walking 2