Task ICC ICC 95% CI ICC Interpretation7

Extension .965 (.077, .993) Poor to Excellent

Flexion .996 (.988, .999) Excellent

Left Side Flexion .957 (.860, 985) Excellent

Right Side Flexion .971 (.916, .990) Excellent

Table 1: Concurrent Validity between Smartphone Accelerometer and VICON

RESULTSConcurrent validity between body-worn accelerometer and 3D Motion Capture (Objective 1)• Overall we found that the accelerometer had similar accuracy to the VICON when measuring

thoracolumbar mobility.• Our most variable results came from thoracolumbar extension

-4

-2

0

2

4

6

8

0 10 20 30 40 50 60

Diff

eren

ce (B

ody-

Wor

n Ac

cele

rmot

er-

3D M

otio

n C

aptu

re)

Maximum Lateral Flexion Angle (3D Motion Capture) (Degrees)

+ 95 % LOA

- 95 % LOA

Mean

Task Net Angular Change Accelerometer – VICON (Degrees)

Bap 95% LOA (Degrees)

Extension 2.0 (0.0, 4.0)Flexion 0.3 (-3.8, 4.4)Right Side Flexion 0.0 (-4.6, 4.5)

A Mobile Assessment for Spinal Health: An Investigation of Concurrent Validity and Intra-rater Reliability

P. Quimio1, J. Bailey1, J. Blatt1, N. Conzelmann1, S. Cosgrove1, A. Mazaheri1, K. Zabjek11. Department of Physical Therapy, University of Toronto

INTRODUCTION

OBJECTIVES

METHODS

DISCUSSION

CONCLUSION

REFERENCES

• Age related musculoskeletal conditions has are associated with decline in locomotor function, increased risk of falls, and a decrease in quality of life123.

• Associated age related changes in local intervertebral segment mobility, descending central nervous system control and muscle strength have a negative influence on spinal mobility, and spinal health4.

• Early detection and consistent tracking of spinal mobility impairment are critical for a physical therapist’s clinical reasoning in determining an appropriate intervention.

Clinical assessment of spinal mobility: • active thoracolumbar mobility is assessed qualitatively through observation or quantitatively

through a forward bend test and a backward bend test5.

Mobile technology:• mobile phones (smartphone + accelerometer) have demonstrated promise for the quantitative

measurement of joint mobility6. Limited focus on thoracolumbar mobility necessitates further investigation.

Study Design: • Cross sectional prospective repeated

measures study

Participants: • Healthy, able-bodied adults (n=21)• Age= 22-60 (mean= 29.1)

Participant preparation: • Height, weight, age, sex• Limb length, wrist, elbow, ankle, knee width

Primary Objective:Validity

• Assess concurrent validity of a body-worn smartphone accelerometer for measuring thoracolumbar mobility, compared to a 3D Motion Capture System.

Secondary ObjectiveReliability

• Assess intra-rater reliability of a body-worn smartphone accelerometer for measuring thoracolumbar mobility.

Excellent correlation (ICC .986 - .989)• Flexion and right

side flexion

Moderate to excellent• Left side flexion

Poor to moderate (ICC .756)• Extension

Poor to excellent correlation (ICC .077 - .993)• Extension

Excellent correlation (ICC .957 - .996)• Flexion, right and

left side flexion

• The body-worn smartphone accelerometer demonstrated excellent validity and reliability for the measurement of thoracolumbar anterior-posterior and lateral flexion.

• Thoracolumbar left side flexion showed strong validity when compared to 3D motion capture, however did not show the clinically desired relevance for between-session reliability.

• Thoracolumbar extension showed variable validity when compared to 3D motion capture, and poor-moderate reliability between sessions

Task ICC ICC 95% CI

ICC Interpretation

Minimum Detectable Change

Extension .756 (.376, .905) Poor to moderate

6.07

Flexion .989 (.970, .996) Excellent 5.94

Left Side Flexion

.915 (.774, .967) Moderate to Excellent

4.39

Right Side Flexion

.986 (.965, .995) Excellent 4.50

Table 3: Intra-rater Reliability of Accelerometry Data

Instrumentation • Mobile phone: Samsung A5 –smart phone

• Positioned at T10• Motion Capture:

• 9-camera VICON motion capture system• Reflective markers: trunk/extremities/mobile

phone

Thoracolumbar Mobility Task: • A/P extension (4 – point stance)• A/P thoracolumbar flexion (seated)• M/L thoracolumbar flexion (standing)

Thoracolumbar Mobility Measure: • Peak A/P and M/L angle (degrees)

METHODS (cont’d)

Reflective Markers

Body-worn Smartphone

Concurrent Validity

4-point extension x10

Standing side-flexion x5 each

L/RSeated flexion x10

Intra-rater Reliability

Statistical Analysis:• Concurrent validity, intra-rater reliability:

• Intra class correlation coefficient(ICC)• <0.40 poor, 0.40-0.59 moderate, 0.60-0.79 good, ≥ 0.80 excellent• Minimal metric detectable change (MMDC)

• Concurrent validity: Bland Altman plots

RESULTS (cont’d)

ACKNOWLEDGMENTS

Intra-rater reliability of a body-worn smartphone accelerometer for measuring thoracolumbar mobile (Objective 2).• Thoracolumbar forward flexion, right side flexion, and left side flexion were all shown to be

reliable • Thoracolumbar extension was shown to not be reliable when measured between sessions

• Overall, the present findings are consistent with previous studies that examined the utilization of a mobile application for the measurement of segment mobility5.• Good – excellent - peripheral segments• Good – excellent – cervical, lumbar, trunk.

• Poorer agreement and reliability for the thoracolumbar extension task may be related to : 1) variability of task performance; 2) angular movement at thoracolumbar region for this movement; 3) efficacy of peak detection algorithm to capture peak angular change.

Limitations:• Internal validity:

• Task performance by the participant• Secure fixation of phone to the body (ie., strap method)

• External validity:• Able bodied adult population with no known musculoskeletal impairment.

Clinical Relevance:• We propose that a body worn smartphone accelerometer be utilized as an initial assessment tool for

active ROM of the thoracolumbar spine, and as an instrument to monitor ROM changes.

• Potential populations of interest to assess include: 1) musculoskeletal: aging with or without a spinal pathology (spinal deformity, degenerative joint/disc) 2) neurological: Parkinson’s, Duchenne’s muscular dystrophy, amyotrophic lateral sclerosis.

• Ontario Neurotrama Foundation

Figure 1: Tasks Performed

Figure 2: Schematic of Smartphone and VICON Output

1. Tsauo JY, Chien MY, Yang RS. Spinal performance and functional impairment in postmenopausal women with osteoporosis and osteopenia without vertebral fracture. Osteoporosis international. 2002 Jun 1;13(6):456-60.

2. Schlaich C, Minne HW, Bruckner T, Wagner G, Gebest HJ, Grunze M, Ziegler R, Leidig-Bruckner G. Reduced pulmonary function in patients with spinal osteoporotic fractures. Osteoporosis international. 1998 May 1;8(3):261-7.

3. Imagama S, Matsuyama Y, Hasegawa Y, Sakai Y, Ito Z, Ishiguro N, Hamajima N. Back muscle strength and spinal mobility are predictors of quality of life in middle-aged and elderly males. European Spine Journal. 2011 Jun 1;20(6):954-61

4. Panjabi, M. M. (1992). The stabilizing system of the spine. Part I. Function, dysfunction, adaptation, and enhancement. Journal of spinal disorders, 5, 383-383.5. Keogh, J. W., Cox, A., Anderson, S., Liew, B., Olsen, A., Schram, B., & Furness, J. (2019). Reliability and validity of clinically accessible smartphone applications to measure

joint range of motion: A systematic review. PloS one, 14(5), e02158066. Magee, D. J. (2008). Orthopedic physical assessment. St. Louis, Mo: Saunders Elsevier.7. Shrout PE, Fleiss JL. Intraclass correlations: uses in assessing rater reliability. Psychological bulletin. 1979 Mar;86(2):420.

0

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15

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25

30

35

40

45

0 2 4 6 8 10 12

Mobile Phone Angle(Degrees)3D Motion captureAngle (Degrees)

Peak - MobilePeak - VICON System

Table 2: Bland Altman Data

Figure 3: Concurrent Validity during Thoracolumbar Left Lateral Flexion

SmartphoneSession 1

Seated flexion x10

Standing side-flexion x5 each L/R

4-point extension

x10

SmartphoneSession 2

Seated flexion x10

Standing side-flexion x5 each L/R

4-point extension

x10

10 minute break

Time (seconds)

Angl

e (D

egre

es)