MEASURING INTER-VERTEBRAL MOTION

IN-VIVO WITH QUANTITATIVE FLUOROSCOPY

Fiona Mellor BSc (Hons). PhD Student.Research Radiographer/Associate Clinical Doctoral Research Fellow

Institute for Musculoskeletal Research and Clinical Implementation

Anglo-European College of Chiropractic/Bournemouth University

U.K.

e: imrci.fmellor@aecc.ac.uk

How and Why: with examples of normative and patient data

Objectives Place Bournemouth U.K. on the map Importance of inter-vertebral

measurements Using QF to measure inter-vertebral

motionLumbar and Cervical spineMeasurement parameters

Case study Current research

http://www.aecc.ac.uk/

Why measure intervertebral motion?

TreatmentRehabilitation

ResearchIn vitroIn vivo

DisabilityAmerican Medical Association: AOMSI

DiagnosisPseudarthrosisMechanical low back pain: passive

and active motion, palpation tests“Instability”

Past – Present - Future

In vitro analysis

f

Def

orm

atio

n (d

egre

es)

lax

normal

Neutral zone

Elastic zone

Failure

Plastic zone

Almost all changes to the force (time)/deformation curve occur in the elastic zone.

The neutral zone, taken as the slope of its initial

climb under 2 kg of force, is largely linear.

2 kg

Neutral Zone Theory

Quantitative Fluoroscopy

Biomechanical

Hypothesis

In vivo Passive and active Lumbar and cervical spine Measurements include:

Rotation Translation Instantaneous centres of rotation

Quantitative Fluoroscopy

The Bigger Picture Are there differences in the measurable

spine kinematics of people with CNSLBP compared with those without?  If so..

Are the factors in people with CNSLBP identifiable?  If so...

Do changes in them predict outcome?  If so..

Can we change them?

Quantitative FluoroscopyAcquisition Image Analysis Output

Image analysis

Vertebral rotation

Inter-vertebral rotation

Flexion Extension(mm)

Translation

Instantaneous Centre’s of Rotation (ICR’s)

Clinical example ICR’s in a degenerate spine

Case study: Female age 49

30 year history of non specific LBP which resolved from 2002 – 2010, then recurred after an RTA in March 2010. Prone pressure test (L5) positive. Original investigations (1993 x-ray then MRI) revealed grade 1 L5/S1 spondylolisthesis and L-S disc degeneration.

Case study: Female age 49

Case study: Female age 49

Left Right

L1/2 4.69 2.88

L2/3 4.46 4

L3/4 3.83 3.69

L4/5 5.59 5.59

L5/S1 1.95 1.95

Flex ExtL1/2 2.13 4.33L2/3 3.59 3.79L3/4 4.55 2.14L4/5 5.1 3.2L5/S1 7.24 9.02

Rotation

Case study: Female age 49 L5 Grade II spondylolisthesis with little or no

degenerative change or other anomaly. Reduced extension rotational motion in upper lumbar segments with increased motion at the spondylolisthesis level in both flexion and extension. Normal directions and no laxity detected. However, total translational (flexion + extension) at L5-S1 was 4.9mm which, taking error into account, may border on abnormal.

Case study: Female age 49 Treatment:

Patient wanted to avoid surgery. Extension mobilisation at the upper lumbar levels, 4 treatments over 2 months.

Home rehab (foam roll)Maintain normal activity

Outcome:Pain score reduced from 6/10 to 2/10Normal activity resumed apart from fast

swimming (aggravates extension)

QF research at AECC1. Characteristics of lumbar spine intervertebral

kinematics in healthy adults and their reproducibility over time

N = 269 normative study N = 108 intra subject repeatability study Protocol:

Trunk swingAge 21-71yearsRecumbent passive AND weight-bearingCoronal OR sagittal orientations

Weight-bearing acquisition

Passive Vs Active motion

With kind permission from Orthokinematics.com

Healthy Passive Vs Active motion

Healthy recumbent passive flexionIn

ter-

vert

ebra

l ang

le (

o)

Time (15 frames = 1 second)

Healthy weight-bearing flexion

Time (15 frames = 1 second)

Inte

r-ve

rteb

ral a

ngle

(o)

QF Studies at AECC2. Effects of manipulation of the cervical

spine on inter-vertebral motion patterns and patient reported outcomes

N = 60 (30 patients, 30 matched healthy volunteers).

Baseline and 6 week Active guided motion

Cervical spine acquisition

Cervical spine rotationin a patient with whiplash

Flexion

Whiplash (flexion)Normal IAR location(Amevo et al, 1992) (n=46)

C1-2

C2-3

C3-4

C4-5

C5-6

C6-7

PhD. Mid-lumbar inter-vertebral motion in participants with and without chronic non

specific low back pain

N = 80. (40 each group) Matched cohort for age, gender and BMI.

Chronic Mechanical LBP > 3/12 duration Hip swing protocol 40o in each direction L2-L5

Outline Hypothesis: There will be a greater

prevalence of ‘abnormal’ motion in those with CNSLBP than healthy controls.

Abnormal defined as fixations (RoM < 3o) and increased laxity (Neutral Zone proxy) in first 10 degrees of trunk motion

Analysis: Sensitivity and Specificity of abnormal motion

Results to date: Demographics

Patients Controls

N = 39 36

Age years (SD)

36.2 (8.4) 35.2 (8.4)

% male 56% (n=22) 53% (n=19)

BMI (SD) 24.8 (2.9) 24.5 (2.2)

Left

Left

Preliminary results

Fiona Mellor

PhD study

Results

Preliminary results

Fiona Mellor

PhD study

Accuracy and ReliabilityMotion

parameterPlane of motion

Accuracy against

calibration model (root

mean square)

Inter observer reliability

(root mean square)

Intra observer reliability (SEM)

Intra subject variability

(root mean square)

Lumbar spine passive recumbent rotation (3)

Coronal (left/right)

0.32o 1.86 o N/A (TBC) 2.75 o - 2.91 o

Sagittal (flex/ext)

0.52 o 1.94 o N/A (TBC) N/A (TBC)

Lumbar spine passive recumbent translation

Flexion 0.6mm (10) 1.674mm (2) 1.427mm (2) N/A (TBC)

Extension 0.79mm (10) 1.736mm (2) 1.958mm (2) N/A (TBC)

Cervical spine active controlled motion (1)

Flexion 0.21 o N/A (TBC) 0.52 o N/A (TBC)

Extension 0.34 o N/A (TBC) 1.08 o N/A (TBC)

Radiation DoseAbsorbed dose cGy.cm2

(SD)

Calculated Effective dose mSv (SD)

QF recumbent lumbar spine coronal and sagittal

613 (150) 0.561 (0.154)

QF weight-bearing lumbar spine coronal and sagittal

662.9 (171) 0.77 (0.18)

AP + Lateral lumbar spine radiograph

460 0.39 -1.2

Absorbed dose cGy.cm2 (SD)

Calculated Effective dose mSv (SD)

QF cervical spine sagittal

42.8 (9) 0.01 (0.003)

Lateral cervical radiograph

0.012

Estimated effective dose (mSv)

Transatlantic flight 0.07

CT head 1.4

UK annual background dose (average) 2.7

USA annual background dose (average) 6.2

Thanks for listening

References Breen, A. (2011). Quantitative fluoroscopy and the mechanics of the lumbar spine. Department of

Medical Physics, Open University. MSc. Breen, A., Muggleton, J., Mellor, F. (2006). "An objective spinal motion imaging assessment

(OSMIA): reliability, accuracy and exposure data." BMC Musculoskeletal Disorders 7(1): 1-10. Hart, D., Hillier, M.A., Wall, B.F. (2005). Doses to patients from medical x-ray examinations in the

UK. Review, National Radiation Protection Board (NRPB). Health Protection Agency (HPA). (2008). "Typical effective doses, equivalent periods of natural

background radiation and lifetime fatal cancer risks from diagnostic medical exposures." Retrieved 13.03, 2012, from http://www.hpa.org.uk/web/HPAweb&HPAwebStandard/HPAweb_C/1195733826941.

Health Protection Agency (HPA). (2009). "Recommended national reference doses for individual radiographs on adult patients - 2000 review." Retrieved 31.1.2012, from http://www.hpa.org.uk/web/HPAweb&HPAwebStandard/HPAweb_C/1195733771087.

HPA. (2010). "Patient Dose information." Retrieved 24.08, 2010, from http://www.hpa.org.uk/web/HPAweb&HPAwebStandard/HPAweb_C/1195733826941.

Mellor, F. E., J. M. Muggleton, et al. (2009). "Midlumbar Lateral Flexion Stability Measured in Healthy Volunteers by In Vivo Fluoroscopy." Spine 34(22): E811-E817.

Mellor, F. E., P. Thomas, et al. (2012). "Radiation dose from quantitative fluoroscopy for investigating in vivo kinematics of the lumbar spine; compared to lumbar spine radiographs with suggestions for further dose reduction." British Journal of Radiology submitted.

Van Loon, I., F. E. Mellor, et al. (2012). "Accuracy and repeatability of sagittal translation of lumbar vertebrae in vitro and in vivo using continuous quantitative fluoroscopy." Clinical Chiropractic Submitted.

Questions and Comments?

Fiona Mellor

E: imrci.fmellor@aecc.ac.uk

Acknowledgements:National Institute of Health. Clinical Academic Training Fellowship.Bournemouth University Santander travel award.Anglo-European College of ChiropracticOrthokinematicsProfessor Alan Breen and the team at IMRCIProfessor Nat Ordway and the team at SUNY