Computer Model Analysis of Cervical Lateral Function
for Symmetric and Asymmetric/Symptomatic Subject Groups
Emily Wandell, B.S. 1, Nicholas Beechnau, B.S. 1, William Smits, B.S. 1, Seungik Baek, Ph.D. 1, Jongeun Choi, Ph. D. 1, Mark de Zee, Ph.D.2,3, Tamara Reid Bush, Ph.D. 1
1
2
Department of Mechanical Engineering, Michigan State University, East Lansing, MI 48824
Center for Sensory-Motor Interaction, Dept. of Health Science and Technology, Aalborg University, Denmark
3 AnyBody Research Group, Institute of Mechanical Engineering, Aalborg University, Denmark
RESEARCH PURPOSE
PROCEDURE
Background
1. Screening
This study used Kinematic Data
from 2 Subject Groups
(Classified by Physicians as those
with Symmetric Motion Patterns
& Asymmetric Patterns exhibiting
Neck Pain) to drive a Cervical
Computer Model (See Figure 1).
Two examiners screened
subjects by performing a
standard palpatory motion
test of cervical lateral flexion.
(See Figure 2)
Figure 1
Hypothesis
Motivation
To move toward an era of evidenced base medicine,
it will be necessary to develop computer models that are more representative
of the human body.
Figure 2
No agreement, subjects not
invited to participate in the
Kinematic test
ANYBODY Cervical Model
Kinematic patterns for the symmetric subject group
will yield differences in muscle activities (predicted by the compute model)
as compared to the asymmetric/pain group.
Examiner Agreement
Subjects Classified as:
1)Symmetric
(10 Subjects)
2)Asymmetric/Pain
(Self Marked Score of 4
or higher on a Pain Scale)
(9 Subjects)
3. Kinematic Test/ Data Collection
RESULTS
Strong Trend: Symmetric Subjects had Higher
Levels of Muscle Activity (See Table 1)
Statistics (t-test at 95% confidence level):
•Trapezius Activity had Significant
Difference (p=0.03) Between Groups
• Other Muscle Groups (Sternocleidomastoid,
Longus Colli, Scalenus Medius, & Scalenus
Posterior) had Low p Values & with a Larger
Sample May Show Significant Differences
Figure 3
•Subjects had markers placed on their
head & sternum.
•Examiners performed the same
lateral motions used in screening
•Kinematic data was collected using
5-camera Qualisys system
(See Figure 3).
Purpose
Evaluate Potential of Cervical Computer Model (AnyBody)
to Assist in Correlating Objective Measures (Kinematic Data)
& Clinical Findings (Physician Classification).
Figure 4
4. Output 3D Kinematic Data:
•Position of neck given by 3 Angles of
Neck Motion over the data collection time.
(See Figure 4)
RELEVANCE
1) 1 Challenge: (in Biomechanical Assessments of humans)
Large Range of Variability!
*Model can Provide Estimations for Mainstream Populations*
A model increasingly more
representative of the human cervical region
can be used in combination with
biomedical/clinical assessments to facilitate
the move toward evidence-based strategies!
5) AnyBody Model
Thus, a Model can Help Refine Studies
Higher Activity for Symmetric Subjects might be Expected
*Because as a Group had a Larger Range of Primary
Motion*
IMPLICATIONS
2) 2 Challenge: controlling specific parameters.
*Predictive Scenarios could be studied with a computer model to shed
insight into how parameters affect the kinematics or the muscle forces
associated with an activity*
CONCLUSIONS
•3-D Movement Patterns for each
subject was inputted into the Cervical
Model (AnyBody) & used to drive
the model.
•By solving the muscle recruitment
problem, the model provided a % of
max muscle force for muscle groups Figure 5
(Left) Experimental Data Collection
used in the activity
(Right) Model Driven with Actual Kinematic Data