Postural Stability in Cervical Spinal Myelopathy

Veterans are at heightened risk of developing cervical spondylotic myelopathy (CSM) from
rigors of military service. Diagnosis of CSM involves a set of clinical findings and is
confirmed by imaging the spine.

Gait impairment and disturbances of stance control are hallmarks of CSM and are a consequence
of abnormalities in proprioception due to dorsal column tract damage of the spine. Currently,
gait and balance deficits rely on clinical level assessments and judgement for detection. An
objective measure of posturography has the benefit of: a) quantifying balance-related
disability in CSM, b) facilitating structure-functional assessments in CSM, and c)
quantifying the degree surgical interventions affect posturography and recovery of function
in CSM.

Objective and sensitive means for assessing balance and posturography exist, but are not
routinely incorporated in diagnosis or functional tracking of progress after interventions
such as surgery. A barrier may be accessibility of posturography and ease of assessments. The
Virtual Environment TBI Screen (VETS) was devised using Army Rapid Innovation Development
funding to objectively assess balance and posturography in a cost effective, but sensitive
manner. VETS involves virtual environments and computerized posturography and is proving to
be a sensitive system facilitating diagnosis, treatment, and mitigation of balance
dysfunction associated with mTBI.

The working hypothesis is VETS testing will enhance clinical judgements regarding CSM. The
SPiRE is designed to provide data critical to a more extensive program of research
incorporating posturography into treatment and rehabilitation of CSM.

First, a limited comparative study of standing balance will be conducted of 20 Veterans being
evaluated for cervical spine surgery to treat CSM and 20 otherwise healthy Veterans. Second,
posturography of the Veterans undergoing surgery to treat CSM will be tracked during their
scheduled follow up visits to determine the degree VETS scores are affected by surgery and to
track recovery from CSM.

Patients in the CSM group will be selected based on clinical criteria. Veterans in the
control group will be recruited from the Syracuse Veterans Affairs Medical Center (SVAMC) and
surrounding community.

For VETS testing, the Veteran will stand directly on a firm surface or foam pad placed on top
of a Wii Balance Board (WBB). There are six conditions manipulating surface (firm or foam
surface) and visual input (eyes open viewing a static scene, eyes closed, and eyes open
viewing a dynamic visual scene). The primary measure is the center of pressure (COP) sway
area. These 6 conditions allow for an assessment of generalized vs specific deficits in COP
sway area considering proprioception, dependence of visual input and visuo-proprioceptive
integration.

AIM 1A: Determine whether and to what degree balance is altered in CSM. The degree of COP
sway will be compared between CSM and controls in the six conditions comprising VETS testing.

AIM 1B: Determine whether VETS enhances sensitivity and selectivity in the diagnosis of CSM.
Composite measures of balance will be related to clinical assessment tools and their
relationship with MRI.

AIM 2: Evaluate the VETS scores after surgery to treat CSM. The degree of COP sway area under
the 6 conditions will be compared before surgery, 2 weeks, 6 weeks and 6 months after surgery
(corresponding with post-operative clinical assessments).

The ultimate goal is to validate and incorporate objective balance testing into routine
assessment for CSM to aid in disambiguating CSM, to improve functional assessments of
recovery, and to aid in evaluations of different treatment and rehabilitation strategies in
CSM for the Veteran population.

Inclusion Criteria:

Patients in the CSM group will be selected based on clinical criteria. Inclusion criteria
for the CSM group are:

- symptoms of myelopathy in upper and lower extremities and stenosis of the cervical
spine demonstrated by MRI or myelography

- lower extremity muscle strength of 4 as quantified by manual muscle test (MMT) 36 or
above

- ability to stand without support with eyes closed for 30 s or more

- Veterans in the control group will be recruited from the SVAMC and surrounding
community using printed advertisements

Exclusion Criteria:

Exclusion criteria for all study participants are:

- presence of lower extremity or lumbar spine disease

- peripheral neuropathy

- history of other neurological disorder

- inability to stand in an upright position with both feet together and eyes closed

- Although the SVAMC population is predominately Caucasian and male, every effort will
be made to recruit minorities and women

- The proposed study will neither target for recruitment nor will the investigators
exclude pregnant women