Central Cord Syndrome
November, 2006
Central Cord Syndrome (CCS) is an incomplete injury to the
cervical cord resulting in more extensive motor weakness in the upper
extremities than the lower extremities. The mechanism of injury occurs
from a hyperextension injury with pre-existent osteophytic (abnormal
bony outgrowth) spurs, without damage to the vertebral column.
Mechanism and Causes of Injury
CCS occurs typically in patients with hyperextension injuries
where the spinal cord is squeezed or pinched between anterior cervical
spondylotic bone spurs and the posterior intraspinal canal ligament, the
ligamentum flavum. The ligamentum flavum is a strong ligament that
connects the laminae of the vertebrae. It serves to protect the neural
elements and the spinal cord and stabilize the spine so that excessive
motion between the vertebral bodies does not occur.
The injury occurs as a result of anterior and posterior
compression of the spinal cord, leading to edema, hemorrhage or ischemia
to the central portion of the spinal cord. The site of most injuries is
in the mid-to-lower cervical cord. Due to the anatomical lamination of
the corticospinal tract with the arm fibers medially, and the leg fibers
laterally, the arms are affected more so than the legs, resulting in a
disproportionate motor impairment.
Symptoms
Patients are typically left with motor weakness of the upper
extremities and lesser involvement of the lower extremities. A varying
degree of sensory loss below the level of the lesion and bladder
symptoms (urinary retention) may both occur.
Incidence
This syndrome more commonly affects patients age 50 and older who
have sustained a cervical hyperextension injury.
CCS may occur in patients of any age and is seen in athletes who
present with not only hyperextension injuries to their neck but
associated ruptured disc(s) with anterior cord compression.
CCS affects males more frequently than females.
Diagnosis
Evaluation of the patient includes a complete history, a thorough
neurological exam, MRI and CT of the cervical spine, and cervical spine
x-rays including supervised flexion and extension x-rays.
- Magnetic resonance imaging (MRI): A
diagnostic test that produces three-dimensional images of body
structures using powerful magnets and computer technology; can show
direct evidence of spinal cord impingement from bone, disc, or hematoma.
- Computed
tomography scan (CT or CAT scan): A diagnostic image created after a
computer reads x-rays; can show the shape and size of the spinal canal,
its contents, and the structures around it.
- X-ray:
Application of radiation to produce a film or picture of a part of the
body can show the structure of the vertebrae and the outline of the
joints. X-rays of the spine delineate fractures and dislocations, as
well as the degree and extent of spondylitic changes. Flexion/extension
views assist in evaluation of ligamentous stability.
Surgical Treatment
Acute surgical intervention is not usually necessary unless there
is significant cord compression. Prior to the CT-MRI era, surgical
intervention was thought to be more harmful because of the risk of
injuring a swollen cervical cord and worsening the deficit. However,
with advanced imaging technology such as CT and MRI, patients with
compression of the spinal cord secondary to traumatic herniated discs
and other lesions can be quickly diagnosed and surgically decompressed.
In cases with anterior bony ridges and spinal canal narrowing secondary
to ligamentous thickening and or stenosis, acute surgery is usually not
performed until the patient has made maximum recovery. Reassessment at
that time may lead to surgery depending on the underlying cause. If
there is significant motor weakness after a period of recovery, or
neurological deterioration or spinal instability, then surgical
intervention may be considered.
Nonsurgical Treatment
Nonsurgical treatment consists of immobilization of the neck with
a cervical orthosis, steroids unless contraindicated, and
rehabilitation with physical and occupational therapy.
Outcome
Many patients with CCS make spontaneous recovery of motor
function while others experience considerable recovery in the first six
weeks post injury.
If the underlying cause is edema, recovery may occur relatively
soon after an initial phase of motor paralysis or pareses. Leg function
usually returns first, followed by bladder control and then arm
function. Hand movement and finger dexterity improves last. If the
central lesion is caused by hemorrhage or ischemia, then recovery is
less likely and the prognosis is more devastating.
The prognosis for CCS in younger patients is favorable. Within a
short time, a majority of younger patients recover and regain the
ability to ambulate and perform daily living activities. However, in
elderly patients the prognosis is not as favorable, with or without
surgical intervention.