Scoliosis and
Kyphosis
Scoliosis and
Kyphosis
Definition
Scoliosis is a postural deformity of the
spine resulting in a lateral (coronal)
deviation, or curve.
Scoliosis is commonly associated with
rotation of the vertebral bodies located
within the curve.
It affects between 3% and 30% of the
population, with its incidence increasing with
age.
The scoliotic curve may be congenital, appearing
during infancy (infantile scoliosis), or develop in
childhood (juvenile scoliosis), adolescence
(adolescent scoliosis), or adulthood (degenerative
scoliosis).
When the diagnosis of scoliosis is made in an
adult patient, the curve should be defined as
adult onset (usually degenerative) or adult
presenting (most commonly an idiopathic
adolescent curve that was not previously
diagnosed).
Scoliosis can result from congenital,
degenerative, disease-related, or
idiopathic causes.
An idiopathic etiology of scoliosis is more
common than scoliosis due to other
causes, such as degenerative disc disease
and spondylosis, congenital malformation
of the vertebrae, tumor, neuromuscular
disease, or connective tissue disease.
Kyphosis is defined as a sagittal deviation in spinal
alignment, or backward curve exceeding normal
values.
Normal kyphosis in the thoracic spine varies between
20 and 40 degrees.
Pathologic kyphosis occurs in association with
structural changes in the spine due to pathology
such as osteoporotic compression fractures, tumor,
or Scheuermann's disease (juvenile kyphosis).
It is caused by the resulting wedge deformity of the
vertebral bodies.
Symptoms
Scoliosis
The symptoms produced by scoliosis relate to
the etiology, location, and severity of the
curve.
The curve itself often does not produce
symptoms or complaints, particularly a curve
that does not exceed 20 degrees.
When scoliosis is severe, pain and cosmetic
deformities occur.
Deformity, such as humping of the back,
asymmetric shoulder or hip height, or asymmetry
of breast size or waist contour may produce
psychosocial symptoms such as low self-esteem,
anxiety, and depression.
These may be the presenting complaints.
Curves that exceed 60 degrees begin to affect
other systems.
They can produce shortness of breath due to
restrictive lung disease; weakness, pain,
paresthesia; or hypesthesia due to compression
or impingement of nerve roots; and impaired
activity tolerance due to increased energy costs
for maintaining trunk stability.
Severe lumbar curves commonly produce low
back pain, whereas severe thoracic curvature
often results in psychosocial symptoms.
Kyphosis
Complaints relate to the degree and location of
the kyphos.
Intermittent aching back pain and stiffness are
the most usual presenting complaints and are
most prominent at the apex of the kyphos. Pain
and stiffness may be most severe when the
patient is leaning forward.
A compensatory increase in lumbar lordosis, with
or without spondylolysis, may be present and
associated with low back pain.
Cardiopulmonary compromise, though unusual,
can also develop in severe cases, causing
shortness of breath, fatigue, and poor activity
tolerance.
Physical Examination
Scoliosis:
Minor curves are difficult to detect on inspection of the
patient.
An easy way to detect a subtle thoracic or lumbar curve is to
drop a plumb line from the occiput, or C7 spinous process,
and inspect the spine for lateral deviations from this line.
Have the patient bend forward, because the rotation
associated with scoliosis is most easily seen in the forward
flexed position.
Asymmetry of the back contour in this position is due to
vertebral body or rib rotation and may be quantified.
A trunk rotation angle of 7 degrees roughly corresponds to
a coronal curve of 20 degrees.
Subtle indicators that can be sought on physical
examination include apparent (not actual) unequal breast
size, asymmetry of the waist fold contour, or unequal iliac
crest and shoulder height.
Scoliosis should be suspected when café au lait spots (often
associated with neurofibromatosis) or a leg-length
discrepancy exceeding 2.2 cm is present.
Thorough serial assessments are advisable every 6 to 12
months.
These assessments usually include x-rays and should
focus on the degree of curvature, location and extent
of the curve, degree of rotation, degree of skeletal
maturity, correctibility of the curve, height, vital
capacity, and expiratory pulmonary function tests.
Patients with degenerative scoliosis should be
examined for neurologic deficits.
Lower extremity strength, sensation, and reflexes
should also be checked when the curvature exceeds
40 degrees or when the patient complains of
weakness, paresthesias, or decreased sensation
regardless of the etiology of the scoliosis.
A full evaluation of a scoliotic curve necessitates
identification of the etiology of the curve for
optimal treatment and prognostication.
Curves may be idiopathic (juvenile, adolescent),
functional (muscle spasm, posture), congenital
(vertebral malformation), or degenerative or
paralytic (motor unit disease).
Scoliosis should be treated in the context of a
patient's global status, and identifying underlying
or idiopathic causes of the curve allows care to be
provided within the context of the patient's overall
health.
Kyphosis
Increased thoracic kyphos results in a forward
displacement of the head and neck and a
compensatory increase in lumbar lordosis.
These are apparent on inspection.
The rounding of the back will not fully correct with
trunk extension in a prone position, but the degree to
which the curve reverses should be noted.
Thoracolumbar and lumbar kyphoses are less readily
appreciated on inspection.
The clinician should note any prominence of the
spinous processes, which indicates lower spine
kyphosis.
Associated scoliosis should be sought and will be
present in about one third of patients.
Restricted trunk extension results from either
deformity or pain.
Tenderness to palpation may be elicited over the
spinous processes.
Tightness of the hamstring and pectoralis
muscles is common.
A neurologic examination should be performed
when the patient complains of weakness, sensory
changes, or gait abnormalities.
Vital capacity, peak flow, and other expiratory
respiratory parameters should be performed
when the kyphosis exceeds 40 to 50 degrees.
Functional Limitations
The functional limitations related to scoliosis and
kyphosis result from the loss of spinal motion.
A kyphosis related restriction in upward gaze may
affect driving and cause difficulty with lying prone or
swimming in a prone position.
Loss of shoulder range of motion, particularly forward
flexion and abduction, may result from restricted
scapular excursion over the thorax.
This can interfere with overhead activities of daily
living.
Pain can result in limited sitting, standing,
or walking tolerance.
The disruption of spinal balance that
occurs will displace the center of gravity,
particularly with severe kyphosis.
This increases the energy costs for
standing and ambulation.
It can also impair balance.
With severe deformity, cardiopulmonary
compromise may decrease endurance.
If the patient perceives cosmetic
deformities as severe, social isolation can
result.
Diagnostic Studies
Standing anteroposterior (AP) and lateral x-rays are
useful in the evaluation of scoliosis and kyphosis.
Bending or supine radiographs are not usually done
but can help to determine the flexibility or
correctability of the curve.
X-rays can reveal congenital abnormalities of the
vertebral body that cause spinal imbalance (block,
bar, butterfly vertebrae), evidence of Scheuermann's
disease (endplate fluting), or the lateral vertebral
body wedging that is characteristic of idiopathic
scoliosis.
Measurement of the scoliotic curve on plain films is done by
either the Cobb or Risser method.
The most common measurement, the Cobb angle, is determined
by the intersection of two lines drawn perpendicular to the
vertebral endplates that represent the maximal deviation of the
spine.
Plain films also allow assessment of vertebral body rotation and
the growth centers in the ilium, vertebrae, and humerus.
The degree of vertebral body rotation is gauged by the deviation
from the midline of either the spinous process or pedicles.
Rotation is graded 0 (no rotation) to 4 (rotation of 90 degrees or
more).
Epiphyseal closure can sometimes be assessed by
plain films.
Closure of the growth plates proceeds in a
cephalad manner.
Since vertebral growth plates are not consistently
demonstrated on plain films, the iliac crest is a
useful site for assessing spine growth status.
This is Risser's sign, which is graded 0 (no
mineralization) to 5 (fusion of the growth plate).
Magnetic resonance imaging (MRI), computerized
tomography (CT), and nuclear medicine scans are
indicated for specific purposes, such as identifying a
neurofibroma or diastomatomyelia.
If a neurologic deficit is present, MRI or CT should be
performed to delineate the lesion.
Electrodiagnostic studies are a useful adjunct to
these tests for grading the severity of the lesion and
prognostication.
If surgery is being considered, preoperative MRI or
CT myelogram is indicated.
Bone scans are helpful to exclude discitis or
tumor as the cause of pain or spinal deformity.
Pulmonary function testing, particularly volume
and expiratory studies, should be performed
when curves exceed 60 degrees.
Treatment
In all patients, regardless of age, it is important to
identify curves that are likely to be progressive.
Curves that are large (degree of curvature), closely
packed (spanning a relatively small spinal segment),
related to congenital vertebral body malformation, and
very rotated or occur in the immature spine require
more aggressive intervention.
In general, scoliotic curves less than 20 degrees and
kyphotic curves less than 40 degrees are observed
through serial assessment.
NSAIDs/COX-2 inhibitors or analgesics may be used for
pain management.
Transcutaneous electrical nerve stimulation
(TENS) may also be used to manage pain.
If the scoliosis exceeds 20 degrees or the
kyphosis exceeds 40 degrees, assess for bracing
or surgery.
The treatment goal for idiopathic curves is to limit
progression of the scoliosis or kyphosis and
maintain full activity, independence, and comfort.
This is best done with patient education, exercise,
and bracing.
Rehabilitation
Exercise is beneficial for general well-being, flexibility, and
to improve posture.
There is no clear evidence that exercise is a disease-
modifying intervention for
idiopathic scoliosis.
Kyphosis may improve with cervicothoracic extension
exercise; pelvic tilt to reduce lumbar lordosis; and
stretching/strengthening exercise of the hamstring, hip
flexor, and pectoralis muscles.
Exercise, particularly spinal extension, abdominal
strengthening, and hamstring stretch, is also helpful to
reduce back pain.
Bracing is an important part of the rehabilitation
intervention.
There is no consensus regarding recommended brace wear-
time per day; recommendations range between 8 and 23
hours of daily wear.
Some correction of the curvature may take place with
conscientious use of the orthosis, although the goal of
orthotic treatment is to reduce pain and limit progression of
the curve.
The most common brace selection is a body jacket
thoracolumbosacral orthosis (TLSO) such as the Boston or
Denver brace.
High thoracic and cervical curves and kyphotic curves may
require a Milwaukee cervicothoracolumbosacral orthosis
(CTLSO).
Bracing for idiopathic curves in a growing child or
adolescent is maintained until spinal growth centers fuse.
When a TLSO body jacket or corset is used to decrease pain
and improve posture for patients with degenerative
scoliosis, wear time depends on symptoms.
For scoliosis associated with neuromuscular diseases,
bracing is often withheld if the patient is ambulatory.
When a body jacket is provided, an abdominal
window is needed to allow respiratory excursion.
Contoured or custom molded seating systems
that align and support the trunk are useful.
These allow the child, adolescent, or adult to
maintain an upright posture while seated,
improving head control and hand function.
Procedures
There are no invasive procedures indicated for
the treatment of scoliosis or kyphosis.
Surgery
Surgical procedures attempt to restore spinal balance.
The goal of surgery is to stabilize the spine through
correction or control of the deformity. Improved
cosmesis is a secondary goal.
Restoring lumbar lordosis is important.
Indications for surgical correction of scoliosis or
kyphosis include progressive deformity, instability,
progressive or new neurologic deficit, and
cardiopulmonary compromise.
Surgical stabilization of the spine for scoliosis
associated with neuromuscular disease is
performed earlier than for curves due to other
causes.
Pain, even when refractory to conservative
management, is a controversial indication for
surgery.
Inability to use a brace, and severe cosmetic
deformity may be relative indications for surgery
in specific instances.
Scoliosis
Surgery addresses the coronal and rotational
deformities by derotation and, less commonly,
distraction.
Any spinal instability is eliminated through
compression or bony fusion.
Spine surgery may be complemented by rib resection
in an attempt to improve appearance.
The postoperative management of surgical patients
varies according to the etiology of the curve, age of
the patient, and specifics of the surgery.
Some patients may be placed in a cast or body
jacket to immobilize the operated segment until
bony fusion occurs.
Cotrel-Dubbousset instrumentation and its
various modifications that derotate the spine
commonly do not require fusion, immobilization,
or rib resection.
Other surgical procedures such as osteotomy or
laminectomy are done as appropriate.
Kyphosis
Various surgical approaches have been
used, but anterior plus posterior
instrumentation with fusion currently
provides the highest success rate for
lasting correction and pain relief.
Potential Disease
Complications
Complications of scoliosis or kyphosis result from
the structural and degenerative changes that
occur in the spine, along with secondary tightness
or restriction due to soft tissue shortening.
An increased incidence of spondylosis, facet
arthropathy, spondylolisthesis, and spondylolysis
is associated with large curves and correlates
with the angle and rotation at the curve apex.
Such degenerative changes related to the curve
are the most common causes of pain, but
scoliosis can also produce discogenic pain.
Foraminal, recess, or canal stenosis can occur with
resulting neurologic compromise.
Root entrapment usually occurs on the concave side
of the curve (rarely both convex and concave sides).
Cauda equina compression has also been reported.
Lumbar spinal stenosis due to scoliosis can
sometimes be differentiated from other types of
stenosis because the disease and symptoms are
more structural than positional.
Patients often will not report relief of symptoms
when sitting.
Restrictive lung disease may occur as a
complication of scoliotic curves exceeding 40
degrees or kyphosis in excess of 50 degrees, and
cor pulmonale can complicate severe kyphosis or
scoliotic curves in excess of 110 degrees.
Potential Treatment
Complications
Most treatment complications relate to surgery or bracing.
Reported complications of bracing include skin breakdown;
dermatitis due to an allergy to the orthotic material; hyperhidrosis;
cutaneous infection; gastroesophageal reflux disease (GERD);
esophagitis; altered gastrointestinal motility; and psychosocial
complications including low self-esteem, altered body image, and
depression.
Surgery may cause vascular or neurologic injury, pseudarthrosis,
infection, graft donor site pain, progressive pelvic obliquity, painful
degenerative changes in the segment adjacent to the level of
fusion, instability, hardware prominence or failure, and
thromboembolism.
Hardware complications include slippage of anchoring hooks,
bending or fracture of a rod, wire pull-out, and migration of the
hardware.
Progression of the curve is possible despite surgical fixation.
In the growing adolescent the crankshaft phenomenon—
progressive deformity resulting from continued growth of the
anterior spine after posterior arthrodesis—may occur.
This results in further loss of spinal balance, but is usually not
problematic.
The patient with degenerative scoliosis who has undergone
otherwise successful surgery may continue to experience pain
or restricted mobility.
Exercise related complications are less common but include
overuse conditions of the soft tissues (tendinitis, bursitis,
sprain, strain). Complications following NSAID therapy are
possible, particularly in the gastric, renal, and hepatic systems.