Disorders and Diseases of the Spine
and of sciatica is 30% to 40%. The cause of the low back pain in
approximately 90% of the patients is related to disc degeneration.
-
History taking in the patient with low back pain.
Low back pain is common and the most frequent causes are benign and
self-limiting. Still, it is extremely important to “rule out” the
dangerous causes. Generally this can be accomplished with a thorough
history. The common patient with back pain is between the ages of 20
and 50 and has no signs or symptoms of systemic illness. Be on the
alert for back pain in the young and the old. A thorough review of
systems should include questions about associated fever, sweats, weight
loss, or change in bowel or bladder. -
Physical examination.
The physical examination begins with observing the body position chosen
by the patient (patients with acute sciatica may choose to avoid
sitting in a slouched position as this places extra pressure on the
impinged nerve root). The back should be exposed and one should note if
there is any redness or warmth. Note range of motion of the spine. A
straight leg raise is generally performed with the patient in the
supine position, but can be done first with the patient in the seated
position when the patient’s physical symptoms seem disingenuous. The
lower legs and feet should be exposed in order to test distal strength,
sensation, and reflexes. -
Causes of low back pain.
Low back pain is a symptom, not a disease, and the pathologic basis of
the pain frequently lies outside the spine. There are many causes,
which are classified in Table 12-1.-
Vascular back pain. Aneurysms or peripheral vascular disease may give rise to backache or symptoms resembling sciatica.
-
Neurogenic back pain.
Tension, irritation, and compression of lumbar nerves and roots may
cause pain down one or both legs. Lesions anywhere along the central
nervous system, particularly of the spine, may present with back and
leg pain. -
Viscerogenic back pain
may be derived from disorders of the organs in the lesser abdominal
sac, the pelvis, or the retroperitoneal structures such as the pancreas
and kidneys. -
Psychogenic back pain. Clouding and confusion of the clinical picture by emotional overtones may be seen. A pure psychogenic component is rare.
-
Spondylogenic back pain. Common conditions causing spondylogenic back pain are outlined in Table 12-2.TABLE 12-1 Classification of Low Back Pain Causes
Vascular
Neurogenic
Viscerogenic
Psychogenic
SpondylogenicTABLE 12-2 Common Conditions Causing Spondylogenic Back Pain- Disc degeneration
- Spondylolisthesis
- Trauma
Myofascial sprains/strains
Fractures - Infection (bacterial tuberculosis)
- Tumor (benign, malignant, metastatic)
- Rheumatologic
Ankylosing spondylitis/spondyloarthropathy
Fibrositis/fibromyalgia - Metabolic
Osteoporosis
Osteomalacia
Paget disease
P.204-
Disc degeneration
is by far the most common cause of back pain. Disc degeneration may
occur anywhere along the spine and produce neck pain, thoracic spine
pain, or lumbar or low back pain. Disc degeneration may be associated
with nerve root irritation, which would then result in radicular leg
pain. The nerve root irritation or compression may be due to an acute
disc herniation or impingement by bony stenosis or a combination of
soft-tissue and bony impingement.-
Anatomy. The
spine provides stability and a central axis for the limbs that are
attached. The spine has to move, to transmit weight, and to protect the
spinal cord. When the spine is viewed from the side, the thoracic spine
is concave forward (kyphosis) and the cervical and lumbar regions are
concave backward (lordosis). -
Vertebral components
-
Each segment of the vertebral column
transmits weight through the vertebral body anteriorly and the facet
joints posteriorly. Between adjacent bodies are the intervertebral
discs, which are firmly attached to the vertebrae. The disc consists of
an outer annulus fibrosis, which is made up of concentric layers of
fibrous tissue. It surrounds and contains a central avascular nucleus
pulposus, which consists of a hydrophilic gel made of protein,
polysaccharide, collagen fibrils, sparsely chondroid cells, and water
(88%). The spinal cord and caudal equina are found within the spinal
canal. At each intervertebral level, nerve roots leave the canal
through the intervertebral foramina. -
A functional spinal unit or motion
segment consists of two adjacent vertebrae and the intervertebral disc.
It forms a three-joint complex with the disc in front and two facet
joints posteriorly. The facet joints, like other joints in the body,
have capsules, ligaments, muscles, nerves, and vessels. Changes in one
joint affect the other two. Narrowing of the disc space, therefore, may
result in malalignment of the facet joints and, with time, lead to
wear-and-tear degenerative arthritic changes in those joints.
-
-
Pathology.
Normal aging is associated with a gradual dehydration of the disc. The
nucleus pulposus becomes desiccated and the annulus fibrosus develops
fissures parallel to the vertebral end plates running mainly
posteriorly. Small herniations of nuclear material may squeeze through
the annular fissures and may also penetrate the vertebral end plates to
produce Schmorl nodes. If the nuclear material squeezes
P.205
against
the nerve, it may produce nerve root irritation. The flattening and
collapse of the disc results in osteophytes along the vertebral bodies.
Malalignment and displacement of the facet joints is an inevitable
consequence of disc space collapse, leading to osteophytes that may
narrow the lateral or subarticular recess of the spinal canal or the
intervertebral foramina. This narrowing of the spinal canal or of the
intervertebral neural foramina is called spinal stenosis. -
Disc degeneration without nerve root irritation. There are three patterns of low back pain associated with disc degeneration: acute incapacitating backache, which may occur a few times in a person’s life and not be a regular problem; recurrent aggravating backache, which is the most common type and is associated with regular periods of recurrence and remission of back pain; and chronic persisting backache, which is the most difficult to treat and the patients have constant disabling back pain.
-
The back pain associated with disc
degeneration is mechanical in nature. It is aggravated or brought on by
activity and relieved by rest. There may be a referred component of
back pain into the legs, but this is usually down the back of the legs
and rarely goes beyond the knee. The low back pain may be due to
periods of hard work, prolonged standing or walking, or prolonged
sitting in one position. The peak incidence of back pain in the general
population is in the 40s and 50s. This is the time when the discs have
collapsed and there is relative instability at the motion segment. The
natural history, however, is for the spine to stiffen up with increased
fibrosus around the facet joints and the discs. As the patient gets
older, the physical demands become less and the spine becomes stiffer;
the incidence of back pain, therefore, declines beyond the 60s. -
Patients who give a history of fever,
weight loss, malaise, night and rest pain, morning stiffness, and
colicky pain should be carefully evaluated for the possibilities of
infection, tumor, spondyloarthropathy, or viscerogenic back pain.
-
-
Disc degeneration with root irritation
-
Nerve root irritation and compression may be due to an acute disc herniation or may be associated with spinal stenosis.
Acute disc herniation results in “sciatica.” Essentially, this involves
severe, incapacitating pain that radiates from the back down the leg.
It may be associated with paresthesia, neurologic symptoms, or motor
sensory or reflex changes. The pain may be constant and is frequently
aggravated by coughing, sneezing, and straining. Intradiscal pressure
is increased in a bending and sitting position, especially if lifting
is performed, therefore increasing the amount of pain. The pain may be
lessened by lying down. -
The most frequent sites of disc herniation
are in the spinal canal, resulting in impingement of the traversing
nerve root. Less common disc herniation may be laterally in the
foramen, resulting in impingement of the existing nerve root. The leg
pain or sciatica is accompanied by signs of nerve root tension, which
can be diagnosed by a straight-leg raising test, bowstring sign, or
Lasegue’s test. -
In spinal stenosis,
the leg pain or radicular pain is brought on by prolonged walking or
standing (neurogenic claudication). The pain may be associated with
paresthesia and is relieved by sitting or stooping. There are few
physical findings or neurologic deficits unless the condition has been
present for a long time and is advanced. Neurogenic claudication
associated with spinal stenosis should be distinguished from vascular
claudication caused by peripheral vascular disease.TABLE 12-3 Neurology of the Lower ExtremityRoot Muscles Sensation Reflex L2 Hip flexion Anterior thigh (proximal) None L3 Knee extension (quadriceps) Anterior thigh (distal) Patellar L4 Anterior tibialis Medial leg Patellar L5 Extensor hallucis longus Lateral leg and dorsum of foot None S1 Gastrocsoleus peroneus
longus and brevisLateral foot Achilles
-
-
Neurology of the lower extremities.
The nerve roots leaving the spine at each segmental level may be
affected by acute disc herniations, bony foraminal stenosis, or a
stenosis associated with both soft-tissue and bony compression. The
nerve root may be affected within the central spinal canal, in the
subarticular recess, or in the intervertebral foramen. The nerve root
traversing the motion segment or the exiting nerve root may be
affected. It is important to correlate the patient’s symptoms and
physical findings with the abnormalities seen on radiographs, magnetic
resonance imaging (MRI) scans, and computed tomography (CT) studies. It
is important, therefore, to have knowledge of the nerve roots and their
distal enervation. The main nerve roots are listed in Table 12-3. -
Imaging studies (Table 12-4)
-
Radiographs
may appear normal or demonstrate disc space narrowing, osteophyte
formation, or instability on lateral flexion and extension views. There
is no clear-cut correlation between low back pain and the presence of
disc space narrowing on plain radiographs (1).TABLE 12-4 “Red Flags” in Patients Presenting with Back Pain (Typically Indications for Imaging)Concern for malignancy
Age >50
Previous history of cancer
Unexplained weight loss
Pain unrelieved by bed rest
Pain lasting >1 mo
Failure to improve within 1 mo
Acute trauma
Concern for Infection
Erythrocyte sedimentation rate >20 mm
Intravenous (IV) drug abuse
Urinary tract infection
Skin infection
Fever
Concern for compression fracture
Corticosteroid use
Age >70
Age >50
Concern for neurologic problem
Sciatica
New bowel or bladder incontinence -
Myelograms
are invasive and are less commonly used. They may be used in
combination with CT scans in patients who have complex problems or who
have had multiple surgeries. Myelograms should be ordered either by or
with direct consultation of the treating surgeon. -
CT scans are generally helpful when MRI scans cannot be obtained. They give better detail of the bone.
-
MRI scans of the lumbar spine are noninvasive and an excellent way to evaluate the compromise of neural structures.
-
Bone scans of
the spine and pelvis are useful if tumor and infection are suspected,
although these abnormalities can also be picked up easily on an MRI
scan. -
Indications for imaging acutely in low back pain.
Acute imaging is indicated only if there is a history of trauma,
concern for infection or tumor, presence of a neurologic deficit,
suspicion for osteoporosis, and acute fracture.
P.207 -
P.206 -
-
Spondylolisthesis.
Spondylolisthesis is the forward slippage of one vertebra on another.
Spondylolysis is the presence of a bony defect of the pars
interarticularis, which may result in spondylolisthesis. The incidence
of spondylolysis/spondylolisthesis in the asymptomatic population is 3%
to 5%. It is unclear how common this entity results in back pain in
adult patients. What is clear is that adolescents who present with back
pain are suffering from this entity at a much higher level and they
must be followed much more closely due to the fear of the slippage
progressing. This is especially true if they are gymnasts or performing
other activities which place extra stress upon their posterior-lateral
elements.-
Classification
-
Congenital
-
Isthmic
-
Traumatic
-
Pathologic
-
Degenerative
-
-
Congenital spondylolisthesis
is a congenital deficiency of the facets. Isthmic spondylolisthesis is
the typical defect in the pars interarticularis allowing forward
slippage of the vertebrae. It may be related to an acute fracture, a
fatigue fracture, or an elongation or attenuation of an intact pars
interarticularis. Traumatic spondylolisthesis is an acute fracture of
the pedicle, lamina, or facet. Pathologic spondylolisthesis is an
attenuation of the pedicle caused by weakness of bone (e.g.,
osteogenesis imperfecta). The most common type of spondylolisthesis is degenerative spondylolisthesis. -
The Meyerding grading system
is used to indicate the percentage of displacement of the superior
vertebral body on the inferior vertebral body as follows: grade I, 0%
to 25%; grade II, 25% to 50%; grade III, 50% to 75%; grade IV, 75% to
100%; grade V, greater than 100% spondyloloptosis. -
Etiology. The
initial onset of a lesion occurs at approximately 8 years of age.
History of minor trauma may exist. The onset of symptoms coincides
closely with either the adolescent growth spurt or repetitive athletic
activity. It is thought to originate in a stress or fatigue fracture.
The shear stresses are greater on the pars interarticularis when the
spine is extended. Such stresses are seen with certain activities
(e.g., back walkovers in gymnastics, carrying heavy backpacks, heavy
lifting). -
Clinical findings in isthmic spondylolisthesis.
Patients may be asymptomatic, but most patients have low back pain
during the adolescent growth spurt. A few patients do have nerve root
or radicular pain in the lower extremities. Hamstring tightness or
spasm is
P.208
commonly found in symptomatic patients. A palpable step-off may be felt at the level of the slip. -
Anteroposterior and lateral radiographs
are helpful in making the diagnosis to demonstrate the slip of
spondylolisthesis. An undisplaced spondylolysis is best seen on the
oblique views of the lumbar spine. The “Scottie dog” sign describes the
appearance of the facet joints and pars interarticularis on the oblique
radiographs. The “Scottie dog’s” neck representing the pars is broken
in isthmic spondylolysis. For the young patient with back pain felt to
be due to spondylolisthesis, it is important to institute activity
modification and follow closely. If symptoms persist, then consultation
is advised. There is no urgency about surgical treatment of
spondylolisthesis unless serial radiographs have demonstrated
progression of the slip or if there is significant neurologic
impairment.
-
-
-
Treatment of acute, nonradicular low back pain
-
Initial treatment includes activity
modification. This includes bed rest not to exceed 2 days, although
activity as tolerated appears equally efficacious (2,3). Also, use of nonsteroidal anti-inflammatory drugs (NSAIDs) has demonstrated benefit (4). The addition of short duration treatment (several days) with muscle spasm medication appears beneficial (5). The exact role for physical therapy is unclear although aerobic exercise has a positive correlation with spine health (6).
Manual therapy (such as chiropractic, osteopathic, or physical therapy
applied manual techniques) appears to shorten the duration and
intensity of symptoms (7). There is no role for
surgery in the treatment of acute, low back pain. The use of guidelines
appears to have some benefit, but has had variable use to date (8). -
Treatment of acute sciatica.
Initial treatment is directed at making the symptoms tolerable for the
patient until the natural history of improvement occurs. This involves
use of NSAIDs or other medications as necessary. The exception to this
approach is cauda equina syndrome (CES) with bowel and/or bladder
dysfunction where surgical decompression is required within 24 to 48
hours of onset or there is low probability of neurologic recovery (9,10).
Progressive neurologic deterioration without CES is a relative
indication for expedited surgery. There is recent evidence that
transforaminal epidural steroid injections (ESI) may avoid surgery in a
number of patients (11). If unacceptable pain
persists at 6 to 12 weeks, then surgical treatment is of benefit.
Previously the Weber study has been misquoted as indicating that there
are no differences between surgical and nonsurgical management, yet
appropriate analysis of this classic study demonstrates the benefit of
surgery (12,13). -
Treatment of lumbar spinal stenosis. Neurogenic claudication is a chronic disease that appears to be slowly but irregularly progressive (14).
Treatment modalities used have included NSAIDs, physical therapy,
epidural steroids, and decompression. The data to support the efficacy
of nonoperative treatment is limited. The benefit of lumbar
decompression appears sound (15). In the
particular circumstance of lumbar stenosis due to single level
degenerative spondylolisthesis, there is good data indicating the
benefit of decompression and fusion (16). There
is much debate about the benefit of spinal instrumentation in
combination with fusion. Successful fusion provides better clinical
results than pseudarthrosis (17). Spinal instrumentation increases the fusion rate. -
Treatment of chronic low back pain. This is a very controversial subject (18).
The first difficulty is diagnosis of the pain generator. There are many
confounding variables such as workers compensation, smoking (19),
litigation, diabetes, and psychological issues. The pain generator
could be disk degeneration, facet degeneration, chemically mediated
nerve irritation, or other as yet undefined mechanisms (20).
Since these patients are such a variable cohort, conflicting data arise
form studies with highly variable entry criteria. There is great
variability in recommended nonoperative treatment with highly variable
results. There is also variability in surgical treatment
recommendations ranging from uninstrumented
P.209
posterior
fusion, instrumented posterior fusion, various interbody fusion
techniques, and minimally invasive techniques using these same
strategies to the newest technologies for motion preservation such as
artificial disc replacement or posterior ligamentous tethering devices.
There is a prospective randomized trial from Sweden demonstrating the
benefit of surgery compared to nonoperative treatment (21).
The benefit of spinal instrumentation in this study was not profound.
The availability of rhBMP-2 has led to excellent results and avoided
harvesting autogenous iliac crest bone graft, when used in anterior
stand alone one level fusion (22). So controversy remains and will persist.
-
-
Scoliosis
-
Scoliosis is a side to side curvature
when the spine is viewed in the coronal plane. This deformity may be
flexible and reactive or fixed and structural. In the former, there is
no structural change and the deformity is correctable. There are three
causes: postural, compensatory (to another curve, pelvic tilt, or short leg), and sciatic.
In structural scoliosis, there is a three-dimensional deformity. The
vertebrae are deformed and are rotated toward each other. The resulting
rotation of all the attachments and appendages of the vertebrae, such
as ribs and processes, results in asymmetry of the body, waistline, and
paravertebral prominences, as well as shoulder elevation. -
The broad categories of structural scoliosis are as follows:
-
Idiopathic (infantile, juvenile and adolescent)
-
Osteopathic (congenital)
-
Neuropathic (cerebral palsy, poliomyelitis)
-
Myopathic (muscular dystrophies)
-
Connective tissue (Marfan’s, Ehlers Danlos)
-
Neurofibromatosis
-
-
Scoliosis is also seen in other disease processes such as spinal cord injuries, infections, metabolic disorders, and tumors.
-
Curve types
-
A structural curve is a segment of the spine with lateral curvature lacking normal flexibility.
-
A primary curve
is the first or earliest of several curves to appear. A compensatory
curve is a curve above or below a major curve. It may progress to be a
fixed or secondary curve.
-
-
Adolescent idiopathic scoliosis.
This is the most common type and has no known cause. It presents around
puberty and may progress until skeletal maturity has been reached.
There may be one, two, or three curves occurring most frequently in the
thoracic and lumbar spine.-
Risk factors for progression of adolescent idiopathic scoliosis.
Progression is related to the size of the curve, the area of the spine
involved, and the physiologic age of a patient. Large thoracic curves
progress to a greater degree than single lumbar or thoracolumbar
curves. The younger the skeletal age, the more likely the curve
progression. Progression is less likely to progress in boys than in
girls.
-
-
Clinical findings.
Presentation of a painless deformity occurs between 10 and 15 years of
age. If severe and persistent pain is present, the possibility of a
tumor (most commonly osteoid osteoma), sciatic scoliosis, or
spondylolysis should be considered. The rotational deformity is more
noticeable on forward flexion, creating a paravertebral prominence.
Other clinical features include shoulder elevation, neckline prominence
on side asymmetric waistline, or prominent hip. The term spinal imbalance
refers to the head or the trunk being off center with respect to the
pelvis. Clinically, this can best be measured by dropping a plumb line
from the base of the skull. Any deviation of the line from the gluteal
cleft measures the amount of spinal imbalance to the left or right. A
complete history and physical examination is performed to exclude other
causes of scoliosis.P.210-
The history
of a patient with spinal deformity should include age when the
deformity was first noted, the perinatal history, and the family
history of scoliosis. In children and adolescents, scoliosis is
generally not painful. If persistent pain is present, appropriate
diagnostic tests should be performed to exclude bony or spinal tumor,
herniated discs, or other abnormalities. The patient is examined,
undraped, except for undershorts, and asymmetries in the shoulder,
scapular, waistline, and pelvic region are identified. The balance of
the thoracic area over the pelvis is assessed. The C7 plumb line test
is used to evaluate the balance of the head over the pelvis and the
range of motion of the spine in flexion and extension. Side bending is
also noted. The patient should also be observed from the side for
evaluation of kyphosis or lordosis. The forward bend test is useful to
identify areas of asymmetry in the paravertebral areas. Prominence of
the scapula or rib on one side is called a “rib hump.” A complete
neurologic examination should be performed. Pubertal stages in girls
and boys are assessed. Leg length from the anterior-superior iliac
spine to the medial malleoli is measured. The lower extremities are
evaluated for deformities or contractures.
-
-
Radiographic evaluation
includes full length views of the entire spine in a standing position.
The angle of curvature is measured. The size of the curve is measured
by the COBB method. The upper and lower
end vertebrae are identified, and perpendicular lines are erected to
their transverse axis. The intersection of the perpendicular lines is
the COBB angle. Radiographs are also used to evaluate the degree of
skeletal maturity. The Risser classification
evaluates the degree of ossification of the iliac epiphysis. This
measures the degree of skeletal maturity. There are five grades. -
Treatment.
The natural history of these curves varies. Some curves remain the
same, others progress, and yet others progress relentlessly. The goal
of treatment is to prevent curve progression. Serial radiographs are
obtained every 4 months until skeletal maturity. Risk of curve
progression is greatest in younger patients with larger curves.-
Braces are
indicated in the growing patient with curves of 20 to 40 degrees.
Braces have distinct limitations. They brace the body and torso and
indirectly exert forces on the spine (e.g., pressure pads on ribs
attached to convex vertebrae) and are used to prevent further curve
progression rather than straighten the curvature. -
Surgery is
indicated for curves greater than 40 degrees in the skeletally immature
patient who has failed conservative treatment. Anterior or posterior
instrumentation is performed to correct the curvature and stabilize the
spine. Bone grafting is added to achieve spinal fusion.
-
-
-
Kyphosis
-
The gentle posterior curvature of the
normal thoracic spine when viewed from the side (sagittal plane) is
kyphosis. The normal range is 20 to 40 degrees. Excessive posterior
curvature beyond normal is also referred to as kyphosis. -
Adolescent round back
(postural kyphosis) is a flexible deformity evenly distributed
throughout the thoracic spine and without any structural changes. It
may be due to lax ligaments or poor muscle tone and is associated with
other postural defects such as flat feet. Treatment is the same as for
Scheuermann kyphosis. -
Structural kyphosis
refers to stiff curves with vertebral wedging. It is seen in
Scheuermann disease and osteoporosis (round back of old age).
Congenital kyphosis has underlying structural change and usually has a
local sharp posterior angulation, also termed kyphus, which may also be
seen in fracture or infection. -
Classification
-
Scheuermann disease (adolescent kyphosis). This is a growth disorder of uncertain etiology involving the vertebral growth plates.
-
Clinical findings
-
There are two types based on location. The classic form
of Scheuermann disease occurs in the thoracic spine. Criteria for
diagnosis include wedging of at least 5 degrees of three adjacent
vertebrae. End plates are irregular. This type is twice as common in
girls as boys. The painless deformity is usually first noticed by
parents. Pain may occur but is a rare symptom. Onset is usually around
10 years of age. A distinct hump at the apex of the kyphosis is
frequently noted. The deformity is accentuated on forward flexion and
its rigidity prevents correction on extension. -
The lumbar form
of Scheuermann disease occurs more commonly in teenaged males. They
present with chronic mechanical lumbar pain, which may improve with
maturation. -
Kyphosis is a change in the alignment of
a segment of the spine in the sagittal (side view) plane that increases
the normal posterior convex angulation. The COBB method of measuring
kyphosis is used to measure angulation greater than 45 to 50 degrees in
the thoracic spine.
-
-
-
Treatment. A progressive kyphosis of the thoracic spine in a skeletally immature patient is treated in a Milwaukee brace
until maturity. Surgery is reserved for select cases with curves
greater than 75 degrees that have pain or are unresponsive to bracing.
Lumbar Scheuermann disease is not responsive to bracing. It is treated
by exercises and anti-inflammatories if painful.
-
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