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C H A P T E R 4 9 Stereotactic Radiosurgery for Spine Tumors
325
References
1. F.C. Henderson, K. McCool, J. Seigle, W. Jean, W. Harter, G.J. Gagnon, Treatment of chordomas with CyberKnife: Georgetown University experience and treatment recommendations, Neurosurgery 64 (Suppl. 2) (2009) A44–A53.
2. S. Ryu, F. Fang Yin, J. Rock, J. Zhu, A. Chu, E. Kagan, L. Rogers, M. Ajlouni, M. Rosenblum,
J.H. Kim, Image-guided and intensity-modulated radiosurgery for patients with spinal
metastasis, Cancer 97 (2003) 2013–2018.
3. P.C. Gerszten, S.A. Burton, W.C. Welch, A.M. Brufsky, B.C. Lembersky, C. Ozhasoglu,
W.J. Vogel, Single-fraction radiosurgery for the treatment of spinal breast metastases, Cancer
104 (2005) 2244–2254.
4. E.L. Chang, A.S. Shiu, E. Mendel, L.A. Mathews, A. Mahajan, P.K. Allen, J.S. Weinberg,
B.W. Brown, X.S. Wang, S.Y. Woo, C. Cleeland, M.H. Maor, L.D. Rhines, Phase I/II study
of stereotactic body radiotherapy for spinal metastasis and its pattern of failure, J. Neurosurg.
Spine 7 (2007) 151–160.
5. R.J. Amdur, J. Bennett, K. Olivier, A. Wallace, C.G. Morris, C. Liu, W.M. Mendenhall, A
prospective phase II study demonstrating the potential value and limitation of radiosurgery
for spine metastases, Am. J. Clin. Onc. 32 (2009) 1–6.
6. R.L. Dodd, M.R. Ryu, P. Kamnerdsupaphon, I.C. Gibbs, S.D. Chang, J.R. Adler, CyberKnife
radiosurgery for benign intradural extramedullary spinal tumors, Neurosurgery 58 (2006)
674–685.
7. S.I. Ryu, D.H. Kim, S.D. Chang, Stereotactic radiosurgery for hemangiomas and ependymomas of the spinal cord, Neurosurg. Focus 15 (15(5)) (2003) E10.
8. S. Parikh, D.E. Heron, Fractionated radiosurgical management of intramedullary spinal cord
metastasis: a case report and review of the literature, Clin. Neurol. Neurosurg. 111 (2009)
858–861.
9. B. Wowra, S. Zausinger, C. Drexler, M. Kufeld, A. Muacevic, M. Staehler, J.C. Tonn,
CyberKnife radiosurgery for malignant spinal tumors: characterization of well-suited
patients, Spine 33 (2008) 2929–2934.
10. I.C. Gibbs, C. Patil, P.C. Gerszten, J.R. Adler Jr., S.A. Burton, Delayed radiation-induced
myelopathy after spinal radiosurgery, Neurosurgery 64 (2009) A67–A72.
The Role of Spinal Fusion and the Aging
Spine: Stenosis without Deformity
Nelson S. Saldua, Chukwuka Okafor, Eric B. Harris, and Alexander R. Vaccaro
50
k e y p o i n t s
e incidence of spinal stenosis is increasing secondary to the growing size of
the elderly patient population.
Because these patients lead more physically demanding lives and participate
more in physical leisure activities than was common for the elderly in the
past, demand for aggressive treatment of stenosis symptoms is likely.
Most of these patients can be managed nonoperatively and, of those that
require decompressive surgery, only a minority will also require fusion.
Instability is the primary indication for including fusion in operative
treatment of stenosis; it may be subtle and present prior to surgery or may be
expected secondary to the extent of decompression required.
Careful patient selection and limited use of fusion in appropriate cases results
in excellent long-term results for patients with spinal stenosis.
INTRODUCTION
Spinal stenosis is defined as any condition that results in a narrowing of the
spinal canal, nerve root canal, or intervertebral foramina. This narrowing
can occur at several locations at the same spinal level, or it can affect multiple
levels at similar locations at each level. Spinal stenosis may be due to soft
tissue impingement from a herniated intervertebral disc or an infolded ligamentum flavum, from bony processes such as osteophytes or hypertrophied
facet joints, or from a combination of these.
Spinal stenosis usually involves the lumbar spine and tends to affect
patients in the sixth or seventh decade of life. With an increase in the average
age of the patient population, the incidence of patients seeking medical care for
symptomatic spinal stenosis is also increasing. Not only are patients living longer, but also they are remaining more active in their older years, thereby making
symptoms of neurogenic claudication more apparent. Additionally, surgeries
such as total hip and knee arthroplasties are helping patients remain very active
further into their lives. Patients with lumbar spinal stenosis often complain of
symptoms consistent with neurogenic claudication, including pain, numbness,
and paresthesias in the posterolateral portions of the legs and thighs. These
symptoms are improved by activities in which the lumbar spine is held in flexion, such as leaning over a walker or shopping cart or riding a bicycle. Spinal
stenosis also occurs in the cervical and thoracic spine. The clinical presentations are different, as is the decision-making process for treatment options.
The initial treatment for symptomatic spinal stenosis is nonoperative
and consists of activity modification, oral medications, epidural steroid
injections, and physical therapy. For those cases recalcitrant to nonoperative treatment, surgery is considered. Surgical options include decompression alone, decompression with a noninstrumented fusion, decompression
with an instrumented fusion, and, recently, decompression followed by
posterior pedicle-based dynamic stabilization. Newer technologies involving minimally-invasive approaches to the spine have been developed that
indirectly improve the dimensions of the spinal canal and neuroforamina in
select cases of moderate spinal canal stenosis (interspinous process spacers).
Minimally invasive surgical (MIS) techniques have also been developed for
spinal decompression as well as fusion.
Fusion in the aging spine can be problematic, due to poor bone quality. Spinal arthrodesis should be incorporated in the surgical treatment
of spinal stenosis, either when potentially significant instability is present
preoperatively, or if postoperative instability is expected secondary to the
extent of decompression performed. The indications for spinal arthrodesis
for spinal stenosis will be discussed in this chapter, as well as the arguments
both for and against fusion. Outcomes and potential complications of spinal
arthrodesis for stenosis will also be discussed.
Basic Science
As with other segments of the spine, the etiology and specific location of
the narrowing is important when treating cervical spinal stenosis. Cervical
spinal stenosis can occur from a herniated cervical disc, an ossified posterior
longitudinal ligament, a redundant ligamentum flavum, an ossified ligamentum flavum, a hypertrophied facet joint, or from any combination of these
potentially compressive pathologies.
Stenosis in the cervical spine is of particular importance, due to the
relatively small canal diameter as compared to the caliber of the spinal cord.
Some surgeons now recommend surgical treatment for severe asymptomatic
cervical spinal stenosis for prophylaxis against paralysis, while others recommend observation.
The clinical presentation of stenosis in the cervical spine can be that of
myelopathy, radiculopathy, or both. Patients with compressive pathology
secondary to a herniated disc pressing on the spinal cord may report symptoms of myelopathy, including loss of hand dexterity and gait abnormalities. Physical exam will show signs of upper motor neuron pathology, which
can be manifested as hyperactive deep tendon reflexes, a positive Hoffmann
sign, or as a Babinski sign. If, instead, this herniated disc places pressure on
an exiting nerve root, or if the loss of intervertebral disc height causes a loss
of cross-sectional area of the neuroforamen, then the patient may exhibit
signs and symptoms of a particular nerve root radiculopathy. This will result
in motor weakness, paresthesias, and loss of deep tendon reflexes (if applicable) for that particular cervical nerve root.
Radiographically, cervical stenosis is often diagnosed using a radiographic measurement called the Pavlov ratio. This ratio is defined as the
ratio between the sagittal diameter of the spinal canal and the sagittal diameter of the vertebral body, as measured on a lateral radiograph. A ratio of
greater than 1 is considered normal, while a ratio of less than 0.8 is considered to be diagnostic for spinal stenosis. A cervical MRI can help determine
the etiology of the compression if the source is a herniated disc or a redundant ligamentum flavum. Additionally, an MRI can show any evidence of
spinal cord compression, such as a lack of cerebrospinal fluid around the
spinal cord and/or myelomalacia within the cord itself. A CT scan can be
used to diagnose bony abnormalities such as osteophytes or hypertrophied
facet joints.
329
330
P A R T V I I Surgical Treatment Modalities: Lumbar Spine
Stenosis in the Cervical Spine
CASE 1
A 63-year-old female presented to clinic with an 8-year history of worsening
neck pain radiating to her bilateral shoulders and scapulae. e pain radiated primarily down her bilateral biceps and radial forearms into the thumb
and index fingers of both hands. Additionally, she had noted a gradually
worsening weakness in her legs, with loss of balance, worsening handwriting, and difficulty buttoning buttons and manipulating small objects with
her hands. She had no bowel or bladder dysfunction. Despite nonoperative
management that included activity modification, physical therapy, and nerve
root and trigger point injections, her symptoms persisted and seemed to be
worsening.
Physical examination revealed tenderness to palpation in the cervical
paraspinal musculature as well as in the midline. She had an unsteady gait
with a positive Romberg sign. Range of motion was limited by pain, and
neck extension reproduced the pain, numbness, and tingling in her arms.
She had weakness in her right greater than left biceps, wrist extensors, and
hand intrinsics, but intact sensation throughout all dermatomes. Reflex
testing was significant for global hyperreflexia and a positive Hoffmann
sign bilaterally.
Radiographs, seen in Figure 50-1A and B, demonstrate loss of normal
cervical lordosis, severe spondylosis, and a spondylolisthesis of C4 on C5.
Sagittal and coronal MRI cuts, seen in Figure 50-2A and B, demonstrate
significant spinal stenosis, loss of normal disc height, and severe spinal cord
compression with myelomalacia.
e patient was taken to the operating room for a combined anterior
and posterior cervical decompression and fusion. Discectomies and interbody fusion were performed with allograft spacers and an anterior plate
at C4-5, C5-6, and C6-7. is portion of the procedure restored normal
lordosis and addressed the anterior pathology, including reduction of the
spondylolisthesis at C4-5. e posterior procedure included laminectomy
from C3 to C7 with screw and rod fixation from C3 to C7 as well (Figure
50-3A and B).
Postoperatively, the patient did well, with complete resolution of her
arm pain. At last visit, her gait and balance were steadily improving, with
overall improved function compared to preoperatively.
F IG UR E 5 0- 1 A and B. AP and lateral
radiographs demonstrating severe spondylotic
changes and a 4 mm anterolisthesis of C4
on C5.
F IG UR E 5 0 -2 A and B. MRI
showing severe stenosis from C3 to C7
with cord compression at multiple levels
and signal change within the spinal cord.
4 mm
4
5
6
A
B
A
B
C H A P T E R 5 0 e Role of Spinal Fusion and the Aging Spine: Stenosis without Deformity
F IG UR E 50 -3 A and B. AP and
lateral postoperative radiographs. Note
the restoration of natural cervical lordosis
accomplished through multiple anterior
discectomies. Posterior decompression
and fusion creates additional space for the
spinal cord and provides increased stability
for fusion.
331
A
B
Clinical Practice Guidlines
Cervical radiculopathy can be successfully treated nonoperatively with
activity modification, oral medications, and selective nerve root block
injections. Operative indications include symptoms that are recalcitrant
to nonoperative treatment as well as development of myelopathy. The
natural history of cervical myelopathy is that of a stepwise progression
of symptoms alternating with periods of nonprogressive neurological
symptoms.
The location of the compressive pathology in cervical stenosis is important, as it dictates the operative approach. Cervical stenosis due to a central or moderate-sized posterolateral cervical herniated nucleus pulposus is
best treated with an anterior approach, in order to adequately remove the
compressive pathology. This anterior cervical discectomy is typically combined with a fusion. Fusion is achieved with or without instrumentation,
consisting of an anterior plate and screws. Anterior cervical discectomy and
fusion (ACDF) has been described with good results without the use of
instrumentation. An anterior cervical discectomy (ACD) without fusion
is rarely performed today, and is almost never performed for multilevel
disease. Discectomy without fusion has been reported in a prospective,
randomized trial to be equivalent to ACDF for the treatment of cervical
radiculopathy.
been reported to result in good relief of neck and arm pain as well as a 76%
rate of return to work.
in other case series to be associated with worsening of preexisting cervical
myelopathy in 3.3% of cases.
out fusion was also reported by Nandoe Tewarie et al in a retrospective
review of 102 patients evaluated up to 18 years after surgery.
alone has been shown to be successful in the treatment of cervical myeloradiculopathy, the possibility of worsening of symptoms, combined with
the difficulty of revision of anterior cervical surgery, makes this a possible
yet unattractive surgical option.
If the compressive pathology is secondary to redundant ligamentum
flavum, hypertrophied facet joints, or other posterior pathology, then a
posterior approach allows the surgeon to directly decompress the offending
agent. A posterior-only approach is only indicated if neutral or lordotic alignment of the cervical spine is maintained. A kyphotic deformity in the cervical spine often mandates an anterior approach to restore the normal cervical
1
For the treatment of myelopathy, ACD without fusion has
2
However, ACD without fusion has been shown
3
Worsening of symptoms after ACD with-
4
While ACD
sagittal alignment. Decompression from a posterior approach consists of
laminotomy, laminectomy, or laminoplasty. Removal of significant portions
of the facet joints should be avoided in order to avoid causing iatrogenic
postlaminectomy cervical kyphosis. Raynor et al reported a cadaveric study
comparing the potential degrees of instability on biomechanical testing of
intact specimens, and following 50% facetectomy, and 70% facetectomy. The
conclusion of this study was the recommendation that a facetectomy should
involve less than 50% of the facet joint in the absence of fusion, in order to
avoid spinal instability.
5
Postlaminectomy kyphosis after posterior cervical
decompression alone is common when there is evidence of hypermobility
on preoperative flexion-extension radiographs. A cervical fusion should be
considered after posterior decompression if:
A neutral plain lateral radiograph demonstrates a kyphotic cervical
alignment.
e decompression involves removal of more than 50% of the facet
joint.
e supraspinous and interspinous ligaments are incompetent or iat-
rogenically injured.
Instability is seen on preoperative static radiographs or dynamic flex-
ion-extension radiographs.
For multiple-level posterior cervical spinal cord compression, laminoplasty is another option. In this procedure, the space available for the spinal
cord is increased by cutting the affected lamina on one side and scoring the
contralateral lamina. The posterior elements are then “booked” open, utilizing the scored side as a hinge, and held open with suture, structural grafts/
spacers, or plate and screws. With the newly increased space available for
the spinal cord, the spinal cord can float away from the vertebral body. This
treatment plan only works in cases in which a neutral or lordotic curve of the
cervical spine is maintained. In a kyphotic cervical spine, the spinal cord will
remain draped over the vertebral bodies regardless of the increased space
posterior to the cord.
A combined anterior and posterior approach may be needed for
kyphotic deformities with spinal stenosis and for multiple level disease.
Posterior instrumentation and fusion is usually warranted when performing
three or more cervical corpectomies or when doing four or more cervical
discectomies.
332
P A R T V I I Surgical Treatment Modalities: Lumbar Spine
Basic Science
Thoracic stenosis is encountered by the surgeon much less frequently than
stenosis of the cervical or lumbar spine. As in the cervical spine, thoracic
stenosis is defined when the canal diameter is less than 10 mm. The compressive pathology is most often a herniated intervertebral disc, with the
majority of the disc herniations being paracentral. Other etiologies, such as
tumors, are possible. Thoracic stenosis can occur from a progressive kyphosis seen with multiple adjacent insufficiency fractures.
Thoracic stenosis presents with some similar signs and symptoms to
cervical stenosis. Since the brachial plexus has already exited the spinal cord,
Stenosis in the Thoracic Spine
CASE 2
A 58-year-old woman with no significant past medical history presented
to an outside hospital with progressive bilateral lower extremity weakness,
right greater than left, and decreased sensation below the nipple line. In addition, she reported 5 out of 10 pain in the midthoracic area, urinary retention,
mild constipation, and an inability to bear weight. Emergency department
records indicated that she had twisted her back one week prior to admission and complained of subsequent onset of these progressive symptoms. Of
note, several months prior to presentation, the patient noted irritation and a
possible mass in the upper outer quadrant of her right breast. Radiographs
obtained at an outside hospital demonstrated a pathologic fracture of her
sixth thoracic vertebrae. She was transferred to our facility for evaluation
and for further radiologic and immunopathic workup for presumed metastatic breast cancer to the thoracic spine.
Physical exam at the time of admission was notable for a 2 × 2 cm
purple nodule on her right breast with induration and no discharge. Tenderness to palpation over the cervical spine was noted. Neurological exam
demonstrated weakness in bilateral lower extremities with 2/5 hip flexors, 4/5 quadriceps, 1/5 tibialis anterior, 1/5 extensor hallucis longus,
and 2.5gastrocnemius; upper extremity strength was 5/5. Sensation was
the patients with thoracic stenosis do not complain of the hand dexterity problems associated with cervical stenosis. They can exhibit signs and
symptoms of thoracic level radiculopathy, lower extremity upper motor neuron dysfunction, or gait abnormalities.
Clinical Practice Guidelines
Operative indications for stenosis in the thoracic spine are similar to those
in the cervical spine: symptoms recalcitrant to nonoperative measures and
cases in which myelopathy develops.
decreased bilaterally; clonus was present, particularly on the right; Babinski sign was absent; and rectal tone was decreased. e patient was afebrile
with stable vital signs, and admission labs were within normal limits.
e patient had a CT scan of her spine that demonstrated pathologic
fractures of T5 and T6 and lytic lesions at multiple spinal levels with bony
destruction, predominantly from T3 to T6, with encroachment upon the
adjacent central canal and neural foramen (Figure 50-4). ese findings
were most suggestive of metastatic lesions. MRI of her spine demonstrated
metastatic disease with multilevel involvement and posterior epidural
extension in T5 and T6 resulting in spinal cord compression (Figure 50-5).
e patient underwent a T3 to T6 laminectomy for extradural tumor,
posterolateral fusion of T2 to T10, and open biopsy of the presumed metastatic lesion. Pathologic examination was consistent with metaplastic breast
cancer (Figure 50-6). e patient tolerated the procedure well without
complication. At the time of discharge from inpatient rehabilitation, lower
extremity motor strength had improved to 3/5, and sensation had improved
as well. Bladder function did not return and a Foley catheter was maintained.
e neurogenic bowel responded well to enema, Dulcolax, Colace, and senna.
e patient was transferred to the oncology service for further evaluation and treatment of her metastatic breast cancer.
F IG UR E 50 - 4 CT scan of the thoracic spine showing multilevel lytic
lesions with bony destruction, predominantly from T3 to T6, with encroachment of the adjacent central canal and neural foramen. These are most suggestive of metastatic lesions.
F IG UR E 5 0 -5 MRI scan of the thoracic spine showing extensive multi-
level metastatic involvement, most prominent in the upper thoracic spine, with
posterior epidural extension at T5 and T6 compressing the spinal cord.
C H A P T E R 5 0 e Role of Spinal Fusion and the Aging Spine: Stenosis without Deformity
F IG UR E 5 0 -6 Lateral x-ray of thoracic spine, status post T3-T6 laminectomy
and T2-T10 fusion, with pedicle screws and rods in stable positioning.
333
Treatment for thoracic stenosis is usually limited to decompression
alone. The decision on whether to use an anterior, posterior, or transthoracic approach depends on the source of the compressive pathology. Fusion,
historically, has rarely been indicated due to the greater inherent stability
of the thoracic spine afforded by the rib cage and sternum. Palumbo et al
described a retrospective review of 12 patients treated for thoracic stenosis.
All were treated with a decompression alone, without fusion. Although the
majority of their patients improved with regard to pain, ambulation, and
neurological function, five patients exhibited early deterioration of symptoms due to recurrent stenosis, deformity/instability, or both. The authors
imply that a decompression at the thoracolumbar junction was more prone
to instability.
6
When surgically treating spinal stenosis in the thoracic spine, fusion
should be considered in cases where:
Anterior column support is lost, such as in severe compression or burst
fractures or with tumor resections.
e decompression involves the thoracolumbar junction.
Instability is seen on preoperative static radiographs or dynamic flex-
ion-extension radiographs.
Basic Science
Spinal stenosis is most frequently encountered in the lumbar spine. It typically affects patients in their sixth or seventh decade of life. As a normal
age-related change of the intervertebral disc, the nucleus pulposus itself
loses water content, which in turn leads to a loss of disc height. This loss
of water may result in increased motion at the vertebral body–disc interface, leading to increased motion at the level of the facet joint. This excess
motion at the facet joint may lead to facet joint arthrosis and hypertrophy. Finally, the loss of intervertebral disc height translates to decreased
cross-sectional area of the neural foramina as well as redundancy of the
ligamentum flavum. All of these age-related changes contribute to lumbar
spinal stenosis.
The clinical syndrome of lumbar spinal stenosis is that of neurogenic
claudication. Patients often report lower extremity pain that is worsened
with activity, but lessened when the patient is allowed to assume a position
in which the lumbar spine is flexed. Activities such as riding a bicycle or
leaning over a shopping cart are better tolerated by patients with lumbar stenosis, because they are performed with the lumbar spine in a flexed position.
The radiographic workup of lumbar stenosis begins with plain radiographs of the lumbar spine. Radiographs should be scrutinized for osteophytes, malalignment, facet hypertrophy or any other abornormalities
that could potentially decrease the space available for the neural elements.
Flexion-extension radiographs are needed to determine the presence of
instability. The presence of any preoperative instability necessitates a spinal
fusion. A MRI can be useful in determining the specific location (paracentral, lateral recess, or foraminal) of the stenosis. A CT myelogram is useful
in localizing the specific area of the compressive lesion, but this has been
largely supplanted by MRI.
Clinical Practice Guidelines
Controversy exists in the literature with regard to whether a spinal fusion
should be added to decompression. Decompression alone without fusion
has been reported to treat lumbar spinal stenosis with good results. However, other reports in the literature, primarily those including patients with
instability, report better clinical outcomes with addition of spinal fusion.
Yone et al reported on a group of 34 patients with lumbar spinal ste-
7
nosis.
Of this group, 17 patients had radiographic spinal instability as
described by Posner. Ten patients underwent decompression and fusion,
and the remaining seven underwent decompression alone. The decompression-alone patients had significantly worse Japanese Orthopaedic
Association back scores. Still others report no difference in clinical outcomes for patients treated with decompression alone and decompression
plus fusion.
decompression and fusion, with good results.
technical demands present in cervical laminoplasty.
8, 9
Expansive laminoplasty has been reported as an alternative to lumbar
10
This procedure shares the
334
P A R T V I I Surgical Treatment Modalities: Lumbar Spine
Stenosis in the Lumbar Spine
CASE 3
An active 90-year-old man was referred to the spine surgery clinic with
a long history of worsening bilateral buttock pain and decreased walking
tolerance. He was otherwise in excellent health, but noted a burning pain
in his buttocks with radiation down the posterior and lateral thighs after
ambulating more than about 50 yards. e pain quickly improved with rest,
and would not occur if he had a shopping cart to lean on while ambulating. Descending stairs or inclines would aggravate symptoms but ascending
stairs would not. He had been evaluated by the vascular surgery service and
was not found to have vascular insufficiency. Despite an intensive program
of physical therapy focusing on core strengthening, flexibility, and cardiovascular fitness his symptoms persisted. Interventions by the pain management
service, including epidural steroid injections, had been unsuccessful.
F IG UR E 50 -7 A, AP x-ray of lumbar spine
showing multilevel spondylosis with a degenerative
scoliosis and mild lateral listhesis at multiple levels.
B, Lateral view showing severe disc collapse and listhesis at multiple levels.
Physical examination was relatively unremarkable, with normal
strength throughout all muscle groups and intact sensation in all dermatomes. Gait was steady and neurological testing was unremarkable.
Radiographs, seen in Figures 50-7A and B, demonstrate advanced
degenerative changes, with significant disc height loss, large disc osteophyte
complexes, and facet hypertrophy from L2 to L5. Sagittal and coronal MR
images seen in Figure 50-8A and B show severe central, lateral recess, and
foraminal stenosis, with increased fluid in the zygapophyseal joints and
buckling of the ligamentum flavum.
e patient was taken to the operating room for a L2 to L5 decompression and posterolateral instrumented fusion. Postoperative images are
shown in Figure 50-9A and B. At last follow-up, the patient had returned
to his premorbid level of functioning, with complete resolution of his claudication symptoms and no postoperative pain.
F IG UR E 5 0- 8 A, Sagittal MR
image depicting moderate to severe
central stenosis from L2 to S1. B, Coronal MRI cut showing lateral recess and
foraminal stenosis accompanied by
facet hypertrophy and broad-based disc
bulging.
A
A
B
B