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Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy 147
T10
T11
T12
FIGURE 16-3
n
The sympathetic chain, with plexuses, typically lies at each level parallel to the
spine—bilaterally from T2 to T12. The stellate (or inferior cervicothoracic) ganglion typically lies from C6 to T2. Ipsilateral Horner syndrome (ptosis, myosis or
pinpoint pupils, enophthalmos, and facial anhydrosis) can ensue if damage to
the chain occurs.
n
The diaphragm consists of flattened muscle, central tendon, and two crura
inserting on the anterior longitudinal ligament of the thoracolumbar spine. Its
takedown is often needed to allow access down to L2. Retropleural dissection
can avoid the need for incision and repair, and it still affords a retroperitoneal
path caudally.
n
The artery of Adamkiewicz (great anterior radiculomedullary artery) typically
(≈70%) originates from a left-sided intercostal or lumbar segmental artery (T9L2). Traditionally, ligation has been thought to potentially cause spinal cord
ischemia. Recent evidence suggests that up to three levels of bilateral embolization or ligation may be performed without ischemia or neurologic demise
(Murakami et al, 2010).
Positioning
n
A double-lumen endotracheal tube is inserted.
n
Neuromonitoring leads (tcMEPs and SSEPs) are connected, and the baseline is
obtained before and after positioning and periodically during the case after
decompression and instrumentation.
n
A Foley catheter is placed, and sequential compression devices are placed to
prevent venous thromboembolism.
n
A radiolucent Jackson table is preferred, with the patient in the lateral decubitus
position and prominences padded (a brachial plexus axillary roll is placed two
finger widths below the axilla, along with complete padding of pressure points
(peroneal and ulnar nerves).
148 Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy
P O S I TI O N I N G PE A R L S
• Anesthesia concerns include placement
of a double-lumen tube to facilitate
lung collapse, as needed.
• Neuromonitoring is highly sensitive and
specific to changes in neural function.
• To increase access, some surgeons
prefer the table to be broken during
exposure.
P O S I TI O N I N G PI T FA L L S
• Nonradiolucent table use
• Inadequate neuromonitoring baseline
signals
• Failure to achieve full, true, lateral
decubitus position. Hips and knees
must be perpendicular to the floor.
This affects adequate visualization and
definition of the anterior margin of
the spinal canal, which can make
decompression and instrumentation
more difficult and more dangerous.
• If the table is broken, it is
recommended that it be returned to
the flat position for instrumentation, to
avoid iatrogenic scoliosis with fusion.
n
The lateral decubitus position is necessary, with the choice of the right versus
left side, based primarily on the level of pathology, location of vascular structures
(aorta, azygos venous system), and location of the pathology (i.e., a right-sided
thoracotomy may be chosen for T7-8 right paracentral disk herniation). Defor-
FIGURE 16-4
mity cases are typically approached from the convex side.
P O S I TI O N I N G EQ U I P M EN T
• Double-lumen endotracheal tube
• Radiolucent table
• Fluoroscopy
• Neuromonitoring leads
• Axillary roll, kidney rests, and arm rests
• Headlight
• Thoracotomy instruments and retractors
(long instruments)
• Scalpels (long handles), curettes,
Kerrison and pituitary rongeurs
• High-speed burr/drill
• Screw/rod or screw/plate
instrumentation systems
• Interbody constructs (mesh cages,
modular vertebral column
reconstruction cages, structural
allografts [femoral, humeral, or fibular]
as desired)
• Bone graft
• Drains or chest tubes
• Operating microscope and/or loupes
(optional)
• Right thoracotomy: upper thoracic lesions
• Left thoracotomy: mid- and lower thoracic lesions
n
Three-point secure kidney rests are placed at the posterior sacroiliac spine
(PSIS), “down” scapula, and anteriorly near the xiphoid process. These are quite
helpful measures to ensure that patient orientation is parallel to the floor. The
anterior abdomen hanging free decreases the amount of epidural venous
congestion.
n
The patient is positioned in the lateral decubitus position on a radiolucent table,
perpendicular to the floor after double-lumen endotracheal tube intubation. A
Foley catheter, neuromonitoring leads, axillary roll, kidney rests, and compression
boots are placed. The entire chest wall, from the axilla to below the iliac crest,
across anterior and posterior midlines, is prepared (Figure 16-4).
n
Fluoroscopy AP and lateral views are obtained to establish the level of localiza-
tion of the desired disk space. An incision is marked over the spine and carried
in line with the corresponding rib.
n
Be sure that preoperative intravenous (IV) prophylactic antibiotics are given.
n
Preparation is accomplished with the use of Chloraprep.
n
Draping entails including the contralateral costochondral junction anteriorly, all
the posterior spinal elements, the neck cranially, and the iliac crests caudally.
n
The surgeon typically stands behind the patient, with the first assistant opposite
anteriorly.
P O RTA L S / E X P O S U R ES
P E A R LS
• Level localization
• Always have preoperative imaging
available in the room, and verify the
number of ribs and lumbar segments.
• Match the preoperative sagittal scout
MRI, noting level of pathology, with
the intraoperative fluoroscopy
finding, to identify levels.
• Fluoroscopic AP view allows ribs to
be counted. The incision is marked
laterally centered over the level of
interest as seen in Figure 16-5.
• Intraoperative intrathoracic
visualization: The most cephalad rib
viewed is the second rib.
• Preexisting posterior instrumentation
and known fractures or lesions
identify levels.
• Lumbosacral junction: The surgeon
can count up from this landmark to
the correct level.
• PMMA can be injected via the
vertebroplasty technique in
patients who are morbidly obese
preoperatively.
• If multilevel pathology is to be
addressed, the incision should be
planned two ribs cranial to the desired
level of instrumentation. It is much
easier to expose caudally than cranially.
• For right-sided approaches to the upper
thoracic or cervicothoracic junction, the
third rib is typically excised.
P O RTA L S / E X P O S U R ES
P I T F A L L S
• Upper thoracic exposures are limited by
the scapula.
• The latissimus dorsi can be retracted
but often needs to be divided laterally.
• Excision of the second then first rib can
allow access to the cervicothoracic
junction and cranial extension.
Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy 149
FIGURE 16-5
Portals/Exposures
n
Right- versus left-sided approach: The approach side is based primarily on the
level of pathology, location of vascular structures (aorta, azygos venous system),
and location of the pathology (i.e., a right-sided thoracotomy may be chosen
for eccentric T7-8 right paracentral disk herniation). The thoracic duct also
crosses from right to left around T5.
• Right thoracotomy: upper thoracic lesions; avoids the aortic arch on the left
• Left thoracotomy: mid- and lower thoracic lesions best approached from the
left so that the liver is avoided; aorta is more anterior than lateral at this
point
n
The incision is typically planned with the use of fluoroscopy. After verification
of the number of ribs and/or lumbar segments on preoperative imaging, counting up from the sacrum typically allows reliable identification of mid- to lower
thoracic levels, as does rib identification described above.
n
Figure 16-5 demonstrates a fluoroscopic-guided incision and preoperative-level
identification. The incision is typically planned with the use of lateral fluoroscopy.
Steinman pins are taped to the skin, and fluoroscopic images are taken until
the correct disk space or vertebral level is identified. This is marked, and a 15-cm
incision is marked anteriorly along this rib.
P O RTA L S / E X P O S U R ES
C O N T RO V E R S IE S
• Open versus thoracoscopic approach:
Proponents of thoracoscopy argue
decreased blood loss, postoperative
pain, hospital stay, and morbidity. The
thoracoscopic approach certainly might
be beneficial in nonmorbidly obese
patients with small to moderate mid- to
lower (T4-11) TDHs.
150 Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy
FIGURE 16-6 FIGURE 16-7
S T E P 1 P EA R L S
• Subperiosteal dissection allows
bloodless extrapleural dissection and
avoidance of neurovascular bundle
injury. An intercostal muscle incision
should be made on the superior rib
border if a transpleural approach is
desired to avoid the neurovascular
bundle.
• Bony hemostasis may be achieved
throughout case with bone wax or
hemostatic products, such as thrombinsoaked products—Gelfoam, matrices,
or fibrin sprays.
Procedure
Step 1: Superficial Exposure and
Rib Resection
n
The periosteum is incised superficially with Bovie electrocautery. The incision and
superficial approach is shown in Figure 16-6. A 15-cm incision is planned with
fluoroscopy as previously described. The skin is incised with a scalpel, then Bovie
electrocautery is used to dissect fat down to the selected rib.
n
Figure 16-7 shows rib exposure and resection. Superior, then inferior, periosteal
elevation is performed with a winged-tip elevator, which avoids injury to the
inferior neurovascular bundle. A Doyen rib dissector is used to stay subperiosteal
and extrapleural; then rib cutters are used anteriorly and posteriorly to resect
the rib.
S T E P 1
n
The rib autograft is morselized on the back table.
I N S T RU M E N T A T I O N /
I M P L AN TAT IO N
• Scalpel, electrocautery
• Winged-tip elevators, Doyen rib
dissectors, rib cutters
Step 2: Transthoracic Retropleural Deep Exposure
n
Figure 16-8 shows transthoracic retropleural exposure. Metzenbaum scissors are
used to incise the deep rib bed periosteal layer, but they stay extrapleural.
Retropleural dissection is performed by a combination of finger, sponge, and
S T E P 1 C ON T R O V ER S I E S
• Rib resection versus spreading:
Resection affords better visualization
but possibly increases intercostal
neuralgia and wound closure problems.
Kittner dissection, which allows elevation and separation of parietal pleura from
the periosteal layer.
n
Figure 16-9 shows deep spine exposure and level identification. After ipsilat-
eral lung deflation, moist lap pads and self-retaining rib retractors gently retract
pleura, lung, and aorta, to gently expose “peaks” (disks) and “valleys” (bodies)
of the spine. A spinal needle is put into the disk space; then fluoroscopy is
used to identify the correct level. A segmental artery is noted at the adjacent
S T E P 2 P EA R L S
• Retropleural exposure allows avoidance
of chest tube and caudal retroperitoneal
extension, thus avoiding a diaphragm
incision and takedown.
• Rib head resection: Exposure is
performed with Cobb elevators,
curettes, and electrocautery releases
costotransverse and costovertebral
ligaments and joints. Rib head removal
exposes caudal pedicle, adjacent
neuroforamina, and posterior vertebral
margin (anteriormost aspect of spinal
canal), although the sympathetic chain
is sometimes disrupted.
vertebral body waists (
n
Figure 16-10 shows segmental artery ligation. Segmental arteries are located
stars
at the vertebral body waist and ligated (two silk ties are used about 1 cm away
from aorta to prevent vessel avulsion off the aortic wall).
).
S T E P 2 P IT FA L L S
• Wrong-level surgery: One must know
the number of lumbar segments
preoperatively and be able to count
up from the lumbosacral junction
intraoperatively, to correlate with
preoperative images.
• Level identification by rib counting can
be done by knowing the number of
ribs preoperatively and counting
cranially from the twelfth rib (T11-12
interspace) or the second rib (which is
typically the most cranial rib visualized).
• Correlate the preoperative sagittal scout
MRI, noting the level of pathology, with
the intraoperative fluoroscopy finding,
to identify levels.
• Segmental vessel injury: Care must be
taken to ligate the artery at least 1 cm
from the aorta to avoid avulsion from
the aortic wall.
S T E P 2
I N S T RU M E N T A T I O N /
I M P L AN TAT IO N
• Self-retaining rib retractors with moist
sponges (retract lung, pleura, and aorta
gently)
• Spinal needle
• Fluoroscopy
Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy 151
FIGURE 16-8
S T E P 2 C ON T R O V ER S I E S
• Iatrogenic spinal cord ischemia resulting
from preoperative embolization or
intraoperative segmental artery ligation:
Some advocate temporary occlusion of
segmental vessels by clipping or
suturing, then running a tcMEP/SSEP to
ensure no changes before definitive
ligation. Murakami and colleagues have
demonstrated evidence of iatrogenic
spinal cord demise in canines and
humans undergoing three-level bilateral
segmental artery interruption for tumor
cases.
FIGURE 16-9
FIGURE 16-10
152 Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy
FIGURE 16-11
S T E P 3 P EA R L S
• The anterior longitudinal ligament,
anteriormost disk, adjacent end plates,
and vertebral bodies need not be
removed for this procedure.
• Cavitation: The empty disk space is
utilized as a “cavity” to allow
deposition of bone and disk as needed,
thus allowing maneuvers to be directed
away from the spinal canal at all times.
• Corpectomy cases: Complete
diskectomy can be performed above
and below the corpectomy level with a
combination of rongeurs, curettes, and
a high-speed burr.
S T E P 3 P IT FA L L S
• Durotomy and/or neurologic injury
is most likely to occur if the surgeon
attempts excision of posterior calcified
disk material and OPLL before
establishing adjacent spinal cord
decompression via hemicorpectomies.
S T E P 3 C ON T R O V ER S I E S
• There are questions about using an
isolated diskectomy versus additional
interbody arthrodesis, with or without
instrumentation if pure soft disk
herniation is present. Guidance in the
literature is sparse, although many
advocate for additional arthrodesis
and instrumentation to either treat or
prevent thoracic axial pain or deformity.
FIGURE 16-12
Step 3: Diskectomy
n
A partial diskectomy is performed using a combination of curettes and pituitary
rongeurs. Figure 16-11 shows a diskectomy. A 15-blade scalpel on long handle
is used to create an annulotomy in a rectangular configuration anteriorly and
posteriorly and at adjacent disk–end plate junctions. A Cobb elevator is used to
elevate and release the disk off the end plates.
n
Direct decompression of calcified posterior disks in the spinal canal or OPLL is
deferred until an adjacent hemicorpectomy is performed.
Step 4: Hemicorpectomy and Spinal Cord Decompression
n
Figure 16-12 shows caudal T12 hemicorpectomy. Cranial and caudal partial
hemicorpectomies are performed to safely decompress the cord above and
below maximal compression at the posterior calcified disk and osteophytes.
Planned decompression is aided by preoperative planning, although excision
must not be excessive, or else lateral screw/plate construct fixation can be
compromised (see Figure 16-2). Osteotomes are used to create the initial craniocaudal extent of bony resection.
n
Curettes are used to sequentially remove bone into the disk space, away from
the canal.
n
Excision of calcified disk and osteophytes, and complete spinal cord decompres-
sion, is performed last under direct vision, with all maneuvers directed away
from the spinal cord, or, alternatively, with a high-speed diamond-tipped burr.
Figure 16-13 shows decompression. The entire spinal canal is decompressed
from pedicle to pedicle, and a caliper is used to measure the interbody device
height.
S T E P 4 P EA R L S
• The open transthoracic approach
is unique in allowing safe cord
decompression under direct vision for
central, large, calcified disk herniations.
• An adjacent partial hemicorpectomy
allows for better definition of the
“normal” spinal canal and cord before
moving to the most stenotic calcified
disk–osteophyte complex.
• Complete anterior partial
hemicorpectomy is not needed for the
case illustrated, although multilevel
sequential or en-bloc complete
corpectomy can be accomplished in
tumor cases.
• Direct repair of inadvertent durotomy is
best accomplished by an open anterior
approach.
S T E P 4 P IT FA L L S
• Excessive hemicorpectomy resection
can compromise plate/screw stability.
Complete corpectomy with extension of
instrumentation may be required.
• Nonparallel hemicorpectomy resections
can compromise subsequent interbody
arthrodesis and cage placement, and
they can induce iatrogenic sagittal or
coronal deformity.
S T E P 4
I N S T RU M E N T A T I O N /
I M P L AN TAT IO N
• Osteotomes
• High-speed burr
S T E P 5 P EA R L S
• The neuroforamen and posterior
vertebral margin (above and below),
define the spinal canal and allow
accurate anteroposterior placement
without fluoroscopy.
• Careful notation of vertebral body
width on preoperative imaging allows
accurate cage insertion to the correct
depth. For example, Figure 16-2 shows
a vertebral body width of 40 mm with
a 20-mm cage selected, allowing
10 mm laterally on each side.
Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy 153
FIGURE 16-13
Step 5: Arthrodesis, Cage Preparation, and Insertion
n
Cage sizing:
while the cage diameter can typically be selected based on preoperative imaging.
n
Cage options:
tion), PMMA, or structural allograft may be used.
• Mesh cages can be used in any interbody defect (diskectomy, partial or complete corpectomies).
• Modular cage: Variability in body and end plate sizes, and sagittal plane
lordosis or kyphosis, can be attained, although sturdy preserved end plates
are needed for placement.
n
Cage cutting and graft (local autograft) preparation
• Graft options: local autograft
◆
Autograft (local): morselized versus strut, prepared on back table
◆
Allograft: structural versus corticocancellous freeze-dried croutons
◆
Biologic adjuvants
◆
Local bone marrow aspiration
• The mesh cage can be cut on the back table with the aid of the manufacturer’s
tools. Figure 16-14 shows cage selection, cutting, and insertion. A handheld
cage cutter (A) is used to create the cage height. Local autograft is inserted
into the cage and loaded onto the handle for insertion, and then it is malleted
into place (B).
n
When the cage is at the appropriate depth, the inserter is removed.
A caliper determines interbody cage or structural allograft height,
Titanium mesh cages, modular cages (vertebral body reconstruc-
154 Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy
S T E P 5 P IT FA L L S
• Cage malposition: in spinal canal,
eccentric location, inducing local
sagittal or coronal deformity
• Cage subsidence
• Structural allograft resorption (when
used)
S T E P 5
I N S T RU M E N T A T I O N /
I M P L AN TAT IO N
• Calipers
• Cage cutters
• Rongeurs: used to prepare local
autograft
• Mallet
A
S T E P 6 P EA R L S
• Bicortical screw placement is ideal,
and one may gently reach around the
contralateral side of the vertebral body
to palpate for the bicortical position.
• Dual screw/rod constructs aid in
stability.
• Anterior column cages and grafts are
best placed with screw/plate or screw/
rod constructs, to prevent migration,
subsidence, and increased arthrodesis
rates.
• Residual anterior cortical bone can also
decrease dislodgement.
• An alternative technique would involve
placement of vertebral body screws,
then use of distraction instrumentation,
followed by cage insertion and
compression of the cage when
distraction forces are removed.
Step 6: Screw/Plate Instrumentation
n
Many plate/screw options are possible. Single or dual screws, in addition to
compression or locking plates, are available.
n
Figure 16-15 shows anterolateral screw and plate instrumentation. Posterior
vertebral screws are typically placed directly parallel to the cord, side to side in
vertebral bodies (see Figure 16-15, A). A pilot entry starting hole is created
B
FIGURE 16-14, A-B
with either a high-speed burr or starter awl; then preplanned appropriate-
S T E P 6 P IT FA L L S
• Screw malplacement
• Neurologic, vascular, or visceral injury
• Incidental durotomy
• Pseudarthrosis
length screws are placed. Anterolateral plate placement and compression of
the underlying cage and adjacent vertebral bodies are shown in Figure 16-15,
B
. Anterior screws are typically angled slightly posterior, to converge and triangulate with posterior screws (see Figure 16-15, C ). Locking screw caps are
placed to finally tighten the construct.
n
Fluoroscopy: AP (Figure 16-16, A) and lateral (Figure 16-16, B) fluoroscopy is
used to check final implant position.
S T E P 6
I N S T RU M E N T A T I O N /
I M P L AN TAT IO N
• Anterolateral screw/plate or screw/rod
implants
• High-speed burr or awl
• Compression and distraction
instrumentation
• Fluoroscopy
Step 7: Closure
n
Thorough irrigation of the spinal bed, retropleural space (or thoracic cavity), and
inspection of mediastinal structures with meticulous hemostasis is performed;
then thoracic instruments and retractors are removed.
n
Closed-suction Jackson-Pratt or Hemovac drain placement (retropleural) is done
under direct vision, one to two interspaces caudal to incision.
n
Inadvertent parietal pleural repair is done (if small rent noted).
n
Closure is then performed in layers in the following order: (1) rib bed periosteal
closure, (2) innermost, (3) intercostal, (4) internal intercostal, (5) external intercostal, (6) subdermal, and (7) subcuticular.
n
The dressing is applied.
Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy 155
B
A
FIGURE 16-15, A-C
A
C
FIGURE 16-16, A-B
B
156 Procedure 16 | Anterior Thoracic Diskectomy and Corpectomy
C O M P LI C AT IO N S
• Pulmonary complications: Pleural
effusion, pneumothorax, and
hemothorax can be managed with
thoracocentesis or chest tube
placement. Atelectasis can require chest
physiotherapy and incentive spirometry,
and can be decreased by intermittent
lung inflation intraoperatively every half
hour. Deep empyema is rare.
• Approach-related complications include
intercostal neuralgia, surgical site
infection, and wound dehiscence.
• Vascular injury: Damage to the aorta,
vena cava, azygos venous system, or
segmental neurovascular bundle is
possible. Prompt repair by a thoracic
surgeon is required.
• Chylothorax rarely occurs with injury to
the thoracic duct.
• Neurologic injury: Intraoperative
changes in neuromonitoring (SSEPs
or tcMEPs) mandate an immediate
evaluation of preceding anesthetic and
surgical steps, including evaluation of
blood pressure, anesthetic agents,
recently placed instrumentation, grafts,
and decompression or reduction
maneuvers. Postoperative neurologic
deficit mandates STAT evaluation of
instrumentation, interbody grafts, and
evaluation of the operated neuraxis,
because malpositioned hardware,
dislodged grafts, and epidural
hematomas can cause neurologic
demise. STAT radiographs and CT scans
can be obtained rapidly, and MRI can
be obtained to evaluate neurologic and
soft tissues after evaluation of bony
anatomy and hardware.
• Horner syndrome can be encountered
by disruption of the sympathetic chain.
• Primary duratomy repair can be
augmented with synthetic agents as
needed, including fibrin glue and
synthetic dural patches or grafts. A
lumbar drain can also be placed. If a
chest tube is used, it should be placed
to prevent a cerebrospinal fistula.
• Inadequate decompression can be a
cause of failure to relieve preoperative
neurologic symptoms and should be
evaluated with appropriate crosssectional imaging.
• Fusion-related complications:
Pseudarthroses, graft dislodgement,
subsidence, and adjacent vertebral
fractures are possible, although rare,
complications of interbody arthrodesis.
Hardware malposition (particularly
screw/plate constructs) is seen more
commonly.
Postoperative Care
n
The patient is extubated, and monitoring overnight is usually done in the inten-
sive care unit (ICU).
n
Pain consultation and/or patient-controlled analgesia (PCA) are standard.
n
Perioperative antibiotics are maintained for 24 hours.
n
The drain is removed once less than 30 mL per shift accumulates.
n
A postoperative chest radiograph is not routinely ordered.
n
Postoperative thromboembolic prophylaxis is typically mechanical.
n
Early ambulation is necessary.
n
No bracing is usually done postoperatively.
n
To verify the construct under physiologic loading, standing anteroposterior and
lateral radiographs are obtained before discharging the patient from the
hospital.
Expected Outcomes
n
Although indications are broad for anterior thoracic diskectomy or corpectomy,
including degenerative, traumatic, neoplastic, infectious, and deformity-based
etiologies, thoracic disk herniation remains relatively more common than the
other indications.
n
The natural history of symptomatic thoracic disk herniation is progressive, with
most patients undergoing operation for neurologic progression with myelopathy
or perseverating pain. Neurologic pathogenesis probably results from a combination of mechanical compression and vascular ischemia.
n
Surgical approaches are numerous, including anterior, posterior (laminectomy,
transpedicular, transfacet, costotransversectomy, lateral extracavitary), thoracoscopic, and endoscopic. Each approach has inherent advantages and
disadvantages.
n
Paramount to choosing the appropriate approach is knowing the location (level,
sidedness), extent, nature (“hard” versus “soft” disk), medical comorbidities,
body habitus, and symptomatology.
n
The literature is sparse (mostly level 3 to 5 retrospective studies) for directly
comparing individual approaches, partly because thoracic disk herniations are
relatively rare. Most patients experience nearly a one-grade improvement in the
Frankel grading scale for motor strength and decreased radicular and/or axial
pain.
n
Laminectomy has been essentially abandoned because of the possibility of
neurologic deterioration.
n
Anterolateral open thoracotomy still remains the gold standard by which all
other approaches are compared. Excellent direct visualization of neural elements
and multilevel access are clear advantages, although morbidity and the need
for access surgeons are the major disadvantages. Nearly all patients have good
neurologic outcomes.
n
Thoracoscopic approaches may offer reduced pain, shorter hospital stays, less
blood loss and fewer transfusions, and less risk of intercostal neuralgia.
n
Upper thoracic disks may be best managed by costotransversectomy, given a
more difficult transthoracic access.
n
Good results can be accomplished through a variety of surgical approaches, as
long as major principles of spine surgery are maintained: adequate operative
exposure, necessary decompression of neural elements, appropriate spinal
reconstruction in the face of instability, and meticulously layered wound
closures.