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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_583_Библиотеки_им_академика_М_И_Перельмана
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Rod-Screw Stabilization ofthePosterior
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Cervical Spine
UweVieweg
40
40.1 Introduction and Core Messages
Posterior rod-screw systems have a history of successful clinical use. The posterior rod-screw technique,
with the screw positioned in the lateral mass or transpedicularly, provides a stable tension band system. For
xation to the occiput, an occiput plate has been
designed. The complete system includes top-loading
screws, rods, offset connectors, cross connectors,
clamps, laminar hooks, and occiput screws and plates.
40.2 Indications
• Upper and lower cervical spine instabilities (rheumatoid
arthritis, anomalies, traumatic instabilities, infections,
tumours, deformities).
• Anterior fusions requiring additional posterior
stabilization.
• Instability associated with deciency of the posterior elements from laminectomy or fractures.
40.3 Contraindications
40.4 Technical Prerequisites
Fluoroscopy, positioning device (e.g. padded rolls), rigid
head holder (e.g. Mayeld), and adequate implants (polyaxial rod-screw systems) and instruments are essential for the
procedure.
40.5 Planning, Preparation,
andPositioning
A CT for preoperative planning is recommended (anatomical
variation, conrm pedicle orientation, planning of implant
size, etc.). The patient is placed on the operating table in the
prone position and secured with the desired sagittal alignment. Accurate positioning is especially important when xing the occiput to the cervical and thoracic spine. Conrm
proper alignment using an image intensier or radiograph
prior to draping. The neck and shoulder are prepped and
draped in the usual manner. The sitting position is an
alternative.
40.6 Surgical Technique
• Signicant damage to the vertebral bodies.
U. Vieweg (*)
Department of Conservative and Surgical Spine Therapy with
Interdisciplinary Spinal Deformities Centre and Rummelsberg
Sectional Center, Hospital Rummelsberg,
Schwarzenbruck, Germany
e-mail: uwe.vieweg@sana.de
© Springer-Verlag GmbH Germany 2023
U. Vieweg, F. Grochulla (eds.), Manual of Spine Surgery, https://doi.org/10.1007/978-3-662-64062-3_40
40.6.1 Approach
• A posterior midline incision is performed.
• The incision is taken down through the subcutaneous tis-
sue and facia with electrocautery.
• If fusion is to include the occiput, exposure should be
extended to the external occipital protuberance.
• All soft tissue is removed from the posterior bone struc-
tures, and the lateral mass is identied. The medial border
of the lateral mass is the valley at the junction of the lamina and lateral mass. The lateral boundary is the far edge
of the lateral mass. The superior and inferior borders are
the respective cranial and caudal facet joints.
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U. Vieweg
a
b
Fig. 40.1 Pedicle screw (a) and lateral mass screw (b) (With permis-
sion of Aesculap AG, Tuttlingen, Germany)
40.6.2 Instrumentation [1–3]
Rod-Screw Stabilization without Occiput
• In general, the screws can be placed in two different
ways—either (a) transpedicular, with pedicle screws
inserted from lateral to medial through the pedicle or (b)
lateral mass, with lateral mass screws inserted from
medial to upper lateral (see Fig.40.1a, b). Though there
are dangers associated with the insertion of cervical pedicle screws, their use is advantageous in some clinical conditions when increased load bearing is necessary [4].
Fig. 40.2 Screw entry points for lateral mass screw (red) and for ped-
icle screws (blue). The entry point for the screws is 2mm medially and
cranially to the centre of the lateral mass (With permission of Aesculap
AG, Tuttlingen, Germany)
• Depending on the anatomy, different entry points for the
screws may have to be chosen. The entry point for the
lateral mass screws is more medial than the entry point for
the pedicle screws. The entry point for the lateral mass
screw lies 2mm medially and cranially to the centre of the
lateral mass (see Fig.40.2).
• The lateral mass screws are placed as described by Magerl
[5] (see Fig.40.3). Note: in order to achieve the correct
drilling direction, partial resection of the spinous process,
which is in the way, may be helpful.
• The screw trajectory is about 20–25° outwards (lateral to
the spinous process) and 30–40° cranially. The cranial
angulation attempts to parallel the facet joint. Note: the
inclination of the surface can be determined by inserting a
ne dissector into the joint.
40 Rod-Screw Stabilization ofthePosterior Cervical Spine
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279
Fig. 40.3 Positioning of the lateral mass screws as described by Magerl.
The screw orientation is about 20–25° outwards (lateral to the spinous
process) and 30–40° cranially. The cranial angulation attempts to parallel
the facet joint (With permission of Aesculap AG, Tuttlingen, Germany)
• An awl may be used to open the cortex. Alternatively, a
1–2mm drill hole can be made using a small decortication burr.
• The lateral mass is drilled with an adjustable drill guide
using uoroscopic imaging. Note: the drill guide is initially set at 12mm. The depth of the hole is checked
with a depth sounder (see Figs. 40.4 and 40.5). The
Fig. 40.4 Drilling of the lateral mass using uoroscopic imaging
(With permission of Aesculap AG, Tuttlingen, Germany)
length of the adjustable drill guide is increased in 1 to
2 mm increments until the drill penetrates the far
cortex.
• With the pedicles or lateral mass prepared and the
proper screw length determined, the appropriate screws
are inserted into the predrilled holes bilaterally, using
the self-holding polyaxial screwdriver (see Figs. 40.6
and 40.7).
• Once the screw is inserted, the position of the polyaxial
head is optimized for rod insertion using a screw body
manipulator.
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U. Vieweg
Fig. 40.5 The hole is checked for penetration with a depth gauge
(With permission of Aesculap AG, Tuttlingen, Germany)
Fig. 40.7 Complete
rod-screw construct C3-Th2
(With permission of Aesculap
AG, Tuttlingen, Germany)
Fig. 40.6 Screw insertion with self-holding screwdriver (With permis-
sion of Aesculap AG, Tuttlingen, Germany)
40 Rod-Screw Stabilization ofthePosterior Cervical Spine
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Fig. 40.8 Positioning of the occipital plate (With permission of
Aesculap AG, Tuttlingen, Germany)
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• After the insertion of the screws, and prior to insertion of
the rods, the lordotic alignment of the cervical spine
should be veried via intraoperative lateral uoroscopy. A
trial rod template can be used to aid in rod contouring or
trimming to the required length.
• Insertion of the set screw in the polyaxial body is started
by turning the instrument counterclockwise until a click is
heard or felt. The set screws are hand tightened with the
set screw starter and then nally tightened to the predened optimum torque with a torque-limiting screwdriver and the countertorque handle.
• Cancellous bone graft is applied over the decorticated
laminae and articular masses.
Rod-Screw Stabilization withOcciput
• The occiput plate should be placed medial to the external
occipital protuberance and the foramen magnum. The
greatest stability of the plate is achieved by midline xation at the inion where the bone thickness is highest (see
Fig.40.8).
• A drill guide can be used to hold the plate onto the
occiput. Note: even if the drill depth was measured before
Fig. 40.9 Drilling of the occipital bone (With permission of Aesculap
AG, Tuttlingen, Germany)
surgery, proceed with care to prevent damage to the dura
(see Fig.40.9).
• By using the tap guide and the tap, the drilled hole is further prepared for insertion of the occipital screws.
• The occipital screws are inserted, and the plate is xed on
the occipital bone. The occipital screws can be inserted in
the appropriate holes using a screwdriver (see Fig.40.10).
• To connect the occipital plate to the cervical spine, a prebent rod is inserted into the rod receptacles and xed with
set screws.
• Finally, the set screws have to be locked using a torque
wrench and countertorque handle (see Fig.40.11).
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Fig. 40.10 Screw insertion in the occipital bone (With permission of
Aesculap AG, Tuttlingen, Germany)
U. Vieweg
References
1. Aebi M, Thalgott JS, Webb JK.Chapter 6: posterior techniques
lower cervical spine. In: AO ASIF principles in spine surgery.
Berlin/Heidelberg: Springer; 1998. p.54–76.
2. Dickman CA, Sonntag VKH, Marcotte P.Techniques of screw xation for the upper cervical spine. BNI Q. 1992;8:9–26.
3. Dickman CA, Douglas R, Sonntag VKH.Occipitocervical fusion:
posterior stabilization of the craniovertebral junction and upper cervical spine. BNI Q. 1990;6:2–14.
4. Dunlap BJ, Karaikovic EE, Park HS, etal. Load sharing properties
of cervical pedicle screw-rod constructs versus lateral mass screwrod constructs. Eur Spine J. 2010;19(5):803–8. Epub 2010 Feb 2
5. Magerl F, Grob D.Dorsal fusion of the cervical spine with the hook
plate. In: Kehr P, Weidner A, editors. Cervical spine. 2nd ed. Berlin:
Springer; 1987.
Fig. 40.11 Complete construct (With permission of Aesculap AG,
Tuttlingen, Germany)
Part V
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Anterior Thoracic Spine
Overview ofSurgical Techniques
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andImplants
ChristianSchultz
41.1 Introduction and Core Message
The chapter gives an overview to the different
approaches (extended anterior cervical approach,
periscapular approach and cervical thoracic approach
with osteotomy of the manubrium to the upper thoracic
spine; posterolateral transthoracic approaches to the
mid-level and lower thoracic spine), different approach
techniques (open/mini-open approach, microendoscopic approach) and different implants (plate-screw
systems, rod-screw systems, vertebral body replacements) for the anterior thoracic spine.
41
41.2 Approaches
41.2.1 Open/Mini-Open Anterior Approach
totheCervicothoracic Junction (T1–T2)
• Caudally extension of the standard anterior lower cervical
approach to dissect between the trachea and the esophagus medially and the innominate vessels inferolaterally.
• Exposure of the anterior wall of the vertebral bodies and
the intervening discs (see Fig.41.1).
• Identication of internal jugular vein, common carotid
artery, the recurrent laryngeal nerve and the thoracic duct.
With this approach, it is usually possible to attain the vertebral bodies T1 and T2; in some individual cases, one can
reach the T3/T4 level. For more caudal access, there is a need
for median sternal bone resection [1].
C. Schultz (*)
Augsburg, Germany
e-mail: schultz.christian@gmx.de
Fig. 41.1 Anterior approach to the cervicothoracic junction
41.2.2 Open/Mini-Open Anterior Approach
totheUpper Thoracic Spine (Level T3–T4)
• Common cervicosternal approach with an osteotomy of
the clavicle and an individual-sized sternotomy depending on the extent of the pathology.
• In case of sternotomy, the brachiocephalic vein has to be
ligated.
Because of the ligation and section of the left brachiocephalic vein, the risk of injury of the thoracic duct increases.
The superior intercostal vessels should be preserved.
Alternative to decrease the morbidity:
• Exposure of the level T1 to T4 between the right brachio-
cephalic vein and the brachiocephalic artery.
The level T4–T5 can be exposed between the superior
vena cava and the ascending aorta using a transmanubrium
approach without ligation and section of the left brachiocephalic vein.
© Springer-Verlag GmbH Germany 2023
U. Vieweg, F. Grochulla (eds.), Manual of Spine Surgery, https://doi.org/10.1007/978-3-662-64062-3_41
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41.2.3 Lateral Approach totheUpper
Thoracic Spine
• Skin incision at the inferior scapula.
• Dissection of the latissimus dorsi and the serratus muscle
to fold away the scapula.
• Intercostal opening or resection of the ribs depending on
the extend of pathology.
This approach can lead to signicant morbidity because
of the extensile muscle dissection [2].
41.2.4 Open/Mini-Open Approaches
totheMid-Level Anterior Thoracic
Spine (Level T5–T9)
Standard anterior approach until the level T9 is by a right
posterolateral thoracotomy:
• Positioning on the left side (vacuum bed), abduction of
the right arm 120°.
• Skin incision depending on the level and extend of
pathology.
• Dissection of the latissimus dorsi muscle if necessary and
as distal as possible.
• Dissection of the serratus muscle also as distal as possible
to avoid lesions of the long thoracic nerve and the lateral
thoracic artery.
• Intercostal approach to the spine, in rare cases rib
resection.
On the T4 level, the azygos arch ends in the superior vena
cava. The azygos arch crosses the vagus nerve running on the
surface of the esophagus. The anterior intercostal veins from
the higher vertebral bodies end in the vertex of the azygos
arch crossing the vertebral bodies perpendicularly (Fig.41.2).
The sympathetic trunk and ganglia continue to be nearby the
rib heads [3].
C. Schultz
Fig. 41.2 View at the azygos vein at the level T5
41.2.5 Open/Mini-Open Approaches
totheLower Anterior Thoracic Spine
(Level T10–T12)
Standard anterior approach to the lower levels is the left lateral thoracotomy:
• Skin incision on the tenth rib.
• Dissection of the latissimus dorsi muscle and intercostal
thoracotomy (Fig.41.3).
This approach leads into the costodiaphragmatic recess,
and with an additional diaphragm split, it is possible to reach
the level L2 [4].
Fig. 41.3 Open approach to the lower anterior thoracic spine with the
SynFrame Retractor System (DePuySynthes)
41 Overview ofSurgical Techniques andImplants
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Fig. 41.4 Trocar positioning
for the endoscopic approach
to the level T6 from the right
side
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41.2.6 Endoscopic Approaches Upper Anterior
Thoracic Spine (Level T2–T4)
Demanding nearly transaxillary approach for experienced
surgeons:
• Positioning on the left side, arm lifted upwards.
• Four portals with the working portal above the pathology,
the camera portal caudal in the same line, suction and irri-
gation portal anterocranial, and the retractor portal
caudal.
The thoracodorsal and axillary vessels, the long thoracic
nerve and the brachial plexus could be compromised. For
these thoracic levels, the open approach still is the standard
approach [5].
41.2.7 Endoscopic Approaches Mid-Level
Anterior Thoracic Spine (Level T5–T8)
Because of the position of the great vessels and the heart
approach from the right side:
• Lateral position on the left side.
• Portal position as stated above (Fig.41.4).
The side of approach depends on the position of
the aorta; therefore, a preoperatively CT or MRI is
desirable.
41.2.8 Endoscopic Approaches Lower Level
Anterior Thoracic Spine (Level T9–T12)
Because of the liver, the lower levels have to be approached
from the left side:
• The working portal is also located above the pathology,
the camera portal is located two intercostal spaces cranial
to the working portal and suction and retractor portal are
each located anterior.
41.3 Implants
41.3.1 Rod-Screw andPlate-Screw Systems
These implants for stabilisation of the anterior spine are usually used combined with bone graft or additional implants
like vertebral body replacements (VBR). The new implants
provide an angle-stable constrained construct with four-point
stability like the TRUSS Thoracolumbar Plate (Globus
Medical) or the MACS TL System (with permission of
Aesculap, Tuttlingen, Germany) (Fig.41.5) with:
• Low prole, smoothed edges and a safe screw insertion
due to the monocortical screw design.
• A design for open and endoscopic procedures with.
• Cannulated instruments and implants to simplify the endo-
scopic application with k-wire-guided instrumentation.
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