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Implant and instrument system for anterior lumbar interbody fusion
SynCage-LRSurgical Technique
Image intensifier control
This description alone does not provide sufficient background for direct use of DePuy Synthes products. Instruction by a surgeon experienced in handling these products is highly recommended.
Processing, Reprocessing, Care and MaintenanceFor general guidelines, function control and dismantling of multi-part instruments, as well as processing guidelines for implants, please contact your local sales representative or refer to:http://emea.depuysynthes.com/hcp/reprocessing-care-maintenanceFor general information about reprocessing, care and maintenance of Synthes reusable devices, instrument trays and cases, as well as processing of Synthes non-sterile implants, please consult the Important Information leaflet (SE_023827) or refer to: http://emea.depuysynthes.com/hcp/reprocessing-care-maintenance
SynCage-LR Surgical Technique DePuy Synthes 1
Table of Contents
Introduction Overview 2
AO Principles 3
Indications and Contraindications 4
Surgical Technique Preoperative Planning 5
Access and Exposure 6
Preparation and Trial Implantation 7
Selection and Packing of Implant 11
Implant Insertion 13
Product Information Implants 17
Additional Instruments 21
Filling Material 23
Additional Recommended Sets 27
Bibliography 30
2 DePuy Synthes SynCage-LR Surgical Technique
Overview
SynCage-LR (PEEK cage)
The SynCage-LR implant and instru-ment system is designed for anterior lumbar interbody fusion (ALIF).
Superior biocompatibilitySynCage-LR is consist of pure medical grade PEEK (Polyetherether-ketone). It contains no carbon fibre, thereby reducing the risk of systemic uptake and local connective tissue formation.
Enhanced fitAn expanded range of implants in-cluding 3 profiles, 5 heights and 2 footprints to ensure desired fit in all patients.
Specialised L5–S1 implantA specific implant designed to fit the L5–S1 level.
Made of clinically proven PEEK Optima
Radiolucent• PEEK facilitates radiographic assess-
ment of fusion
coronalaxial
sagittal
SynCage-LR Surgical Technique DePuy Synthes 1
Copyright © 2012 by AOSpine
The four principles to be considered as the foundation for proper spine patient management underpin the design and delivery of the Curriculum: Stability – Alignment – Biology – Function.1, 2
FunctionPreservations and restora-tion of function to prevent disability
StabilityStabilization to achieve a specifi c therapeutic outcome
AlignmentBalancing the spine in three dimensions
BiologyEtiology, pathogenesis, neural protection, and tissue healing
AO Spine Principles
1 Aebi et al (1998)2 Aebi et al (2007)
4 DePuy Synthes SynCage-LR Surgical Technique
IndicationsLumbar and lumbosacral pathologies which may require anterior segmental arthrodesis, including:• Degenerative disc disease and instability• Revision surgery for failed decompression
syndrome or pseudoarthrosis• Reduced spondylolisthesis
Contraindications• Spinal fractures• Spinal tumor• Osteoporosis• Infection
Indications and Contraindications
SynCage-LR Surgical Technique DePuy Synthes 5
Preoperative Planning
1. Preoperative planning
Instruments
X000074 X-ray Templates for SynCage-LR and SynCage PROmotive, 24 × 30 mm, 12°
X000075 X-ray Templates for SynCage-LR and SynCage PROmotive, 28 × 38 mm, 10°
X000076 X-ray Templates for SynCage-LR and SynCage PROmotive, 28 × 38 mm, 12°
Determine the approximate implant size by comparing the SynCage-LR Radiographic Template (Fig. 1) with a lateral radiograph of the patient’s adjacent intervertebral discs.
Notes:• The height indicated on the template is approxi-
mately 1 mm lower than that of the actual spacer to account for penetration of the teeth into the ver-tebral endplate.
• It is recommended to select the maximum implant size, to increase the stability of the segment through tension in the longitudinal ligaments.
(Fig. 1)
6 DePuy Synthes SynCage-LR Surgical Technique
Access and Exposure
1. Patient positioning
For an anterior approach to the lower lumbar levels, the patient is placed in a slight Trendelenburg position.
3. Exposure
For anterior insertion, expose the intervertebral disc such that there is sufficient space on either side of the verte-bral midline, equal to half the width of the implant. If the vessels and /or tissues cannot be retracted suffi-ciently, insertion from an anterolateral direction may be indicated.
2. Anterior access and approach
Recommended set
01.609.102 Set SynFrame RL, lumbar
187.310 SynFrame Basic System in Vario Case
The surgical approach depends on the level to be treated. Locate the correct operative disc level and in-cision location by taking a lateral flouroscopic view while holding a straight metal instrument at the side of the patient. This ensures that the incision and exposure will allow direct visualization into the disc space.
Expose the operative disc level through a standard retro-peritoneal approach.
Note: If a retraction system such as the SynFrame is used, pay attention to the positioning of soft tissue or Hohmann retractors as they may interfere with the screw insertion.
SynCage-LR Surgical Technique DePuy Synthes 7
Preparation and Trial Implantation
1. Cut anterior window
Cut a rectangular window the width of the SynCage-LR into the anterior longitudinal ligament and annulus fibro-sus.
A trial implant (see page 17) may be used as a template to indicate the width of the window.
Retain as much of the anterolateral, lateral and posterior annulus as possible in order to provide the necessary stability of the instrumented segment.
2. Prepare disc space
Recommended set
01.600.100 Proprep Set
Excise the disc material and remove the cartilaginous endplates to expose the underlying bony vertebral end-plates.
Adequate clearance of the endplates is important to en-able the provision of a vascular supply to the bone graft. Excessive clearance or use of a rasp however, may weaken the endplate and result in subsidence of the cage.
8 DePuy Synthes SynCage-LR Surgical Technique
3. Distract segment
Instruments
397.113 Distractor, anterior, for SynCage-LR
397.126 Distractor, lumbo-sacral, for SynCage-LSR
For a placement, verify spreader position with the help of an intraoperative lateral x-ray.
Distraction of the segment is essential for restoration of disc height, opening of the neural foramina and initial stability of the SynCage-LR. To ensure that the SynCage-LR is inserted symmetrically into the disc space, the line on the blades in dicating the vertebral midline is aligned with the anterior midline of the vertebral bodies. Com-pressing the Distractor Handle opens the disc space.
Note: Due to the wedge shaped configuration of the disc and the distractor blades, the distractor must be held in place during distraction and the insertion of the trial or implant to prevent its displacement and possible injury to adjacent structures.
Once the endplates have been prepared, complete even-tual additional surgical procedures (i.e. removal of a disc fragment from the spinal canal).
Note: It is essential that the nucleus and the inner annulus are removed to prevent displacement of disc material into the spinal canal during spacer insertion and interference with bone in-growth.
Preparation and Trial Implantation
SynCage-LR Surgical Technique DePuy Synthes 9
4. Determine trial implant size
Instruments
357.160 – SynCage-LR Trial Implant, 12.0–19.0 mm357.164
397.121 SynCage-LR Trial Implant, broad, 12.0 mm, Pure Titanium
397.101– SynCage-LR Trial Implant, broad,397.104 13.5–19.0 mm
357.150– SynCage-LSR Trial Implant, 357.154 12.0–19.0 mm
397.034 Handle for SynCage Trial Implants, straight
397.035 Handle for SynCage Trial Implants, angled
Select the trial implant that corresponds with the SynCage-LR size determined during the pre operative planning. Attach it to the handle for trial implants. The handle must be tightened firmly to prevent loosening of the trial implant.
The distractor is designed to be used to assist with guid-ing the trial implant into the disc space. To ensure that the implant is inserted symmetrically into the disc space, the central line on the distractor blades should be aligned with the anterior midline of the vertebral bodies.
Slide the trial implant between the distractor blades into the disc space. Controlled and light hammering on the handle for trial implants may be required to bring the trial implant between the vertebral bodys. If a tight fit is not achieved, repeat the process using incrementally larger trial implants. If the trial implant cannot be in-serted, repeat using incrementally smaller trial implants.
11 DePuy Synthes SynCage-LR Surgical Technique
With the segment fully distracted, the trial implant (and final implant) must fit firmly with a tight press-fit be-tween the endplates so that the disc height is not lost once the distractor is removed.
The image intensifier may be used to check the position of the trial implant, restoration of disc and foraminal height, and overall alignment before selecting the final SynCage-LR implant size.
Note: The distractor must be firmly held in place to prevent its ejection from the disc space and possible injury to adjacent structures. The trial implants are not for implantation and must be removed before insertion of the SynCage-LR.
Preparation and Trial Implantation
SynCage-LR Surgical Technique DePuy Synthes 11
Selection and Packing of Implant
1. Select implant size
Select the final SynCage-LR implant corresponding to the trial implant size.
Notes:• Use caution in handling the SynCage-LR. Damage
to the surface finish and/or teeth can lead to fatigue failure or displacement of the SynCage-LR.
• The SynCage-LR is provided sterile ready for use.
12 DePuy Synthes SynCage-LR Surgical Technique
2. Pack implant with bone graft
Instruments
397.114 Implant Holder, straight, for SynCage-LR
397.117 Implant Holder, angled, for SynCage-LSR
397.131 Packing Block for SynCage-LR, 50 × 55 × 45 mm
397.132 Packing Block for SynCage-LSR, broad
394.585 Cancellous Bone Impactor, 5.5 × 8.5 mm
394.586 Cancellous Bone Impactor, 13.6 × 3.5 mm
After attaching the SynCage-LR to the implant holder, insert it into the appropriate packing block.
It is important to fill the spacer until the filling material protrudes from its perforations in order to ensure enhanced contact with the vertebral endplates.
Use a cancellous bone impactor to firmly pack the filling material into the implant cavities.
Note: The implant holder must be firmly attached to the cage in order to avoid damage to either the im-plant holder or the cage.
Note: Implant Holder 397.117 is an option for use when anatomy makes access difficult with straight instruments.
Selection and Packing of Implant
SynCage-LR Surgical Technique DePuy Synthes 11
1. Insert implant
Instruments
397.113 Distractor, anterior, for SynCage-LR
397.126 Distractor, lumbo-sacral, for SynCage-LSR
Insert the implant into the disc space.
The distractor is used to assist with guiding the implant into the disc space. To ensure that the implant is inserted symmetrically into the disc space, the central line on the distractor blades should be aligned with the anterior midline of the vertebral bodies.
Slide the implant between the distractor blades and into the disc space. Controlled and light hammering on the implant holder may be required to bring the implant be-tween the vertebral bodies. The implant must fit firmly with a tight press-fit between the endplates.
The image intensifier may be used to check the implant position, restoration of disc and foraminal height, and overall alignment.
Note: The distractor must be firmly held in place to prevent its ejection from the disc space and possible injury to adjacent structures. Ensure the implant holder remains tightened to the implant during the entire implant insertion procedure.
Precautions:• The trial implants are not for implantation
and must be removed before insertion of the SynCage-LR.
• Damage to the surface finish and/or teeth can lead to fatigue failure or displacement of the SynCage.
• It is essential that enough material is removed from the intervertebral disc to accommodate the SynCage-LR, otherwise disc material may be dis-placed posteriorly during insertion of the implant.
Implant Insertion
14 DePuy Synthes SynCage-LR Surgical Technique
2. Remove instruments
When the implant is correctly positioned, loosen the locking nut on the distractor handle in order to release the distraction.
Gently remove the distractor while the implant holder holds the implant in position. After the distractor is re-moved, ensure a secure fit by lightly hammering on the implant holder.
Implant Insertion
SynCage-LR Surgical Technique DePuy Synthes 15
3. Verify final implant position
The desired position for the cage is centered within the periphery of the vertebral endplate.
Depending on the size of the vertebrae, the anterior edge of the SynCage-LR will usually be approximately 3–4 mm poste-rior from the anterior edge of the adjacent vertebrae.
Verify the location of the cage relative to the vertebral bodies in the AP and lateral directions using an image intensifier.Three x-ray markers are incorporated into the implant to allow accurate intraoperative and postoperative radio-graphic assessment of the position of the implant. The posterior x-ray marker is located approximately 3 mm from the posterior wall of the cage.
16 DePuy Synthes SynCage-LR Surgical Technique
4. Additional stabilization
Anterior or posterior stabilizationThe SynCage-LR is not designed or intended to be used as a stand-alone device. The use of additional anterior fixation (e.g. ATB) or posterior fixation (e.g. Click’X) is required.
When used in the treatment of spondylolisthesis, poste-rior pedicle screw assisted reduction is usually performed prior to the insertion of the SynCage-LR.
Postoperative carePatients can usually be mobilized once they regain mus-cular control of their trunk on the same day or one day after surgery. However, patients should be cautioned against activities that place unreasonable stress on the lower back until solid bony union has been achieved.
Excessive physical activity and trauma may result in fail-ure, with subsidence of the implant and/or the develop-ment of a non-union.
Implant Insertion
SynCage-LR Surgical Technique DePuy Synthes 17
Implants
SynCage-LR Cage and Trial Implant OverviewImplant sterile packaging and trial implants are colour coded to avoid mismatching.
SynCage-LRDimensions: 24 mm (depth) × 30 mm (width) for smaller and normal vertebral bodies
Anterior Cat. no. Cat. no. Corresponding Trial Implant Colour Height Implant Trial Implant code
12 mm 889.851S 357.160
13.5 mm 889.852S 357.161
15 mm 889.854S 357.162
17 mm 889.856S 357.163
19 mm 889.858S 357.164
SynCage-LR, broadDimensions: 28 mm (depth) × 38 mm (width) for larger vertebral bodies
Anterior Cat. no. Cat. no. Corresponding Trial Implant Colour Height Implant Trial Implant code
12 mm 889.871S 397.121
13.5 mm 889.872S 397.101
15 mm 889.874S 397.102
17 mm 889.876S 397.103
19 mm 889.878S 397.104
SynCage-LSRDimensions: 28 mm (depth) × 38 mm (width) for application in L5-S1
Anterior Cat. no. Cat. no. Corresponding Trial Implant Colour Height Implant Trial Implant code
12 mm 870.909S 357.150
13.5 mm 870.910S 357.151
15 mm 870.911S 357.152
17 mm 870.912S 357.153
19 mm 870.913S 357.154
18 DePuy Synthes SynCage-LR Surgical Technique
Instruments
397.113 Distractor, anterior, for SynCage-LR
397.071 Holder for Trial Implants, straight, detachable
397.114 Implant Holder, straight, for SynCage-LR
397.034 Handle for SynCage Trial Implant, straight
397.035 Handle for SynCage Trial Implant, angled
397.126 Distractor, lumbo-sacral, for SynCage-LSR
397.117 Implant Holder, angled, for SynCage-LSR
SynCage-LR Surgical Technique DePuy Synthes 19
397.131 Packing Block for SynCage-LR, 50 × 55 × 45 mm
397.132 Packing Block for SynCage-LSR, broad
394.585 Cancellous Bone Impactor, 5.5 × 8.5 mm
397.730 Cancellous Bone Impactor B 8.0 mm, round
394.586 Cancellous Bone Impactor, 13.6 × 3.5 mm
397.700 Handle with Quick Coupling
394.570 Cancellous Bone Impactor, straight
21 DePuy Synthes SynCage-LR Surgical Technique
399.420 Hammer 500 g
389.157 Positioner for SynCage
399.100 Bone Spreader, speed lock, width 8 mm, length 210 mm
Instruments
399.130 Bone Spreader, speed lock, width 12 mm, length 270 mm
399.430 Hammer 700 g
SynCage-LR Surgical Technique DePuy Synthes 21
Additional Instruments
SynCage-LR 45°/90°
397.115 Implant Holder for SynCage-LR 45º/90º
397.116 Implant Holder for SynCage-LR 45°/90°, broad
Trial Implants 45°/90°
Dimension, 24 × 30 mm
12 mm 357.170
13.5 mm 357.171
15 mm 357.172
17 mm 357.173
19 mm 357.174
Color code trial implant: green
Dimension, 28 × 38 mm
12 mm 397.105
13.5 mm 397.106
15 mm 397.107
17 mm 397.108
19 mm 397.109
Color code trial implant: violet
22 DePuy Synthes SynCage-LR Surgical Technique
677.796–799 Syncase, for SynCage-LR
Cases
SynCage-LR Surgical Technique DePuy Synthes 21
Synthetic cancellous bone graft substitute: chronOS Bone Void FillerchronOS Bone Void Filler is a bone graft substitute con-sisting of pure -tricalcium phosphate. Its compressive strength is designed to be similar to that of cancellous bone once it has been incorporated and remodeled.1 Based on literature, the use of -tricalcium phosphate in the spinal column is a valuable alternative to allografts and autografts, even when larger amounts are required.2,3
SynCage-LR, 24 × 30 mm, 12°
Article No. Height Filling Volume (mm3) (cm3)
889.851S 12 mm 2720 2.72
889.852S 13.5 mm 3100 3.10
889.854S 15 mm 3520 3.52
889.856S 17 mm 4060 4.06
889.858S 19 mm 4600 4.60
SynCage-LR, large, 28 × 38 mm, 10°
Article No. Height Filling Volume (mm3) (cm3)
889.871S 12 mm 3960 3.96
889.872S 13.5 mm 4600 4.60
889.874S 15 mm 5240 5.24
889.876S 17 mm 6100 6.10
889.878S 19 mm 6980 6.98
Filling Material
1 Gazdag et al. 19952 Muschik et al. 20013 Knop et al. 2006
24 DePuy Synthes SynCage-LR Surgical Technique
Filling Material
SynCage-LSR, 28 × 38 mm, 12°
Article No. Height Filling Volume (mm3) (cm3)
870.909S 12 mm 3940 3.94
870.910S 13.5 mm 4520 4.52
870.911S 15 mm 5160 5.16
870.912S 17 mm 6020 6.02
870.913S 19 mm 6900 6.90
SynCage-LR Surgical Technique DePuy Synthes 25
ResorbableIt is being replaced in the human body by host bone in 6 to 18 months; depending on the indication and the patient’s conditions.2,4–6
OsteoconductiveInterconnected macropores of defi ned size (100–500 μm) facilitate bone formation throughout the entire implant. Interconnected micropores (<10 μm) allow an optimal supply of nutrients.1,7
Osteoinductive with bone marrow The combination of chronOS Bone Void Filler with bone marrow accelerates and enhances osteointegration.4,5
SyntheticHaving a synthetic origin, chronOS Bone Void Filler offers the advantage of uniform quality and unlimited availa-bility.
chronOS Granules Bone Void Filler
Art. No. B (mm) Content (mL)
710.000S 0.5–0.7 0.5
710.001S 0.7–1.4 0.5
710.002S 0.7–1.4 1.0
710.003S 0.7–1.4 2.5
710.011S 1.4–2.8 2.5
710.014S 1.4–2.8 5.0
710.019S 1.4–2.8 10.0
710.021S 1.4–2.8 20.0
710.024S 2.8–5.6 2.5
710.025S 2.8–5.6 5.0
710.026S 2.8–5.6 10.0
710.027S 2.8–5.6 20.0
1 Gazdag et al. 19952 Muschik et al. 20013 Knop et al. 20064 Stoll et al. 20045 Becker et al. 20066 Wheeler et al. 20057 Lu et al. 1999
26 DePuy Synthes SynCage-LR Surgical Technique
Synthetic cancellous bone graft substitute: chronOS PuttychronOS Putty is a synthetic, porous, resorbable and bio-compatible bone graft substitute consisting of chronOS Granules Bone Void Filler and sodium hyaluronate of non-animal origin. The synthetic sodium hyaluronate used in chronOS Putty is designed to provide enhanced handling properties and confers positional stability to the product during handling and use.
Mixing chronOS Putty with bone marrow or blood intro-duces blood cells, growth factors and, in the case of bone marrow, osteoprogenitor cells. Autologous bone marrow features an optimal osteogenic potential.1,2 Per-fusion of the -TCP component of chronOS Putty with bone marrow aspirate has shown clear remodeling of chronOS Bone Void Filler into new host bone 12 weeks postoperatively.1,3
chronOS Putty for Spine
Article number Product name Liquid to add
710.801S chronOS Putty, 1.0cc 0.80 ± 0.25 ml
710.802S chronOS Putty, 2.5cc 2.00 ± 0.5 ml
710.803S chronOS Putty, 5.0cc 4.00 ± 0.5 ml
710.804S chronOS Putty, 10.0cc 8.00 ± 0.5 ml
1 Becker et al. 20062 Block J E, The role and effectiveness of bone marrow in osseous
regeneration. Medical Hypothesis 2005; 65: 740–747.3 Stoll et al. 2004
Filling Material
SynCage-LR Surgical Technique DePuy Synthes 27
Anterior stabilization
01.160.204 Instrument Set for ATB Plate System in Vario Case
The Anterior Tension Band Plate (ATB) is a fixation plate for stabilization of the lumbosacral spine (L1–S1).
Additional Recommended Sets
Posterior stabilizationThe SynCage-LR is intended to be used in combination with posterior fixation (e.g. Click’X).
28 DePuy Synthes SynCage-LR Surgical Technique
Anterior Lumbar Retraction System
01.609.102 Set SynFrame RL, lumbar
187.310 SynFrame Basic System in Vario Case
SynFrame Basic System is a surgical approach and retrac-tion system. It consists of a basic system (basic construc-tion) and modules that are designed for the respective requirements and needs of various indications and/or ap-proach techniques. The SynFrame basic system is always constructed in the same sequence following the same principles. The SynFrame RL is a supplementary module for the access and retraction system SynFrame. It contains radiolucent soft tissue and muscle retractors and semi transparent bone levers for minimally invasive surgery.
Additional Recommended Sets
SynCage-LR Surgical Technique DePuy Synthes 29
Disc Removal System
01.600.100 Proprep Set
A clearly arranged set for intervertebral disc preparation and vertebral body resection for lumbar surgery with an anterior approach:• Compact but comprehensive: contains all instruments
required for intervertebral disc preparation and verte-bral body resection.
• Designed to simplify the entire anterior discectomy and corpectomy thanks to angled instruments with which even the posterolateral regions of the intervertebral discs can be reached.
• Designed for use in extensively collapsed segments as the instruments have a low profile.
• The instrument length is designed for anterior surgery and for patients with a high BMI.
• Enhanced instrument control thanks to silicon handles that can be gripped with two hands.
11 DePuy Synthes SynCage-LR Surgical Technique
Aebi M, Arlet V, Webb JK (2007): AOSpine Manual (2 vols), Stuttgart, New York: Thieme
Aebi M, Thalgott JS, Webb JK (1998). AO ASIF Principles in Spine Surgery. Berlin: Springer.
Becker S, Maissen O, Ponomarev I, Stoll T, Rahn B, Wilke I (2006) Osteopromotion by a -Tricalcium Phosphate/Bone Marrow Hybrid Implant for Use in Spine Surgery. Spine 31 (1): 11–17
Block J E, The role and effectiveness of bone marrow in os seous regeneration. Medical Hypothesis 2005; 65: 740–747.
Gazdag AR, Lane JM, Glaser D, et al. (1995) Alternatives to autogenous bone graft: efficacy and indications. J Am Acad Orthop Surg 3(1): 1–8.
Knop C, Sitte I, Canto F, Reinhold M, Blauth M (2006): Successful posterior interlaminar fusion at the thoracic spine by sole use of -tricalcium phosphate. Arch Orthop Trauma Surg, 126: 204–210
Lu Jx, Flautre B et al. (1999) Role of interconnections in porous bioceramics on bone recolonization in vitro and vivo. J Mater Sci Mater Med 10: 111–120.
Muschik M, Ludwig R, Halbhubner S, Bursche K, Stoll T (2001) -tricalcium phosphate as a bone substitute for dorsal spinal fusion in adolescent idiopathic scoliosis – preliminary results of a prospective clinical study. Eur Spine J 10: 178–84.
Stoll T, Maissen O, Meury T, Becker S (2004) New aspects in osteoinduction. Mat.-wiss. u. Werk stofftech 35: 198–202
Wheeler D. (2005) Grafting of massive tibial subchondral bone defects in a Caprine Model using -Tricalcium phosphate versus autograft. J Orthop Trauma 19(2): 85–91.
Bibliography
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Not all products are currently available in all markets.
This publication is not intended for distribution in the USA.
All surgical techniques are available as PDF files at www.depuysynthes.com/ifu ©
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