Pangea Degenerative Spine System. Top Loading Preassembled Pedicle Screw System for Posterior Stabilization of the Thoracolumbar Spine.

Transcription

1 Technique Guide Pangea Degenerative Spine System. Top Loading Preassembled Pedicle Screw System for Posterior Stabilization of the Thoracolumbar Spine.

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3 Contents Introduction AO ASIF Principles 4 Indications and Contraindications 6 Product Information Set Configuration 7 Implants 8 Instruments 12 Surgical Technique Screw Insertion 18 Posterior Interbody Fusion 23 Rod Insertion 24 Rod Reduction Techniques 26 Close Construct 29 Compress or Distract 32 Apply Final Tightening 34 Additional Techniques 35 Warning This description is not sufficient for immediate application of the instrumentation. Instruction by a surgeon experienced in handling this instrumentation is highly recommended. Synthes 1

4 Pangea Degenerative Spine System. Top Loading Preassembled Pedicle Screw System for Posterior Stabilization of the Thoracolumbar Spine. The Pangea Degenerative Spine System is a posterior pedicle screw fixation system (T1-S2) intended to provide precise and segmental stabilization of the spine in skeletally mature patients. Pangea dual-core screws Dual-core thread design for optimized bone purchase: Cortical thread engages the pedicle, cancellous thread engages the vertebral body Transition zone for core diameter change Constant outer diameter Double-lead thread speeds insertion of 4, 5, 6 and 7 mm screws Self-tapping profile Blunt, threaded tip for safer insertion Constant outer diameter Cortical thread Transition Cancellous thread 2 Synthes Pangea Degenerative Spine System Technique Guide

5 Locking cap features Quarter turn captures rod Ridges under saddle grip the rod Self-aligning saddle Visual markings for alignement Tactile feedback for insertion and 1 4 turn engagement Polyaxial head Top loading for easy rod introduction Offers 25 of angulation about the axis of the screw allowing the implant to adjust readily to the rod Rod snaps into head to stabilize construct before locking cap installation Curved rods 6.0 mm curved rods 35 mm to 85 mm lengths in small increments reduce the need to contour or cut Same mechanical properties as straight rods Synthes 3

6 AO ASIF Principles In 1958, the AO ASIF (Association for the Study of Internal Fixation) formulated four basic principles 1, which have become the guidelines for internal fixation. They are: Anatomical reduction Stable internal fixation Preservation of blood supply Early, active pain-free mobilization The fundamental aims of fracture treatment in the limbs and fusion of the spine are the same. A specific goal in the spine is returning as much function as possible to the injured neural elements. 2 AO ASIF Principles as Applied to the Spine 3 Anatomical reduction Restoration of normal spinal alignment to improve the biomechanics of the spine. Stable internal fixation Stabilization of the spinal segment to promote bony fusion. Preservation of blood supply Creation of an optimal environment for fusion. Early, active pain-free mobilization Minimization of damage to the spinal vasculature, dura, and neural elements, which may contribute to pain reduction and improved function for the patient. 1 M.E. Müller, M. Allgöwer, R. Schneider, and H. Willenegger: AO Manual of Internal Fixation, 3rd Edition. Berlin; Springer-Verlag Ibid. 3 M. Aebi, J.S. Thalgott, and J.K. Webb. AO ASIF Principles in Spine Surgery. Berlin; Springer-Verlag Synthes Pangea Degenerative Spine System Technique Guide

7 Spine principle for posterior fixation Technique feature Clinical importance Anatomical reduction Precontoured rods mimic spinal curvature Restores normal spinal curvature Polyaxial head offers ±25 of angulation to reduce rod contouring and provide optimal rod placement Restores normal spinal curvature Stable internal fixation Dual-core screw design improves fixation. Cortical thread engages the pedicle and cancellous thread engages the vertebral body Optimizes pull-out strength to create a stable segment, thereby promoting fusion and/or maintenance of decompression of neural elements Specialized saddle in locking cap Resists rod slip. Maximizes strength of construct Preservation of blood supply Simple quarter-turn locking cap Offers ease and speed in building the construct, leading to shorter operative times Early, active pain-free mobilization Small head profile and tapered body Minimizes trauma to patient and may lead to pain reduction and improved function Synthes 5

8 Indications and Contraindications The Pangea Degenerative Spine System is a posterior pedicle screw fixation system (T1 S2) intended to provide precise and segmental stabilization of the spine in skeletally mature patients. Indications Degenerative disc disease Spondylolisthesis Trauma (i.e., fracture or dislocation) Tumour Stenosis Pseudoarthrosis Failed previous fusion Contraindications Fractures and tumours with loss of anterior support 6 Synthes Pangea Degenerative Spine System Technique Guide

9 Set Configuration Vario Case for Basic Instruments Pangea Polyaxial, with Lid, without Contents Pangea Polyaxial Basic Instruments in Vario Case Vario Case for Implants Pangea Polyaxial, with Lid, without Contents Pangea Polyaxial Implants in Vario Case Optional Vario Case for Optional Instruments Pangea Polyaxial, with Lid, without Contents Pangea Polyaxial Optional Instruments in Vario Case Synthes 7

10 Implants Pangea dual-core screws Preassembled polyaxial head offers 25 of angulation Dual-core thread design Constant outer diameter Double-lead thread speeds insertion Self-tapping profile Blunt, threaded tip for safer insertion 1. Pedicle Screw Pangea Polyaxial, preassembled, Titanium Alloy (TAN) Art. No. Outer Cortical Cancellous lengths core core mm mm mm mm Locking Cap Pangea, Titanium Alloy (TAN) Art. No Synthes Pangea Degenerative Spine System Technique Guide

11 3. Rods, Titanium mm rods, curved Lengths 35 mm to 85 mm in 5 mm increments reduce the need to contour or cut Art. No. Length (mm) mm rods, straight Art. No. Length (mm) Synthes 9

12 Implants 4. Transverse connectors, low profile, for Rods 6 mm, Titanium Alloy (TAN) Transverse connector(s) with adjustable length and angle may be added to the construct. Art. No. Length (mm) Synthes Pangea Degenerative Spine System Technique Guide

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14 Instruments Taps for dual-core Screws, with 6 mm hex coupling Art. No (mm) Used with Ratchet T-Handle with Low Toggle with Hexagonal Coupling 6.0 mm ( ) for tapping a hole for Pangea screws. Instruments for screw insertion Screwdriver Stardrive, T25, with T-Handle, for Pangea Screwdriver Stardrive, T25, with straight handle, for Pangea An alternate screw insertion method for Pangea screws Screwdriver Shaft Stardrive, T25, long, with Hexagonal Coupling 6.0 mm, for Pangea Used with long Pangea instruments Screwdriver Shaft Stardrive, T25, with Hexagonal Coupling 6.0 mm, for Pangea Screwdriver Shaft Stardrive, T25, short, with Hexagonal Coupling, for Pangea Can not be used in combination with other instruments. 12 Synthes Pangea Degenerative Spine System Technique Guide

15 Alternate screw insertion methods for Pangea screws Instrument shafts mate with handles that have 6 mm hexagonal couplings Ratchet T-Handle with Low Toggle with Hexagonal Coupling 6.0 mm Used with either the 6 mm hexagonal coupling taps for preparing bone or screwdriver shafts for insertion of Pangea screws and locking caps Handle with Ratchet, straight, with Quick Coupling, for Pangea An alternate method used with a 6 mm hexagonal coupling screwdriver shaft for insertion of Pangea screws and locking caps Retaining Sleeve for Pangea Polyaxial screws Used with screwdrivers and screwdriver shaft ( , , ). Rigidly couples screwdriver and polyaxial screw during insertion Stabilization Sleeve for Pangea Polyaxial screws Optionally used with screwdrivers and screwdriver shaft ( , , ). Stabilizes polyaxial head during screw insertion. Synthes 13

16 Instruments Instruments for rod preparation and insertion Bending Template 6.0 mm, length 150 mm, single use Used to determine the length and contour of the rod Rod Bender for Rods 6.0 mm, with Radius Adjustment Contours the rod, using the knob to adjust the bend radius Holding Forceps for Rods 6.0 mm, length 290 mm Used to place and manoeuvre the rod into the implant opening Holding Forceps, straight, for Rods 6.0 mm Used to place the rod into the Pangea head. Narrow jaws allow rod insertion into tight spaces between screws Rod Pusher/Counter Torque for Pangea Helps seat the rod. Provides counter torque on the rod during final tightening. 14 Synthes Pangea Degenerative Spine System Technique Guide

17 Rod Pusher for Rods 6.0 mm Assists in placing rod into implant opening Rod Persuader for Pangea Introduces the rod into the Pangea screw head and facilitates locking cap introduction. Provides 10 mm of reduction Rocker Fork Pangea, small, straight shaft Provides vertical reduction of rod into implant Rocker Fork Pangea, small, curved shaft Provides vertical reduction of rod into implant requiring less rod exposure. Instruments for construct assembly Locking Cap Driver with T-Handle, for Pangea Used with screwdrivers and screwdriver shaft ( , , ) to drive Pangea Locking Cap through 1 4 turn lock Torque-limiting Handle, 10 Nm, for Pangea Used with a 6 mm hexagonal coupling screw driver shaft for final tightening of the locking cap to apply a torque of 10 Nm to the locking cap setscrew. Synthes 15

18 Instruments Template for Transverse Connectors low profile, for Rods 6.0 mm Helps to determine appropriate transverse connector length Screwdriver, hexagonal, small, 2.5 mm, length 293 mm Used to secure transconnector. For distraction and compression Distractor Pangea, with Hinge Provides distraction to ease insertion of interbody implants. Hinged handles allow greater visibility during interbody fusion techniques Compression Forceps, for Lumbar Spine Used to apply compression across a Pangea assembly before final tightening Distraction Forceps, for Lumbar Spine Used to apply distraction across a Pangea assembly. Wedge shaped tips allow distraction between closely spaced implants. 16 Synthes Pangea Degenerative Spine System Technique Guide

19 Instruments for extraction Remobilization Tool for Pangea Remobilizes Pangea screw heads after setscrew tightening Extractor for setscrew 4.0 mm Mates with square tip of Extender, 6 mm hex coupling ( ) and Ratchet T-Handle ( ) to remove damaged Pangea screw or cap Extender for No Used with Extractor for setscrew 4.0 mm ( ). Synthes 17

20 Screw Insertion 1 Open pedicles and determine screw lengths Required instruments Pedicle Awl for Screws 4.0 to 7.0 mm, length 255 mm Pedicle Probe 3.8 mm, straight, length 240 mm Optional Instruments Pedicle Awl for Screws 8.0 and 9.0 mm, length 255 mm Pedicle Probe for Screws 8.0 and 9.0 mm, length 240 mm Locate pedicles as described in AO ASIF Principles in Spine Surgery 1. Use an awl to perforate the outer cortex of the pedicles. Use a probe to open the pedicle canal. The markings on the probes yield visual indication of the pedicle canal depth. Pangea screws are self-tapping for ease of insertion. Therefore, it is not necessary to tap pedicles. In clinical cases that require tapping, taps for pedicle screws and a ratchet T-handle are available. 1 M. Aebi, J.S. Thalgott, and J.K. Webb. AO ASIF Principles in Spine Surgery. Berlin; Springer-Verlag Synthes Pangea Degenerative Spine System Technique Guide

21 2 Prepare site for screw head Required instruments Reamer Insert the tip of the Reamer into the prepared hole. Use rotating movements to remove all interfering bone, and ensure that enough space exists to allow free mobility of the screw head. Repeat for each pedicle site to be instrumented. Synthes 19

22 3 Insert pedicle screws Required instruments Ratchet T-Handle with Low Toggle with Hexagonal Coupling 6.0 mm Screwdriver Shaft Stardrive, T25, with Hexagonal Coupling 6.0 mm Use the Ratchet T-Handle and the self-retaining Screwdriver Shaft to pick up a screw from the screw rack. Place the screwdriver tip firmly into the star recess and pick up the screw. Insert the screw into the prepared pedicle. Repeat for each screw site. Option A: Inserting screw with Stabilizing Sleeve Required instruments Stabilization Sleeve for Pangea Polyaxial screws If there is soft tissue in the path accessing the pedicle, the Stabilization Sleeve may be used to stabilize the head and keep it from rotating during insertion. Load the Stabilization Sleeve on the Stardrive shaft. Place the screwdriver tip firmly into the star recess of the screw in the screw rack and slide the Stabilizing Sleeve down into the screw head. The sleeve may be held during screw insertion to prevent the head from turning as the screw advances. 20 Synthes Pangea Degenerative Spine System Technique Guide

23 Option B: Inserting screw with Retaining Sleeve Required instruments Retaining Sleeve for Pangea Polyaxial screws If it is necessary to exert lateral forces on the screw during insertion, the Retaining Sleeve provides rigid coupling to keep the screw secure. Push button and slide sleeve Push knurled sleeve To assemble the Retaining Sleeve on the Screwdriver Shaft press and hold down the assembly button while sliding the sleeve toward the handle until it stops. Let go off the button then push the outer knurled sleeve toward the handle. Ensure that the tensioning knob is loosened. Place the screwdriver tip firmly into the star recess of the screw in the screw rack. Turn the retaining sleeve T-handle to align the tips with the rod slot. Push the sleeve down to capture the screw and pick up the screw. Loosening tensioning knob After the screw is loaded, if additional screw coupling to the driver is desired, the tensioning knob may be tightened to apply more retaining force on the screw. Tightening tensioning knob Synthes 21

24 Insert the Pangea screw into the prepared pedicle. The outer sleeve may be held during screw insertion. Note: Do not press the assembly button during screw insertion. If this happens, remove the screw, reassemble the sleeve on the shaft and reload the screw. To release the sleeve pull up on the outer sleeve and remove the screwdriver. Repeat for each screw. 22 Synthes Pangea Degenerative Spine System Technique Guide

25 Posterior Interbody Fusion Required instruments Distractor Pangea, with Hinge If posterior interbody fusion is performed at this time, the Distractor with Hinge may be placed between Pangea screws to distract the interbody space. Position screws at similar height. Engage one distractor leg below a polyaxial screw head. Engage second distractor leg below the second screw head. Fold distractor handle. Distract, and tighten speed nut. Perform interbody procedure. Remove Distractor and adjust screw heights to final positions. Synthes 23

26 Rod Insertion 1 Select and contour rod Required instruments Bending Template 6.0 mm, length 150 mm, single use Rod Bender for Rods 6.0 mm, with Radius Adjustment Determine rod length and curvature using the Bending Template. The polyaxial Pangea screw head compensates for some lateral screw offset. Select the appropriate length and, if necessary, bend the rod using the Rod Bender. Note: Repeated bending can weaken the rod. 24 Synthes Pangea Degenerative Spine System Technique Guide

27 2 Insert rod Optional Instruments Holding Forceps for Rods 6.0 mm, length 290 mm Holding Forceps, angled, for Rods 6.0 mm Holding Forceps, straight, for Rods 6.0 mm Insert the rod into the Pangea head using one of the holding forceps listed above. Typically a distinct snap is felt when the rod is pushed into the screw head. The retention feature is designed to provide temporary hold during assembly. Note: It is not necessary to feel the snap if the rod is seated. Synthes 25

28 Rod Reduction Techniques The rod must be seated in the Pangea head in order to engage the locking cap. There are three alternative instruments. a Rod pushers Required instruments Rod Pusher/Counter Torque for Pangea Rod Pusher for Rods 6.0 mm Use the Rod Pusher/Counter Torque or the Rod Pusher to push the rod firmly into the screw head. For constructs with two or more levels, begin with the central screw. 26 Synthes Pangea Degenerative Spine System Technique Guide

29 b Rocker forks Required instruments Rocker Fork Pangea, small, straight shaft Rocker Fork Pangea, small, curved shaft Use the Rocker Fork with straight shaft or Rocker Fork with curved shaft. Hook the fork under the head s reduction features from a cranial/caudal approach and rock it away from the screw to seat the rod into the head. The Rocker Fork with curved shaft requires less rod exposure, but more access to engage the head. Note: Placing the fork on the side where the rod is higher is more effective at getting the rod seated evenly in the implant. Synthes 27

30 c Persuader Required instruments Rod Persuader for Pangea Use the Rod Persuader and hook the tips of the Persuader under the head s reduction features from a cranial/caudal approach. Centre the Persuader over the head and squeeze the handle to seat the rod in the head. Engaging the Persuader Tip: If necessary the handle on the Persuader may be reversed to allow better access. Persuading the rod 28 Synthes Pangea Degenerative Spine System Technique Guide

31 Close Construct 1 Attach locking caps Required instruments Screwdriver Shaft Stardrive, T25, with Hexagonal Coupling 6.0 mm, for Pangea Torque-limiting Handle, 10 Nm, for Pangea Rod Pusher/Counter Torque for Pangea Locking Cap Driver with T-Handle, for Pangea Cap insertion should be done using guidance through the Rod Pusher/Counter Torque or with a rocker fork engaged or through the Persuader. Attach the Screwdriver Shaft to the Torque-limiting Handle. Slide the Locking Cap Driver over the Screwdriver Shaft to the top groove. Insert the screwdriver tip firmly into a Pangea locking cap and remove the cap from the module. Align black marks on the locking cap parallel with the rod. When the cap is in the correct position, it will drop slightly into the Pangea head. Push down on the cap to snap it into the head. Insert cap into head Synthes 29

32 Close construct Rotate the screwdriver 1 4 turn to the right to engage the cap and capture the rod. There is a distinct snap as the cap turns into place. The black marks on the locking cap are now perpendicular to the rod. The rod is free to slide within the head and the head retains polyaxial mobility. Note: All locking caps should be in place before tightening any of the setscrews. Close construct with 1 4 turn If provisional tightening is desired, turn the screwdriver further to drive the setscrew down and lock the rod and the head. Tighten until the Torque-limiting Handle slips. Tighten construct by releasing setscrew Repeat for all locking caps. Note: It is possible to visually identify locking caps that have had their initial preload disturbed by examining the alignment of the setscrew to the cap. If the etch marks are not aligned, the setscrew is not ready to carry the cap through the 1 4 turn. The cap driver would be used in this situation. Set Not Set 30 Synthes Pangea Degenerative Spine System Technique Guide

33 Alternatively: If the setscrew turns freely within the cap and/or the locking caps have had their initial preload disturbed as indicated by the alignement of the etch marks, use the Locking Cap Driver with T-handle to turn the cap. Required instruments Locking Cap Driver with T-Handle, for Pangea Place the screwdriver tip into the setscrew. Slide the Locking Cap Driver down onto the top of the setscrew. Thread the locking cap driver clockwise onto the top of the setscrew until it is snug. Press against a surface to avoid pushing the cap off the shaft. Insert screwdriver tip into setscrew Thread locking cap driver onto setscrew Insert locking cap as described in the previous section with etch mark parallel to the rod. Turn the Locking Cap Driver clockwise to rotate the cap 1 4 turn while holding the handle. Etch parallel to rod, cap inserted Etch crossing rod, cap closed Note: Unthread the Locking Cap Driver counterclockwise (holding on to screwdriver handle) and retract it before driving the setscrew further with the Stardrive screwdriver to avoid locking of the instruments to the locking cap. Unscrew Retract Synthes 31

34 Compress or Distract Controlled compression or distraction is possible by applying forces at the posterior aspect of the vertebral bodies or across the entire vertebral body. Lordotic compression will control the amount of resulting lordosis. Parallel compression will result in more uniform forces across to the anterior aspect of the vertebral body. Lordotic compression Parallel compression Required instruments Compression Forceps, for Lumbar Spine Distraction Forceps, for Lumbar Spine Screwdriver Shaft Stardrive, T25, with Hexagonal Coupling 6.0 mm, for Pangea Rod Pusher/Counter Torque for Pangea Lordotic compression/distraction Lordotic compression or distraction with mobile Pangea screw heads is only possible when the locking cap setscrews have not tightened. Use the Compression Forceps to achieve compression, or the Distraction Forceps to achieve distraction. After compression/distraction has been achieved, tighten the setscrew with the Screwdriver Shaft Stardrive. If final tightening is desired insert the Screwdriver Shaft attached to the Torque-limiting Handle through the Rod Pusher/Counter Torque and tighten setscrew. Note: The Distraction Forceps have narrow wedge tips that can be pushed between very tightly spaced implants 32 Synthes Pangea Degenerative Spine System Technique Guide

35 Parallel compression/distraction Parallel compression or distraction is possible with locked polyaxiality in the Pangea screw heads where the locking cap setscrews have been tightened and loosened. Use the Compression Forceps to achieve compression, or Distraction Forceps to achieve distraction, then tighten the setscrews by inserting the Screwdriver Shaft through the Rod Pusher/Counter Torque. Tighten the setscrew while holding the Rod Pusher/Counter Torque. Note: Do not use the Torque-limiting Handle to loosen setscrews. Repeat as desired for each segment. Synthes 33

36 Apply Final Tightening Required instruments Rod Pusher/Counter Torque for Pangea Screwdriver Shaft Stardrive, T25, with Hexagonal Coupling 6.0 mm, for Pangea Torque-limiting Handle, 10 Nm, for Pangea Place the Rod Pusher/Counter Torque over the Pangea screw head. Attach the Screwdriver Shaft to the Torque-limiting Handle and insert the shaft through the Rod Pusher/Counter Torque and into the locking cap setscrew. Tighten to the audible click, which indicates that 10 Nm of torque has been applied. Repeat for all locking caps. Notes: The Locking Cap Driver can be used to help center the Screwdriver Shaft. Do not use the Torque-limiting Handle to loosen setscrews. To facilitate fusion, bone graft is often applied in the lateral gutters. A suitable bone graft substitute (e.g. chronos, DBX, Calceon 6) may be used by itself or in combination with autograft. The construct shown is illustrated with chronos osteoconductive -tricalcium phosphate scaffold, perfused with bone marrow aspirate. 34 Synthes Pangea Degenerative Spine System Technique Guide

37 Additional Techniques Adding transverse connectors Required instruments Template for Transverse Connectors low profile, for Rods 6.0 mm Screwdriver, hexagonal, small, 2.5 mm, length 293 mm Transverse connector(s) may be added to the construct. Use the Template for Transverse Connectors to measure the distance between the two rods. Choose a transverse connector of appropriate length. Assure that the transverse connector setscrews are not advanced and apply the transverse connector to the rod. Use the small Screwdriver 2.5 mm to tighten the setscrews on each end. For transverse connectors with angular adjustment, tighten the setscrew to lock the angle between the rods. When using an adjustable length transverse connector, slide the ends to the appropriate length and tighten the centre setscrew. Note: If any part of the construct requires further adjustment, all transverse connector setscrews must be loosened. After final adjustment, retighten the setscrews. Synthes 35

38 Additional techniques Removal of locking caps Required instruments Screwdriver Shaft Stardrive, T25, with Hexagonal Coupling 6.0 mm, for Pangea Insert a Stardrive Screwdriver into the setscrew of the locking cap. Turn the screwdriver counterclockwise until the cap rotates back to its original insert position with the black marks parallel to the rod. Tilt the shaft along the rod and lift the cap out. Note: Do not use the Torque-limiting Handle to remove or loosen caps or screws. Remobilization of Pangea screw heads Required instruments Remobilization Tool for Pangea The polyaxial heads can be remobilized with the remobilization tool. After removing the locking caps and the rod, insert the remobilization tool into the Pangea screw head, and squeeze the handle completely. Angulate the tool to loosen angulation. 36 Synthes Pangea Degenerative Spine System Technique Guide

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40 Presented by: SE_ AB Synthes 2007 Pangea is a trademark of Synthes Subject to modifications.