SURGICAL TECHNIQUE. C-Plate ANTERIOR CERVICAL PLATE

Transcription

1 SURGICAL TECHNIQUE C-Plate ANTERIOR CERVICAL PLATE

2 SURGICAL TECHNIQUE C-Plate Table of contents page Step 1 - Disc location and vertebral space preparation Step 2 - Plate selection and bending Step 3 - Plate positioning Step 4 - Screw path preparation and creation a. Drill guide positioning b. Screw path creation Option. Depth measurement Tapping Step 5 - Screw insertion Step 6 - Final locking Option - Revision

3 Step 1 Disc location and vertebral space preparation The approach of the intersomatic space can be realised after identifying the affected level under fluoroscopy. The surgical protocol and the technique used for the exposure of the intersomatic space are the same as for the standard anterior approach for cervical vertebral surgery. Place the retractor on the level to be treated, distract the intersomatic space and proceed to disc resection. Note: The retractor fixation pins must be parallel to the vertebral endplates. Be careful to take off all the anterior osteophytes for the plate to be in perfect congruence with the anterior wall of the vertebrae. Note: It is not needed to resect all the annular disc tissue laterally. Repeat the procedure on the different levels to be treated. Remove both the retractor and the retractor fixation pins

4 SURGICAL TECHNIQUE C-Plate Step 2 Plate selection and bending First, determine the plate length and then use the plate holder to place it on the spine. Be sure that the defined length is appropriate and that the plate isn t in contact with the adjacent discs. The plates are pre-formed; however, more lordosis can be given using the plate bender. Elastic locking ring Bending Unbending Important: - The plate bending must be performed between the two self-locking mechanisms, being careful not to damage them. - Do not bend a plate with a length inferior to 46 mm. - Never put a plate that has been bended or unbended back into the implant rack.

5 Step 3 Plate positioning Insert the temporary fixation pin into the fixation pin driver and stabilize the plate on the vertebrae. or Note: It is advised to put the two temporary fixation pins in diagonal onto the plate in order to ensure better temporary stability. When the double-barrel drill guide is used, the temporary fixation pins are placed side by side. Simple drill guide use Double-barrel drill guide use 4-5

6 SURGICAL TECHNIQUE C-Plate Choice between the semi-fixed and variable screws Two types of screws exist: semi-fixed and variable. These screws are available in two diameters (3.5 mm and 4.0 mm) and in five lengths (10 to 18 mm by increment of 2 mm). 3,5 mm 4 mm Semi-fixed screws The two types of screws can be used on the same assembly according to surgeon preference and the desired angulation between the screws and the plate. Variable screws Note: The screw placed in the central hole of the plate must be a variable screw. Screw insertion angulation Sagittal plan Axial plan Variable screws Semi-fixed screws Variable screws Semi-fixed screws

7 Step 4 Screw path preparation and creation In order to create the screw path, two steps must be performed: 1 - The choice between two drill guides: This choice will depend on the screw type to insert in order to ensure their sliding under the self-locking mechanism. Semi-fixed screws: Use the double-barrel drill guide Variable screws: Use the simple drill guide 2 - The choice between two types of drill bits: Fixed-stop drill bit for screws with a length of 14 mm Ø3.5 mm or Ø4.0 mm Adjustable drill bit Ø3.5 mm or Ø4.0 mm Adjustable stop 6-7

8 SURGICAL TECHNIQUE C-Plate Step 4a Drill guide positioning Important: Make sure that there are no temporary fixation pins in the holes where the drill guide will be placed. Place the drill guide on the plate. Double-barrel drill guide Important: The drill guide spurs must be in contact with the plate. If not, the angulation given to the screw path may be unpredictable, potentially prohibiting final locking from occuring (self locking mechanism sliding over screw heads). Simple drill guide Spur

9 Step 4b Screw path creation Choose the drill bit according to the screw diameter. Two different types of drill bits are available: fixed stop drill bit Option A or Adjustable stop drill bit Option B Option A Fixed stop drill bit Important: The fixed stop drill bit can only be used with 14 mm screws. Assemble the quick-connect handle and the drill bit. Insert the drill bit into the drill guide that has been positioned beforehand and drill the screw path to the mechanical stop. Remove the drill bit first and then the drill guide. Mechanical stop 8-9

10 SURGICAL TECHNIQUE C-Plate Option B Adjustable stop drill bit Assemble the quick-connect handle and the adjustable drill bit. «Unlock» Line up the two arrows of the adjustable stop to the unlock position and screw the stop on the drill bit to the needed position. Lock lining up the two arrows into the lock position. «Lock» Note: The stop can be adjusted from 10 to 20 mm (by increment of 1 mm). Insert the drill bit into the drill guide that has been positioned beforehand and drill the screw path to the mechanical stop. Remove the drill bit first and then the drill guide. Mechanical stop

11 Option Depth measurement Confirm the screw length to be inserted using the depth gauge. Important: The screw length includes the head and the thread. Length Tapping Although the screws are self-tapping, complementary tapping can be conducted according to the surgeon s needs and habits. Choose the type of tap to use according to the screw diameter to be inserted. Two types of taps are available: fixed stop tap and adjustable stop tap. Note: the use of the taps is identical to use of the drill bits during step 4b. Important: The fixed stop tap can only be used with the 14 mm screws. Fixed stop tap for 14 mm screws Ø3.5 mm or Ø4.0 mm Adjustable stop tap Ø3.5 mm or Ø4.0 mm Adjustable stop 10-11

12 SURGICAL TECHNIQUE C-Plate Step 5 Screw insertion Grab the chosen screw in the implant rack using the selfretaining screw driver and screw it in the drill axis that was achieved beforehand taking care not to perform the final locking (screw locking under the elastic ring). Important : ne pas effectuer le serrage final (blocage des vis sous le clip) tant que toutes les vis ne sont pas mises en place. Important: - The screw placed into the central hole of the plate must be a variable screw. - Screw insertion into the central hole must be perpendicular to the plate.

13 Step 6 Final locking X-Ray It is advised to check with fluoroscopy before final screw locking. Achieve final locking by tightening the screws until they slide under the clip. They are then placed and secured. Important: The C-Plate locking mechanism is correctly accomplished when two controls are done: - Tactile and auditory controls of the clip sliding over the screw heads when final locking is performed - Visual control of the screw head sliding under the self-locking mechanism. Final screw locking Note: In case the clip does not return to its initial position, insert the temporary fixation pin tip between the two elastic parts of the clip in order to position them back on the screw heads. Conduct a final control X-Ray 12-13

14 SURGICAL TECHNIQUE C-Plate Option Revision Use the screw remover to unscrew the screws of the assembly. Thanks to the screw driver design, it is possible to slightly close the clip so that the screw head sliding out of the locking mechanism will be easier. Maintain the plate with the plate holder during the removal of the last screw. Caution: This procedure definitively damages the use of the C-Plate locking mechanism. Those plates must not be used again.

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16 France Technopôle de l Aube BP Troyes Cedex 9 France +33 (0) China Beijing Global Trade Center #36 North Third Ring Road East, Unit 06, Level 19, Building A, Dongcheng District, Beijing, China, Brazil Av. Pereira Barreto, 1395 Torre sul - CJ Bairro Paraiso Santo André - São Paulo CEP : Brazil United States 4030 West Braker Lane, Suite 360 Austin, Texas Ref: CP ST 1 EN A. LDR, LDR Spine, LDR Médical, BF+, BF+(ph), Easyspine, C-Plate, SpineTune, Laminotome, MC+, Mobi, Mobi-C, Mobi-L, Mobidisc, ROI, ROI-A, ROI-MC+, ROI-T, ROI-C and vertebridge are trademarks or registered trademarks of LDR Holding Corporation or its affiliates in France, the United States or other countries.