Aesculap Spine CeSpace. Anterior Cervical Interbody Fusion System

Transcription

1 Aesculap Spine CeSpace Anterior Cervical Interbody Fusion System

2 Philosophy CeSpace is a spacer used for cervical interbody fusion. It is indicated for the treatment of degenerative diseases of the cervical disc and can be used for cervical fusion The central opening in the implant can optionally be filled with spongiosa or bone substitute to further enhance the interbody fusion. in the C3 to C7 region. The main goal is the reconstruction and maintenance of the disc height. CeSpace implants are available in two Combined with ergonomic instrumentation, CeSpace is the solution for cervical interbody fusion. different material types, depending on the preference of the surgeon: CeSpace Titanium is made of a titanium alloy and is coated with our proven Plasmapore coating. CeSpace PEEK is made of biocompatible PEEK-OPTIMA with two integrated markers which enable effective x-ray control. 2

3 The shape of the CeSpace implant has been designed to correspond to the anatomy of the cervical intervertebral space. Implant Design Its "semi-round" form ensures a maximum contact area between the implant and the vertebral body endplates while the opening yields enough capacity to be filled with spongiosa or bone substitute, if desired. CeSpace is offered in several different shapes tailored to meet particular requirements of the cervical spine. All implants are lordotic in shape (5 ) and provided in two different implant geometries (ø 14 mm x 11.5 mm or ø 16 mm x 13.5 mm). Implant Geometry CeSpace Titanium is offered in heights ranging from 4 mm to 7 mm while CeSpace PEEK implants are available from 4 mm to 8 mm height. PEEK Diameter Diameter Titanium Depth 2:1 Depth 2:1 Toothed Surface Fixation Crowns 5 Lordotic Implant Shape 5 Lordotic Implant Shape 3

4 CeSpace Implant Titanium The enabling feature of this cervical interbody implant is a solid titanium core (Fig. 1). The core is coated with microporous Plasmapore to increase its surface area, thereby maximizing the area of contact between the implant and the vertebral body. Primary stability is achieved by the cranial and caudal fixation crowns of the implant. After CeSpace is implanted, these elements are pressed into the adjacent vertebrae, thereby ensuring a firm and secure anchorage of the implant in the intervertebral space. One to two days postoperative x-rays illustrate the fixation elements have completely embedded themselves into the vertebral body endplates. Secondary stability is achieved through the material properties of the Plasmapore coating. It provides an optimal gripping structure for bony ingrowth into the surface of the implant during the bone remodeling phase. A firm bony connection between the vertebral body endplates and the implant coating is essential for cervical fusion. Plasmapore is a proprietary technology that has been proven to be an effective environment for bony ingrowth into the surface of the implant. The effective bony ingrowth is achieved by the collective balance of poresize, porosity and roughness. To build the Plasmapore coating, Aesculap repeatedly sprays the raw material with pure titanium powder thereby applying successive layers (Fig. 2). The molten titanium powder settles on the implant surface, cools and develops a firm form-lock between the core and the coating. Fig. 1 Fig. 2 4

5 PEEK The material used is biocompatible PEEK-OPTIMA, which was introduced by Invibio in PEEK stands for PolyEtherEtherKetone. PEEK-OPTIMA is manufactured under rigorous conditions for purity and strict adherence to quality guidelines, and is licensed by the FDA for use as a medical implant material. The use of PEEK-OPTIMA as an orthopedic device material enjoys increased popularity in recent years due to the material s unique combination of characteristics. It s properties include radiolucency, high mechanical strength, biocompatibility and compatibility with standard sterilization methods. The intrinsic radioscopic transparency of the material gives it permeability on x-rays and CT scans, making it possible to view bone growth adjacent to the implant. This allows quick and simple assessment of the bone structure and progress towards bone fusion. To verify the position of our PEEK-implants on radioscopic images, we have enclosed non-radioluced pins which serve as location markers (Fig. 1). Of particular interest is the modulus of elasticity of PEEK-OPTIMA of 3.6 GPa, which is similar to that of cortical bone. This specific stiffness encourages load sharing between implant material and natural bone, thereby stimulating bone healing activity. The material provides excellent strength and rigidity. PEEK-OPTIMA also exhibits high fatigue resistance and a low wear factor. Extensive investigations into the biocompatibility of PEEK- OPTIMA have proven that the material is suitable for the use as a long-term implant. The cranial side of the implant has an anatomical shape. A toothed surface offers primary stability to avoid migration in all directions (Fig.2). Fig. 1 Fig. 2 5

6 CeSpace Trail Implants Trial implants are available for all implant sizes and can be used to safely establish the appropriate implant selection. Due to the different shape of the implants we offer assorted trials for CeSpace Titanium and CeSpace PEEK. The trail implants are of paramount importance with regard to implant size determination. The height of the CeSpace Titanium trails corresponds exactly with the height of the final implant and is inclusive of the fixation crown. Titanium Due to the anatomical shape of the implant different CeSpace PEEK trials are necessary. Laser markings on the handle as well as trial itself indicate the cranial and caudal side of the trial. PEEK 6

7 CeSpace Inserter The Titanium implant is held securely and firmly onto the CeSpace inserter by means of a screw joint. The flexible sheath on the inserter has a stop at the front end which prevents the implant from being inserted too deeply in the intervertebral disc compartment. If required, the sheath can be rotated in any direction, to allow the position of the CeSpace implant to be checked and corrected during insertion. Titanium Due to the material properties of PEEK there is a chance of overwinding a thread. Thus the inserter for the PEEK implant has a clamp mechanism. The inserter is available with or without a safety feature, depending on the surgeons personal preference. The inserter without safety stop serves also as impactor. Two different pin sizes ensure the correct connection of implant and inserter. Thus the cranial side of the implant will always be on the cranial sid of the instrument as indicated via a laser marking. PEEK 7

8 Operating Technique 8

9 Patient Position The surgical procedure is performed under intubation anaesthesia. The patient is placed in the supine position with the head slightly reclined and resting in a head trough or ring. Support the lordotic cervical spine with a suitably sized polster, the thorax may be placed on a cushion to emphasise the reclination of the cervical spine (Fig. 1). The arms are fixed along the sides of the body. The image intensifier is positioned in such a way that fluoroscopy is possible in both the lateral and the frontal planes. Using the arm fixations, draw the shoulders down far enough to remove them from the radiation path of the segment to be fused. Fig. 1 Skin incision For a good cosmetic result, the skin incision should be made in a neck fold, which can be easily found by brief anteflexion of the head by the anaesthetist. Establish the correct height for the incision using an image converter. After disinfection and sterile draping, the skin opening is made along the fold line. Starting from the midline, use a 3 cm incision for monosegmental fusion and 4 cm incision for bisegmental fusion. Exposure of the intervertebral space Once the skin incision has been made, a retractor is applied (Fig. 2). The subcutaneous tissue is separated from the platysma cranially, caudally and medially, and the platysma is pushed apart following the direction of its fibres. The margins of the platysma can be held apart with the retractor or with two surgical forceps. Now the medial edge of the sternocleidomastoid muscle is located and prepared with the index finger in the connective tissue space over the ventral surface of the cervical spine and under lateralisation of the vascular nerve bundle and medialisation of the trachea, oesophagus and thyroid gland. It is common at this point to feel osteophytic growths on the ventral margin. Fig. 2 9

10 Operating Technique After the Langenbeck hooks have been inserted, the entral surface of the cervical spine, still covered by a thin prevertebral layer of connective tissue, is revealed. This layer can now be opened with either a short scissor cut or bipolar coagulation to a point where it can finally be widened and pushed away cranially and caudally using a blunt tamper. A wire is set under x-ray monitoring to mark the intervertebral disc space. Finally, insert two Caspar retractor valves, of suitable length, under the retracted margins of the long neck muscle. If a second retractor is to be used with valves set cranially and caudally, the skin incision and the whole access must be larger. Discectomy/Preparation of the implant bed After the retractors have been inserted, the distraction screws are placed in position and the Caspar distractor is applied following the technique described by Caspar (Fig. 3). Before distraction of the segment, the intervertebral disc should be completely incised and partially removed using the Cushing-Knife. This makes subsequent distraction easier. Complete clearance of the intervertebral disc space is achieved using various grasping forceps, curettes and sharp scoops (Fig. 4). A better view into the intervertebral disc space can be achieved by removing the annulus fibrosis in the furthest possible lateral direction. While using a high speed burr to remove the posterior rim and/or dorsal osteophytes, great care must be taken to avoid damaging the vertebral body endplates. If there is pronounced uncovertebral arthrosis, the dorsal section of the uncovertebral joint must also be removed. The cartilaginous layers of the endplates must be completely removed. It is important to note that excessive removal of the endplates may weaken the construct and cause subsidence of the CeSpace implant. As a general rule, whenever possible, always preserve the integrity of the vertebral body endplates. Fig. 3 Fig. 4 10

11 Operating Technique Implant Selection After full decompression of the nerve structures the correct implant size can be established using the trial implants (Fig. 5). CeSpace Insertion Once CeSpace is attached to the inserter, it can be introduced into the intervertebral space using image converter monitoring (Fig. 6). The stop at the distal end of the insertion instrument ensures the implant is not inserted too far into the intervertebral space. The implant should be inserted 1 to 2 mm beyond the anterior border of the vertebral bodies and centrally in A.P. (Fig. 7). Relaxing the Caspar distractor reactivates the ligament apparatus and produces a secure fit of CeSpace within the intervertebral disc space. Slight sidewards movement of the inserter will check whether the implant is stable and securely positioned. If CeSpace can be moved slightly in the intervertebral space, there is a risk of dislocation and the implant should be replaced with the next largest size in height. If satisfied with the implant location, remove the inserter. The correct position of the implant is documented by radiographic checks in two planes. After suitable haemostasis the wound can be closed with redondrainage. Fig. 5 CeSpace implants are indicated for the treatment of degenerative diseases of the cervical intervertebral disc and can be used for cervical fusion in the C3 to C7 region. Fig. 6 Fig. 7 11

12 Implant Diameter CeSpace Titanium Height Depth Angle The specified height for the lordotic implant refers to the average height, which means the anterior section of the implant is higher than the posterior section. Article No. Description Angle Height Diameter Depth FJ 134 T CeSpace cervical implant 5 4 mm 14 mm 11.5 mm FJ 135 T CeSpace cervical implant 5 5 mm 14 mm 11.5 mm FJ 136 T CeSpace cervical implant 5 6 mm 14 mm 11.5 mm FJ 137 T CeSpace cervical implant 5 7 mm 14 mm 11.5 mm FJ 144 T CeSpace cervical implant 5 4 mm 16 mm 13.5 mm FJ 145 T CeSpace cervical implant 5 5 mm 16 mm 13.5 mm FJ 146 T CeSpace cervical implant 5 6 mm 16 mm 13.5 mm FJ 147 T CeSpace cervical implant 5 7 mm 16 mm 13.5 mm All CeSpace implants are individually sterile packed. Implant materials ISOTAN F Titanium forged alloy (Ti6Al4V / ISO ) Plasmapore Pure titanium (Ti / ISO ) 12

13 Instrumentation Recommended sterile container JK / JN 410 P Recommended set configuration Article No. Description Handle colour Recommended FJ 164 R Trial implant, ø 14 x 4 mm blue 1 FJ 165 R Trial implant, ø 14 x 5 mm blue 1 FJ 166 R Trial implant, ø 14 x 6 mm blue 1 FJ 167 R Trial implant, ø 14 x 7 mm blue 1 FJ 174 R Trial implant, ø 16 x 4 mm green 1 FJ 175 R Trial implant, ø 16 x 5 mm green 1 FJ 176 R Trial implant, ø 16 x 6 mm green 1 FJ 177 R Trial implant, ø 16 x 7 mm green 1 FJ 100 R Inserter 1 FJ 171 R Perforated tray with holding and storage elements 1 CeSpace Titanium 13

14 Implant Diameter Depth CeSpace PEEK Height Angle Article No. Description Angle Height Diameter Depth FJ 404 P CeSpace PEEK implant 5 4 mm 14 mm 11.5 mm FJ 405 P CeSpace PEEK implant 5 5 mm 14 mm 11.5 mm FJ 406 P CeSpace PEEK implant 5 6 mm 14 mm 11.5 mm FJ 407 P CeSpace PEEK implant 5 7 mm 14 mm 11.5 mm FJ 408 P CeSpace PEEK implant 5 8 mm 14 mm 11.5 mm FJ 424 P CeSpace PEEK implant 5 4 mm 16 mm 13.5 mm FJ 425 P CeSpace PEEK implant 5 5 mm 16 mm 13.5 mm FJ 426 P CeSpace PEEK implant 5 6 mm 16 mm 13.5 mm FJ 427 P CeSpace PEEK implant 5 7 mm 16 mm 13.5 mm FJ 428 P CeSpace PEEK implant 5 8 mm 16 mm 13.5 mm All CeSpace implants are individually sterile packed. Implant materials PEEK-OPTIMA Registered Trademark of Invibio Ltd, Lancashire FY5 4QD, UK 14

15 Instrumentation Recommended set configuration Article No. Description Handle colour Recommended Optional FJ 384 R Trial implant 5, ø 14x4 mm anat. blue 1 FJ 385 R Trial implant 5, ø 14x5 mm anat. blue 1 FJ 386 R Trial implant 5, ø 14x6 mm anat. blue 1 FJ 387 R Trial implant 5, ø 14x7 mm anat. blue 1 FJ 388 R Trial implant 5, ø 14x8 mm anat. blue 1 FJ 394 R Trial implant 5, ø 16x4 mm anat. green 1 FJ 395 R Trial implant 5, ø 16x5 mm anat. green 1 FJ 396 R Trial implant 5, ø 16x6 mm anat. green 1 FJ 397 R Trial implant 5, ø 16x7 mm anat. green 1 FJ 398 R Trial implant 5, ø 16x8 mm anat. green 1 FJ 413 P CeSpace PEEK Packing Block 1 FF 914 R Caspar Tamper 5 mm 1 FJ 419 R Impactor 1 FJ 420 R Inserter CeSpace PEEK anat. 1 FJ 411 P CeSpace PEEK Tray 1 CeSpace PEEK 15

16 All rights reserved. Technical alterations are possible. This leaflet may be used for no other purposes than offering, buying and selling of our products. No part may be copied or reproduced in any form. In the case of misuse we retain the rights to recall our catalogues and pricelists and to take legal actions. Aesculap AG & Co. KG Am Aesculap-Platz Tuttlingen Phone Fax Brochure No. O /2/1