Anterior Lumbar Interbody Fusion (ALIF). Instrument set supports placement of ALIF spacers using anterior or anterolateral approach.

Transcription

1 Anterior Lumbar Interbody Fusion (ALIF). Instrument set supports placement of ALIF spacers using anterior or anterolateral approach. Technique Guide Instruments and implants approved by the AO Foundation

2 Table of Contents Introduction Anterior Lumbar Interbody Fusion (ALIF) 2 AO Principles 3 Surgical Technique Preoperative Planning 4 Straight Anterior Approach 6 Anterolateral Approach (45 Offset) 11 Product Information Instruments 13 Set List 16 Synthes Spine

3 Anterior Lumbar Interbody Fusion (ALIF) ALIF Instrument Set The ALIF Instrument Set supports the placement of ALIF Spacers using an anterior or anterolateral approach. Anterior Approach ALIF instruments can be used in an ALIF procedure using a straight anterior approach to the lumber spine. The illustration depicts an ALIF Spacer being implanted at the L5 S1 level. Anterolateral Approach The ALIF instruments can also be used in an ALIF procedure using an anterolateral approach, or 45 offset from straight anterior. This approach preserves the anterior longitudinal ligament and avoids patient vasculature. The illustration depicts an ALIF Spacer being implanted at the L4 L5 level. 2 Synthes Spine Anterior Lumbar Interbody Fusion (ALIF)

4 AO Principles In 1958, the AO ASIF (Association for the Study of Internal Fixation) formulated four basic principles, which have become the guidelines for internal fixation. 1 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 Principles as Applied to the Spine 3 Anatomical Alignment 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, 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, H. Willenegger: AO Manual of Internal Fixation, 3rd Edition. Berlin; Springer-Verlag Ibid. 3. M. Aebi, J.S. Thalgott, J.K. Webb. AO ASIF Principles in Spine Surgery. Berlin; Springer-Verlag Synthes Spine 3

5 Preoperative Planning 1 Determine surgical approach (anterior or anterolateral) The surgical approach, based on the surgeon s preference, determines the implant type. Anterior approach Anterolateral approach 4 Synthes Spine Anterior Lumbar Interbody Fusion (ALIF)

6 2 Determine implant height Instrument 8052 ALIF Preoperative Planner Overlay the ALIF Preoperative Planner on a lateral radiograph of the intervertebral discs to determine implant height. The implant must be seated firmly with a tight fit between endplates when the segment is fully distracted. It is essential to use the tallest possible implant to maximize stability. Due to variability in the degree of magnification, the templates are only an estimate and may not always provide an exact implant measurement. Templates represent 40% 80% (in 5% increments) and 100% actual size for use with MRI and CT scans. 10% and 15% magnification templates are available for x-ray use. Synthes Spine 5

7 Straight Anterior Approach As an adjunct to the ALIF surgical technique, the SynFrame Access and Retractor System may be used. The SynFrame allows direct visualization and stable retraction for less invasive spine surgery, eliminating the need for large, handheld retractors. 1 Expose the disc and prepare the endplate Instrument ALIF Rasp Expose the midline of the intervertebral disc to position the center of the implant on the vertebral midline. Remove enough disc and anterior longitudinal ligament for the spacer to fit properly. The ALIF Rasp assists in the removal of the superficial layers of the cartilaginous endplates. Note: Removing the superficial layers of the cartilaginous endplates exposes bleeding bone. Adequate preparation of the endplates is important to facilitate vascular supply to the bone graft. Excessive cleaning, however, may weaken the endplate due to removal of bone underlying the cartilaginous layers. 6 Synthes Spine Anterior Lumbar Interbody Fusion (ALIF)

8 2 Distract and size Instruments ALIF Trial Spacers, angled, lateral or anterior Curved Distractor Trial Spacer Handle, angled Distractor Trial Spacer Handle Distracting the segment is essential to restore disc height, open the neural foramen, and stabilize the implant. Distract the disc space using the Distractor with the appropriate Distractor Blades, or the Curved Distractor. Place the blades of the Distractor into the disc space. To ensure that the implant is inserted symmetrically in the disc space, align the Distractor Blades with the anterior midline of the vertebral bodies. Once the desired level of distraction is achieved, determine the implant size using the ALIF Trial Spacers. Select the anterior ALIF Trial Spacer that corresponds to the implant size determined during preoperative planning and thread it onto the Trial Spacer Handle or angled Trial Spacer Handle. Synthes Spine 7

9 Straight Anterior Approach continued 2 Distract and size continued Slide the anterior ALIF Trial Spacer through the Distractor Blades and into the disc space. If the chosen trial spacer is too small, use incrementally larger trial spacers until a tight fit is achieved. With the segment fully distracted, the ALIF Trial Spacer must fit tightly between the endplates to ensure that the disc height is not lost once the distractor is removed. It is essential to use the tallest possible implant (height) to maximize segment stability. Note: Ensure that the Distractor is held firmly in place while using the ALIF Trial Spacer. Select the implant corresponding to the correct trial spacer. Distraction can then be temporarily relaxed. 8 Synthes Spine Anterior Lumbar Interbody Fusion (ALIF)

10 3 Insert the implant Instruments Implant Holder, slot, angled Implant Holder, slot Install the implant using the Implant Holder or the angled Implant Holder, ensuring that the tallest side of the implant lies against the holder. The Implant Holder aligns with the preformed slots on the implant for easy insertion. Tighten the locking screw on the Implant Holder to firmly secure the instrument jaws against the implant. Pack bone graft material into the center of the ALIF implant. Distract the segment again and hold the distraction by tightening the locking screw on the Distractor handle. Introduce the implant into the exposed disc space between the Distractor Blades. The implant should be inserted as far as possible or until the Implant Holder contacts the Distractor Blades (at least 2/3 of implant depth). Synthes Spine 9

11 Straight Anterior Approach continued 3 Insert the implant continued Instruments Angled Impactor, crescent Impactor, crescent Release the Implant Holder by loosening the locking screw. Final seating of the implant is done with gentle blows of the crescent Impactor or Angled Impactor while maintaining the Distractor position. Important: Before use, ensure that the impactor fits flush against the implant. Do not forcibly strike the impactor when tapping the implant into position. Finally, loosen the locking screw on the Distractor handle, release distraction, and remove the Distractor. 10 Synthes Spine Anterior Lumbar Interbody Fusion (ALIF)

12 Anterolateral Approach (45 Offset) 1 Expose disc and prepare endplate For anterolateral insertion, the center of the implant will sit 45 offset to the anterior vertebral midline. Remove the disc and prepare the endplates according to Step 1 of the Straight Anterior Approach (see page 6). 2 Distract and size Instrument ALIF Trial Spacers, anterolateral Curved Distractor Distractor Trial Spacer Handle Distraction of the segment is essential to restore disc height, open the neural foramen, and stabilize the implant. Distract prior to insertion of the implant using the appropriate Distractor. Once the desired level of distraction is achieved, determine the correct implant size using the ALIF Trial Spacers. Select the anterolateral ALIF Trial Spacer that corresponds with the implant size determined during preoperative planning and thread it onto the Trial Spacer Handle. Insert the trial spacer and determine the correct implant height as described in Step 2 of the Straight Anterior Approach (see pages 7 8). Synthes Spine 11

13 Anterolateral Approach (45 Offset) continued 3 Insert the implant Insert the implant according to Step 3 of the Straight Anterior Approach (see page 9 10). 12 Synthes Spine Anterior Lumbar Interbody Fusion (ALIF)

14 Instruments ALIF Trial Spacers, angled, lateral or anterior mm mm mm mm mm mm mm ALIF Trial Spacers, anterolateral mm mm mm mm mm mm mm ALIF Sizer Handle Used with the ALIF Sizers ALIF Sizers, detachable mm mm mm mm mm mm mm ALIF Rasp Optimizes cleaning and preparation of the endplates Cutting surface designed to quickly remove tissue without being overly aggressive Synthes Spine 13

15 Instruments continued Curved Distractor Profile clears patient vasculature Fixed-blade design Trial Spacer Handle, angled Connects with the ALIF Trial Spacers to size implant Detaches easily from the Trial Spacer intraoperatively Angled Impactor, crescent Seats the ALIF Spacer in the disc space Designed with textured contact area to prevent slipping during impaction Curved, two-point contact area helps distribute impaction forces Angled tip simplifies access to L5 S1 by accommodating patient anatomy Implant Holder, slot, angled Serrated surface of jaws securely grips the ALIF Spacer during insertion Angled tip gains easier access to L5 S1 by accommodating patient anatomy Implant Holder, slot Serrated surface of jaws securely grips the ALIF Spacer during insertion Distractor Multiple blade options angled and straight Accommodates varied length blades to address patient anatomy and access, including an angled approach to L5 S1 14 Synthes Spine Anterior Lumbar Interbody Fusion (ALIF)

16 Distractor Blades mm, right mm, left mm, right mm, left mm, right mm, left angled, right angled, left mm, left , mm, right 40 mm 45 mm 50 mm 55 mm Impactor, crescent Seats the ALIF Spacer in the disc space Designed with textured contact area to prevent slipping during impaction Curved, two-point contact area helps distribute impaction forces Trial Spacer Handle Connects with the ALIF Trial Spacers to size implant Detaches easily from the Trial Spacer intraoperatively 8052 ALIF Preoperative Planner Synthes Spine 15

17 ALIF Instrument Set ( ) Graphic Case ALIF Graphic Case Instruments ALIF Sizer Handle ALIF Graft Packing Block ALIF Rasp Graft Packer Curved Distractor Trial Spacer Handle, angled Angled Impactor, crescent Implant Holder, slot, angled Implant Holder, slot Distractor Impactor, crescent Trial Spacer Handle, 2 ea ALIF Preoperative Planner ALIF Trial Spacers, angled, lateral or anterior mm mm mm mm mm mm mm ALIF Trial Spacers, anterolateral mm mm mm mm mm mm mm ALIF Sizers, detachable mm mm mm mm mm mm mm Distractor Blades mm, right mm, left mm, right mm, left mm, right mm, left angled, right angled, left mm, left mm, right Also Available Anterior Instrument Set SynFrame Standard Access System SynFrame Anterior Lumbar Spine System 16 Synthes Spine Anterior Lumbar Interbody Fusion (ALIF)

18 Synthes Spine 1302 Wrights Lane East West Chester, PA Telephone: (610) To order: (800) Fax: (610) Synthes, Inc. or its affiliates. All rights reserved. Synthes is a trademark of Synthes, Inc. or its affiliates. Printed in U.S.A. 3/07 J3544-C