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

Anterior Lumbar Interbody Fusion

(ALIF).

Instrument set supports

placement of ALIF spacers using anterior

or anterolateral approach.

Introduction

Surgical Technique

Product Information

Table of Contents

Anterior Lumbar Interbody Fusion (ALIF) 2

AO Principles 3

Preoperative Planning 4

Straight Anterior Approach 6 Anterolateral Approach (45° Offset) 11

Instruments 13

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 antero-lateral approach, or 45° offset from straight anterior. This approach preserves the anterior longitudinal ligament and avoids patient vascula-ture. The illustration depicts an ALIF Spacer being implanted at the L4–L5 level.

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 Spine3

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. 1991.

2. Ibid.

3. M. Aebi, J.S. Thalgott, J.K. Webb. AO ASIF Principles in Spine Surgery. Berlin; Springer-Verlag. 1998.

Preoperative Planning

1

Determine surgical approach (anterior or anterolateral)

The surgical approach, based on the surgeon’s preference, determines the implant type.

2

Determine implant height Instrument

8052 ALIF Preoperative Planner Overlay the ALIF Preoperative Planner on a lateral radiograph of the interverte-bral 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.

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

389.156 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.

2

Distract and size Instruments

389.060 – ALIF Trial Spacers, angled, lateral or anterior 389.066

396.941 Curved Distractor

396.957 Trial Spacer Handle, angled 397.012 Distractor

397.089 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.

Straight Anterior Approach

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.

3

Insert the implant Instruments

396.959 Implant Holder, slot, angled 397.011 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).

Straight Anterior Approach

3

Insert the implant continued

Instruments

396.958 Angled Impactor, crescent 397.023 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.

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

389.143– ALIF Trial Spacers, anterolateral 389.149

396.941 Curved Distractor 397.012 Distractor

397.089 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).

Anterolateral Approach (45° Offset)

3

Insert the implant

Insert the implant according to Step 3 of the Straight Anterior Approach (see page 9–10).

Instruments

389.150 ALIF Sizer Handle Used with the ALIF Sizers

389.156 ALIF Rasp

– Optimizes cleaning and preparation of the endplates

– Cutting surface designed to quickly remove tissue without being overly aggressive ALIF Sizers, detachable

389.159 9 mm 389.161 11 mm 389.163 13 mm 389.165 15 mm 389.167 17 mm 389.169 19 mm 389.171 21 mm

ALIF Trial Spacers, angled, lateral or anterior 389.060 9 mm 389.061 11 mm 389.062 13 mm 389.063 15 mm 389.064 17 mm 389.065 19 mm 389.066 21 mm

ALIF Trial Spacers, anterolateral 389.143 9 mm 389.144 11 mm 389.145 13 mm 389.146 15 mm 389.147 17 mm 389.148 19 mm 389.149 21 mm

397.012 Distractor

– Multiple blade options—angled and straight

Instruments

396.958 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 396.959 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

397.011 Implant Holder, slot

Serrated surface of jaws securely grips the ALIF Spacer during insertion

396.957 Trial Spacer Handle, angled

– Connects with the ALIF Trial Spacers to size implant

– Detaches easily from the Trial Spacer intraoperatively

396.941 Curved Distractor

– Profile clears patient vasculature – Fixed-blade design

Distractor Blades 396.944 45 mm, right 396.945 45 mm, left 396.946 50 mm, right 396.947 50 mm, left 396.948 55 mm, right 396.949 55 mm, left 396.952 angled, right 396.953 angled, left 397.013 40 mm, left 397.014 40 mm, right _{40 mm 45 mm 50 mm 55 mm} 397.013 396.944 396.946 396.948 397.014 396.945 396.947 396.949 396.952, 396.953 397.023 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

8052 ALIF Preoperative Planner 397.089 Trial Spacer Handle

– Connects with the ALIF Trial Spacers to size implant

– Detaches easily from the Trial Spacer intraoperatively

Graphic Case

690.031 ALIF Graphic Case

Instruments

389.150 ALIF Sizer Handle 389.155 ALIF Graft Packing Block 389.156 ALIF Rasp

394.578 Graft Packer 396.941 Curved Distractor

396.957 Trial Spacer Handle, angled 396.958 Angled Impactor, crescent 396.959 Implant Holder, slot, angled 397.011 Implant Holder, slot 397.012 Distractor

397.023 Impactor, crescent 397.089 Trial Spacer Handle, 2 ea. 8052 ALIF Preoperative Planner ALIF Trial Spacers, angled, lateral or anterior 389.060 9 mm 389.061 11 mm 389.062 13 mm 389.063 15 mm 389.064 17 mm 389.065 19 mm 389.066 21 mm ALIF Trial Spacers, anterolateral 389.143 9 mm 389.144 11 mm 389.145 13 mm 389.146 15 mm 389.147 17 mm 389.148 19 mm 389.149 21 mm ALIF Sizers, detachable 389.159 9 mm 389.161 11 mm Distractor Blades 396.944 45 mm, right 396.945 45 mm, left 396.946 50 mm, right 396.947 50 mm, left 396.948 55 mm, right 396.949 55 mm, left 396.952 angled, right 396.953 angled, left 397.013 40 mm, left 397.014 40 mm, right Also Available

105.939 Anterior Instrument Set

187.310 SynFrame Standard Access System 187.316 SynFrame Anterior Lumbar Spine System

Synthes Spine 1302 Wrights Lane East West Chester, PA 19380 Telephone: (610) 719-5000 To order: (800) 523-0322