Atlas of Minimal Access
`Spine Surgery
`
`SECOND EDITION
`
`EDITED BY
`
`John J. Regan, M.D.
`Medical Director, Cedars-Sinai Institute for Spinal Disorders,
`Cedars-Sinai Medical Center, Los Angeles, California
`
`Isador H. Lieberman, B.Sc., M.D., M.B.A., F.R.C.S.(C)
`Orthopaedic and Spinal Surgeon, Cleveland Clinic Spine Institute,
`Departments of Orthopaedics and Neurosurgery, The Cleveland Clinic
`Foundation, Cleveland, Ohio
`
`ILLUSTRATORS
`Alexandra Baker, M.s., C.M. l., and David L. Baker, M.A.
`
`Quality Medical Publishing, Inc.
`
`ST. LOUIS, MISSOUR I
`
`2004
`
`

`
`Copyright © 2004 by Quality Medical Publishing, Inc.
`
`All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted
`in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior
`permission of the publisher.
`
`Previous edition copyrighted 1995
`
`Printed in China
`
`This book presents current scientific information and opinion pertinent to medical professionals. It does not
`provide advice concerning specific diagnosis and treatment of individual cases and is not intended for use by
`the layperson. Medical knowledge is constantly changing. As new information becomes available, changes in
`treatment, procedures, equipment, and the use of drugs becomes necessary. The editors/authors/contributors
`and the publisher have, as far as it is possible, taken care to ensure that the information given in this text is
`accurate and up to date. However, readers are strongly advised to confirm that the information, especially with
`regard to drug usage, complies with the latest legislation and standards of practice. The authors and publisher
`will not be responsible for any errors or liable for actions taken as a result of information or opinions expressed
`in this book.
`
`The publishers have made every effort to trace the copyright holders for borrowed material. If they have
`inadvertently overlooked any, they will be pleased to make the necessary arrangements at the first opportunity.
`
`PUBLISHER Karen Berger
`PROJECT MANAGER Caroli ta Deter, Donna Rothenberg
`ASSOCIATE EDITOR Michelle Berger
`PRODUCTION Carolyn Reich, Susan Trail
`COVER DESIGN David Berger
`
`Quality Medical Publishing, Inc.
`11970 Borman Drive, Suite 222
`St. Louis, Missouri 63146
`Telephone: 1-800-348-7808
`Web site: http://www.qmp.com
`
`LIBRARY OF CONGRESS CATALOGING -IN -PUBLICATION DATA
`
`Atlas of minimal access spine surgery I edited by John J. Regan, Isador Lieberman.-2nd ed.
`p.
`; cm.
`Rev. ed. of: Atlas of endoscopic spine surgery I edited by John J. Regan,
`Paul C. McAfee, Michael J. Mack. 1995.
`Includes bibliographical references and index.
`ISBN 1-57626- 100-X (hardcover)
`1. Spine-Endoscopic surgery. 2. Spine-Endoscopic surgery-Atlases.
`[DNLM: l. Spine-surgery-Atlases. 2. Endoscopy-methods-Atlases. 3. Spinal Diseases(cid:173)
`surgery-Atlases. 4. Surgical Procedures, Minimally Invasive-methods-Atlases. WE 17
`I. Regan, John)., 1952-
`M6648 2001]
`II. Lieberman, I.H. (Isador H. )
`III. Regan, John J., 1952-
`Atlas of endoscopic spine surgery.
`RD533 .R44 2002
`617.5'6059-dc21
`20020 10305
`
`QM/EB/EB
`5 4 3 2
`
`

`
`Contents
`
`Part I. BASICS
`
`Part II. DECISION MAKING
`
`1 Collaborative Surgery 3
`Ronald f. Aronoff, M.D.
`
`8 Lumbar Spine 99
`john f. Regan, M.D.
`
`2 Anatomic Considerations 5
`
`Thoracoscopic Anatomy of the Spine 5
`Anthony D. McBride, M.D.
`
`Laparoscopic Anatomy of the Lumbar Spine 15
`Larry M. Parker, M.D.
`
`3 Equipment and Instrumentation for Endoscopic
`Spine Surgery 29
`john f. Regan, M.D., and Alan T. Villavicencio, M.D.
`
`4 Endoscopic Approach Strategies 43
`John f. Regan, M.D., and Alan T. Villavicencio, M.D.
`
`5 Training and Credentialing 63
`David S. Thoman, M.D., and Edward H. Phillips, M.D.
`
`6 Complications 67
`Paul C. McAfee, M.D., and fed S. Vanichkachorn, M.D.
`
`7 Anesthetic Issues 87
`Isador H. Lieberman, B.Sc., Al.D., MB.A., F.R.C.S.(C),
`Leo11ardo f. Lozada, Al.D., Micha el f. Mack, M.D.,
`a11d Ronald f. Aronoff, M D.
`
`9 Thoracic Spine 103
`Neel Anand, M.D., Meli.Orth., and John f. Regan, M.D.
`
`10 Spinal Deformity 115
`
`Adolescent Spinal Deformity 115
`Lawrence G. Lenke, M.D.
`
`Adult Spinal Deformity 122
`Isador H. Lieberman, B.Sc., M.D., M.B.A., F.R.C.S. (C)
`
`Part III. SURGICAL TECHNIQUES
`
`Lumbar Spine
`
`11 Laparoscopic Discectomy and
`Fusion (LS-Sl) 131
`fames H. Maxwell, M.D., Dimitri us E.M. Litwin, M.D.,
`john f. Regan, M.D., and john R. Romanelli, M.D.
`
`12 Laparoscopic Fusion of the Lumbar
`Spine (L4-5)
`161
`]oh11 ]. Regan, M.D., a11d Ronald f. Aronoff, MD.
`
`xv
`
`

`
`xvi
`
`Contents
`
`13 Laparoscopic Lateral L4-5 Disc Exposure 183
`Fred Brody, M.D., and Isador H. Lieberman, B.Sc., M.D., M.B.A.,
`F.R.C.S.(C)
`
`14 Lateral Retroperitone~ Approach to the
`Lumbar Spine: The Lateral Bagby and Kuslich
`Procedure (Tl2-L5) 189
`Paul C. McAfee, M.D.
`
`15 Gasless Endoscopic Lumbar Surgery:
`Balloon-Assisted Retroperitoneal Approach to the
`Anterior Lumbar Spine 205
`John S. Thalgott, M.D., and James M. Giuffre, B.A.
`
`16 Microsurgical Techniques in Lumbar Spinal
`Stenosis 221
`K. Daniel Riew, M.D. , and John M. Rhee, M.D.
`
`Thoracic Spine
`
`17 Treatment of Thoracic Disc Disease 235
`Curtis A. Dickman, M.D.
`
`18 Endoscopic Anterior Repair in Spinal Trauma 285
`Rudolf Beisse, M.D.
`
`Section on Surgical Technique for Reconstruction of
`Spinal Tumors 310
`Michael Potulski, M.D., Daniel H. Kim, M.D., and
`Tae-Ahn Jahng, M.D., Ph.D.
`
`19 Thoracoscopic Sympathectomy 321
`Curtis A. Dickman, M.D.
`
`Spinal Deformity
`
`20 Pediatric Spinal Deformities 341
`Alvin H. Crawford, M.D. , and Atiq Durrani, M.D.
`
`21 Alternative Approaches to Thoracoscopic
`Anterior Spinal Release and Fusion for Spinal
`Deformity 385
`Peter 0. Newton, M.D.
`
`22 Prone-Position Endoscopic Approach for Deformity
`Surgery 399
`Isador H. Lieberman, B.Sc., M.D., M.B.A ., F.R.C.S. (C)
`
`23 Anterior Spinal Instrumentation in Spinal
`Deformity 409
`
`Thoracoscopic Anterior Release and Fusion Using
`MOSS-Miami Instrumentation 409
`Randal R. Betz, M.D., Peter 0. Newton, M.D., David H.
`Clements III, M.D., and Rohinton K. Balsara, M.D., F.A.C.C.P.
`
`Endoscopic Techniques for Treatment of Thoracic and
`Thoracolumbar Scoliosis 423
`George D. Picetti III, M.D., Janos P. Ertl, M.D. , and
`H. Ulrich Bueff, M.D.
`
`Part IV. NEW TECHNOLOGY
`
`24 Minimally Invasive Vertebral Body Augmentation
`and Reconstruction for Osteoporotic and Osteolytic
`Wedge Compression Fractures 441
`Isador H. Lieberman, B.Sc., M.D., M.B.A., F.R. C.S.(C), and
`Mark A. Reiley, M.D.
`
`25
`
`Intradiscal Electrothermal Therapy 451
`Jeffrey A. Saal, M.D., and Joel S. Saal, M.D.
`
`26 Microendoscopic Discectomy 465
`Robert E. Isaacs, M.D., Faheem A. Sandhu, M.D., Ph.D.,
`and Richard G. Fessler, M.D., Ph.D.
`
`27 Percutaneous Discectomy 487
`Anthony T. Yeung, M.D.
`
`28 Nucleus Pulposus Replacement 517
`Qi-Bin Bao, Ph.D., and Hansen A. Yuan, M.D.
`
`29 Link SB Charite Total Disc Replacement 525
`Paul C. McAfee, M.D.
`
`30 Extreme Lateral Interbody Fusion (XLIF) 539
`Marc I. Ma/berg, M.D.
`
`Index 555
`
`

`
`Extreme Lateral Interbody Fusion
`(XLIF)
`
`Marc I. Malberg, M.D.
`
`Lumbar and lumbosacral fusion is commonly performed for intractable back pain and/or
`instability. 1·2 An evolution of technique since the first lumbar fusion in 1911 has resulted in
`improvement in the rate of fusion, hospital stay, and morbidity. However, lumbar fusion is
`still a major procedure, which can result in considerable postoperative pain and prolonged
`recovery. Techniques designed to improve fusion rates, such as transpedicular screws and
`circumferential fusions, potentially add to the morbidity. Minimally invasive and endo(cid:173)
`scopic approaches attempt to reduce morbidity without compromising long-term out(cid:173)
`comes.
`Attempts to reduce surgical dissection from a posterior approach suffer from the limit(cid:173)
`ed exposure of bone surface for a posterolateral fusion mass. Posterior lumbar interbody
`fusion (P LIF) minimizes muscle dissection but exposes the cauda equina to scar and possi(cid:173)
`ble injury. 3·5 Anterior and laparoscopic interbody fusion (ALIF) exposes the viscera and
`retroperitoneal vessels to injury4·6· 10 and frequently requires another surgeon specialist. In
`addition, controversy remains as to whether an anterior cage is adequate as a stand-alone
`procedure. 11 -14 If supplemental posterior support proves advisable, then the advantage of
`the laparoscopic approach fades.
`Access to the lumbar disc spaces through a lateral approach has, until recently, been in(cid:173)
`frequently employed for fusion procedures. 15-18 When it is performed, it is often by a lateral
`retroperitoneal technique, which, like laparoscopic surgery, also frequently requires a second
`surgeon for exposure. Renewed interest in a posterolateral or far-lateral approach may have
`resulted from the success reported from intradiscal procedures for nerve root decompres(cid:173)
`sion.19-21
`Posterolateral disc procedures typicall y access the disc near the foramen through
`Kambin's triangle.19 The low complication rate of these disc procedures is attributable to
`the diminutive size of the endoscopes used for discectomy. Larger scopes or cannulas in-
`
`539
`
`

`
`540
`
`NEW TECHNOLOGY
`
`crease the exposure to injury to the neural elements. Kam(cid:173)
`bin's triangle is not an adequately sized space within which
`to accomplish an interbody fusion. There is adequate space,
`however, anterior to the nerve root but posterior to the
`-23 Disc procedures here at the lateral
`sympathetic chain. 22
`aspect of the spine access the'<!isc space through the psoas
`muscle. 1s-is,z4,25 This is an attractive approach but limited by
`the potential risk to the exiting nerve roots and lumbar
`plexus, which lie within the muscle itself.
`An extreme lateral interbody fusion (XLIF) through a
`minimally invasive incision and psoas muscle-splitting ap(cid:173)
`proach has the potential to significantly reduce the morbid(cid:173)
`ity currently associated with an interbody fusion of lumbar
`vertebrae. Performed with the patient in the prone position,
`the procedure can easily be supplemented with percuta(cid:173)
`neous insertion of transfacet screws, achieving the stable
`construct of interbody fusion with a posterior tension
`band.12-14,26-30
`The extreme lateral approach to the disc and the trans(cid:173)
`facet screw placement are achieved using a novel guide(cid:173)
`frame that allows reliable access to and maintenance of the
`target area. Seminal to this trans-psoas approach is a neuro(cid:173)
`monitoring system that is surgeon controlled and provides
`information about both direction and proximity of nerves
`at risk.
`Clinical experience with this minimally invasive fusion
`technique is limited. However, the early experience is en(cid:173)
`couraging. The quantitative abilities of the neuro-monitor(cid:173)
`ing system have been confirmed both clinically31 -32 and with
`intraoperative correlation with somatosensory-evoked po(cid:173)
`tentials. The guideframe is radiolucent with the exception
`of radiodense targeting elements and has been able to
`maintain access throughout the procedure with only slight
`readjustments.
`
`INDICATIONS AND CONTRAINDICATIONS
`The indications for this approach are the same as those al(cid:173)
`ready commonly used for a primary interbody fusion.
`These include discogenic pain, degenerative disc disease, de(cid:173)
`generative listhesis, and facet degeneration unresponsive to
`nonoperative management for a minimum of 3 months.
`Instability on flexion/extension radiographs without a pars
`defect should also be considered an indication. Upper lum(cid:173)
`bar segments can be accessed if the ribs do not interfere lat(cid:173)
`erally; the L2-3 disc has been successfully fused using this
`technique.
`Patients with a history of infection or suspicion of ma(cid:173)
`lignancy are not candidates for this procedure. Endplate
`erosion precludes adequate support for the interbody allo-
`
`graft. A bulging annulus is the natural consequence of de(cid:173)
`generation of the nucleus pulposus and does not represent
`a contraindication; however, an extruded or sequestered
`disc cannot be adequately treated by fusion alone. And pos(cid:173)
`terior access for direct decompression or disc fragment re(cid:173)
`moval, for example, is unattainable from this extreme later(cid:173)
`al approach.
`
`PREOPERATIVE PLANNING
`As with any major procedure, adequate medical evaluation
`is mandatory. Patients being considered for this approach
`should have a complete evaluation of the lumbar spine.
`Plain x-ray films should include lateral flexion/extension
`views. A fully exposed anteroposterior and lateral lumbar x(cid:173)
`ray film is necessary to evaluate the proximity of the ribs
`when considering fusion of the upper lumbar levels. An up(cid:173)
`to-date MRI and electrodiagnostic analysis complete the
`spinal studies. The history and physical examination must
`correlate with the studies and indicate that the disc(s) in
`question is indeed the pain generator.
`The plain x-ray films are evaluated to ensure that access
`is adequate. The entry point is approximately 14 cm lateral
`to the midline. The crest of the iliac wing may have to be
`drilled or osteotomized for the lower two segments. A tra(cid:173)
`versing rib can be gently retracted by the dilating cannulas
`if it is not completely overlying the interspace.
`Blood loss is minimal and transfusion has not been nec(cid:173)
`essary for this procedure. Conversion to an open procedure
`has not occurred to date. However, the preoperative discus(cid:173)
`sion with the patient should include consideration that the
`approach may not be feasible for technical reasons and that
`a decision may be made whether to convert to an open pro(cid:173)
`cedure or to abort the surgery.
`The operating room must be equipped with a canti(cid:173)
`levered, radiolucent table and radiolucent spinal frame.
`An image intensifier is required throughout the procedure.
`The neuro-monitoring system is placed on a mobile stand
`within the line of sight of the surgeon (Fig. 30-1 ). The sum
`of this equipment occupies considerable space, and there(cid:173)
`fore an adequately sized operating room should be sched(cid:173)
`uled in advance. The scrub team should have sufficient
`training in the use of the targeting device as well as the in(cid:173)
`struments.
`
`TECHNIQUE
`Patient Positioning
`After induction of general endotracheal tube anesthesia,
`surface EMG electrodes are placed on the myotomes corre(cid:173)
`sponding to the operative level(s). The electrodes are con-
`
`

`
`Extreme Lateral lnterbody Fusion (XLIF)
`
`541
`
`Anesthesiologist
`
`Fluoro(cid:173)
`scope
`
`FIGURE 30-1
`
`nected to the NeuroVision JJB system (NuVasive Inc., San
`Diego, Calif.) harness and routed to the monitor. Imped(cid:173)
`ance testing of the electrodes is carried out prior to posi(cid:173)
`tioning the patient on the table. The patient is then careful(cid:173)
`ly turned to th e prone position on the operating table and
`patient-positioning frame, and all pressure points are care(cid:173)
`fully padded. Draping must allow for a lateral approach
`mindful that the entry for the guidewire and dilating can(cid:173)
`nulas centers approximately 14 cm from the midline.
`
`Targeting
`AC-arm fluoroscope is used for imaging of the target area
`and the approach. A radiodense reticle is attached to the C(cid:173)
`a rm prior to sterile draping. The Hemi-Arc polar guide(cid:173)
`fram e (N uVasive Inc. ) is assembled on the ster ile table and
`affixed to the ipsilateral side rail of th e operating table (Fig.
`30-2, A).
`
`FIGURE 30-2
`
`

`
`542
`
`NEW TECHNOLOGY
`
`The C-arm is first oriented in the anteroposterior plane.
`The horizontal lines of the reticle crosshair displayed on the
`image are aligned parallel to the end plates of the target disc
`by adjusting the position of the C-arm. The vertical line of
`the reticle crosshair is adjusted to be at the lateral border of
`th e vertebrae (Fig. 30-2, B).· The Hemi-Arc is then posi(cid:173)
`tioned to superimpose its radiodense marker with the reti (cid:173)
`cle (Fig. 30-2, C).
`
`The C-arm is rotated to the lateral position and the ret(cid:173)
`icle crosshairs positioned parallel to the disc space (Fig. 30-·
`2, D). The Hemi-Arc is adjusted to align its marker withir.
`the C-arm reticle. The Hemi-Arc marker, when viewed ra(cid:173)
`diographically in the lateral position, has a target that con(cid:173)
`tains a center pin, which, when perfectly aligned, will appear
`as a radiodense circle (Fig. 30-2, E). At this point the Hemi(cid:173)
`Arc is correctly aligned in both the anteroposterior and lat(cid:173)
`eral planes.
`
`FIGURE 30-2 , cont'd
`
`

`
`Extreme Lateral lnterbody Fusion (XLIF)
`
`543
`
`Incision
`A skin guide is attached to the Hemi(cid:173)
`Arc, the curvature of which is calibrated
`in degrees from the midline. The skin
`guide is placed at the desireq entry point
`at approximately 65 degrees (Fig. 30-3).
`The initial cannulated dilator is placed
`at the skin through the skin guide to
`determine the midpoint of the incision.
`A 4 cm vertical incision is carried down
`through the subcutaneous tissue.
`
`FIGURE 30-3
`
`

`
`A
`
`544
`
`NEW TECHNOLOGY
`
`Tissue Dilation With
`Neurophysiologic Monitoring
`The initial dilator is advanced to the fas(cid:173)
`cia. An insulated guidewire with an ex(cid:173)
`posed beveled surface for stimulating is
`placed through the cannula of the dila(cid:173)
`tor. The guidewire is connected to the
`stimulator and then advanced toward
`the target disc space (Fig 30-4, A and B).
`The guidewire is stimulated as it is ad(cid:173)
`vanced to ensure a safe trajectory.
`Fluoroscopic image views confirm its
`position at the annulus (Fig. 30-4, C).
`Once safely positioned at the target, the
`guidewire is advanced through the
`annulus and serves to maintain the
`trajectory for the sequential dilators
`(Fig. 30-4, D).
`
`FIGURE 30-4
`
`

`
`Extreme Lateral lnterbody Fusion (XLIF)
`
`545
`
`The bushing of the skin guide is
`removed. Tissue dilation proceeds by
`passing sequential dilators over the ini(cid:173)
`tial dilator (Fig 30-4, E). Each dilator is
`insulated and has an expose,_d point at
`the distal end, which serves as the stimu(cid:173)
`lator. The radial position of the stimula(cid:173)
`tor corresponds to a notch at the proxi(cid:173)
`mal end. Each dilating cannula can be
`stimulated by means of a detachable
`connector at the proximal end leading
`to the neuro-monitor. Each dilator can
`be rotated as it is advanced through the
`psoas muscle. The cannula is stimulated
`in any direction and as often as indicated
`for accurate monitoring of proximity
`and location of nerves or nerve roots at
`risk. The NeuroVision JJB system pro(cid:173)
`vides surgeon-controlled stimulation
`(Fig. 30-4, F) and visual feedback
`(Fig. 30-4, G).
`
`G
`
`Vast:us Med/elis
`Femoral Nerve
`L2 L3 L4
`
`FIGURE 30-4 , cont'd
`
`

`
`H
`
`546
`
`NEW TECHNOLOGY
`
`Dilation continues until an operative
`corridor of 20 to 23 mm is achieved.
`The length of the final working cannula
`is determined by depth markings on
`the final dilating cannula (Fig. 30-4, H).
`The working cannula is now firmly af(cid:173)
`fixed to the skin guide. The sequential
`dilating cannulas are removed. A ball
`probe stimulator can be used through
`this access to check the perimeter of the
`working cannula for neural elements.
`Nerves traversing the operative field can
`be retracted under direct visualization.
`A safe, secure operating corridor is thus
`achieved (Fig 30-4, I and f).
`
`Discectomy
`An annulotomy is performed using
`a long-handled scalpel or disc cutter.
`A complete discectomy is performed
`using conventional instruments modi(cid:173)
`fied only for length. The position of the
`instruments can be monitored by imag(cid:173)
`ing to avoid penetrating the contralateral
`or anterior annulus. Elongated curettes
`and rasps complete the preparation
`of the endplates.
`
`FIGURE 30-4 , cont'd
`
`

`
`Extreme Lateral Interbody Fusion (XLIF)
`
`547
`
`Disc Space Distraction
`The appropriate graft size is determined
`by inserting smooth, radiodense sizers.
`The sizing instruments are rectangular
`in shape to allow ease of in..sertion paral(cid:173)
`lel to the disc space (Fig. 30-5, A). The
`disc height is sized by rotating the in(cid:173)
`strument 90 degrees within the disc
`space (Fig. 30-5, B), thereby distracting
`the disc and creating ligamentotaxis
`of the annulus. The sizers are inserted
`sequentially until the desired tension
`of the annulus is achieved. The corre(cid:173)
`sponding size broach can be impacted
`into the disc space to decorticate the
`endplates (Fig. 30-5, C), completing
`graft-site preparation.
`
`FIGURE 30-5
`
`

`
`548
`
`NEW TECHNOLOGY
`
`Allograft Insertion
`The Triad uniportal cortical bone allo(cid:173)
`graft (NuVasive Inc.) can be used as an
`interbody spacer, although the size of
`the working cannulas can accommodate
`various implant systems if desired. The
`Triad grafts have a semilunar footprint
`and varying height selections. The graft
`is affixed to an inserter instrument,
`which has two tines that slide into cor(cid:173)
`responding grooves in the allograft.
`Prior to insertion, demineralized bone
`matrix or other osteogenic material is
`packed into the medullary notch of the
`allograft (Fig. 30-6, A). The implant is
`impacted into the disc space and its po(cid:173)
`sition confirmed on image views prior
`to release of the inserter. The tines aid
`in visualization of the implant position
`on the images (Fig. 30-6, B). Additional
`demineralized bone matrix is packed
`around the implant. The working can(cid:173)
`nula is then removed and the psoas mus(cid:173)
`cle reapproximates itself. Standard clos(cid:173)
`ing procedures for the subcutaneous
`tissues and skin are followed.
`
`FIGURE 30-6
`
`

`
`Facet Screw Fixation
`The alignment crosshair is reattached
`to the Hemi-Arc and a cannula guide
`bracket is attached superiorly. Once
`again, the reticle on the C-arm is adjust(cid:173)
`ed parallel to the disc on the antero(cid:173)
`posterior view but at the disc space su(cid:173)
`perior to the implanted level. A radio(cid:173)
`dense marker on the Hemi-Arc extends
`distally on a plane parallel with the
`patient's midline. This marker is aligned
`with the starting point for the facet
`screw just superior and medial to the
`inferior articulating process of the supe(cid:173)
`rior vertebra (Fig. 30-7, A). On the later(cid:173)
`al view the Hemi -Arc is then rotated on
`its short axis until its radiodense marker
`is aligned with the starting point on the
`lateral view. Radiographically the start(cid:173)
`ing point usually coincides posteriorly
`with the plane of the superior endplate.
`The angle of the cannula guide is adjust(cid:173)
`ed to a trajectory that traverses the facet
`joint from superior-medial to inferior(cid:173)
`lateral and anchors in the pedicle (Fig.
`30-7, Band C). A single midline skin
`incision of 2.5 cm will allow placement
`of both the left and right screws. The
`incision is carried down to the fascia.
`
`Extreme Lateral lnterbody Fusion (XLIF)
`
`549
`
`FIGURE 30-7
`
`

`
`550
`
`EW TECHNOLOGY
`
`The guide bracket on the Hemi-Arc
`accommodates a trocar and cannula
`through which a guidewire is placed.
`The trocar and guidewire are advanced
`to bone under image control in both
`planes. The cannula is then advanced
`over the trocar to the bone and secured
`in the bracket. The guidewire is removed
`and the course of the screw is drilled
`under image control (Fig. 30-7, D to F) .
`
`FIGURE 30-7, cont'd
`
`

`
`Extreme Lateral lnterbody Fusion (XLIF)
`
`551
`
`The drill -trocar unit is calibrated to
`determine the appropriate length o f the
`4.5 mm diameter facet screw used. The
`contralateral screw is inserted throu gh
`the same incision in the same manner.
`Implant placement is then complete
`(Fig. 30-7, G to T).
`
`FIGURE 30-7, cont'd
`
`

`
`552
`
`NEW TECHNOLOGY
`
`POSTOPERATIVE CARE
`The patient is allowed out of bed as soon as comfort allows.
`Lumbar support is not necessary but can be used to speed
`mobilization. Oral analgesics generally suffice. Patients are
`discharged the following morning. They are instructed to
`resume activities of daily living. Physical therapy is not re(cid:173)
`quired, but the patient is instructed to avoid any strenuous
`activity. The initial follow-up visit is at 10 days to 2 weeks
`and then at intervals routinely used to follow an interbody
`fusion.
`
`COMPLICATIONS
`Experience with this procedure is limited and short term to
`date. Long-term complications, therefore, cannot be as(cid:173)
`sessed. The first two patients experienced sensory changes
`on the ipsilateral side during the lateral approach, which re(cid:173)
`solved spontaneously. In both cases the symptoms were not
`immediate, occurring 12 and 6 hours postoperatively. On
`careful examination of the distribution of the numbness, it
`was thought that the source was irritation of the genito(cid:173)
`femoral or ilioinguinal nerve rather than the nerve root,
`possibly from hematoma in the psoas muscle. This compli(cid:173)
`cation has not been noted in subsequent patients.
`One patient developed sudden onset of radicular pain 6
`weeks postoperatively. X-ray films revealed that the facet
`screw on that side had migrated. It was removed percuta(cid:173)
`neously and the symptoms resolved.
`There have been no respiratory, cardiovascular, urinary,
`or wound complications.
`
`TECHNICAL TIPS
`As with any new procedure, operative time becomes short(cid:173)
`er as experience is gained. The original 4 1/2-hour operation
`now averages 21/2 hours. Lubricating the dilating cannulas
`with saline solution makes them easier to advance. The first
`view through the working cannula is always disconcerting
`because the annulus still has an overlying thin layer of mus(cid:173)
`cle fibers. Testing this layer with the neuro-monitoring ball
`probe can determine if a nerve is camouflaged within it.
`Nerves have been found at the superior margin of the can(cid:173)
`nula and can be retracted with a Love or similar retractor.
`Adequate visualization can be achieved by looking directly
`down the cannula; however, an arthroscope placed in the
`working cannula provides better light and excellent visual(cid:173)
`ization. A nerve at the margin of the cannula can be care(cid:173)
`fully retracted and is not a contraindication to proceeding.
`It should, however, be periodically released as one would do
`during a PLIF.
`Finally, carefu l patient selection and preoperative plan(cid:173)
`ning cannot be overemphas ized.
`
`OUTCOMES
`Experience with this approach to a lumbar interbody fusion
`is limited and short term. The numbe.r of cases and length
`of follow-up are not sufficient for more than anecdotal
`comments. However, interbody fusion supplemented with
`posterior screws across the facets is an established proce(cid:173)
`dure currently in use. 29 This chapter deals with a new surgi(cid:173)
`cal approach rather than a new procedure or implant. The
`outcome of this approach can therefore be judged without
`long-term patient follow-up. The goals in developing this
`surgical technique were to approach the lumbar spine in a
`minimally invasive manner, to be able to perform a stan(cid:173)
`dard operation through this approach, to be able to accu(cid:173)
`rately monitor the neural structures at risk, and to establish
`a technique that is reproducible.
`With these goals in mind, the outcome of this approach
`has been successful albeit limited in overall number of cas(cid:173)
`es. The initial single surgeon series has been extended to
`several other centers. Greater application of this approach
`is needed to demonstrate its reproducibility, but the experi(cid:173)
`ence to date is encouraging.
`
`KEY ANNOTATED REFERENCES
`Boucher HH. A method of spinal fusion.) Bone Joint Surg Br 41:248-
`259, 1959.
`This article is a historical description of a modification to the King
`transfacet fixation technique. In this technique, which has become
`known as the Boucher or King-Boucher technique, a longer screw is
`placed across the facet joint from superior to inferior but in the di(cid:173)
`rection of and taking purchase in the pedicle, increasing the potential
`stability of the construct. The author reports no known failures in
`160 single-level fusions and two failures in 15 multilevel fusions.
`Elias WJ, Simmons NE, Kaptain GJ, Chadduck JB, Whitehill R.
`Complications of posterior lumbar interbody fu sion when using
`a titanium threaded cage device. J Neurosurg 93(Suppl):45-52,
`2000.
`The authors present their PLIF experience with respect to incidence
`of complications. Neural complications were most significant, with a
`15% incidence of dural laceration and 9% incidence of postoperative
`radiculopathy revealed to be due to epidural fibrosis.
`Gu Y, Ebraheim NA, Xu R, Rezcallah AT, Yeasting RA. Anatomic con(cid:173)
`siderations of the posterolateral lumbar disk region. Orthopedics
`24:56-58, 2001.
`The authors present their anatomic findings of a surgical safe zone
`on the posterolateral lumbar disc between the anterior limit of the
`lumbar nerve and the posterior limit of the sympathetic tnmk. The
`safe zone was found to have a transverse dimension from 22 to 25
`mrn from the T12-Ll disc to the L4-L5 disc.
`Karnbin P. Arthroscopic microdiscectomy. Scrnin Orthop 6:97-108,
`1991.
`
`

`
`This is a historical description of an arthroscopic discectomy tech(cid:173)
`nique. The arthroscopic discectomy procedure described is performed
`through the triangular working zone at the posterolateral corner of
`the intervertebral disc bounded by the exiting root anterolaterally
`and the traversing root and dural sac medially. This working zone
`has come to be known as Kambin's triangle.
`Mayer HM. A new microsurgical technique for minimally invasive
`anterior lumbar inter body fusion. Spine 22:69 1-700, 1997.
`A series of patients who have undergone a minimally invasive ante(cid:173)
`rior lumbar interbody fusion via a microsurgical retroperitoneal lat(cid:173)
`eral approach to the spine for levels L2-L5 is reported. The retroperi(cid:173)
`toneal space is reached by a blunt, muscle-splitting approach and
`dissection of the psoas muscle attachments from the lateral border of
`the disc.
`Peloza J. Validation of n europhysiologic m onitorin g of posterolat(cid:173)
`eral approach to the sp ine via discogram procedure. Presented at
`the Ninth Internati onal Meeting on Advanced Spine Techniques,
`Montreux, Switzerland, May 2002.
`The Neuro Vision f]B system was used in this study to validate the
`neurophysiologic measu rement of relative nerve root-instrument
`distance during routine lumbar discogram procedures. In JO patients
`(38 levels) the neurophysiologic monitoring parameters changed pre(cid:173)
`dictably as the stimulating discography needle was advanced toward
`the disc, providing a relative measure of nerve root proximity.
`Rajaraman V, Vingan R, Roth P, Hea ry RF, Conklin L, Jacobs GB.
`Visceral and vascular complications resulting from anterior lum (cid:173)
`bar interbody fusion. J Neurosurg 91 (Suppl):60-64, 1999.
`The authors report the results of ALIF procedures in 60 patients, in
`which 24 general surgery-related complications occurred in 23 pa(cid:173)
`tients (38.3%), including sympathetic dysfunction, vascular injury,
`somatic neural injury, sexual dysfunction, prolonged ileus, wound
`incompetence, deep venous thrombosis, acute pancreatitis, and bow(cid:173)
`el injury.
`Stonecipher T, Wright S. Posterior lumbar interbody fusion with
`facet-screw fixation. Spine 14:468-471, 1989.
`The King-Boucher transfacet screw fixation technique is described in
`35 patients undergoing PLIF. Results were good or excellent in 34
`(97%) cases with interbody graft incorporation and no loss of fixa(cid:173)
`tion. There was one case of lamina fracture. The authors attribute
`the high fusion rate to the addition of rigid fixation and describe the
`fixation technique as simple, universally available, and inexpensive.
`Tsantrizos A, Andreou A, Aebi M, Steffen T. Biomechanical stability
`of five sta nd-alone anterior lumbar interbody fusion constructs.
`Eur Spi ne J 9: 14-22, 2000.
`A biomechanical comparison of different stand-alone ALIF cage con(cid:173)
`strncts and cage-related features on initial segment stability is pre(cid:173)
`sented. The authors found that stand-alone cages generally increased
`the nei1tral zone in all directions, suggesting potential initial segrnent
`instability or micromotion at the cage-endplate interface. Supple(cid:173)
`mentary posterior stabilization is rnggested, using pedicular, or
`translaminar or transarticular screws, the latt