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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`NUVASIVE, INC.
`Petitioner
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`v.
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`WARSAW ORTHOPEDIC, INC.
`Patent Owner
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`Patent Number: 8,251,997 B2
`Issue Date: August 28, 2012
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`
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`DECLARATION OF BARTON L. SACHS, M.D., M.B.A.,
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`F.A.C.P.E., F.A.C.H.E.
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`Mail Stop “PATENT BOARD”
`Patent Trial and Appeal Board
`U.S. Patent and Trademark Office
`P.O. Box 1450
`Alexandria, VA 22313-1450
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`Case IPR2013-00206
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`WARSAW 2038
`NuVasive, Inc. v. Warsaw Orthopedic, Inc.
`Case IPR2013-00206
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`TABLE OF CONTENTS
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`Page
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`I.
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`ASSIGNMENT .............................................................................................. 1
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`II. QUALIFICATIONS ...................................................................................... 2
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`III. PERSON OF ORDINARY SKILL IN THE ART ...................................... 8
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`IV. MATERIALS CONSIDERED ..................................................................... 8
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`V.
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`BACKGROUND AND SUMMARY OF ʼ997 PATENT ........................... 9
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`A. Anatomy of the Human Spine ............................................................... 9
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`B.
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`C.
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`D.
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`Interbody Spinal Fusion Procedures ................................................... 14
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`The ’997 Patent ................................................................................... 28
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`Conception and Reduction to Practice of the ’997 Patent .................. 29
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`VI. CLAIM INTERPRETATION .................................................................... 33
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`VII. THE PRIOR LITIGATION BETWEEN THE PARTIES ...................... 42
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`VIII. NUVASIVE’S PROPOSED GROUNDS OF REJECTION DO
`NOT RENDER THE ʼ997 PATENT OBVIOUS ...................................... 46
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`A.
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`Proposed Grounds of Unpatentability ................................................. 46
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`1.
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`2.
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`Claims 1–8 (IPR2013-00206) ................................................... 46
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`Claims 9–30 (IPR2013-00208) ................................................. 47
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`B.
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`Prior Art References ............................................................................ 48
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`1.
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`2.
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`3.
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`U.S. Patent No. 4,545,374 (“Jacobson”) ................................... 48
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`Hansjörg F. Leu and Adam Schreiber, Percutaneous
`Fusion of the Lumbar Spine: A Promising Technique
`(“Leu”) ...................................................................................... 63
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`Brantigan ’327 ........................................................................... 68
`i
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`4. Michelson ’247 ......................................................................... 83
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`5.
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`U.S. Patent No. 5,569,290 (“McAfee ’290”) ............................ 89
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`C.
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`Combinations Suggested By Petitioner ............................................... 90
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`1.
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`2.
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`Jacobson in view of Leu and Brantigan (Claims 1–8, 17–
`23) ............................................................................................. 90
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`Jacobson in view of Leu and Michelson ’247 (Claims 1–
`8, 9–16, 24–30) ......................................................................... 94
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`IX. SECONDARY CONSIDERATIONS OF NON-OBVIOUSNESS .......... 96
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`X. APPLICABLE LEGAL PRINCIPLES ..................................................... 98
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`ii
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`I, Barton L. Sachs M.D., M.B.A., F.A.C.P.E., F.A.C.H.E. of Charleston, South
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`Carolina declare that:
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`I.
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`ASSIGNMENT
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`1.
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`I am a Professor of Orthopaedics and an Interim Chief Medical
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`Officer at the Medical University of South Carolina. I also serve as an Adjunct
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`Professor of Bioengineering at Clemson University, Department of Engineering
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`and Biomechanics. I am a practicing spine surgeon, specializing in minimally
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`invasive surgery, spinal arthroplastly and spine deformities, spine reconstruction,
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`and deformity surgery.
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`2.
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`I have been retained by counsel for Warsaw Orthopedic, Inc.
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`(“Warsaw” or “Patent Owner”). I understand that the Patent Trial and Appeal
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`Board (“PTAB” or “Board”) has instituted an inter partes review of Warsaw’s
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`U.S. Patent No. 8,251,997 (the “ʼ997 patent”) based upon a petition filed by
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`NuVasive, Inc. (“NuVasive” or “Petitioner”).
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`3.
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`I have been asked to opine on the subject of the validity of claims 1–
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`30 of the ʼ997 patent in light of the grounds of rejection at issue in this inter partes
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`review. I have also been asked to review and respond to the Declaration of
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`Dr. Paul McAfee (the “McAfee Declaration” or “Ex. 1001”) submitted in support
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`of NuVasive’s petition for inter partes review.
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`4.
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`In forming my opinions as set forth in this declaration, I have relied
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`upon my education, research, training, and experience in the area of spinal surgery.
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`I have also relied on my review and analysis of the prior art and information
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`provided to me in connection with this case.
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`5.
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`I am being compensated for my work as an expert with respect to this
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`inter partes review, but my compensation is not contingent in any way on the
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`content of my opinions or the outcome of this proceeding.
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`II. QUALIFICATIONS
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`6.
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`I received my Bachelor of Arts, cum laude, with honors in Biology in
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`1973 from Harvard University and my Doctorate of Medicine in 1977 from State
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`University of New York. Following medical school, I served as a Resident in
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`orthopaedics at the Case Western Reserve University Hospitals of Cleveland,
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`Ohio, from 1977 to 1982. From 1982 to 1983, I was the Chief Resident in
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`Orthopaedic Surgery at Case Western. In 1998, I received a Masters of Business
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`Administration from Rensselaer Polytechnic Institute in Troy, New York.
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`7.
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`I have completed a number of fellowships. From June through
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`August of 1974, I was a Clinical and Educational Research Fellow at the
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`Department of Orthopaedic Surgery at the S.U.N.Y. Upstate Medical Center in
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`Syracuse, New York, sponsored by Richard T. Chiroff, M.D. From November of
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`1978 through October of 1979, I held a Research Fellowship in Cartilage Disease
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`and Bone Growth at the Cartilage Research Laboratories of the Departments of
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`
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`2
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`
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`Orthopaedics and Medicine, Division of Rheumatology, at Case Western Reserve
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`University Hospitals and School of Medicine under Victor M. Goldberg, Director
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`and M.D. From July 1983 through June of 1984, I completed the John H. Moe
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`Scoliosis Fellowship at Twin Cities Scoliosis and Spine Center, University of
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`Minnesota, working in clinical operative and spinal surgical training for the
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`treatment of spinal disorders under David S. Bradford, Director and M.D.
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`8.
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`I have been licensed to practice medicine for over 30 years, and hold
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`Medical Licenses in New York, Minnesota, Texas, New Hampshire (not renewed),
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`Massachusetts (not renewed), Arizona, and South Carolina. I have been a board
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`certified orthopaedic surgeon since 1988, was recertified by the American Board of
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`Orthopaedic Surgery (ABOS), and was recertified by the American Board of Spine
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`Surgery (ABSS). I also hold a board certification as a Physician Executive and as
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`a Certified Health Care Executive. I hold fellowship in A.C.P.E. and A.C.H.E.
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`9. My current surgical practice includes standard operative procedures
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`such as discectomies, laminectomies, and decompression procedures, as well as
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`more complex reconstructive spine operations with fusions, implant devices,
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`deformity corrections, osteotomies, and advanced technology operations which
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`include minimally invasive and endoscopic surgery of the spine. I began
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`performing lateral approach procedures endoscopically in the mid-1990s. I have
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`since advanced that technique with new instruments and technology available as
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`3
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`part of my standard clinical practice over the last fifteen years.
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`10.
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`I have been teaching medicine and surgery since 1985 and have held
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`various academic appointments ever since. I have been an Assistant Professor of
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`Orthopaedic Surgery at the University of Texas and Tufts University Medical
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`School. From 1994 to 2000, I was an Associate Professor of Surgery and Physical
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`Medicine and Rehabilitation at Albany Medical College in New York. From 2000
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`to 2009, I taught as an Adjunct Professor of Surgery in Orthopaedics at Albany
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`Medical College. Currently, I am a Professor of Orthopaedics at the Medical
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`University of South Carolina in Charleston. I am also currently a Professor of
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`Biomedical Engineering at Clemson University.
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`11. My major research interests and accomplishments broadly involve
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`clinical spine evaluation and treatment outcome studies as well as scientific
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`laboratory research projects. Specifically, I have lead clinical developments of
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`minimally invasive spinal surgical techniques, including laparoscopic lumbar
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`spinal fusions, thoracoscopic spinal surgery, endoscopic percutaneous discectomy,
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`and spinal arthroplasty development.
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`12. My laboratory research includes the study of bone growth stimulation
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`enhancement by recombinant cellular mitogen devices, use of biologically
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`manufactured bone void filler material for fusions, use of artificial disc
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`replacements, and the development of intradiscal spinal implant fusion devices.
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`4
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`13.
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`I have also conducted various animal studies involving in vitro and in
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`vivo research studies with multiple, varied species of quadraped and biped animals
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`(including goats, sheep, baboons, canines, bovines, and swine). These studies
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`involved interbody fusion and stabilization as well as bone-growth stimulation,
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`motion preservation, development of techniques for minimally invasive surgical
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`approaches to the spine, and vertebral disc space function.
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`14.
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`I also conducted clinical outcomes research of operative
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`decompressions of cervical spinal stenosis, lumbar discectomies, cervical
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`discectomies, fusion procedures, and lumbar interbody implant fusion devices.
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`15. This research has included work on spine and disc spaces, evaluating
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`various implants, fusion devices, and motion preservation devices, and
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`development of new and dynamic techniques and surgical procedures, including
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`minimally invasive surgical procedures for spine applications. The aim of my
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`career’s research has been to conceive of and develop products and techniques in
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`laboratory research, to practice and refine these concepts in animal studies, and,
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`after perfection, ultimately apply my research in clinical settings to improve patient
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`care.
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`16.
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`I am the principal author or co-author of over 105 medical and
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`scientific publications, including peer-reviewed journal articles, non-peer reviewed
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`papers presenting primary data, book and scholarly chapters, and peer-reviewed
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`5
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`submissions and presentations with published abstracts. I have been invited
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`numerous times to lecture on various topics related to my medical practice and
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`research, acted as course director for various educational courses outside of my
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`professorships, and have authored various electronic and poster publications
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`detailing surgical techniques and medical summaries.
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`17.
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`I am a named inventor on U.S. Patent No. 6,325,808 (Robotic system,
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`docking station, and surgical tool for collaborative control in minimally invasive
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`surgery). I have also developed a number of devices, including a percutaneous
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`facet screw system in approximately 1997, which was ultimately manufactured and
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`sold by DePuy. I received royalty payments for commercial use of this system.
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`Other devices I developed that are used in spine surgeries include the PathFinder
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`percutaneous facet screw system manufactured by Spinal Concepts (this product
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`was later exploited by Abbot and Zimmer); the Paramount percutaneous pedicle
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`screw system manufactured by Innovative Spine Technologies (IST); the Integra
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`Plate System, an anterior lumbar plate system that I developed with Synthes; and a
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`posterior pedicle screw system manufactured by Globus for use in deformity
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`correction applications. My inventive and product development activities have
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`focused on developing technologies that can be made available for use by myself
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`and other surgeons in clinical settings to improve patient care and outcomes.
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`18.
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`I am a member of several professional organizations, including the
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`6
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`North American Spine Society (“NASS”) (sitting liaison for coding committee)
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`and the Scoliosis Research Society (liaison for coding with NASS). Over the span
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`of my career, I have also held various Board and Fellow positions in international,
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`national, and regional professional organizations including the American
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`Association for Orthopaedic Surgeons, American College of Surgeons, the
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`International Society for Study of the Lumbar Spine, the International Intradiscal
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`Therapy Society, American Board of Spine Surgery, and many others. I have also
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`served on various committees of the Scoliosis Research Society, American Board
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`of Spine Surgery, and North American Spine Society.
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`19.
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`I have received numerous awards, including the American Medical
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`Association Physician’s Recognition Award for CME, Competitive Research Grant
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`Award for the North American Spine Society, and the Regents Scholarship Award.
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`20.
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`In addition to my surgical, research, and academic experience, I was a
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`founder and President of TBI Clinical Research Organization, a company formed
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`to conduct numerous clinical trial studies for spinal device research applications. I
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`was also a founder and President of Texas Back Institute Research Foundation, a
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`company formed to capture intellectual property and related concepts for spine
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`devices and implants and incubate the devices through the value chain of
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`development. I was also a Founder and President of Musculoskeletal Research
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`Corporation (MSRC), which later became Innovative Spine Technologies, Inc.
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`7
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`(IST), where I served as a member of the board of directors. IST manufactured,
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`marketed, and sold spine-related devices commercially. I have also held other
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`positions with various medical companies and facilities as listed in my curriculum
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`vitae.
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`21. A true and correct copy of my curriculum vitae is attached to this
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`expert report (see Appendix A); it includes a full list of my qualifications,
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`including past positions and publications.
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`III. PERSON OF ORDINARY SKILL IN THE ART
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`22.
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`It is my understanding that a person of ordinary skill in the art
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`(“POSITA”) at the time of the effective filing date of the application that lead to
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`the ʼ997 patent is a surgeon with extensive knowledge of the human anatomy, the
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`use of devices in the human spine, and the biomechanical, anatomical, and
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`physiological implications of such use. My opinions are thus based upon the
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`perspective of a POSITA at the time of the effective filing date of the application
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`that led to the ’997 patent.
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`IV. MATERIALS CONSIDERED
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`23.
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`In preparing this declaration, I have read the claims, specification, and
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`prosecution history of the ’997 patent. I have also considered NuVasive’s two
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`petitions for IPR regarding the ’997 patent (IPR2013-00206 and IPR2013-00208),
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`including the supporting materials and references such as the Declaration of
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`8
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`Dr. Paul McAfee (“McAfee Declaration”) and Dr. McAfee’s deposition transcript
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`from these proceedings, as well as all of the materials submitted to the Board in
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`these proceedings. I also reviewed a variety of case-related documents from the
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`parties’ prior litigation, as well as trial and deposition testimony from that case. In
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`addition, I have considered the various documents referenced in my declaration.
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`Of course, my opinions are also based on the knowledge I have accumulated over
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`my years of experience as outlined above.
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`V. BACKGROUND AND SUMMARY OF ʼ997 PATENT
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`24. This section provides an overview of the relevant anatomy,
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`pathologies, technological background, and the ’997 patented technology. The
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`’997 patent, entitled, “Method for Inserting an Artificial Implant Between Two
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`Adjacent Vertebrae Along a Coronal Plane,” issued on August 28, 2012 from an
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`application filed on November 29, 2011. I understand that the application that
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`issued as the ’997 patent is a continuation of an application filed on February 21,
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`2003, which is a continuation of an application filed on June 7, 1995, which is a
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`division of an application filed on February 27, 1995, that ultimately issued as U.S.
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`Patent No. 5,772,661. See Ex. 1002 at 1:5–11.
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`A. Anatomy of the Human Spine
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`25. The ’997 patent relates to the treatment of diseases of the human spine
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`and, more particularly, to methods for performing surgical procedures on the
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`9
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`human thoracic and lumbar spine. Id. at 17–19. To place the technology of the
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`’997 patent in context, it is thus necessary to provide an overview of the relevant
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`anatomy of the human spine.
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`26. The human spine, or vertebral column, consists of 26 bones, including
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`24 vertebrae, the sacrum and the coccyx. The vertebrae provide a column of
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`support, bearing the weight of the head, neck, and trunk, ultimately transferring
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`that weight to the skeleton of the lower limbs. The vertebral column also protects
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`the spinal cord. Anterior to the vertebral column lie the great vessels, the aorta and
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`vena cava. The spinal cord and great vessels can be seen in the figures below.
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`10
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`27. As depicted above, the vertebral column is divided into regions. The
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`cervical spine begins at the skull and consists of seven vertebrae constituting the
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`neck and extending inferiorly to the trunk. Below the cervical region lie the twelve
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`thoracic vertebrae that form the mid-back regions and articulate with one or more
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`pairs of ribs. Five lumbar vertebrae form the lower back, with the fifth articulating
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`with the sacrum, which in turn articulates with the coccyx. The cervical, thoracic,
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`and lumbar regions consist of individual vertebrae.
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`28. As depicted below, each vertebra has three basic parts: (1) a body,
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`(2) a vertebral or neural arch, and (3) articular processes. The body of the vertebra
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`transfers weight along the axis of the vertebral column and is separated from
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`neighboring vertebrae by the intervertebral disc. The intervertebral disc is a
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`unique, complex structure composed of fibrocartilage, articular cartilage, mucinous
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`material (disc material), and collagen ligament material, and attaches to the bony
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`endplate. The intervertebral discs serve multiple functions. For example, they
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`serve as “shock absorbers,” having soft spongy centers (known as the nucleus
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`pulposus), which are surrounded by tough outer rings of circular containment
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`collagen ligament tissue (known as the annulus fibrosus).
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`11
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`The intervertebral disc also serves to provide stability and support at the vertebral
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`adjacent motion segments and space that protects spinal nerves and exiting nerve
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`roots and the central spinal column, as well as allows a relatively restricted range
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`of motion between two adjacent vertebral bodies.
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`29. The portion of the vertebral body adjacent to the nucleus pulposus of
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`an intervertebral disc is covered by a thin layer of dense, subchondral bone known
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`as the vertebral endplate. The vertebral endplate has a central region of condensed,
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`cancellous bone. Toward the vertebral periphery lies a thin, strong layer of dense
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`bone known as the apophyseal ring that serves as the attachment site for the
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`annulus fibrosus of the intervertebral disc. At the very edge of the vertebral body
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`lies the cortical rim, which is distinct from the apophyseal ring. The apophyseal
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`ring, in turn, is anatomically distinct from the vertebral endplate. For example, the
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`vertebral endplate, which is proximate to cancellous bone, is typically vascular,
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`whereas the apophyseal ring is almost entirely avascular. As a result, little fusion
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`12
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`is possible in the avascular apophyseal ring. Blood capillaries often run through
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`the vertebral endplate into the nucleus pulpous. These blood capillaries play an
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`important role in an interbody fusion procedure because they facilitate the growth
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`of new bone. The following (annotated) images illustrate the boundaries of a
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`typical vertebral endplate, and indicate that the endplates are distinct from the
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`apophyseal ring.
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`Source: Kinesiology of the Musculoskeletal System, Foundations for
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`Rehabilitation, Second Edition, Donald A. Neumann, 2010, Mosby Elsevier, ISBN
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`13
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`978-0-323-03989-5
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`Source: The Lumbar Intervertebral Disc, Frank M. Phillips, Carl Lauryssen, 2010,
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`ISBN 978-1-60406-048-5
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`B.
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`Interbody Spinal Fusion Procedures
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`30. The goal of a spinal fusion procedure is to surgically induce the union
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`or healing of bone. For example, the objective of an interbody spinal fusion
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`procedure is to induce bone growth between two vertebrae into a single bony
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`bridge using surgery. This bridge serves to immobilize the vertebrae to alleviate
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`the pain caused by motion, promote stability, and in certain cases, restore lordosis
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`(the natural curvature of the spinal column). Interbody spinal fusion is one of
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`many types of spinal fusion procedures. For example, fusion of the posterior
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`column of the spine (e.g. fusion of adjacent spinous processes or transverse
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`processes) is another type of spinal fusion. These fusions of the posterior column
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`are often performed without an implant. Based on his deposition testimony in this
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`proceeding, I believe Dr. McAfee would agree with this statement. See Ex. 2039
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`at 26:12–27:1.
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`31. Today, spinal fusion is predominantly facilitated by the insertion of a
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`spinal fusion implant, usually with some bone growth agent impacted in or
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`provided in combination with this implant. However, spinal fusion implants have
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`not always been used in interbody fusions. Many surgeons and commenters credit
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`14
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`Dr. Bagby with the development of the first interbody spinal fusion implant.
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`Dr. Bagby’s original fusion implant was a cylindrical basket that he developed
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`through the 1980’s. Much of this early work by Dr. Bagby is disclosed in his U.S.
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`Patent No. 4,501,269 (published in 1985) and in a publication authored by
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`Dr. Bagby entitled “Arthrodesis by the Distraction-Compression Method Using a
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`Stainless Steel Implant,” which was published in 1988. It was not until the late-
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`1980’s that development of spinal fusion implants began in earnest and
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`experimental use of these implants began in human patients. Prior to the late-
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`1980’s, interbody fusions were performed using graft material from the patient’s
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`own body (autograft) or from a donor (allograft) without any artificial interbody
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`structural support. See, e.g., Ex. 1002 at 2:49–52 (discussing prior art method of
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`posterolateral interbody fusion with “tiny fragments of morsalized bone”); Ex.
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`1005 at 600 (interbody fusion with “graft conglomerate”); U.S. Patent No.
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`4,917,704 (Ex. 1007) at 1:7–31 (interbody fusion with “bone splinters”).
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`32. The ’997 patent relates generally to a method of inserting an
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`interbody, intraspinal fusion implant for use in an interbody spinal fusion surgery.
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`Briefly, the methods of the ’997 patent recite a direct lateral surgical path to an
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`intervertebral space, through which a series of increasingly wider surgical
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`instruments and, ultimately a spinal fusion implant, are passed. I discuss the
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`particular limitations at issue in the claimed methods below. Suffice it to say for
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`15
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`now, the claimed fusion implants are dimensioned to fit in the interbody space
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`between two adjacent vertebrae to permit bone bridging between adjacent
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`vertebrae and the implant to ultimately achieve fusion of the adjacent vertebrae.
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`See Ex. 1002 at 3:18–30.
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`33. The direct lateral approach to the interbody space allows an anatomic
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`pathway into the disc space that avoids traversing the major nerve roots that are
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`exiting the spinal cord. As compared to a posterior or posterolateral approach,
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`surgeons using a direct lateral approach are less likely to encounter major nerves,
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`and the nerves that are encountered are more easily displaced and moved out of the
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`way (i.e. they are untethered).
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`34. Conditions for which spinal fusion are performed include
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`degenerative disc disease, spinal fracture secondary to traumatic injury, scoliosis
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`(abnormal curvature of the spine), spondylolisthesis (anterior displacement of a
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`vertebra), spondylosis (osteoarthritis of the vertebral joints), spinal disc herniation,
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`and other spinal instability caused by degeneration of the vertebrae.
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`35. Most commonly, spinal fusion is used to treat degenerative disc
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`disease, which refers to the gradual deterioration of the intervertebral discs
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`between the vertebrae in the spine. As the body ages, the annulus fibrosus may
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`wear and eventually crack, while the inner portion of the intervertebral discs may
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`lose water content, causing the disc to become thin and stiff. As this occurs, the
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`16
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`
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`shock absorption properties of the discs weaken, and the nerve openings along the
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`sides of the spine narrow, leading to pinched nerves. Abnormal motion between
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`the vertebrae also results, causing pain.
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`36. Historically, the more common approaches to the spine were either an
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`anterior, posterior, or posterolateral approach to the intervertebral disc space. Id. at
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`2:37–52. As explained in the ’997 patent, these approaches pose significant risks
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`to either the great vessels (abdominal aorta and inferior vena cava), running
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`anterior to the vertebral column, or the spinal cord, running posterior to the
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`vertebral bodies. Id. at 3:18–30.
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`37.
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`In an anterior procedure, for example, the surgeon performing the
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`operation prepares the disc space and implants the spinal device from an anterior
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`approach or via the patient’s front through the abdomen. This approach risks
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`damage to the aorta and vena cava that lie anterior to the spine and must be
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`retracted, often requiring a second “access surgeon.” This is particularly the case
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`lower in the lumbar spine where the aorta and vena cava split and make anterior
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`access to an intervertebral disc space very difficult. Id. at 2:67–3:3. In an anterior
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`approach, the maximum length of an implant that can be inserted is limited by the
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`depth of the vertebrae, and further limited by the safety margin needed to minimize
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`risk to the great vessels and spinal cord, resulting in a relatively small contact area
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`for fusion between the implant and the vertebral endplates of adjacent vertebrae.
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`17
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`38. The posterior approach to the spine traverses back support muscles to
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`access a posterior aspect of the intervertebral disc space. The posterior approach
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`has the benefit of a relatively shorter surgical channel to the spine, however, this
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`approach risks damages to the spinal cord and spinal nerves. Id. at 2:45–49.
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`39. As Dr. Michelson explains in the ’997 specification, in the mid-1990’s
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`the posterolateral approach “has generally been utilized as a compliment to
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`percutaneous discectomy and has consisted of pushing tiny fragments of
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`morsalized bone down through a tube and into the disc space.” Id. at 2:49–52.
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`40. The anatomical constraints imposed by anterior and posterior
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`approaches to the intervertebral space limit the efficacy of the interbody implants
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`that can be used, primarily by limiting the size of the implants to the dimensions of
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`the vertebrae relative to the direction in which the implants were inserted. Id. at
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`3:18–30. As the ’997 patent explains, the maximum possible length for an implant
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`that is inserted from either the front or the back of the patient is limited to the depth
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`of the vertebrae, measured from the anterior to the posterior end of the vertebrae,
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`and further limited by safety considerations attendant to the vessels and nerves
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`adjacent to the vertebra. Id. To promote fusion and provide stability, however, a
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`spinal implant must be large enough to occupy a sufficient portion of the transverse
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`width of a vertebral body. Id. As a result of the structural limitations on spinal
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`implants inserted anteriorly or posteriorly, surgeons often used multiple implants.
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`18
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`
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`Id. at 20:42–54. Figures 31 and 32 demonstrate the prior anterior approach with
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`two implants:
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`41. The direct lateral approach of the methods claimed by the ’997 patent
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`and the resulting placement of a spinal implant is illustrated in Figures 30 and 31
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`of the ’997 patent. Dr. Michelson explains, “It can be seen from Fig. 30 that the
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`implant I has a true lateral orientation with respect to the vertebra L4 such that
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`there is a great area of contact between the implant I and the vertebrae L4.” Id. at
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`20:31–34.
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`As illustrated by Figure 30, when inserted from a direct or “true” lateral approach,
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`the implant disclosed by Michelson occupies substantially the full transverse width
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`19
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`of the vertebral body.
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`42.
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`I have been a practicing surgeon for over 30 years and am not aware
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`of any surgeons who performed a direct lateral interbody implant fusion procedure
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`prior to 1995. This is consistent with Dr. Michelson’s disclosure in the ’997 patent
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`that, at the time of filing his disclosure in 1995, “interbody fusions have been
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`performed from posterior, posterolateral, and anterior” approaches. Id. at 2:41–42.
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`Consultants for NuVasive—Dr. Mark D. Peterson and Dr. William D. Smith—
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`stated that in 1994, “all lower spine surgery was ‘open surgery’ wherein the spine
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`was accessed from either the front (anterior) or the back (posterior).” Ex. 2043 ¶¶
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`2, 4; Ex. 2044 ¶¶ 2, 4.
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`43.
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`In the past, surgeons utilized a lateral path to the spine only when
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`required by a certain pathology or patient condition. For example, a lateral
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`approach may have been utilized to address the following clinical indications:
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`tumors, unstable fractures of the vertebral body with nerve compression, or spine
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`deformity (e.g. scoliosis, kyphosis, etc.). In other words, the lateral approach to
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`the spine was reserved for situations when it was necessary. In a corpectomy
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`procedure—the removal of a vertebral body, in part or in full—an anterior
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`approach to the spine in the thoracic or thoracolumbar region is not anatomically
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`possible. The heart, aorta, vena cava, duodenum, renal vessels, and the esophagus
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`all block an anterior approach in this area of the spine. Similarly, a posterior
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`20
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`
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`approach to spine in a corpectomy procedure is difficult, if not impossible, because
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`the spinal canal with spinal cord lies directly posterior to the vertebral body being
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`removed. Thus, out of necessity, the surgeon must utilize a lateral approach to the
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`spine. I note, however, a corpectomy would not be performed using the direct
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`lateral approach in the lumbar spine because the psoas muscle prevents removal of
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`vertebral body in that direction, and therefore, a more oblique approach would be
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`utilized in that situation.
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`44.
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`In 1994, surgeons appreciated the benefits of performing interbody
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`fusions using anterior, posterior, or posterolateral approaches. For example,
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`benefits to the anterior approach included direct access to the disc, the ability to
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`completely eradicate and remove the disc, the ability to release the anterior
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`longitudinal ligament for better distraction, and the ability to avoid nerve roots that
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`would otherwise be dealt with in the posterior approach. With the posterior
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`approach, surgeons appreciated that it provided a shorter surgical path, and the
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`ability to avoid the need to manipulate the great vessels. Regarding the
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`posterolateral approach, surgeons appreciated the comparatively unobstructed path
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`to the disc space for minor fusion procedures, which still traversed the paraspinal
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`and psoas muscles but avoided the patient’s bowel and peritoneum. The
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`posterolateral approach is approximately sixty degrees off midline. Content with
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`these prior art approaches, surgeons at the relevant time did not appreciate the
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`21
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`benefits of a direct lateral approach to the spine for an interbody fusion procedure,
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`including the ability to place a very long implant across the disc space to provide
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`for more biomechanical stability and contact area for