Interbody fusion cage
File:Interbody fusion cage, cervical, Juliet s. L.jpg
File:Interbody fusion cage, L5S1, L.png
An interbody fusion cage (colloquially known as a "spine cage") is a prosthesis used in spinal fusion procedures to maintain foraminal height and decompression. They are cylindrical or square-shaped devices, and usually threaded. There are several varieties: the Harms cage, Ray cage, Pyramesh cage, InterFix cage, and lordotic LT cage, all of which are made from titanium; the Brantigan cage, made from carbon fibre; and the Cortical Bone Dowel, which is cut from allograft femur. The cages can be packed with autologous bone material in order to promote arthrodesis.
Such implants are inserted when the space between the spinal discs is distracted, such that the implant, when threaded, is compressed like a screw. Unthreaded implants, such as the Harms and Pyramesh cages have teeth along both surfaces that bite into the end plates.
Technology: expansion vs. static devices
Expandable implant devices are at the forefront of technology in this field, with cages that expand in place for optimal end-plate-to-endplate fit and correction of lordosis. There are several technologies for cage expansion; FLXfit by Expanding Orthopedics offers a unique and patented 3D articulation and lordotic expansion, Staxx by Spinewave stacks plates as risers, Varilift by Wenzel - uses a screw device for enlargement and AccuLIF by CoAlign, which has a unique locking hydraulic solution for precise expansion. FlareHawk by Integrity Implants uses stent-like technology, expanding in width, height, and lordosis.{{cn|date=November 2023}}
Once placed, the cages resist flexion and extension of the spine, and axial forces across the ventral and middle columns.
References
Further reading
- {{cite journal|journal=The Journal of Bone and Joint Surgery. American Volume|volume=81|issue=6|pages=859–880|year=1999|publisher=The Journal of Bone and Joint Surgery, Inc.|title=Current Concepts Review — Interbody Fusion Cages in Reconstructive Operations on the Spine|author=Paul C. McAfee|url=http://www.ejbjs.org./cgi/content/full/81/6/859|pmid=10391552|doi=10.2106/00004623-199906000-00014|url-access=subscription}}
- {{cite journal|doi=10.1097/00007632-199804010-00002|date=1988-04-01|volume=23|issue=7|journal=Spine|pages=758–765|title=Cervical Interbody Fusion Cages: An Animal Model With and Without Bone Morphogenetic Protein|author1=Thomas A. Zdeblick |author2=Alexander J. Ghanayem |author3=Andrew J. Rapoff |author4=Carol Swain |author5=Tim Bassett |author6=Mary E. Cooke |author7=Mark Markel |publisher=Lippincott-Raven|pmid=9563105|s2cid=24476957 }}
- {{cite book|title=Spine surgery: techniques, complication, avoidance, and management|volume=2|editor=Edward C. Benzel|edition=2nd|publisher=Gulf Professional Publishing|year=2005|isbn=978-9997639431|chapter=Lumbar Interbody Cages|author1=Branko Prpa |author2=Melvin D. Whitfield |author3=Isador H. Lieberman |pages=489 et seq}}
- {{cite book|chapter=Harms Cage|author1=Robert P. Melcher |author2=Michael Ruf |author3=Jürgen Harms |pages=738 et seq|title=Spinal instrumentation: surgical techniques|editor1=Daniel H. Kim |editor2=Alexander R. Vaccaro |editor3=Richard G. Fessler |publisher=Thieme|year=2005|isbn=978-1-58890-375-4}}
- {{cite journal|doi=10.1097/00007632-200109010-00007|date=2001-09-01|volume=26|issue=17|journal=Spine|pages=1850–1857|title=Biomechanical Comparison of Cervical Spine Interbody Fusion Cages|author1=Frank Kandziora |author2=Robert Pflugmacher |author3=Jan Schäfer |author4=Christian Born |author5=Georg Duda |author6=Norbert P. Haas |author7=Thomas Mittlmeier |publisher=Lippincott Williams & Wilkins|pmid=11568693 |s2cid=35417146 }}
- {{cite journal|date=2007-04-20|volume=32|issue=9|journal=Spine|pages=E275–E280|title=Treatment of Vertebral Osteomyelitis by Radical Debridement and Stabilization Using Titanium Mesh Cages|author1=Michael Ruf |author2=Dieter Stoltze |author3=Harry R. Merk |author4=Michael Ames |author5=Jürgen Harms |publisher=Lippincott Williams & Wilkins|doi=10.1097/01.brs.0000261034.83395.7f|pmid=17450059}}
- {{cite journal|date=2006-09-01|volume=31|issue=19|journal=Spine|pages=2189–2194|title=Effect of Lumbar Interbody Cage Geometry on Construct Stability: A Cadaveric Study|author1=Sasidhar Vadapalli |author2=Matt Robon |author3=Ashok Biyani |author4=Koichi Sairyo |author5=Ashutosh Khandha |author6=Vijay K. Goel |publisher=Lippincott Williams & Wilkins|doi=10.1097/01.brs.0000232720.23748.ce|pmid=16946652|s2cid=19511678 }}
- {{cite journal|doi=10.1097/00006123-199801000-00046|date=January 2008|volume=42|issue=1|journal=Neurosurgery|pages=200–205|title=The Ray Threaded Fusion Cage for Posterior Lumbar Interbody Fusion|author1=Stephen T. Onesti |author2=Ely Ashkenazi |publisher=Congress of Neurological Surgeons|pmid=9442526 }}
- {{cite book|title=The lumbar spine|editor1=Harry N. Herkowitz |editor2=Gordon R Bell |edition=3rd|publisher=Lippincott Williams & Wilkins|year=2004|isbn=978-0-7817-4297-9|chapter=Spinal Instrumentation Overview in Lumbar Degenerative Disorders: Cages|author1=Kenneth M. C. Cheung |author2=John C.Y. Leong |pages=286 et seq}}
- {{cite book|chapter=Spinal Instrumentation|author1=Vijay K. Goel |author2=Manohar M. Panjabi |author3=Huroshi Kuroki |author4=Setti S. Rengachary |author5=D. McGowan |author6=N. Ebraheim |pages=59 et seq|title=The lumbar spine|editor1=Harry N. Herkowitz |editor2=Gordon R Bell |edition=3rd|publisher=Lippincott Williams & Wilkins|year=2004|isbn=978-0-7817-4297-9}}
- {{cite journal|doi=10.1097/00007632-199701010-00005|date=1997-01-01|volume=22|issue=1|journal=Spine|pages=26–31|title=Posterior Lumbar Interbody Fusion: A Biomechanical Comparison, Including a New Threaded Cage|author1=Darrel S. Brodke |author2=Jeffrey C. Dick |author3=David N. Kunz |author4=Ronald McCabe |author5=Thomas A. Zdeblick |publisher=Lippincott-Raven|pmid=9122778|s2cid=21009248 }}
- {{cite journal|doi=10.1097/00007632-199106001-00020|date=June 1991|volume=16|issue=6S|journal=Spine|pages=S277–S282|title=A carbon fiber implant to aid interbody lumbar fusion. Mechanical testing.|author1=J. W. Brantigan |author2=A. D. Steffee |author3=J. M. Geiger |publisher=Lippincott-Raven|pmid=1862425|doi-access=free}}
- {{cite journal|doi=10.1097/00007632-199310001-00030|date=1993-10-15|volume=18|issue=14|journal=Spine|pages=2106–2107|title=A carbon fiber implant to aid interbody lumbar fusion. Two-year clinical results in the first 26 patients.|author1=J. W. Brantigan |author2=A. D. Steffee |publisher=Lippincott-Raven|pmid=8272967|doi-access=free}}