Abstract: An improved interbody fusion device incorporating anti-rotation features to inhibit accidental screwing or unscrewing of the fusion device in an intervertebral disc space. One such feature is a thread pattern having a crest diameter that increasingly tapers from a smaller diameter at the insertion end to a larger diameter at the opposite end making further advancement of the thread into the bone more difficult. Another feature is a thread cut out on the trailing edge of the thread, creating a barb which has a tendency to inhibit unscrewing. These features may be used alone or in combination for an improved interbody fusion device.

Abstract: An improved interbody fusion device incorporating anti-rotation features to inhibit accidental screwing or unscrewing of the fusion device in an intervertebral disc space. One such feature is a thread pattern having a crest diameter that increasingly tapers from a smaller diameter at the insertion end to a larger diameter at the opposite end making further advancement of the thread into the bone more difficult. Another feature is a thread cut out on the trailing edge of the thread, creating a barb which has a tendency to inhibit unscrewing. These features may be used alone or in combination for an improved interbody fusion device.

Abstract: An improved interbody fusion device incorporating anti-rotation features to inhibit accidental screwing or unscrewing of the fusion device in an intervertebral disc space. One such feature is a thread pattern having a crest diameter that increasingly tapers from a smaller diameter at the insertion end to a larger diameter at the opposite end making further advancement of the thread into the bone more difficult. Another feature is a thread cut out on the trailing edge of the thread, creating a barb which has a tendency to inhibit unscrewing. These features may be used alone or in combination for an improved interbody fusion device.

Abstract: A method and apparatus for performing an arthroscopic spinal laminectomy or similar surgical procedure includes a plurality of cannulas which are individually inserted, in a predetermined sequence, into predetermined areas of a patient's spinal column. The first inserted cannula has a tissue manipulating surface thereon which is used to create a working space adjacent a predetermined area of the patient's spinal column. A viewing device is inserted through this cannula and the fluid used in association therewith is used to maintain the working space. The second and third cannulas are larger in size and are working cannulas in that they provide passageways for instruments used in the surgical procedure. The second and third cannulas are utilized by the surgeon to sequentially remove a portion of the ligamentum flavum necessary to expose the desired area of the patient's spinal bone and, if necessary, to remove any portion of bone necessary to expose the nerve and disc area.