Some time ago I was fortunate enough to be able to observe a new type of lumbar fusion called AXIALIF (for AXIAL Lumbar Interbody Fusion). This is ground breaking technology that provides the opportunity to perform a 360 fusion without abdominal surgery and without traditional posterior or lateral fusion techniques; effectively sparing the the patients' trunk muscles and minimizing collateral damage from the surgery. The surgery is described on the Trans1 website:
http://www.trans1.com/axiaLif_axiaLif_technology.html
This fusion technique is limited to single level L5-S1 or 2-level L4-L5-S1 procedures. The approach is through a small incision near the anus. Access to the disc space is provided by drilling through the sacrum to get to the L5-S1 disc space. After a discectomy is done, very ingenious hardware is implanted that allows the surgeon to 'jack up' and restore disc height, then pack the disc space with morselized bone, BMP.... whatever. If L4 is to be included in the surgery, they can drill through the L5 vertebral body to get to the L4-5 disc space.
Note that Trans1 also has hardware that will allow a flexible segment to be used in the disc space instead of the rigid fusion hardware, allowing for the possibility of a low invasive 1 or 2 level disc replacement to be implanted using much the same procedure. I first saw this equipment last year at SAS6 in Montreal and it looked very promising. Just by dumb luck, I sat next to a colorectal surgeon from Montreal... not attending SAS. I pulled out the Axialif brochures to discuss the approach.... is it as easy as the Trans1 people say? "I could do that approach in just a few minutes with my eyes closed!" was her reply.
Dr. Anthony Yeung and his team are amazingly efficient. Skin to skin time on this surgery was about 60 minutes, including the placement of the facet screws that accomplish the posterior part of the "360" fusion. This is a huge step forward for fusion technology. I don't know long term outcomes or relative recovery times or any other significant data that would help patients to evaluate this as an option... time will tell. I just know that I'm pleased to see such progress and innovation. At this point, this seems like a good option if you are considering fusion at these levels, but this is still spine surgery that comes along with all the uncertainty... it's about good diagnosis... proper surgical technique and experience.... then you still need some luck too,
Mark
PS... 95% of lumbar spine surgeries are performed at L4-5 and L5-S1.