The Study | What They Don't Tell You | The Bottom Line
Ruetten S, et al (2009) "Full-endoscopic Anterior Decompression versus Conventional Anterior Decompression and Fusion in Cervical Disc Herniations." International Orthopaedics 33:1677-1682
Here is an interesting 2008 German investigation (Ruetten, et al) that pitted the traditional time tested anterior cervical discectomy {decompression} and fusion (ACDF) against a non--fusion endoscopic approach (full-endoscopic anterior cervical discectomy or (FACD).
The bottom line of this randomized controlled trial (that means this was a high-quality study) is this: after a two-year follow-up assessment of 103 patients, there was no significant clinical difference between the two techniques.
More specifically, "… 85.9% of the patients no longer had arm pain and 10% had occasional pain. There were no significant clinical differences between the decompression with or without fusion." (i.e. there was no difference between ACDF and FACD at the two-year follow-up). "The endoscopic technique afforded advantages in operation technique, rehabilitation, and (degree) of soft tissue injury."
Another advantage I can think of is the fact that patients would not have that big scar in the front of their necks! Yet another advantage: ACDF is associated with the dreaded "dominoe effect." That is, the discs above and below the site of fusion tend to fail secondary to the extra biomechanical stress placed upon them – this results in more surgery. With the endoscopic approach, although you may be damaging the disc, it is still there, so there is no disrupt of the biomechanics of the cervical spine, so no dominoe effect. [8]
WHAT THEY DON’T TELL YOU
After going over this investigation with a fine tooth comb, I have concluded that more editing needs to be done – it was not well written and downright confusing in some parts (I won't get into that). The biggest shock to me was the ineffectiveness of both surgeries with regard to the patient's neck pain. More specifically, while both surgeries drastically reduced the patients radiating arm pain (approximately 80 VAS down to 9 VAS @ two-year follow-up), neither of the them addressed the patient's neck pain (approximately 15.5 VAS down to 14.5 VAS!!!) {VAS = visual analog scale -you know, how much pain do you have on a scale of 0 to 100, where 100 is severe close to death pain and 0 is no pain at all} The other thing that jumped out at me was the fact that 24% of the patients suffered "advancing degeneration in the (operated) disk." Both surgical techniques resulted in decreased to space.
*Another absolutely shocking (well maybe not so shocking after you read the paper) thing about this paper was the fact that they excluded patients from the study who only had neck pain! (We will learn below that one possible reason for this exclusion is because with both surgical techniques none of the patients improved with respect to neck pain).
MY CONCERN: The biggest question that comes to my mind is what will this endoscopic group of patients look like in five years--I mean what will that disc look like? I would speculate that the degeneration caused by the surgery would progress in a significant number of patients to a point that would warrant fusion corrective surgery. And the obvious follow-up question to that is: in these patients that will need a future ACDF, what are the chances of that surgery being a success given that they've already had a prior surgery at that level? I would guess not as good.
MY BOTTOM LINE
Either the time-tested ACDF or the 'new kids on the block' (i.e., the FACD) are incredibly effective at relieving the radicular arm pain of patients of whom suffer paracentral cervical disc protrusion. However, they both stink at lessening the neck pain this cohort of patients (albeit, their VAS scores were probably about as low as they were going to get anyway). Too, I worry about the surgical future of patients who have undergone FACD: how many will require a revision surgery and how will that previous FACD affect the chances of a successful revision? Remember, according to the study at two years, 24% of them already had operation-induced degenerative changes in the disc. And all of them had loss of disc height (another sign of degeneration). Therefore, as Dr. Yeung honestly once admitted to me with regard to his SED procedure, a certain portion of these patients are undoubtedly going to succumb to reoperation via ACDF. So perhaps it is better to have ACDF the first time rather than risk a reoperation 5-7 years down the road? Only time will tell (hopefully somebody will do a five or seven year follow-up study on this group).