ACDF
Fusing the level instead of replacing the disc. Suits a wider range of anatomy and remains the right choice in many necks.
Compare the two ›Cervical disc replacement (artificial disc)
The same operation as an ACDF up to the point the disc comes out. Instead of fusing the level, a mobile artificial disc goes in, so it keeps moving. In the right patient the evidence at seven years is genuinely good, with fewer people needing further surgery than after a fusion.
At a glance
Anaesthetic
General
Approach
From the front of the neck
Hospital stay
Approximately 1 to 3 days
Levels treated
Usually one or two
Driving
Restricted for about 4 to 6 weeks
Swimming
Avoided for 4 to 6 weeks
Lifting
Heavy lifting avoided early on
Fusion
None, motion preserved
These are the practice's published recovery figures for this operation. Lifting, bending and twisting may also be restricted, and how quickly each restriction lifts depends on how your own recovery progresses.
WHAT IT INVOLVES
Replace the disc rather than remove the joint
The approach, the incision and the decompression are the same as an ACDF. The difference is what goes into the space afterwards, and what that means for the years that follow.
1
The level still bends and rotates after surgery
2
Artificial disc: two endplates with a mobile core between them
3
Untreated disc at the level below, left alone
01
Identical up to a point
Same small incision in a crease at the front of the neck, same route between the tissue planes, same removal of the disc and whatever is pressing on the nerve or cord. If you have read about ACDF, you already know most of this operation.
02
The endplates have to fit well
The device is sized to your anatomy and seated precisely against prepared bone surfaces. Positioning matters more here than with a fusion, because a device that is not sitting well will not move the way it should.
03
Nothing has to knit together
There is no fusion to wait for, which is why the hospital stay published for this operation is shorter than for a fusion. It also means smoking, which is a real problem for fusion, is less of an obstacle here, though it remains bad for healing generally.
WHO IT SUITS
Selection is the whole game with this operation
Disc replacement performs well in the right neck and poorly in the wrong one. Being turned down for it is not bad news; it means the anatomy would not support it.
A good fit when
A single level, or sometimes two, is causing nerve compression
The level still has reasonable movement and height to preserve
Good bone quality and normal alignment through the neck
Younger and more active patients, where decades of neighbouring levels matter
Not suitable when
The level is already stiff, collapsed or heavily worn
There is instability, significant deformity or poor bone quality
Extensive facet joint arthritis, which is itself a pain source motion will not help
Widespread multi-level cord compression, where decompression matters more than motion
THE EVIDENCE
What seven years of trial data actually shows
This is one of the better-studied questions in spine surgery, because artificial discs had to be trialled against fusion to be approved. A meta-analysis pooled 11 randomised trials.
4.3% vs 10.8%
Surgery at a neighbouring level, by 7 years
After a single-level procedure, 4.3 per cent of disc replacement patients needed surgery at an adjacent level within seven years, against 10.8 per cent after ACDF. The difference was statistically significant.
Journal of Spine Surgery, 2020
5.2% vs 12.7%
Further surgery at the treated level, by 7 years
Reoperation at the original level was also lower after disc replacement, 5.2 per cent against 12.7 per cent for ACDF. A similar pattern held for two-level procedures.
Journal of Spine Surgery, 2020
How to read this
At two years the two operations were not significantly different: 2.3 per cent against 3.6 per cent for adjacent-level surgery. The advantage only becomes clear with time, which is exactly why it matters more for a patient in their forties than for one in their seventies.
These are averages from selected trial populations, and patients in those trials met strict criteria. If your anatomy does not meet similar criteria, the results do not transfer to you. That is the honest limit of this evidence, and it is why selection is discussed so carefully.
RISKS, HONESTLY
What can go wrong, and how often
Common, usually temporary
Difficulty swallowing
Same front-of-neck approach as an ACDF, so the same early sore throat and odd swallowing for days to weeks. It settles in the large majority of people.
Uncommon
Voice change or hoarseness
A nerve to the voice box runs close to the approach. Temporary change happens; lasting hoarseness is uncommon.
Variable, often silent
Unwanted bone forming around the device
Bone can grow around the implant over time and gradually reduce the movement it was placed to preserve. Often it causes no symptoms, but it can partly defeat the purpose of the operation.
Uncommon
Device problems
The implant can sit less well than intended, settle, or rarely move from position. This is the main reason precise sizing and placement matter so much.
About 1 in 19 by 7 years
Further surgery at the same level
Pooled trial data found 5.2 per cent needed reoperation at the treated level within seven years, against 12.7 per cent after ACDF.
Under 1 in 100
Nerve or cord injury, infection
As with any anterior cervical operation these are uncommon. National data for the anterior approach records neurological complications in roughly 0.3 to 0.6 per 100 and wound infection well under 1 in 100.
One honest caveat about the evidence base: many of the trials comparing artificial discs with fusion were funded by device manufacturers, which is normal for approval studies but is worth knowing when reading strongly positive results. The adjacent-level findings above come from a pooled analysis of randomised trials rather than a single study, which is the more reliable form of that evidence.
RECOVERY
What recovery involves
IN HOSPITAL
Approximately 1 to 3 days
The practice's guidance for disc replacement is a hospital stay of about one to three days, shorter than the three to five days published for a fusion. A physiotherapist assesses your recovery before you go home.
AT HOME
Looking after the wound
Keep the wound clean and dry, adapting bathing or covering it as instructed, and avoid touching it. Unlike a fusion, there is nothing at the treated level that has to knit together.
4 TO 6 WEEKS
Driving and swimming
Driving is restricted for approximately four to six weeks, depending on how recovery progresses, and swimming is avoided for four to six weeks.
GOING BACK TO WORK
Modified duties, then lifting
A temporary return on modified or restricted duties is common. Heavy lifting is avoided during the initial recovery period, and lifting, bending or twisting may be restricted while you recover.
Preserving motion is worth having. It is not worth having in the wrong neck
In a stiff, collapsed or unstable level there is little movement left to preserve, and a device placed there will not do what it was chosen to do. Being turned down for an artificial disc is not bad news: it means the anatomy would not support one, and a fusion is the better operation rather than a consolation prize.
COMMON QUESTIONS
The things people ask most
Is disc replacement better than fusion?
Better for the right patient, not better in general. At seven years it shows lower rates of further surgery, but only in people whose anatomy suits it. In a stiff, collapsed or unstable level a fusion is the better operation, and it is not a consolation prize.
How long does an artificial disc last?
Trial follow-up extends to around seven years with most devices performing well. Beyond that the data thins out, because these implants have not been in use long enough. That uncertainty is a genuine consideration for a young patient.
Will I set off airport scanners?
Generally no. Modern implants are small and typically do not trigger security screening. It is worth mentioning if you are asked, but it is not something to plan around.
Can I have an MRI afterwards?
Yes. Current cervical disc implants are MRI compatible, though the images immediately around the device can be less clear.
What if the device fails?
It can be converted to a fusion. That is a bigger operation than the original, but it is a well-established fallback, and knowing the exit exists is part of judging the risk.
Why was I offered a fusion instead?
Usually because something about the level rules out an artificial disc: it is too worn or stiff, the alignment is off, the bone quality is not adequate, or the facet joints are arthritic. Ask specifically which of those applies to you. It should be a clear answer.
ALTERNATIVES
The other options worth knowing about
Posterior foraminotomy
Frees a trapped nerve from the back without any device at all. Also motion preserving, with its own trade-offs.
About foraminotomy ›Non-surgical treatment
Most nerve pain settles without surgery. Unless the cord is at risk, this comes first.
Do I need surgery? ›About this information
This page is general information about a procedure and is not advice about your own case. The outcome and complication figures come from the published studies listed below and describe large groups of patients. The recovery figures are the practice's published guidance for this operation, not a commitment about your own recovery. More about Dr Tollesson.
References
Cervical disc arthroplasty versus anterior cervical discectomy and fusion: a meta-analysis of rates of adjacent-level surgery to 7-year follow-up. Journal of Spine Surgery, 2020, pooling 11 randomised controlled trials, for the adjacent-level and index-level reoperation rates quoted above.
Surgeon Procedure Volume and Complication Rates in Anterior Cervical Discectomy and Fusions. Clinical Spine Surgery, 2017, for anterior approach complication rates.
Whether your anatomy supports an artificial disc is settled by your imaging.
A consultation will tell you honestly whether your anatomy supports an artificial disc, and what the alternative would offer instead. A GP or specialist referral is needed for a Medicare rebate.