[Auric]

#10841

Well, the Avs are still in the playoffs and the Red Wings are not. Congrats.

This is the story of a failed PEEK cage ACDF for C6/C7 and pseudoarthrosis. The cage failed for a curious reason. Read on.

In September of 2011, I fielded three diagnoses for neck pain, finger tingling and right triceps atrophy. A prominent orthopedic surgeon recommended fusions from C4 to C7, a second OS said C5 to C7, and the last doctor, a neurosurgeon, said only C6/C7.

All were to use PEEK cages, the first two with instrumentation, the last without.

I went with the neurosurgeon, a man of thirty-three years experience in a high-visibility hospital. C6/C7, no plating, PEEK cage, four weeks in a collar.

The chosen MD had some uncommon post-op opinions. Chief among them was the belief that fusion is not a vital outcome to an ACDF. Instead, restoring the foramen height (space between the vertebrae) trumps all other concerns. To this end, he did not call for post-op X-rays.

Nevertheless, after the operation, there was improvement in the acute symptoms on the right.

But a new neck pain emerged in the left trapezius (or beneath in the levator scapula). In mid-2013, I began a new series of diagnostics: an MRI, a CT myelogram, and a CT bone scan.

Regarding the disks, nothing had much improved. Notably, I had disc protrusion at C6/C7, a interesting fact as a “discectomy” would in theory remove the disk, so what was left to protrude? And there was a remaining posterior osteophtye at that same juncture, not addressed in the surgery.

Dr. Corenman read the MRI and said that C4/5 was “a five,” C5/6 was an “eight” (it had ‘given up the ghost’), and C6/7 was an “eight.” (Ten on this scale is the worst.)

He opined that there was no fusion.

Dr. Corenman did not see the other two tests. But neither report brought much clarity. One was phrased in a double-negative, medical speak like,” We cannot rule out that fusion has not occurred.”

So I went to the Maestro in town who has a reputation for revision surgery, the doctor who takes the cases no one else wants. He, like Dr. Corenman, is dubious of PEEK cages. (They subtract from the surface contact area of bone on bone which may slow or negate fusion.)

In March of 2014 (coming on seven weeks ago), I had a second operation: allograft, instrumentation, C6/7 revision and C5/6. Finally we’d step beyond the inconclusive tests and see what was really going on in there.

Not only was there “gross motion” in C6/C7 (no fusion), the second surgeon found residual disk material underlying the PEEK cage, interposed between the top of C7 and the cage itself. From the moment I was sewn up in that first operation, I had no chance of fusion.

After the operation, six weeks were spent in a hard collar. Physical therapy is currently underway.

A couple of questions for Dr. Corenman.

1. What do you make of this belief, that fusion is less important than restoring foramen height using a PEEK cage? Simplistically speaking, if you’ve got a device propping up the span between the bones, and the nerves exit without impingement, you’d get better, right?

But if it doesn’t fuse, the PEEK cage is not fixed. Even if it’s counter-sunk into the bone, it’s still moving. I imagine this aggravates the surrounding tissue, with inflammation, grinding, and weight on adjoining disks.

Only once did I hear that neurosurgeon’s opinion echoed: in a press release from a maker of PEEK cages. Indeed, PEEK cages seem to be invented for a problem that did not exist. If a patient did not want the added incision of an iliac crest transplant to use his own bone, then cadaver bone, statistically speaking, has a pretty good track record too.

By the way, that high-visibility hospital abruptly stopped using PEEK cages for cervical surgeries soon after my 2011 operation.

2. When you do PEEK cage revisions, how commonly have you found residual disk material underlying a PEEK cage?

Though I lament the need to continue visiting your site, your site continues to rock…

[Donald Corenman, MD, DC]

#10846

You know what my opinion is of PEEK cages in the cervical spine. They are not as effective as biologically active grafts.

Fusion is vital to a successful result. It might be true that a small percentage of patients without fusion are asymptomatic but the majority of patients with a pseudoarthrosis have symptoms. In addition, the residual motion can regrow osteophytes (bone spurs) and redevelop arm pain from foraminal stenosis (see website).

Using a PEEK cage and not using a plate is an invitation to a non-union.

The PEEK cage generally is inserted after complete removal of disc (nucleus) material and the cartilage endplate. If these are not removed, there is no biological surface that can bond with bone to the opposite side.

Dr. Corenman

PLEASE REMEMBER, THIS FORUM IS MEANT TO PROVIDE GENERAL INFORMATION ON SPINE ANATOMY, CONDITIONS AND TREATMENTS. TO GET AN ACCURATE DIAGNOSIS, YOU MUST VISIT A QUALIFIED PROFESSIONAL IN PERSON.
 
Donald Corenman, MD, DC is a highly-regarded spine surgeon, considered an expert in the area of neck and back pain. Trained as both a Medical Doctor and Doctor of Chiropractic, Dr. Corenman earned academic appointments as Clinical Assistant Professor and Assistant Professor of Orthopaedic Surgery at the University of Colorado Health Sciences Center, and his research on spine surgery and rehabilitation has resulted in the publication of multiple peer-reviewed articles and two books.

[Auric]

#10854

A point of emphasis in my question was, as a Doctor who revises such a procedure, how often do you find extraneous disk residue laying between the very points of contact that were intended to fuse?

By the way, do you still have a video planned about revising PEEK cages? We talked about it last November, and I’m still looking forward to it. Hey, if you need any diagnostic test examples, give me a call and I’ll send the films.

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