Study design: Case report and review of the literature.
Objective: To present a conversion of an anterior cervical discectomy and fusion (ACDF) with a cervical artificial disc replacement in a 39-year-old woman and to review the relevant literature.
Summary of background data: Return of functional spinal unit motion 9 years after attempted fusion is extremely rare.
Methods: The patient underwent an attempted anterior cervical discectomy and fusion 9 years earlier for bilateral hand numbness and leg weakness. Most of her neurological deficits had resolved after the index operation, but returned 2 months before the second operation and were unresponsive to nonoperative treatment. Computed tomography (CT) myelography showed recurrence of cervical disc herniation at the cephalad adjacent segment, which compressed the spinal cord. There was still some osteophyte at the C5/6 level that was also causing compression to the spinal cord. A solid fusion was suspected at this level. Surgery was performed to take down the grafted region and replace both levels with artificial disks.
Results: The range of motion (ROM) of the revised level at the 6-month follow-up was well preserved, there was no sign of instability at either operated level. The 6-month follow-up CT scan shows that, there was no obvious compression in the spinal canal. The remobilized facet joints of C5/6 segment have not demonstrated further degeneration. The patient's neck symptom and neurological function were significantly recovered.
Conclusions: This case demonstrates application of a cervical artificial disc replacement to restore motion at a level that was previously grafted and fused. In select cases, cervical artificial disc replacement may represent a reasonable alternative to a repeated attempt at fusion. It is imperative that preoperatively lack of fusion of the facet joints be demonstrated on reconstructed CT scanning.