Reversal of Anterior Cervical Fusion by Placement of an Artificial Disc Prosthesis

Anterior cervical decompression and fusion is a very commonly performed procedure. Disc arthroplasty using artificial disc prostheses is a relatively new technology used to try and maintain normal motion at the levels instrumented. This is the first reported case of reversal of an instrumented cervical fusion using an artificial disc prosthesis.

History
This 38-year-old male initially presented 7 months previously with arm pain suggestive of a C6 radiculopathy. Imaging at that time showed a C6 disc protusion compressing the exiting C6 nerve roots with no cord compression. He underwent an anterior cervical decompression and fusion using allograft and a cervical locking plate (see image below):

Approximately 6 months after his initial surgery he was reviewed with new symptoms that had appeared after the initial surgery. He had pain and bilateral finger flexor and extensor weakness suggestive of bilateral C7 radiculopathies. Repeat imaging confirmed foraminal stenosis at the C6-7 level with no evidence of the cord compression (see below):

Lateral MRI

Axial (overhead) MRI

The C5-6 level had not completing fused but no movement occurred on flexion/extension studies and there was no evidence of hardware failure (see below):

Flexion

Extension

The patient requested surgical intervention for the C7 radiculopathies. It was felt that the arthrodesis at the C5-6 level had contributed to the failure of the C6-7 level. It was also requested, if at all possible to readdress the C5-6 level.

Preoperative high resolution CT scanning confirmed failure of fusion of the facet joints: