Two-level Subsequent Surgical Interventions at the Index Level - Procedure Details

Group Associated AE(s) Subsequent Surgical Intervention Detail
Mobi-C (n=225) Hematoma Revision – repositioned inferior device during hematoma evacuation
Device migration Removed inferior device and converted to fusion
Ongoing bilateral arm pain Reoperation – cervical posterior foraminotomy of the inferior index level and the adjacent level below
Suboptimal bony fixation Removal of device at both levels and conversion to fusion
Neck and shoulder pain Removal of device at both levels and conversion to fusion
Facet spondylosis Reoperation – posterior bilateral facet decortication at both levels and posterior fusion hardware
Neck and arm pain  Removal of device at inferior level and conversion to fusion
Foraminal stenosis Revision - Foraminotomy at superior index level
Stenosis Removal of inferior device at inferior level and conversion to fusion; the superior level was left intact
 
Fusion (n=105) Pseudarthrosis at both levels Reoperation – posterior hemilaminotomy at both levels
Pseudarthrosis at both levels Supplemental fixation in the form of posterior instrumentation at both levels
Failure of fusion Removal of fusion hardware and repeat fusion at the index levels and addition of fusion at the superior adjacent level
Pseudarthrosis at the index level Removal of fusion hardware and repeat fusion at the inferior level
Spondylosis and arthrosis at superior level Removal of fusion hardware and repeat fusion at the superior level
Fusion failure Revision – posterior cervical facet fusion at inferior level
Pseudarthrosis at both levels Revision – posterior cervical fusion at both levels
Radiculopathy Reoperation – hemilaminotomy and posterior decompression at both levels
Pseudarthrosis at inferior level Supplemental fixation in the form of posterior fusion instrumentation at the inferior level
Pseudarthrosis at both levels Supplemental fixation in the form of posterior fusion instrumentation at both levels and the inferior adjacent level
Herniated disc at superior adjacent level Removal of fusion hardware and extension of fusion with fusion  to superior adjacent level
Degeneration at adjacent level Removal of fusion hardware and adjacent level anterior discectomy and arthroplasty
Facet syndrome and spondylosis Removal of fusion hardware and repeat fusion at inferior index level and extension of fusion at inferior adjacent level
Spinal stenosis  Revision - removal of fusion hardware and extension of fusion to inferior adjacent level
Herniated disc at inferior and superior
adjacent levels
 Removal of fusion hardware, disc replacement at superior adjacent level and fusion at inferior adjacent level
Motor vehicle accident Revision - posterior decompression at both index levels 
Cervical spondylosis at adjacent level Removal of fusion hardware and fusion at both adjacent levels 

One-level Subsequent Surgical Interventions at the Index Level - Procedure Details

Group Associated AE(s) Secondary Surgical Intervention Detail
Mobi-C (n=164) Right C4-C5 radiculopathies Reoperation - laparoscopic right C4-C5 cervical laminectomy
Radiculopathy and spondylosis Removal of device and conversion to fusion at index level
Recurrent neck pain Removal of device and conversion to fusion at the index level and one additional level
Device malpositioning Removal of device and conversion to fusion at the index level
Cervical discogenic pain Removal of device and conversion to fusion at the index level and at the adjacent level below
 
Fusion
(n=81)
Foraminal stenosis and pseudoarthrosis at the index level Supplemental fixation in the form of posterior instrumentation at index level
Failure of fusion Removal of fusion hardware and repeat fusion at the index level
Misplaced screw Removal of fusion hardware and addition of fusion at the adjacent level below
Pseudarthrosis at the index level and herniated disc at the adjacent level above Removal of fusion hardware and repeat fusion at the index level and addition of fusion at the adjacent level above and addition of fusion two levels above (three level fusion )
Pseudarthrosis at the index level and radiculopathy Supplemental fixation in the form of posterior fusion instrumentation at the index level
Pseudoarthrosis at the index level Supplemental fixation in the form of posterior fusion instrumentation at the index level
Herniated discs at adjacent levels Removal of fusion hardware and fusion at inferior adjacent levels  
Stenosis - cervical spine Removal of fusion hardware and addition of fusion at the adjacent level above
Radial postero-lateral fissuring at adjacent level Removal of fusion hardware  and total disc arthroplasty (ProDisc) at adjacent level