Three- and four-level anterior cervical discectomy and fusion with plate fixation: a prospective study

STUDY DESIGN: A prospective study of 15 patients who underwent modified Smith-Robinson anterior cervical discectomy and fusion at three or four operative levels stabilized with an unicortical anterior plate. OBJECTIVES: To provide medium-term follow-up data on the surgical success and patient outcome of three- and four-level anterior cervical discectomies and fusions and to determine the effect that plate fixation has on the results. SUMMARY OF BACKGROUND DATA: The success of arthrodesis for anterior cervical fusion depends on several factors, including the number of surgical levels. The arthrodesis rate and outcome for patients having three- and four-level discectomy and fusion procedures is disappointing. Internal fixation putatively improves these parameters. METHODS: Fifteen patients (average age, 51 years; range, 35-77), were observed for an average of 42 months (range, 25-73) All had an anterior discectomy, burring of the endplates, placement of an autogenous tricortical iliac crest graft at three (12 patients) or four (3 patients) levels, and application of a Cervical Spine Locking Plate. All patients had follow-up office visits with examinations and radiographs. Radiographic union, postoperative pain relief, and neurologic recovery were evaluated. RESULTS: Solid arthrodesis was achieved at all levels in only 7 (47%) of the 15 patients after a single procedure. Of the 8 patients with pseudarthrosis, 3 had sufficient pain to necessitate revision surgery (with pain relief in two), 1 had pain without further surgery, and 4 no pain. Of the 7 with solid fusion, 3 had persistent pain, and 4 had none. Two in this group had a second procedure. All 4 patients with preoperative myelopathy improved, and 10 of the 11 with radiculopathy had resolution of arm symptoms. CONCLUSIONS: Three- and four-level modified Robinson cervical discectomy and fusion results in an unacceptably high rate of pseudarthrosis. The Cervical Spine Locking Plate alone does not appear to improve the arthrodesis rate.