Study design: A prospective study.
Objective: To evaluate the 2-year outcomes of open-door cervical laminoplasty with prophylactic bilateral C4-C5 foraminotomy.
Summary of background data: A prospective trial of prophylactic bilateral C4-C5 foraminotomy with open-door laminoplasty for cervical compression myelopathy showed a significant efficacy for preventing postoperative C5 palsy. However, in bilateral foraminotomy, there are concerns such as postoperative instability, hinge fracture, or nonunion, which may cause deterioration of neurological symptoms and neck pain.
Methods: A prospective trial was performed in 141 patients between 2009 and 2010 (group F). A group of 141 patients who underwent open-door laminoplasty without prophylactic foraminotomy from 2006 to 2008 served as a control group (group NF). Here, we report 2-year radiological and clinical data for 121 patients (follow-up rate: 85.8%) in group F and 115 patients (81.6%) in group NF. The 2 groups were demographically similar, except for the operation time.
Results: In group F, the mean rate of facet joint preservation was 71.4%. C2-C7 and C4-C5 lordosis and C4 translational movement were maintained postoperatively in both groups. The range of motion of C2-C7 and C4-C5 significantly decreased to about 80% of the preoperative values in both groups (P < 0.01). These radiological parameters and the incidence of hinge fracture and nonunion did not differ significantly between the groups. Visual analogue scale scores for neck pain were unchanged and significant recoveries (P < 0.001) in Japanese Orthopaedic Association scores were found in both groups. There were no significant differences in these clinical scores between the groups. The incidences of C5 palsy were 1.7% and 7.0% in groups F and NF, respectively (P = 0.043).
Conclusion: Prophylactic bilateral C4-C5 foraminotomy did not adversely affect the 2-year radiological and clinical outcomes. Therefore, we conclude that this approach is an effective and desirable procedure for preventing postoperative C5 palsy.
Level of evidence: 3.